BREEDING & GENETICS OF FRUIT CROPS FOR COLD CLIMATES

• Sponsoring Institution: State Agricultural Experiment Station
• Project Status: COMPLETE
• Funding Source: STATE
• Reporting Frequency: Annual
• Accession No.: 0001840
• Project Start Date: Jul 1, 2010
• Project End Date: Jun 30, 2015
• Program Code: [(N/A)]- (N/A)

Recipient Organization
UNIV OF MINNESOTA
(N/A)
ST PAUL,MN 55108

Performing Department
Horticultural Science

Non Technical Summary
Fruits are a critical component of a healthy and pleasurable diet, being sources of dietary fiber, vitamins, minerals, antioxidants, and other phytonutrients. Temperate fruit crops in the U.S. have a farm value exceeding $10 billion while Minnesota fruit crops probably have an annual farm value of about $20 to 30 million. In Minnesota, fruit crops are mainly produced on small farms and often direct-marketed to consumers as part of a diversified cropping scheme with other specialty crops. Their production is frequently associated with tourism and other added-value enterprises. For example, the farm value of the grape crop in Minnesota in 2007 was less than $5 million, but the estimated economic impact for grapes and wine was $36 million. Additional value of fruit crops is derived from sales of nursery stock and from consumer-grown produce. Minnesota fruit growing is dependent on germplasm developed at the University of Minnesota. Over two thirds of the apple and grape production, all blueberry production, and a significant proportion of strawberry and raspberry production are based on cultivars developed at the University or their direct descendants. Despite advances in apple and grape genomics, marker-assisted breeding (MAB) implementation has been minimal in U.S. fruit breeding programs. These crops have long generation times before the commercial product (fruit) can be evaluated. Evaluation of individual plants requires intensive greenhouse and/or extensive field space and thus, is expensive. Using genetic markers to indirectly select for desirable traits is an obvious opportunity, but has not been implemented due to significant technical, economic, logistical, and informational barriers. In this project, we will develop new varieties of fruit crops using conventional hybridization and selection. We will make selection more efficient by finding DNA markers linked to genes that control traits of interest. By selecting the proper marker, we will be able to select for a fruit trait before the plant fruits or a disease resistance trait even in the absence of the disease. New varieties of apples, grapes, and other fruits developed under this project are benefiting fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers are benefiting from their superior eating qualities and health-related traits. Knowledge developed in the genetics of fruit crops including development of DNA markers for use in marker-aided breeding should improve the efficiency of fruit breeding programs and increase the probability of obtaining new fruit varieties with desired features.

Animal Health Component

(N/A)

Research Effort Categories

Basic

(N/A)

Applied

(N/A)

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
201	1110	1080	20%
201	1131	1080	20%
201	1199	1080	10%
203	1131	1080	10%
204	1110	1080	10%
204	1131	1080	10%
212	1110	1080	10%
212	1199	1080	10%

Knowledge Area
212 - Pathogens and Nematodes Affecting Plants; 204 - Plant Product Quality and Utility (Preharvest); 203 - Plant Biological Efficiency and Abiotic Stresses Affecting Plants; 201 - Plant Genome, Genetics, and Genetic Mechanisms;

Subject Of Investigation
1110 - Apple; 1131 - Wine grapes; 1199 - Deciduous and small fruits, general/other;

Field Of Science
1080 - Genetics;

Keywords

fruit breeding

apple breeding

grape breeding

dna marker

marker assisted breeding

pedigree based analysis

anthocyanin

tannin

Goals / Objectives
Objectives 1.Develop, evaluate, and release fruit cultivars with horticultural, disease and pest resistance, and fruit quality characters desired by growers and consumers in Minnesota and similar cold climate production areas.Our primary crops are apple and grape with more minor efforts other crops such as blueberry, blackberry, and strawberry. Outputs will include new cultivars and germplasm. 2.Develop tools and knowledge base of phenotype and genotype information for critical traits to enable DNA marker assisted breeding for critical traits in apple and grape. We will focus on 2a) traits related to fruit quality and apple scab resistance in apple and 2b) traits related to fruit quality and climate adaptation in grape. Outputs will include phenotype and genotype information needed to perform DNA marker assisted breeding. 3.Contribute to the education of students through their involvement in the prior objectives.

Project Methods
Objective 1.Increasing emphasis is being placed on consumer product appeal, and disease resistance along with improvement of cold hardiness and other horticultural traits. Juvenile phase, or early stage, selection protocols include minimal use or elimination of pesticides in order to evaluate disease and pest resistance. Meritorious selections are evaluated further at these sites as well as in plantings of cooperating growers and at other experiment stations. Outstanding selections are made available to appropriate propagators and producers. In conjunction with the advanced testing of Minnesota selections, cultivars and selections released by other breeding programs will be evaluated and information on their adaptation and performance will be disseminated to the public through programs of the University of Minnesota Extension Service. Objective 2. In apple, Single nucleotide polymorphism (SNP) markers will be developed in collaboration with Bassil (USDA-ARS) and Main (Washington State University) at a resolution of at least one polymorphic SNP marker every 5 cM in any random cross, for use in Pedigree-Based Analysis (PBA) using FlexQTL software. We will utilize PBA to establish and exploit marker-trait associations by 1) using founder germplasm sets to discover SNP markers and 2) phenotyping germplasm sets for important fruit quality traits using standardized phenotyping protocols. Germplasm sets will be genotyped genome-wide with SNP markers and phenotyped for fruit quality traits and other high-impact traits. Phenotyping protocols and PBA results for germplasm sets will be archived and made publicly available for reference at www.rosbreed.org. We also will determine the inheritance of, and useful markers for, resistance to apple scab (Venturia inaequalis) in Honeycrisp, an apple cultivar developed by, and used extensively in, our breeding program. In grape, we have identified regions on linkage groups 11 and 13 associated with dormancy induction in the greenhouse and field, respectively, and winter injury (LG 11) in a F2 V. riparia x Seyval mapping population we will also attempt to identify QTL for chilling requirement needed to break dormancy, and anthocyanin, phenolic and acid levels in this population QTL analysis will be conducted by scoring each individual of the F2 population and mapping phenotypic information onto the genetic linkage map. Using information from the VitisNet integration of -omics information, we will attempt to identify candidate genes related to these traits in genomic regions indicated by QTL analysis. Testing for segregation of functional alleles will be conducted in the F2 population using SNP markers developed based on candidate gene sequences. We will phenotype representative accessions from our germplasm including cultivars, breeding selections, important ancestors and founders, for variation in levels of individual organic acids (e.g. tartaric, malic, citric),flavonoids (e.g. anthocyanins and tannins), and related metabolites.

Progress 07/01/10 to 06/30/15

Outputs
Target Audience:The target audience for new varieties of fruit crops is US producers and ultimately fruit consumers. Numerous fruit varieties from this project were produced by fruit producers during this reporting period. This includes apples (Honeycrisp, Minnewashta (Zestar! brand), Minneiska (SweeTango brand), Wildung (SnowSweet brand), and Frostbite), grapes (Frontenac, Frontenac gris, Marquette, and La Crescent), blueberries (Northblue, St. Cloud, Polaris, Chippewa, Superior, and others), and strawberries (Mesabi, Itasca and Winona). The Honeycrisp apple has had a large impact on the production and profitability of the US apple industry as it is produced in every apple producing region. The 2014 Honeycrisp crop was estimated as at least 8 million bushels with a farmgate value of at least $350 million. These 8 million bushels provided over 500 million apple fruits for the nutrition and delight of US consumers. The target audience for new knowledge in genetics, breeding and selection of fruit crops is primarily other public and private sector scientists involved in similar activities. These audiences were reached via publications and presentations at scientific meetings. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?One MS student was trained under the project during the reporting period (David Munter). Three PhD students were trained under the project during the reporting period (Nicholas Howard, Soon Li Teh, and Elizabeth Blissett ). One postdoctoral student (Matthew Clark) was trained completed his degree. Graduate student Teh presented research at the Plant and Animal Genome Conference, San Diego, Jan 2015. How have the results been disseminated to communities of interest?Cultivars have been made available to fruit producers through commercial nurseries. Knowledge developed toward DNA marker assisted selection has been made available in scientific publications and presentations at scientific meetings. Graduate students trained in the project have taken professional positions. What do you plan to do during the next reporting period to accomplish the goals?This project is terminated.

Impacts
What was accomplished under these goals? Objective 1. In 2015 the apple breeding program completed 63 crosses producing 11,464 seeds. Marker assisted selection was used to screen 804 seedlings and discard 295 from populations produced by crosses in 2014. A total of 3039 seedlings were grafted for first level evaluation in the test orchard. There are 119 selections in the second test phase, including 15 new selections that were identified in 2015. There were 162 trees marked for further evaluation of promising characteristics and 2221 trees that were discarded from seedling blocks based on field evaluations. Seven selections are presently in advanced testing at multiple sites across the US. One promising selection was chosen for public release and propagation material was distributed to a commercial nursery to begin tree build up for public sales in approximately 2018. There are presently 9 selections of hybrid pears from previous crosses under evaluation. In 2015, 7 selections were sent to 14 commercial test sites in Minnesota for further evaluation. Studies were conducted to determine self and cross fertility of these selections. There are 7 selections of sweet cherries under evaluation. In 2015, 3 selections were sent to 9 commercial test sites in Minnesota for further evaluation. Objective 2. In grape, approximately 600 individuals from four populations were genotyped for SNP and SSR DNA markers. Phenotype data were collected in the vineyard for powdery mildew, downy mildew, black rot, 2,4-D damage, foliar phylloxera, flower sex, and fruit color to facilitate mapping of markers for these traits as part of the Vitisgen project sponsored in part by the USDASpecialty Crops Research Initiative. A glasshouse phylloxera resistance study was conducted on one VitisGen mapping population. Mapping of markers and quantitative trait loci has indicated two major loci controlling powdery mildew resistance which should allow for DNA tests that can be used in selection of parents and seedlings. Leaf samples from 2014 crosses were collected and submitted for genotyping with SSR markers to enable marker assisted selection for powdery mildew resistance. Leaf samples were collected and submitted for genotype by sequencing from a diversity set that includes key selections and ancestors in UMN program to enable parent selection and QTL discovery and functional haplotype assessment. In apple, approximately 100 individuals were screened for apple scab resistance to develop DNA tests to predict apple scab resistance acquired from the cultivar Wildung. In the breeding program DNA tests for apple skin color amount, fruit firmness, crispness, juiciness, acidity, and storability and apple scab resistance were used to help select the best parents to combine and the best seedlings to advance. Over 400 apple individuals were assessed for soft scald, bitter pit, internal browning and other fruit storage disorders as well as Honeycrisp-derived leaf chlorosis to attempt to develop DNA markers to predict which individuals are prone to these disorders. The use of a silica bead DNA extraction protocol for use in high throughput PCR based genotyping such as SSRs, indel, and KASP markers was investigated. Objective 3. Three PhD and one MS students and one postdoctoral student were trained and educated during this period as part of the project.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Peace C, Bassil N, Coe M, Finn C, Gasic K, Hokanson S, Luby J, Main D, McFerson J, Norelli J, Olmstead M, Whitaker V, Yue C, Iezzoni A. 2015. RosBREED: A pedigree of amazing germplasm, traditional genetics, international collaboration, and DNA-based technologies. CROPS 2015: Genomics Enabled Crop Breeding & Improvement, Huntsville, AL.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Iezzoni A, Peace C, Bassil N, Coe M, Finn C, Gasic K, Luby J, Main D, McFerson J, Norelli J, Olmstead M, Whitaker V, Yue C. 2015. RosBREED2: Progress and future plans to enable DNA-informed breeding in the Rosaceae. XI International Rubus and Ribes Symposium, Asheville, NC.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Iezzoni A, Peace C, Bassil N, Coe, M, Finn C, Gasic K, Hokanson S, Luby J, Main D, McFerson J, Norelli J, Olmstead M, Whitaker V, Yue C. 2015. RosBREED2: More traits, additional crops, expanded germplasm, new science. Presentation at the American Society for Horticultural Science conference in New Orleans, LA, August, 2015.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Iezzoni A, Peace C, Bassil N, Coe M, Finn C, Gasic K, Luby J, Main D, McFerson J, Norelli J, Olmstead M, Whitaker V, Yue C. 2015. RosBREED2: Progress and future plans to enable DNA-informed breeding in the Rosaceae. XIV Eucarpia Fruit Breeding and Genetics Symposium June 14-18. Bologna.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Yue, C., R.K. Gallardo, J. Luby, A. Rihn, J. McFerson, V. McCracken, T. Gradziel, K. Gasic, G. Reighard, J. Clark, C. Weebadde, A. Sebolt, A. Iezzoni. 2014. An evaluation of United States peach fruit producers trait prioritizationevidence from audience clicker surveys. HortScience. 49:1309-1314.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Castro, P., J.M. Bushakra, P. Stewart, C.K. Weebadde, D. Wang, J.F. Hancock, C.E. Finn, J.J. Luby, K.S. Lewers. 2015. Genetic mapping of day-neutrality in cultivated strawberry. Molecular Breeding. 35: DOI 10.1007/s11032-015-0250-4.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Luby, J.J. and D.S. Bedford. 2015. Cultivars as consumer brands: trends in protecting and commercializing apple cultivars via intellectual property rights. Crop Sci. 55:2504-2510. doi: 10.2135/cropsci2014.10.0684.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Gallardo, R.K., Hanrahan, I., Hong, Y., and J. Luby. 2015 Crop load management and the market profitability of Honeycrisp. HortTechnology 25:575-584.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Sooriyapathirana, S., S. Mookerjee, C.K. Weebadde, C.E. Finn, K. Lewers, J.M. Bushakra, J. Luby, P. Stewart, J.F. Hancock. 2015. Identification of QTL associated with flower and runner production in octoploid strawberry (Fragaria �ananassa). J. Berry Research. DOI: 10.3233/JBR-150095.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Gallardo, R.K., H. Li, V. McCracken, C. Yue, J. Luby, J. McFerson. 2015. Market intermediaries ratings of importance for Rosaceous fruit quality attributes. International Food and Agribusiness Management Review 18:121-154.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Edge-Garza, D.A., J.J. Luby, C. Peace. Decision support for cost-efficient and logistically feasible marker-assisted seedling selection in fruit breeding. 2015 Molec. Breeding 35: DOI 10.1007/s11032-015-0409-z.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: " Teh SL, Clark MD, Hemstad P, Fresnedo Ramirez J, Sun Q, Cadle-Davidson L, Hegeman A, Luby J. (2015) QTL Identification in an Interspecific Grapevine Cross Segregating for Resistance to Powdery Mildew, Downy Mildew, Black Rot, and Phylloxera. International Plant & Animal Genome XXII. San Diego, CA #P0887.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Luby, J.J. Cold climate wineand table grapes. American Soc. for Horticultural Science Annual Conference. Aug. 5, 2015. New Orleans. Recorded presentation available at https://ashs.confex.com/ashs/2015/webprogram/Paper22445.html.

Progress 10/01/14 to 06/30/15

Outputs
Target Audience:The target audience for new varieties of fruit crops is US producers and ultimately fruit consumers. Numerous fruit varieties from this project were produced by fruit producers during this reporting period. This includes apples (Honeycrisp, Minnewashta (Zestar! brand), Minneiska (SweeTango brand), Wildung (SnowSweet brand), and Frostbite), grapes (Frontenac, Frontenac gris, Marquette, and La Crescent), blueberries (Northblue, St. Cloud, Polaris, Chippewa, Superior, and others), and strawberries (Mesabi, Itasca and Winona). The Honeycrisp apple has had a large impact on the production and profitability of the US apple industry as it is produced in every apple producing region. The 2014 Honeycrisp crop was estimated as at least 8 million bushels with a farmgate value of at least $350 million. These 8 million bushels provided over 500 million apple fruits for the nutrition and delight of US consumers. The target audience for new knowledge in genetics, breeding and selection of fruit crops is primarily other public and private sector scientists involved in similar activities. These audiences were reached via publications and presentations at scientific meetings. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?One MS student was trained under the project during the reporting period (David Munter). Three PhD students were trained under the project during the reporting period (Nicholas Howard, Soon Li Teh, and Elizabeth Blissett ). One postdoctoral student (Matthew Clark) was trained completed his degree. Graduate student Teh presented research at the Plant and Animal Genome Conference, San Diego, Jan 2015. How have the results been disseminated to communities of interest?Cultivars have been made available to fruit producers through commercial nurseries. Knowledge developed toward DNA marker assisted selection has been made available in scientific publications and presentations at scientific meetings. Graduate students trained in the project have taken professional positions. What do you plan to do during the next reporting period to accomplish the goals?This project is terminated.

Impacts
What was accomplished under these goals? Objective 1. In 2015 the apple breeding program completed 63 crosses producing 11,464 seeds. Marker assisted selection was used to screen 804 seedlings and discard 295 from populations produced bycrossesin 2014. A total of 3039 seedlings were grafted for first level evaluationin the test orchard. There are 119 selections in the second test phase, including 15 new selections that were identified in 2015. There were162 trees marked for further evaluation of promising characteristicsand 2221 trees that were discarded from seedling blocks based on field evaluations. Seven selections are presently in advanced testing at multiple sites across the US. One promising selection was chosen for public release and propagation material was distributed to a commercial nursery to begin tree build up for public sales in approximately 2018. There are presently 9 selections of hybrid pears from previous crosses under evaluation. In 2015, 7 selections were sent to 14 commercial test sites in Minnesota for further evaluation. Studies were conducted to determine self and cross fertility of these selections. There are 7 selections of sweet cherries under evaluation. In 2015, 3 selections were sentto 9 commercial test sites in Minnesota for further evaluation. Objective 2. In grape, approximately 600 individuals from four populations were genotyped for SNP and SSR DNA markers. Phenotype data were collected in the vineyard for powdery mildew, downy mildew, black rot, 2,4-D damage, foliar phylloxera, flower sex, and fruit color to facilitate mapping of markers for these traits as part of the Vitisgen project sponsored in part by the USDA-Specialty Crops Research Initiative. A glasshouse phylloxera resistance study was conducted on one VitisGen mapping population. Mapping of markers and quantitative trait loci has indicated two major loci controlling powdery mildew resistance which should allow for DNA tests that can be used in selection of parents and seedlings. Leaf samples from 2014 crosses were collected and submitted for genotyping with SSR markers to enable marker assisted selection for powdery mildew resistance. Leaf sampleswere collected and submitted for genotype by sequencing from a diversity set that includes key selections and ancestors in UMN program to enable parent selection and QTL discovery and functional haplotype assessment. In apple, approximately 100 individuals were screened for apple scab resistance to develop DNA tests to predict apple scab resistance acquired from the cultivar Wildung. In the breeding program DNA tests for apple skin color amount, fruit firmness, crispness, juiciness, acidity, and storability and apple scab resistance were used to help select the best parents to combine and the best seedlings to advance. Over 400 apple individuals were assessed for soft scald, bitter pit, internal browning and other fruit storage disorders as well as Honeycrisp-derived leaf chlorosis to attempt to develop DNA markers to predict which individuals are prone to these disorders. The use of a silica bead DNA extraction protocol for use in high throughput PCR based genotyping such as SSRs, indel, and KASP markers was investigated. Objective 3. Three PhD and one MS students and one postdoctoral student were trained and educated during this period as part of the project.

Publications

• Type: Journal Articles Status: Published Year Published: 2014 Citation: Yue, C., R.K. Gallardo, J. Luby, A. Rihn, J. McFerson, V. McCracken, T. Gradziel, K. Gasic, G. Reighard, J. Clark, C. Weebadde, A. Sebolt, A. Iezzoni. 2014. An evaluation of United States peach fruit producers trait prioritizationevidence from audience clicker surveys. HortScience. 49:1309-1314.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Castro, P., J.M. Bushakra, P. Stewart, C.K. Weebadde, D. Wang, J.F. Hancock, C.E. Finn, J.J. Luby, K.S. Lewers. 2015. Genetic mapping of day-neutrality in cultivated strawberry. Molecular Breeding. 35: DOI 10.1007/s11032-015-0250-4.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Luby, J.J. and D.S. Bedford. 2015. Cultivars as consumer brands: trends in protecting and commercializing apple cultivars via intellectual property rights. Crop Sci. 55:2504-2510. doi: 10.2135/cropsci2014.10.0684.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Gallardo, R.K., H. Li, V. McCracken, C. Yue, J. Luby, J. McFerson. 2015. Market intermediaries ratings of importance for Rosaceous fruit quality attributes. International Food and Agribusiness Management Review 18:121-154.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Edge-Garza, D.A., J.J. Luby, C. Peace. Decision support for cost-efficient and logistically feasible marker-assisted seedling selection in fruit breeding. 2015 Molec. Breeding 35: DOI 10.1007/s11032-015-0409-z.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: " Teh SL, Clark MD, Hemstad P, Fresnedo Ramirez J, Sun Q, Cadle-Davidson L, Hegeman A, Luby J. (2015) QTL Identification in an Interspecific Grapevine Cross Segregating for Resistance to Powdery Mildew, Downy Mildew, Black Rot, and Phylloxera. International Plant & Animal Genome XXII. San Diego, CA #P0887.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Luby, J.J. Cold climate wineand table grapes. American Soc. for Horticultural Science Annual Conference. Aug. 5, 2015. New Orleans. Recorded presentation available at https://ashs.confex.com/ashs/2015/webprogram/Paper22445.html.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Peace C, Bassil N, Coe M, Finn C, Gasic K, Hokanson S, Luby J, Main D, McFerson J, Norelli J, Olmstead M, Whitaker V, Yue C, Iezzoni A. 2015. RosBREED: A pedigree of amazing germplasm, traditional genetics, international collaboration, and DNA-based technologies. CROPS 2015: Genomics Enabled Crop Breeding & Improvement, Huntsville, AL.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Iezzoni A, Peace C, Bassil N, Coe M, Finn C, Gasic K, Luby J, Main D, McFerson J, Norelli J, Olmstead M, Whitaker V, Yue C. 2015. RosBREED2: Progress and future plans to enable DNA-informed breeding in the Rosaceae. XI International Rubus and Ribes Symposium, Asheville, NC.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Gallardo, R.K., Hanrahan, I., Hong, Y., and J. Luby. 2015 Crop load management and the market profitability of Honeycrisp. HortTechnology 25:575-584.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Sooriyapathirana, S., S. Mookerjee, C.K. Weebadde, C.E. Finn, K. Lewers, J.M. Bushakra, J. Luby, P. Stewart, J.F. Hancock. 2015. Identification of QTL associated with flower and runner production in octoploid strawberry (Fragaria �ananassa). J. Berry Research. DOI: 10.3233/JBR-150095.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Iezzoni A, Peace C, Bassil N, Coe, M, Finn C, Gasic K, Hokanson S, Luby J, Main D, McFerson J, Norelli J, Olmstead M, Whitaker V, Yue C. 2015. RosBREED2: More traits, additional crops, expanded germplasm, new science. Presentation at the American Society for Horticultural Science conference in New Orleans, LA, August, 2015.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Iezzoni A, Peace C, Bassil N, Coe M, Finn C, Gasic K, Luby J, Main D, McFerson J, Norelli J, Olmstead M, Whitaker V, Yue C. 2015. RosBREED2: Progress and future plans to enable DNA-informed breeding in the Rosaceae. XIV Eucarpia Fruit Breeding and Genetics Symposium June 14-18. Bologna.

Progress 10/01/13 to 09/30/14

Outputs
Target Audience: The target audience for new varieties of fruit crops is US producers and ultimately fruit consumers. Numerous fruit varieties from this project were produced by fruit producers during this reporting period. This includes apples (Honeycrisp, Minnewashta (Zestar! brand), Minneiska (SweeTango brand), Wildung (SnowSweet brand), and Frostbite), grapes (Frontenac, Frontenac gris, Marquette, and La Crescent), blueberries (Northblue, St. Cloud, Polaris, Chippewa, Superior, and others), and strawberries (Mesabi, Itasca and Winona). The Honeycrisp apple has had a large impact on the production and profitability of the US apple industry as it is produced in every apple producing region. The 2013 Honeycrisp crop was estimated as at least7 million bushels with a farmgate value of at least $350 million. These 7million bushels provided over 400 million apple fruits for the nutrition and delight of US consumers. The target audience for new knowledge in genetics, breeding and selection of fruit crops is primarily other public and private sector scientists involved in similar activities. These audiences were reached via publications and presentations at scientific meetings. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? OneMS student was trained under the project during the reporting period (David Munter). Three PhD students were trained under the project during the reporting period (Nicholas Howard, Soon Li Teh, and Matthew Clark). One PhD student (Clark) completed his degree. Graduate student Clarkpresented research at the Plant and Animal Genome Conference,San Diego, Jan 2014. Soon Li Teh attended spent twoweeks on a travel-training fellowship atUSDA-ARS/Cornell Univ in Geneva NY in the laboratory of Lance Cadle-Davidson to learn techniques in plant pathology and computational biology in July 2014. How have the results been disseminated to communities of interest? Cultivars have been made available to fruit producers through commercial nurseries. Knowledge developed toward DNA marker assisted selection has been made available in scientific publications and presentations at scientific meetings. Graduate students trained in the project have taken professional positions. What do you plan to do during the next reporting period to accomplish the goals? Obj. 1 Crossing will continue in apples and grapes. Evaluation of selections will continue in apples, grapes, and berry crops. Obj 2 Inheritance of apple scab infections and post harvest fruit disorders in progeny of Honeycrisp apple will be determined so that resistance loci linked to DNA markers can be used for selection. Resistance to grape diseases will be determined so that resistance loci linked to DNA markers can be used for selection Obj 3 Two PhD students and 1 MS student will continue their training and education.

Impacts
What was accomplished under these goals? Objective 1. In the apple breeding program 56 crosses were made in 2014 producing 10,281 seeds. Marker assisted selection was used to discard 1446 seedlings from 2013 crossesand the remaining 4960 seedlings were grafted in the orchard for first evaluation. There are 116 selections insecond test phase including 16 new selections that were made in 2014. There were 137 trees marked for further evaluation of promising characteristics and 2116 trees that were discarded from seedling blocks based on field evaluations. Six selections are in advanced testing at multiple sites across the US and a seventh selection will be distributed in Spring 2015 In the grape breeding program,?24 crosses were made in 2014 producing?2072?seeds. From 2013 crosses, ?5455 seeds were produced and?3279 seedlings were planted in the disease screening nursery for initial evaluation. Following screening in the 2013 nursery, ?627? seedlings from 2012 crosses were planted in the vineyard in 201?4. Approximately75 selections are in second test phase and ?9?new selections were made in 2014.?One white wine selection is currently being distributed to commercial nurseries in anticipation of being named and released to the public. ?In addition, ?14? rootstock selections are in second test. Objective 2. In grape, approximately 600 individuals from four populations were genotyped for SNP and SSR DNA markers. Phenotype data were collected for powdery mildew, downy mildew, black rot, 2,4-D damage, foliar phylloxera, flower sex, and fruit color to facilitate mapping of markers for these traits as part of the Vitisgen project sponsored in part by the USDA-Specialty Crops Research Initiative. Mapping of markers and quantitative trait loci for these traits is being conducted to develop predictive DNA tests that can be used in selection of parents and seedlings. In apple, DNA tests were developed to predict apple scab resistance acquired from the cultivar Honeycrisp. In the breeding program DNA tests for apple skin color amount, fruit firmness, crispness, juiciness, acidity, and storability and apple scab resistance were used to help select the best parents to combine and the best seedlings to advance. Objective 3. Three PhD andone MS students were trained and educated during this period as part of the project. One PhD studentsss completed a thesis and degree.

Publications

• Type: Journal Articles Status: Published Year Published: 2014 Citation: Peace, C.P., J.J. Luby, W.E. van de Weg, M.C.A.M Bink, A.F.Iezzoni. 2014. A strategy for developing representative germplasm sets for systematic QTL validation, demonstrated for apple, peach, and sweet cherry. Tree Genetics & Genomes. 10:1679-1694.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Gallardo, R.K., H. Li, V. McCracken, C. Yue, J. Luby, and J. McFerson. 2014. Market intermediaries willingness to pay for apple, peach, cherry, and strawberry quality attributes. Agribusiness: An International Journal. DOI: 10.1002/agr.21396.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Yue, C., Gallardo, R.K., Luby, J., Rihn, A., McFerson, J., McCracken, V., Oraguzie, N., Weebadde, C., Sebolt, A., and A. Iezzoni. 2014. An investigation of United States tart and sweet cherry fruit producers trait prioritizationevidence from audience surveys. HortScience 49:931-947.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Clark, M.D., V.G.M. Bus, J.J. Luby, J.M. Bradeen. 2014. Characterization of the defense response to Venturia inaequalis in Honeycrisp apple, its ancestors, and progeny. Euro. J. Plant Pathology. Eur J Plant Path 140:69-81.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Clark, M.D., C.A. Schmitz, U.R. Rosyara, J.J. Luby, J.M. Bradeen. 2014. A consensus Honeycrisp apple (Malus � domestica) genetic linkage map from three full-sib progeny populations. Tree Genetics & Genomes 10:627-639.
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Yue, C., R.K. Gallardo, J. Luby, A. Rihn, J.R. McFerson, V. McCracken, V. Whitaker, C. Finn, J. Hancock, C. Weebadde, A. Sebolt, A. Iezzoni. 2014.An investigation of United States strawberry producers trait prioritization  evidence from audience surveys. HortScience. 49:188-193.
• Type: Conference Papers and Presentations Status: Submitted Year Published: 2014 Citation: Martinson, TE*, Luby, JJ,, Gartner, W,, Mansfield, AK,, Dharmadhikari, M, Domoto, P. 2014. The Northern Grapes Project: Integrating viticulture, enology, and marketing of new cold-hardy wine grape cultivars in the Midwest and Northeast US. International Horticulture Congress 2014. Brisbane, Australia.
• Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Luby, JJ*, Hemstad, PR, Cook, KL, Smith, NW, Teh, SL, Haggerty, LL, Hegeman, AD. 2014. Breeding and performance of Vitis riparia-based cold climate wine grape cultivars at the University of Minnesota. International Horticulture Congress 2014. Brisbane, Australia.
• Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Li, Y. Gallardo, R. K. McCracken, V., Yue, C., Luby, J. McFerson, J. R. 2014. How does the revelation of previous bid affect new bid? Agricultural and Applied Economics annual conference, Minneapolis, MN, July 27-29, 2014.
• Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Iezzoni, A, Peace, C, Bassil, N, Coe, M, Fazio, G, Gallardo, K, Gasic, K, Luby,J*, Main, D, McFerson, J, van de Weg, E, Weebadde, C. 2014.Where are we now as we merge genomics into plant breeding and what are our limitations? International Horticulture Congress 2014. Brisbane, Australia.
• Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Hardner, CM*, Kumar, S, Peace, C, Luby, J, Evans, K. 2014.RECONSTRUCTING Relationship .atrices from dense SNP arrays for the prediction of genetic potential in unreplicated multilocation field trials of apple progeny. International Horticulture Congress 2014. Brisbane, Australia.
• Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Li, Y., Yue, C., Gallardo, R. K. McCracken, V., Luby, J. McFerson, J. R. 2014. Estimating market equilibrium values of fruit traits for peach and sweet cherry using choice experiments with consumers and producers. American Society for Horticultural Science Annual Conference, Orlando,FL. HortScience 44:S177-S178.
• Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Clark M*, Howard N, Schmitz C, Guan Y, Orcheski B, Verma S, Brown S, Evans K, Peace C, and J Luby. Dissecting the QTL dynamics of harvest date in apple (Malus x domestica). 7th International Rosaceae Genomics Conference, Seattle, June 2014.
• Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Howard N*, Clark M, Schmitz C, Guan Y, Orcheski B, Verma S, Brown S, Evans K, Peace C, and Luby J. 2014. QTL mapping of soft scald in the RosBREED apple germplasm set. 7th International Rosaceae Genomics Conference, Seattle, June 2014.
• Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Peace C*, Luby J, Iezzoni A, Verma S, Clark M, Schmitz C, Sandefur, P, Brown S, van de Weg E, and Evans K. 2014. Exploiting the genetics of the top of chromosome 16 for apple for breeding. 7th International Rosaceae Genomics Conference, Seattle, June 2014.
• Type: Theses/Dissertations Status: Published Year Published: 2014 Citation: Clark, M. 2014. Characterizing the host response and genetic control of resistance in 'Honeycrisp' to apple scab (Venturia inaequalis. PhD Dissertation. University of Minnesota

Progress 01/01/13 to 09/30/13

Outputs
Target Audience: The target audience for new varieties of fruit crops is US producers and ultimately fruit consumers. Numerous fruit varieties from this project were produced by fruit producers during this reporting period. This includes apples (Honeycrisp, Minnewashta (Zestar! brand), Minneiska (SweeTango brand), Wildung (SnowSweet brand), and Frostbite), grapes (Frontenac, Frontenac gris, Marquette, and La Crescent), blueberries (Northblue, St. Cloud, Polaris, Chippewa, Superior, and others), and strawberries (Mesabi, Itasca and Winona). The Honeycrisp apple has had a large impact on the produciton and profitability of the US apple industry as it is produced in every apple producing region. The 2012 Honeycrisp crop was estimated as at least 6 million bushels with a farmgate value of at least $300 million. These 6 million bushels provided over 400 million apple fruits for the nutrition and delight of US consumers. The target audience for new knowledge in genetics, breeding and selection of fruit crops is primarily other public and private sector scientists involved in similar activities. These audiences were reached via publications and presentations at scientific meetings. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Three MS students were trained under the project during the reporting period (David Munter, Cari Schmitz and Luke Haggerty). Two students (Haggerty and Schmitz) completed their degrees during the period. Three PhD studentswere trained under the project during the reporting period (Nicholas Howard, Soon Li Teh, and Matthew Clark). Graduate students Clark and Schmitz attended and presented their research at the Plant and Animal Genome Conference, San Diego, Jan 2013. Soon Li Teh attended meetings of the American Society for Horticutlural Science, Palm Desert, CA, July 2013. How have the results been disseminated to communities of interest? Cultivars have been made available to fruit producers through commercial nurseries. Knowledge developed toward DNA marker assisted selection has been made available in scientific publications and presentations at scientific meetings. Graduate students trained in the project have taken professional positions. What do you plan to do during the next reporting period to accomplish the goals? Obj. 1 Crossing will continue in apples and grapes. Evaluation of selections will continue in apples, grapes, and berry crops. Obj 2 Inheritance of apple scab infections and post harvest fruit disorders in progeny of Honeycrisp apple will be determined so that resistance loci linked to DNA markers can be used for selection. Obj 3 Three PhD students and 1 MS student will continue their training and education.

Impacts
What was accomplished under these goals? Impact. The ultimate impact of this project is through the development and introduction of new fruit varieties that are available to US producers and to consumers as a nutritious and delightful dietary component. Numerous fruit varieties produced from this project are widely grown regionally and nationally. This includes apples (Honeycrisp, Minnewashta (Zestar! brand), Minneiska (SweeTango brand), Wildung (SnowSweet brand), and Frostbite), grapes (Frontenac, Frontenac gris, Marquette, and La Crescent), blueberries (Northblue, St. Cloud, Polaris, Chippewa, Superior, and others), and strawberries (Mesabi, Itasca and Winona). The Honeycrisp apple has had a large impact on the produciton and profitability of the US apple industry as it is produced in every apple producing region. The 2012 Honeycrisp crop was estimated as at least 6 million bushels with a farmgate value of at least $300 million. These 6 million bushels provided over 400 million apple fruits for the nutrition and delight of US consumers. Grape cultivars produced by the project have spawned a cold climate grape and wine industry with important agritourism impact in the midwestern and eastern US that was estimated at over 3,000 acres of grape production and over 300 wineries by a baseline survey that was part of the Northern Grapes Projet partially funded by the USDA-Speciality Crop Research Initiative. As a result of genetic testing in the University of Minnesota apple breeding program: ? A set of parents for crossing was chosen (out of 150 prospective parents) partly based on the results of DNA diagnostic tests that predicted the potential to transmit red skin color, bitter pit resistance, acidity, crispness, storage potential related to ethylene production, and resistance to apple scab disease. ? The power of marker-assisted parent selection is apparent in the following example: Crosses planned in 2012 using only marker-assisted parent selection for skin color saved the University of Minnesota apple breeding program approximately $20,000 in costs of caring for seedlings in the breeding orchard that have no commercial potential due to undesirable skin color. ? Between May and July 2013 about 1,600 seedlings were screened with DNA tests for crispness, skin color, storage potential and apple scab disease at a cost of $5,000. Approximately 900 seedlings were culled based on the results of the genetic tests. Our cost for carrying a seedling to fruiting is about $20; therefore, this culling yielded a net savings of about $13,000. Objective 1. In apple,45crosses were made in 2013 producing7659seeds. From 2012 crosses,1060seedlings were discarded using marker assisted selection and2458seedlings were grafted in the orchard for first evaluation. Approximately 120 selections are in second test phase and9new selections were made in 2012. (1754 trees were discarded from seedling evaluation blocks). Two selections are in advanced testing at sites in several states across the US. In grape, 33 crosses were made in 2012 producing 3213 seeds. From 2011 crosses, 4377 seeds were produced and 2907 seedlings were planted in the disease screening nursery for initial evaluation. Following screening in the 2011 nursery, 464 seedlings from 2010 crosses were planted in the vineyard in 2012. Approximately 75 selections are in second test phase and 4 new selections were made in 2012. In addition, 10 rootstock selections are in second test and 7 rootstock selections were grafted to Marquette and planted to the vineyard in 2009 and 2010. In sweet cherry, 139 seedlings from 11 crosses were planted. From the cooperative primocane fruiting blackberry breeding program with the University of Arkansas, 38 new selections were made from seedlings planted in 2010, 2011, and 2012. These will be added to 25 selections currently in second test. In strawberry, 5 selections were tested in replicated yield trials at 2 sites in MN. In blueberry, approximately 200 selections are being evaluated in second test and 12 selections in yield trials. Objective 2. Develop tools and knowledge base of phenotype and genotype information for critical traits to enable DNA marker assisted breeding for critical traits in apple and grape. We will focus on 2a) traits related to fruit quality and apple scab resistance in apple and 2b) traits related to fruit quality and climate adaptation in grape. Outputs will include phenotype and genotype information needed to perform DNA marker assisted breeding. In grape, approximately 500 individuals from five mapping populations were genotyped for SNP markers. Phenotype data were collected for powdery mildew, foliar phylloxera and fruit color to facilitate mapping of markers for these traits as part of the Vitisgen project sponsored in part by the USDA-Specialty Crops Research Initiative. DNA tests were developed to predict apple skin color amount, fruit firmness, crispness, juiciness, acidity, and storability. These new genetic tests enable apple breeders to select the best parents to combine and the best seedlings to advance, reducing the need to grow out and sort through thousands of seedlings with unacceptable fruit quality. Tests were used in 2013 to select parents for crossing and to cull Objective 3. Three PhD and three MS students were trained and educated during this period as part of the project. Two MS students completed their theses and degrees.

Publications

• Type: Journal Articles Status: Published Year Published: 2012 Citation: Gallardo, R.K., D. Nguyen, V. McCracken, C. Yue, J. Luby, and J.R. McFerson. 2012. An Investigation of trait prioritization in rosaceous fruit breeding programs. HortScience 47:771-776.
• Type: Journal Articles Status: Published Year Published: 2012 Citation: Yue, C., R.K. Gallardo, V. McCracken, J. Luby, J. McFerson, L. Liu and A. Iezzoni. 2012. Technical and Socio-Economic challenges to setting and implementing priorities in North American rosaceous fruit breeding programs. HortScience 47:1320-1327.
• Type: Journal Articles Status: Published Year Published: 2013 Citation: Schmitz, C.A., M.D. Clark, J.J. Luby, J.M. Bradeen, Y. Guan, K. Evans, B. Orcheski, S.K. Brown, S. Verma, C. Peace. Fruit texture phenotypes of the RosBREED U.S. apple reference germplasm set. 2013. HortScience 48:296-303.
• Type: Journal Articles Status: Published Year Published: 2013 Citation: Tong, C.B.S, S.J. McKay, J.J. Luby, R. Beaudry, C. Contreras, J.F. Nock and C.B. Watkins. 2013. Using mixed-effects models to estimate effects of harvest date and its interactions with postharvest storage regimes on apple fruit firmness. J. Hort. Sci.Biotech 88:29-36.
• Type: Journal Articles Status: Published Year Published: 2013 Citation: Yue, C., R.K. Gallardo, J. Luby, A. Rihn, J.R. McFerson, V. McCracken, D. Bedford, S. Brown, K. Evans, C. Weebadde, A. Seybolt. 2013. An investigation of United States apple producers trait prioritization  evidence from audience surveys. HortScience 48:1378-1384.
• Type: Journal Articles Status: Accepted Year Published: 2014 Citation: Yue, C., R.K. Gallardo, J. Luby, A. Rihn, J.R. McFerson, V. McCracken, V. Whitaker, C. Finn, J. Hancock, C. Weebadde, A. Sebolt, A. Iezzoni. An investigation of United States strawberry producers trait prioritization  evidence from audience surveys. HortScience. Accepted.
• Type: Journal Articles Status: Accepted Year Published: 2014 Citation: Clark, M.D., C.A. Schmitz, U.R. Rosyara, J.J. Luby, J.M. Bradeen. A consensus Honeycrisp apple (Malus � domestica) genetic linkage map from three full-sib progeny populations. Tree Genetics & Genomes. Accepted.
• Type: Journal Articles Status: Submitted Year Published: 2014 Citation: Peace, C.P., J.J. Luby, W.E. van de Weg, M.C.A.M Bink, A.F.Iezzoni. A strategy for developing representative germplasm sets for systematic QTL validation, demonstrated for apple, peach, and sweet cherry. Tree Genetics & Genomes. Submitted.
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Hardner, CM, C Peace, J Luby, K Evans. 2013. Prediction of genetic potential of candidate apple cultivars for fruit quality from unreplicated multi-location field trials. American Society for Horticultural Science Annual Conference, Palm Desert, CA. HortScience 48:S154
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Carrillo, L., Gallardo, K., Yue, C., McCracken, V., Luby, J., McFerson, J., and Hanrahan, I. 2013. Relevance of Apple Quality Traits for Consumers. American Society for Horticultural Science Annual Conference, Palm Desert, CA. HortScience 48:S229
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Verma, S., Schmitz, C., Clark, M., Guan, Y., Orcheski, B., Harshman, J., Evans, K., Brown, S., McFerson, J., Bassil, N., Rosyara, U., Bink, M., Luby, J., van de Weg, E., Iezzoni, A., and Peace, C. 2013. Genome-wide QTL Analyses Uncovers SNP Marker-based Functional Alleles for Apple Fresh Sensation Traits. American Society for Horticultural Science Annual Conference, Palm Desert, CA. HortScience 48:S156
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Guan, Y., Schmitz, C., Clark, M., Orcheski, B., Luby, J., Brown, S., Peace, C., Rudell, D., and Evans, K. 2013. Phenotypic Diversity of Individual Sugars, Soluble Solids Content, and Acidity in Rosbreed Apple Germplasm. American Society for Horticultural Science Annual Conference, Palm Desert, CA. HortScience 48:S387
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Clark, M.D., C. Schmitz, U. Rosyara, J. luby, J. Bradeen. 2013. A high-resolution SNP linkage map of a Honeycrisp apple (Malus x domestica) progeny. International Plant & Animal Genome XXI. San Diego, CA #P0415.
• Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2013 Citation: Guan, Y., K. Evans, C. Peace, J. Luby, S. Brown, C. Schmitz, M. Clark, B. Orcheski, S. Verma, D. Rudell, J. Tangern, and A. Iezzoni. 2013. Phenotypic diversity and QTL detection of individual sugars in RosBREED Apple Germplasm. International Plant & Animal Genome XXI. San Diego, CA #P1032.
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Peace, C.*, Bassil NV, Coe, M., Fazio, G., Gallardo, RK, Gasic, K., Luby, J.J., Main, D., McFerson, J., Weebadde, C., van de Weg, W.E., Yue, C., Iezzoni, A. 2013. Marker-assisted breeding in Apple, peach, and cherry targets valuable functional alleles. International Plant & Animal Genome XXI. San Diego, CA #W311.
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Hyma, K., Sun, Q., Mitchell, S.E., Acharya, C., Londo, J., Cousins, P., Fennell, A., Hwang, C-F., Lu, J. Luby, J., Ramming, D.W., Reisch, B., Cadle-Davidson, L.E. 2013. VitisGen: Accelerating grape cultivar improvement. International Plant & Animal Genome XXI. San Diego, CA #W394.
• Type: Theses/Dissertations Status: Published Year Published: 2013 Citation: Schmitz, C.M. 2013. Enabling marker-assisted breeding for fruit texture traits in progeny of the apple cultivar Honeycrisp. MS Thesis. University of Minnesota.
• Type: Theses/Dissertations Status: Published Year Published: 2013 Citation: Haggerty, L.L. Ripening profile of grape berry acids and sugars in University of Minnesota wine grape cultivars, select Vitis vinifera, and other hybrid cultivars. MS Thesis. University of Minnesota.

Progress 01/01/12 to 12/31/12

Outputs
OUTPUTS: In apple, 20 crosses were made in 2012 producing 2515 seeds. From 2011 crosses, 3903seeds were produced and 2555 seedlings were grafted in the orchard for first evaluation. Approximately 120 selections are in second test phase and 13 new selections were made in 2012. Two selections are being sent to sites around the US for national testing. In grape, 33 crosses were made in 2012 producing 3213 seeds. From 2011 crosses, 4377 seeds were produced and 2907 seedlings were planted in the disease screening nursery for initial evaluation. Following screening in the 2011 nursery, 464 seedlings from 2010 crosses were planted in the vineyard in 2012. Approximately 75 selections are in second test phase and 4 new selections were made in 2012. In addition, 10 rootstock selections are in second test and 7 rootstock selections were grafted to Marquette and planted to the vineyard in 2009 and 2010. In sweet cherry, 139 seedlings from 11 crosses were planted. From the cooperative primocane fruiting blackberry breeding program with the University of Arkansas, 335 seedlings were planted in 2012 and 14 new selections were made from seedlings planted in 2009, 2010 and 2011. These will be added to 36 selections currently in second test. In strawberry, 5 selections were tested by commercial nurseries for possible commercialization. In blueberry, approximately 200 selections are being evaluated in second test and 12 selections in yield trials. Fruit samples of 16 grape cultivars were collected at 6 maturity stages in 2011 and 2012 to determine profiles of acids, sugars and anthocyanins during ripening. Accumulated Growing Degree Days (base 50F) appears to be highly predictive of optimal harvest time in Minnesota with 2500 to 2725 GDDs needed to fully ripen cold climate wine grape varieties to peak maturity in east central Minnesota. A high-resolution consensus linkage map was constructed using a Honeycrisp x MN1764 progeny population (n = 119). The International RosBREED SNP Consortium (IRSC) apple 8K SNP array v1provided 1,952 (24.8 percent) high quality, polymorphic SNP markers which were assigned to the 17 linkage groups known in Malus. The length of the map was approximately 1329 centimorgans (cM) with an average density of 0.64 cM per marker. The largest gap in the linkage map where no markers mapped is 21.9 cM. Four other regions had gaps larger than 10 cM. The development of a 'Honeycrisp' linkage map based on the IRSC snp array has facilitated the detection and validation of QTL in breeding populations using FlexQTL (pedigree based ) and in bi-parental mapping populations. Honeycrisp appears to have genes on two chromosomes that condition some resistance to apple scab disease and at least four chromosomes appear to have genes that contribute to desirable texture (crispness, juiciness). PARTICIPANTS: Project personnel: James Luby, PI; David Bedford, Scientist; Peter Hemstad, Scientist; Matt Clark and Soon Li Teh, Graduate Research Assistants pursuing Ph.D.; Luke Haggerty, Cari Schmitz, Graduate Research Assistants pursuing MS; Alex Bedker, John Tillman, Undergraduate Research Assistants, Jennifer Bradley, Research Plot Technician, Andreia Suzukawa, MAST agricultural exchange student; Ken Mullin and Robert Guthrie, Volunteers. Collaborators: University of Minnesota Department of Horticultural Science: Emily Hoover, Cindy Tong, Chengyan Yue, Kathryn Cook; Dept. of Plant Pathology James Bradeen; Dept. of Food Science Zata Vickers; James Hancock, Amy Iezzoni, Cholani Weebadde, Michigan State University, Dept. of Horticulture; Anne Fennell, South Dakota State University, Dept. of Horticulture; Lance Cadle-Davidson, David Ramming, Jason Londo, USDA-ARS; Sue Gardiner and Vincent Bus, Plant and Food Research, New Zealand; Susan Brown, Bruce Reisch, Anna Katharine Mansfield, Tim Martinson, Cornell Univ; Douglas Shaw, Tom Gradziel, Carlos Crisosto, Univ. of California-Davis; Cameron Peace, Kate Evans, Nnadozie Oraguzie, Karina Gallardo, Dorrie Main, Washington State Univ.; Chad Finn and Nahla Bassil, USDA-ARS, Corvallis OR; Thomas Davis, Univ. of New Hampshire; David Byrne, Texas AandM Univ.; Eric Van de Weg, Plant Research International, Netherlands TARGET AUDIENCES: The target audience for new varieties of fruit crops is primarily producers in the midwestern and eastern US with climates similar to Minnesota and ultimately fruit consumers in the US. The target audience for new knowledge in genetics, breeding and selection of fruit crops is primarily other public and private sector scientists involved in similar activities. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
New varieties of apples, grapes, blueberries, strawberries, and other fruits developed under this project are benefiting fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers are benefiting from their superior eating qualities and improved health-related traits. Knowledge developed in the genetics of fruit crops including development of DNA markers for use in marker-aided breeding should improve the efficiency of fruit breeding programs and increase the probability of obtaining new fruit varieties with desired features.

Publications

• Evans, K., Y. Guan, J. Luby, M. Clark, C. Schmitz, S. Brown, B. Orcheski, C. Peace, E. van de Weg, A. Iezzoni. 2012. Large-scale standardized phenotyping of apple in RosBREED. Acta Hort 945:233-238.
• Luby, J.J. and D.S. Bedford. 2012. Apples. In: (J.R. Clark and C.E. Finn, eds.) Register of New Fruit and Nut Cultivars List 45. HortScience 46:536-538.
• Yao, S., J. Luby, and K. Hummer. 2012. Cold hardiness and foliar disease resistance of North American and Asian Fragaria. J. Amer. Pom. Soc. 66:46-55.
• Yue, C., R.K. Gallardo, V. McCracken, J. Luby, J. McFerson, L. Liu and A. Iezzoni. 2012. Technical and Socio-Economic challenges to setting and implementing priorities in North American rosaceous fruit breeding programs. HortScience 47:1320-1327.
• Gallardo, R.K., D. Nguyen, V. McCracken, C. Yue, J. Luby, and J.R. McFerson. 2012. An Investigation of trait prioritization in rosaceous fruit breeding programs. HortScience 47:771-776.

Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: Crosses were made in apple and grape and selections were made in apple, grape, and blackberry. In apple, 25 crosses were made producing 3903 seeds. From 2010 crosses, 5612 seeds were produced and 4476 seedlings were grafted in the orchard for first evaluation. Approx 120 selections are in second test phase and 15 new selections were made in 2011. In grape, 38 crosses were made producing 4377 seeds. From 2010 crosses, 5462 seeds were produced and 2888 seedlings were planted in the disease screening nursery for initial evaluation. 419 seedlings from 2009 crosses were planted in the vineyard following screening in the 2010 nursery. Approx 75 selections are in second test phase and 8 new selections were made in 2011. From the cooperative primocane fruiting blackberry breeding program with the Univ of Arkansas, 704 seedlings were planted in 2011 and 8 new selections were made from seedlings planted in 2009 and 2010 including 3 thornless selections. These will be added to 28 selections that are in second test. In strawberry, 5 selections were tested by commercial nurseries for possible commercialization. In blueberry, approximately 200 selections are being evaluated in second test and 12 selections in yield trials. Fruit samples of 16 grape genotypes were collected at 6 maturity stages in 2011 to determine profiles of acids, sugars and anthocyanins during ripening. Over 150 apple lines harvested in 2010 were assayed following storage for fruit texture traits by instrumental and sensory analysis between January and March 2011 as part of a project to identify functional alleles of candidate genes and quantitative trait loci for these traits. Approximately 350 lines were harvested in 2011 and evaluated for fruit quality traits as part of the USDA-SCRI RosBREED project. Leaf samples from these lines were collected and sent to USDA-ARS Corvallis, Oregon for genome scanning to develop markers for quantitative trait loci for apple fruit quality traits. This study characterizes variability and estimates heritability for several apple fruit texture traits within a large breeding population over several years. In a separate study,five full-sib families, all sharing Honeycrisp as a common parent, were assayed with respect to crispness, firmness, and juiciness using sensory evaluation panels and total work required to fracture tissue using instrumental methods. The incomplete block design of the sensory panels, coupled with best linear unbiased prediction, facilitated the evaluation of a large number of genotypes with small numbers of fruit per genotype, while accounting for individual sensory panelist effects. Broad-sense heritability estimates exceeded 0.70 for all four traits. Principal component analysis, applied to the phenotypic data, characterized Honeycrisp as having average crispness and low firmness (53rd percentile relative to its offspring), but also as being a relatively extreme example of high juiciness and low work to fracture (1st percentile). The improved characterization of desired fruit texture phenotypes and the high levels of broad-sense heritability provide valuable tools for the further development of new, high quality apple cultivars. PARTICIPANTS: Project personnel: James Luby, PI; David Bedford, Scientist; Peter Hemstad, Scientist; Steven McKay, Post Doctoral; Matt Clark, Graduate Research Assistant, pursuing Ph.D.; Luke Haggerty, Cari Schmitz, Graduate Research Assistants, pursuing MS; Alex Bedker, Heath Bredeson, Undergraduate Research Assistants, Jennifer Bradley, Research Plot Technician, Andreia Suzukawa, MAST agricultural exchange student; Ken Mullin and Bob Guthrie, Volunteers. Collaborators: University of Minnesota Department of Horticultural Science: Emily Hoover, Cindy Tong, Chengyan Yue, Kathryn Cook; Dept. of Plant Pathology James Bradeen; Dept. of Food Science Zata Vickers; James Hancock, Amy Iezzoni, Cholani Weebadde, Michigan State University, Dept. of Horticulture; Anne Fennell, South Dakota State University, Dept. of Horticulture; Amanda Garris, Chris Owens, USDA-ARS,Geneva, NY; Sue Gardiner and Vincent Bus, Plant and Food Research, New Zealand; Susan Brown, Anna Katharine Mansfield, Tim Martinson, Cornell Univ; Douglas Shaw, Tom Gradziel, Carlos Crisosto, Univ. of California-Davis; Cameron Peace, Kate Evans, Nnadozie Oraguzie, Karina Gallardo, Washington State Univ.; Chad Finn and Nahla Bassil, USDA-ARS, Corvallis OR; Thomas Davis, Univ. of New Hampshire; David Byrne, Texas AandM Univ.; Eric Van de Weg, Plant Research International, Netherlands; Jasper Rees, Univ. of Western Cape, South Africa; Daleen Van Dyk, Univ. of Pretoria, South Africa; Daniel Sargent, East Malling Research, UK TARGET AUDIENCES: The target audience for new varieties of fruit crops is primarily producers in the midwestern and eastern US with climates similar to Minnesota and ultimately fruit consumers in the US. The target audience for new knowledge in genetics, breeding and selection of fruit crops is primarily other public and private sector scientists involved in similar activities. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
New varieties of apples, grapes, blueberries, strawberries, and other fruits developed under this project are benefiting fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers are benefiting from their superior eating qualities and improved health-related traits. Knowledge developed in the genetics of fruit crops including development of DNA markers for use in marker-aided breeding should improve the efficiency of fruit breeding programs and increase the probability of obtaining new fruit varieties with desired features.

Publications

• Telias, A., J. M. Bradeen, J. J. Luby, A.C. Allan, E.E. Hoover. 2011.Towards a healthier and more attractive apple: Regulation of anthocyanin accumulation. Horticultural Reviews 38:357-391.
• McKay, S.J., J.M. Bradeen, and J.J. Luby. 2011. Prediction of Genotypic Values for Apple Fruit Texture Traits in a Breeding Population Derived from Honeycrisp.J. Amer. Soc. Hort. Sci. 136:408-414.
• Schouten, H.J., W.E. van de Weg, J. Carling, S. Ali Khan, S.J. McKay, M. P.W. van Kaauwen, A.H.J. Wittenberg, H.J.J. Koehorst-van Putten, Y. Noordijk, Z. Gao, D.J.G. Rees, M.M. Van Dyk, D. Jaccoud, M. J. Considine, A. Kilian 2011. Diversity arrays technology (DArT) markers in apple for genetic linkage maps. Mol. Breeding DOI 10.1007/s11032-011-9579-5
• McKay, S.J. 2010. The Genetic Dissection of Fruit Texture Traits in the Apple Cultivar Honeycrisp. Ph.D. Dissertation. University of Minnesota.
• Luby, J et al. 2010 Small Fruit Variety Trials in Minnesota. Proc. 2011 Upper Midwest Fruit and Vegetable Conference. Pp. 30-40.

Progress 01/01/10 to 12/31/10

Outputs
OUTPUTS: Crosses were made in apple and grape and selections were made in apple, grape, and blackberry. In apple, 24 crosses were made producing 5612 seeds. From 2009 crosses, 1799 seeds were produced and 1362 seedlings were grafted in the orchard for first evaluation. Approximately 120 selections are in second test phase and 7 new selections were made in 2010. In grape, 37 crosses were made producing 5462 seeds. From 2009 crosses, 6138 seeds were produced and 3284 seedlings were planted in the disease screening nursery for first evaluation. 594 seedlings from 2008 crosses were planted in the vineyard following screening in the 2009 nursery. Approximately 70 selections are in second test phase and 6 new selections were made in 2010. In addition, 10 rootstock selections are in second test and 7 rootstock selections were grafted to Marquette and planted to the vineyard in 2009 and 2010. From the cooperative primocane fruiting blackberry breeding program with the University of Arkansas, 555 seedlings were planted in 2010 and 6 new selections were made from seedlings planted in 2008 and 2009 including 3 thornless selections. These will be added to 39 selections that are in second test. In strawberry, 5 selections were tested by commercial nurseries for possible commercialization. In blueberry, approximately 200 selections are being evaluated in second test and 12 selections in yield trials. Grapevines of MN 1189, MN1200, MN1220, MN1235 and MN1258 were distributed to test sites in the NE 1020 project to determine their potential regional adaptation and performance. Fruit samples of 16 grape genotypes were collected at 5 maturity stages in 2010 to determine profiles of acids, sugars and anthocyanins during ripening. At Grand Rapids, MN, 34 strawberry germplasm accessions from the USDA-National Clonal Germplasm Repository were evaluated for winter injury, disease resistance, and fruit traits. Fragaria iinumae was exceptionally cold tender and Fragaria nipponica, orientalis and virginiana accessions were quite cold hardy as was FRA 1871.001 of Fragaria chiloensis. Over 200 apple lines harvested in 2009 were assayed following storage for fruit texture traits by instrumental and sensory analysis between January and March 2010 as part of a project to identify functional alleles of candidate genes and quantitative trait loci for these traits. Approximately 150 lines were harvested in 2010 and evaluated for fruit quality traits as part of the USDA-SCRI RosBREED project. Leaf samples from these lines were collected and sent to USDA-ARS Corvallis, Oregon for genome scanning to develop markers for quantitative trait loci for apple fruit quality traits. As part of a USDA-SCRI planning grant, a workshop of approximately 50 persons including extension and research personal and growers from several northeastern and midwestern states was held in Bloomington, Minnesota to identify and coordinate research and extension needs in the emerging cold climate grape and wine industry emerging in these regions. PARTICIPANTS: Project personnel: James Luby, PI; David Bedford, Scientist; Peter Hemstad, Scientist; Steven McKay, Matt Clark, Graduate Research Assistants, pursuing Ph.D.; Luke Haggerty, Cari Schmitz, Graduate Research Assistants, pursuing MS; Megan Mathey, Ben Tietge, Heath Bredeson, Undergraduate Research Assistants, Jennifer Bradley, Research Plot Technician, Luis Gomez Zelaya, MAST agricultural exchange student; Ken Mullin and Bob Guthrie, Volunteers. Collaborators: University of Minnesota Department of Horticultural Science: Emily Hoover, Cindy Tong, Chengyan Yue, Kathryn Cook; Dept. of Plant Pathology James Bradeen; Dept. of Food Science Zata Vickers; James Hancock, Amy Iezzoni, Cholani Weebadde, Michigan State University, Dept. of Horticulture; Anne Fennell, South Dakota State University, Dept. of Horticulture; Amanda Garris, Chris Owens, Phil Forsline, USDA-ARS,Geneva, NY; Sue Gardiner, HortResearch, New Zealand Vincent Bus, Plant and Food Research, New Zealand; Susan Brown, Anna Katharine Mansfield, Tim Martinson, Cornell Univ; Douglas Shaw, Tom Gradziel, Carlos Crisosto, Univ. of California-Davis; Cameron Peace, Kate Evans, Nnadozie Oraguzie, Karina Gallardo, Washington State Univ.; Chad Finn and Nahla Bassil, USDA-ARS, Corvallis OR; Thomas Davis, Univ. of New Hampshire; David Byrne, Texas AandM Univ.; Eric Van de Weg, Plant Research International, Netherlands; Jasper Rees, Univ. of Western Cape, South Africa; Daleen Van Dyk, Univ. of Pretoria, South Africa; Daniel Sargent, East Malling Research, UK. TARGET AUDIENCES: The target audience for new varieties of fruit crops is primarily producers in the midwestern and eastern US with climates similar to Minnesota and ultimately fruit consumers in the US. The target audience for new knowledge in genetics, breeding and selection of fruit crops is primarily other public and private sector scientists involved in similar activities. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
New varieties of apples, grapes, blueberries, strawberries, and other fruits developed under this project are benefiting fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers are benefiting from their superior eating qualities and improved health-related traits. Knowledge developed in the genetics of fruit crops including development of DNA markers for use in marker-aided breeding should improve the efficiency of fruit breeding programs and increase the probability of obtaining new fruit varieties with desired features.

Publications

• Iezzoni, A.. C. Weebadde, J. Luby, C. Yue, E. van de Weg, , G. Fazio, ,D. Main, C. Peace, N.Bassil, and J. McFerson. 2010 RosBREED: Enabling Marker-Assisted Breeding in Rosaceae. Acta Hort 859:389-394.
• Meyer M.H., S. Hokanson, S. Galatowitsch, J. Luby. 2010. Public Gardens: Fulfilling the University's Research Mission. HortTechnology 20:522-527.
• Luby, J.J. and D.S. Bedford. 2010. Apples. In: (J.R. Clark and C.E. Finn, eds.) Register of New Fruit and Nut Cultivars List 45. HortScience 45:716-719.
• Bus V, E. Rikkerink, H.S. Aldwinckle, V. Caffier, C.E. Durel,S. Gardiner, C. Gessler, R. Groenwold, F. Laurens, B.L. Cam, J. Luby, B. Meulenbroek, M. Kellerhals, L. Parisi11, A. Patocchi, K. Plummer, H.J. Schouten, S. Tartarini, W.E. van de Weg. 2009. A proposal for the nomenclature of Venturia inaequalis races. Acta Hort 814:739-746
• Luby, J., D. Bedford, S. Yao, K. Mann, P. Johnson, S. Poppe. 2010 2009 Small Fruit Variety Trials in Minnesota. Proc. 2010 Upper Midwest Fruit and Veg Conference. Pp. 30-44.
• Luby, J., R. Guthrie, E. Theship-Rosales. 2010. Introducing cold hardy kiwifruit to Minnesota. Minn. Dept. of Agric. Greenbook 2010. Pp.21-25.
• Hancock, J., C. Finn, J. Luby, A. Dale, P. Callow and S. Serce. 2010. Reconstruction of the strawberry, Fragaria x ananassa, using native genotypes of F. virginiana and F. chiloensis. HortScience 45:1006-1013.

Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: Crosses were made in apple and grape and selections were made in apple, grape, and blackberry. In apple, 14 crosses were made producing 1799 seeds. From 2008 crosses, 4071 seeds were produced and 3664 seedlings were planted in the orchard for first evaluation. Approximately 128 selections are in second test phase and 13 new selections were made in 2009. In grape, 39 crosses were made producing 6162 seeds. From 2008 crosses, 3556 seeds were produced and 2586 seedlings that were planted in the disease screening nursery for first evaluation. Approximately 70 selections are in second test phase and 6 new selections were made in 2009. In addition, 10 rootstock selections are in second test and 7 rootstock selections were grafted to Marquette and planted to the vineyard in 2009. From the cooperative primocane fruiting blackberry breeding program with the University of Arkansas,290 seedlings were planted in 2009 and 6 new selections were made from seedlings planted in 2008. These will be added to 33 selections that are in second test. In strawberry, 5 selections were distributed to commercial nurseries for possible commercialization. In blueberry, approximately 200 selections are being evaluated in second test and 12 selections in yield trials. The blueberry cultivar Superior (MN 5451) was introduced in 2009. The apple cultivar Minneiska (MN 1914), marketed under the SweeTango trademark, was introduced in 2009. Grapevines of MN 1189, MN1200, MN1220, MN1235 and MN1258 were distributed to test sites in the NE 1020 project to determine their potential regional adaptation and performance. Genetic maps were developed in grape from a cross of Vitis riparia (PI) x Seyval blanc. F2 individuals from the cross were phenotyped for timing of dormancy and acclimation-related traits in the greenhouse and field environments. Separate major quantitative trait loci were identified on linkage groups 11 and 13 for dormancy attained in the greenhouse and field, respectively. Over 200 apple lines from 6 segregating families were assayed for fruit texture traits by instrumental and sensory analysis between August and December 2009 as part of a project to identify functional alleles of candidate genes and quantitative trait loci for these traits. As part of a USDA-SCRI planning grant, a workshop of approximately 50 persons including extension and research personal and growers from several northeastern and midwestern states was held in Burlington Vermont to identify and coordinate research and extension needs in the emerging cold climate grape and wine industry emerging in these regions. PARTICIPANTS: Project personnel: James Luby, PI; David Bedford, Scientist; Peter Hemstad, Scientist; Steven McKay, Graduate Research Assistant, currently pursuing a Ph.D. degree; Matt Clark, Graduate Research Assistant; Megan Mathey and Ben Tietge, Undergraduate Research Assistants, Jennifer Bradley, Research Plot Technician, Luis Gomez Zelaya, MAST agricultural exchange student; Ken Mullin and Bob Guthrie, Volunteers. Collaborators: University of Minnesota Department of Horticultural Science: Emily Hoover, Cindy Tong, Chengyan Yue, Shengrui Yao; Dept. of Plant Pathology James Bradeen Dept. of Food Science Zata Vickers; James Hancock, Amy Iezzoni, Cholani Weebadde, Michigan State University, Dept. of Horticulture; Anne Fennell, South Dakota State University, Dept. of Horticulture; Amanda Garris, Chris Owens, Phil Forsline, USDA-ARS,Geneva, NY; Sue Gardiner, HortResearch, New Zealand Vincent Bus, Plant and Food Research, New Zealand; Susan Brown, Anna Katharine Mansfield, Tim Martinson, Cornell Univ; Douglas Shaw, Tom Gradziel, Carlos Crisosto, Univ. of California-Davis; Cameron Peace, Kate Evans, Nnadozie Oraguzie, Karina Gallardo, Washington State Univ.; Chad Finn and Nahla Bassil, USDA-ARS, Corvallis OR; Thomas Davis, Univ. of New Hampshire; David Byrne, Texas AandM Univ.; Eric Van de Weg, Plant Research International, Netherlands; Jasper Rees, Univ. of Western Cape, South Africa; Daleen Van Dyk, Univ. of Pretoria, South Africa; Daniel Sargent, East Malling Research, UK. TARGET AUDIENCES: The target audience for new varieties of fruit crops is primarily producers in the midwestern and eastern US with climates similar to Minnesota and ultimately fruit consumers in the US. The target audience for new knowledge in genetics, breeding and selection of fruit crops is primarily other public and private sector scientists involved in similar activities. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
New varieties of apples, grapes, blueberries, strawberries,and other fruits developed under this project are benefiting fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers are benefiting from their superior eating qualities and improved health-related traits. Knowledge developed in the genetics of fruit crops including development of DNA markers for use in marker-aided breeding should improve the efficiency of fruit breeding programs and increase the probability of obtaining new fruit varieties with desired features.

Publications

• Yao, S., J.J. Luby, D.K. Wildung. 2009. Strawberry cultivar injury after two contrasting Minnesota winters. HortTechnology 19:803-808. Garris, A., L. Clark, C. Owens, S.J. McKay, J.J. Luby, K. Mathiason, A. Fennell. 2009. Mapping of photoperiod-induced growth cessation in the wild grape Vitis riparia Michx. using microsatellite markers. J. Amer. Soc. Hort. Sci. 134:261-272. Luby, J.J. and D.V. Shaw. 2009. Plant breeders' perspectives on improving yield and quality traits in horticultural food crops. HortScience 44:20-22. Luby, J.J., A. Garris, A.Y. Fennell, S.J. McKay, L. Clark, C. Owens, and K. Mathiason. 2009. Mapping photoperiod-induced growth cessation in the wild grape Vitis riparia Michx. Plant and Animal Genome XVII. Jan 10-14, 2009, San Diego, CA. p. 96. McKay, S.J., Luby, J.J., J.M. Bradeen, J. Carling, and A. Kilian. 2009. QTL mapping for apple fruit texture traits in five 'Honeycrisp'-derived families using DArT markers. Plant and Animal Genome XVII. Jan 10-14, 2009, San Diego, CA. p. 101. Luby, J. Bedford,D.Yao, S. Poppe, S. '2008 Small Fruit Variety Trials in Minnesota.' Proc. 2009 Upper Midwest Fruit and Veg Conference.

Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: Crosses were made in apple and grape and selections were made in apple, grape, and blackberry. MN447, a small apple with an unusual sweet, tropical fruit flavor was introduced and is being sold under the trademark Frostbite. MN 5451 blueberry, a late season selection that has been very productive and hardy in USDA Hardiness Zones 3-4 will be introduced in 2009 as Superior. Five grape selections were propagated for inclusion in trials of NE 1020 collaborators, MN 1189, MN 1200, MN 1220, MN 1235, and MN 1258. Five strawberry selections are being propagated for introduction. Resistance to white pine blister rust in blackcurrants was confirmed in lab tests forseveral selections being tested in the field and a commercial nursery mixup was solved so that disease resistant Consort plants will now be going into the market rather than a disease susceptible unknown type. PARTICIPANTS: Participants David Bedford, Scientist Peter Hemstad, Scientist Steven McKay, Graduate Research Assistant, currently pursuing a Ph.D. degree Collaborators University of Minnesota Department of Horticultural Science Anna Katharine Mansfield, Senior Research Fellow Emily Hoover Cindy Tong Dept. of Plant Pathology James Bradeen Dept. of Food Science Zata Vickers James Hancock, Michigan State University, Dept. of Horticulture Anne Fennell, South Dakota State University,Dept. of Horticulture Chris Owens, USDA-ARS,Geneva NY Phil Forsline, USDA-ARS, Geneva, NY Sue Gardiner, HortResearch, New Zealand Vincent Bus, HortResearch, New Zealand TARGET AUDIENCES: The target audience for new varieties of fruit crops is primarily producers in the midwestern and eastern US with climates similar to Minnesota and ultimately fruit consumers in the US. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
The genetics of disease resistance, winter hardiness, spring bloom date, fruit set, ovule set, fruit size, and photoperiod sensitivity was investigated in crosses between sets of elite selections of F. virginiana and F. chiloensis in Minnesota and Ontario. Progeny means varied considerably for all traits except ovule set. For all other traits, general combining ability was significant for at least one species, while specific combining ability was significant for only gender and spring bloom date. Just as they were in previous crosses with F. ananassa cultivars, the F. virginiana parents High Falls 22 and Montreal River 10 were notable for producing offspring with large fruit and high fertility. Fragaria chiloensis parents exhibited strong combining ability effects for short day-induced flowering and suppressed the expression of day-neutral flowering in these progeny compared to progeny of these F. virginiana in previous crosses with F. ananassa. These results indicate that substantial breeding progress can be made by reconstructing F. ananassa if care is taken to select elite, complimentary genotypes of F. virginiana and F. chiloensis. New varieties of strawberries, apples, blueberries, grapes, and other fruits developed under this project will benefit fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers will benefit from their superior eating qualities and improved health-related traits. Knowledge developed in the genetics of fruit crops should improve the efficiency of fruit breeding programs and increase the probability of obtaining new fruit varieties with desired features.

Publications

• Weebadde, C. K., D. Wang, C.E. Finn, K.S. Lewers, J.J. Luby, J. Bushakra, T.M. Sjulin and J.F. Hancock. 2008. Using a linkage mapping approach to identify QTL for day-neutrality in the octoploid strawberry (Fragaria ananassa Duch ex Rozier). Plant Breeding 127:94-101.
• Burnes, T.A., J.A. Smith, J. J. Luby, and R.A. Blanchette. 2008.Black currant clonal identity and white pine blister rust resistance. HortScience 43:200-202.
• Hancock, J.F., J.J. Luby, S.K. Brown and G.A. Lobos. 2008. Apples. Pp. 1-38. In: J.F. Hancock, ed.) Temperate Fruit Crop Breeding: Germplasm to Genomics. Springer.
• Yao, S. and J. Luby. 2008. Cold hardiness of strawberries after test winter of 2006-07 in Minnesota. HortScience 43:1230.
• Luby, J.J., J. F. Hancock, A. Dale and S. Serce. 2008. Reconstructing Fragaria ananassa utilizing wild F. virginiana and F. chiloensis: Inheritance of winter injury, photoperiod sensitivity, fruit size, female fertility and disease resistance in hybrid progenies. Euphytica 163:57-65.
• Luby, J.J. and D.S. Bedford. 2008. Apples. In: (J.R. Clark and C.E. Finn, eds.) Register of New Fruit and Nut Cultivars. HortScience 43:1322.

Progress 01/01/07 to 12/31/07

Outputs
OUTPUTS: Crosses were made in apple and grape and selections were made in apple, grape, and blackberry. The Wildung apple was introduced. This was tested as MN 1797 and is being marketed under the trademark SnowSweet apple. An application was made for a US Plant Patent for Wildung(MN 1797) apple. It is a hardy, late season apple cultivar with a sweet, rich flavor and white flesh resistant to oxidation. An application was made for a US Plant Patent on MN 1914 apple, an early season selection with very crisp flesh, a balanced flavor, and 2 to 3 months storage capability. MN447, a small apple with an unusual sweet, tropical fruit flavor will be introduced. MN 5451 blueberry, a late season selection that has been very productive and hardy in USDA Hardiness Zones 3-4 will be propagated for introduction. Four grape selections were propagated for inclusion in trials of NE 1020 collaborators, MN 1189, MN 1200, MN 1220, and MN 1235. Five strawberry selections are being propagated for introduction. A major study of variation and relationships among wild strawberry taxa of North and South America based on DNA markers (simple sequence repeats or SSR markers)was completed. DNA was obtained from 111 individuals representing F. chiloensis ssp. pacifica, F. chiloensis ssp. lucida, F. virginiana ssp. virginiana, F. virginiana ssp. glauca, F. virginiana ssp. grayana, and F. virginiana ssp. platypetala from North America, F. chiloensis ssp. chiloensis f. chiloensis and F. chiloensis ssp. chiloensis f. patagonica from South America, F. chiloensis ssp. sandwicensis from Hawaii, as well as F. xananassa ssp. cuneifolia, and F. xananassa ssp. ananassa. A total of 108 bands were scored among all accessions using the five SSR primer pairs, for a mean of 21.6 bands per primer pair with three to eight bands in individual accessions. Cluster analysis and principal coordinate analysis using Jaccard similarity coefficients based on presence or absence of bands supported the separation of F. virginiana and F. chiloensis as distinct species. The various F. virginiana subspecies were not distinguishable. The two South American forms of F. chiloensis ssp. chiloensis are very similar to each other and distinct from the North American subspecies. The F. chiloensis ssp. sandwicensis accessions were distinct from other taxonomic classes. The F. xananassa cultivars clustered most closely with the South American F. chiloensis supporting the origin of F. xananassa primarily from South American rather than North American F. chiloensis. While the North and South American F. chiloensis subspecies should remain separated based on their molecular distinction, consideration should be given to classifying F. chiloensis ssp. pacifica and ssp. lucida as different forma of a single North American F. chiloensis subspecies, rather than as separate subspecies. This is similar to the current classification of the two South American forma of F. chiloensis ssp. chiloensis. Similarly, the F. virginiana subspecies should be reclassified as forms of a single subspecies, F. virginiana ssp. virginiana, rather than separate subspecies. PARTICIPANTS: Participants David Bedford, Scientist Peter Hemstad, Scientist Steven McKay, Graduate Research Assistant, currently pursuing a Ph.D. degree Collaborators University of Minnesota Department of Horticultural Science Anna Katharine Mansfield, Senior Research Fellow Emily Hoover Cindy Tong Dept. of Plant Pathology James Bradeen Dept. of Food Science Zata Vickers James Hancock, Michigan State University, Dept. of Horticulture Anne Fennell, South Dakota State University,Dept. of Horticulture Chris Owens, USDA-ARS,Geneva NY Phil Forsline, USDA-ARS, Geneva, NY Mark Strefeler, Augsburg College Sue Gardiner, HortResearch, New Zealand Vincent Bus, HortResearch, New Zealand TARGET AUDIENCES: The target audience for new varieties of fruit crops is primarily producers in the midwestern and eastern US with climates similar to Minnesota and ultimately fruit consumers in the US.

Impacts
New varieties of strawberries, apples, blueberries, grapes, and other fruits developed under this project will benefit fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers will benefit from their superior eating qualities and improved health-related traits. Knowledge developed in the genetics of fruit crops should improve the efficiency of fruit breeding programs and increase the probability of obtaining new fruit varieties with desired features.

Publications

• Hokanson, K., Smith, M., Connor, A.M, Luby, J.J, and J. Hancock. 2006. Relationships among subspecies of New World octoploid strawberry species, Fragaria virginiana and Fragaria chiloensis, based on SSR marker analysis. Can. J. Bot. 84:1829-1841. Luby, J.J. and D.S. Bedford. 2006. Apples. In: (J.R. Clark and C.E. Finn, eds.) Register of New Fruit and Nut Cultivars List 43. HortScience 41:1101-1103.

Progress 01/01/06 to 12/31/06

Outputs
Crosses were made in apple and grape and selections were made in apple, grape, pear, apricot, blueberry and blackberry. An application was made for a US Plant Patent for Wildung(MN 1797) apple. Wildung(Sharon x Connell Red) is a hardy, late season apple cultivar. The fruit is oblate, moderately firm, and has fine-grained flesh with a sweet, rich flavor. The white flesh is also notably resistant to oxidation when exposed to air. Ripening time is approximately two weeks after Honeycrisp. Fruit size is about 7.1 to 7.9 cm in diameter. Fruit color is 65 to 85 pct red, occasionally with bronze-red tones, over yellow-green. The storage life of refrigerated fruit is 60 to 80 days. Trees bear fruit annually and small, unripe fruit have not been commonly observed. Trees of Wildung are being sold under the trademark SnowSweet apple. An application was made for a US Plant Patent on Marquette (MN 1211) grape and this variety was made available to grape growers. Marquette combines high levels of cold hardiness and disease resistance with excellent red wine quality. Marquette is from a cross between MN 1094 and the French Hybrid Ravat 262. MN 1094 was derived from a complex parentage including V. riparia, V. vinifera, and other Vitis species. Ravat 262 likewise has a complex background, but has the renowned variety Pinot noir as one parent. Marquette has withstood winter temperatures as low as -36 F without serious injury. Resistance to common grape diseases (downy mildew, powdery mildew and black rot), has been very good. Resistance to foliar phylloxera is moderate. The growth habit of Marquette is open and orderly allowing efficient vineyard management and good fruit exposure to the sun to maximize wine quality. Shoots typically have two small to medium clusters per shoot. Bud break is somewhat early, slightly before Frontenac. Marquette ripens in early mid-season, a few days before Frontenac. Marquette yields have been moderate, averaging 4.78 Kg/vine or 3.42 tons/acre. The clusters and berries of Marquette are small to medium in size. Sugar levels have been high, averaging 25.9 degrees brix and average juice pH value has been 3.00. Acid levels have also been higher than most cultivars (12.0 g/l) although substantially lower than that of Frontenac. Blackberry seedlings from 12 crosses and 7 of their parents planted in May 2005 were evaluated for date of first bloom, date of first ripe fruit, and rated for amount of flowering, fruit size, growth habit and vigor. Each cross was represented by 5 seedlings and each parent line by 2 plants in each of 5 blocks. Among the seedlings, date of first bloom varied from 2 Jul to 3 Oct and first ripe fruit from 7 Aug to 15 Oct. Overall in these crosses between primocane-flowering parents, 51 percent of the seedlings exhibited primocane flowering. Individual crosses ranged from 15 to 90 percent of seedlings exhibiting primocane flowering. Variation for time of first bloom and first ripe fruit on primocanes appeared to be greater within crosses than among crosses. Seedlings also exhibited considerable variation for relative fruit size, vigor and growth habit.

Impacts
New varieties of strawberries, apples, blueberries, grapes, and other fruits developed under this project will benefit fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers will benefit from their superior eating qualities and improved health-related traits. Knowledge developed in the genetics of fruit crops should improve the efficiency of fruit breeding programs and increase the probability of obtaining new fruit varieties with desired features.

Publications

• Fennell, A., K. Mathison, and J. Luby. 2006. Genetic segregation for indicators of photoperiod control of dormancy induction in Vitis species. Acta Hortic. 689:533-539. Luby, J. and A. Fennell. 2005. Fruit breeding for the Northern Great Plains at the University of Minnesota and South Dakota State University. HortScience 41:25-26. Luby, J.J. and D.S. Bedford. 2006. Apples. In: (J.R. Clark and C.E. Finn, eds.) Register of New Fruit and Nut Cultivars. HortScience 41:1101-1103.

Progress 01/01/05 to 12/31/05

Outputs
Crosses were made in apple and grape and selections were made in apple, grape, pear, and blackcurrant. An application was made for a US Plant Patent for MNUS 138 strawberry and this variety was made available for strawberry growers. MNUS 138 strawberry is an early to early midseason junebearing (short-day) type. The fruit is medium-large with a bright red color and a conic-wedge to blunt wedge shape. The flesh is orange-red and smooth and moderately firm in texture. The flavor is moderately intense with a tangerine-like flavor. The berry skin has been tough relative to other early season cultivars for the North Central US making it a durable berry. The original plant of MNUS 138 was screened for resistance to 5 common eastern US races of the pathogen causing red stele. The foliage has been highly resistant to powdery mildew and leaf scorch and moderately resistant to leaf spot. MNUS 138 strawberry should be a useful winter hardy, early season variety in the Midwestern and Northeastern US from USDA hardiness zone 3b to 5 Based on testing in Minnesota, Iowa, Michigan and Pennsylvania. MNUS 138 is being sold under the trademark Itasca strawberry. An application was made for a US Plant Patent on Frontenac gris grape and this variety was made available for grape growers. Frontenac gris is a grape (Vitis sp.) cultivar with gray (gris in French) colored fruit suitable for white wine production that is well adapted to the midwest U.S. It has excellent cold hardiness and disease resistance, together with very good productivity and wine quality. Frontenac gris was originally identified as a sport of Frontenac, a cultivar with black fruit that was introduced from the University of Minnesota grape breeding program. The juice of MN 1187 is relatively high in both sugar and acidity. Even under conditions of high disease pressure, this variety has been highly resistant to downy mildew. It has also exhibited moderate resistance to powdery mildew and black rot but is susceptible to foliar phylloxera infestation. Wines from Frontenac gris tend to have good body and pleasant aromas with very little of the herbaceous quality typical of many interspecific grape hybrids. The most common aroma component identified by tasters has been peach, with lesser amounts of tropical fruit aromas also noted. It will likely be suited to making table wines with some residual sugar as well as dessert wines. Provisional U.S. Plant Patent applications were made for a grape for red wine production and two varieties of apples. Frequency of day-neutral flowering in progeny of a strawberry cross, Tribute x Honey was assessed in collaboration with researchers at Michigan State University. Approximately 50% of the progeny exhibited strong and consistent day-neutral flowering even under relative hot summer conditions. A study of diversity among representatives of octoploid wild strawberries based on simple sequence repeat DNA markers suggests that the subspecies platypetala of species Fragaria virginiana is more closely affiliated with the species Fragaria chiloensis.

Impacts
New varieties of strawberries, apples, blueberries, grapes, and other fruits developed under this project will benefit fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers will benefit from their superior eating qualities and improved health-related traits. Knowledge developed in the genetics of fruit crops should improve the efficiency of fruit breeding programs and increase the probability of obtaining new fruit varieties with desired features.

Publications

• Mann, H., D. Bedford, J. Luby, Z. Vickers, and C. Tong. 2005.Textural and microscopic analysis of softening related changes in apple fruit during storage. HortScience 40:1815-1820.
• Cabe, P.R, A. Baumgarten, K. Onan, J.J. Luby, and D.S. Bedford. 2005. Using microsatellite analysis to verify breeding records: a study of Honeycrisp and other cold-hardy apple cultivars. HortScience 40:15-17.
• J.F. Hancock, S. Serce, C.M. Portman, P.A. Callow, and J.J. Luby. 2004. Taxonomic variation among North and South American subspecies of Fragaria virginiana Miller and F. chiloensis (L.) Miller. Can. J. Bot. 82:1632-1644.
• Luby, J.J., D.S. Bedford, P.L. Forsline. 2004. Winter hardiness in the U.S. Department of Agriculture Malus core collection. Acta Hort. 663:605-608.

Progress 01/01/04 to 12/31/04

Outputs
Crosses were made in apple and grape and selections were made in apple, grape, pear, and strawberry. A United States plant patent was issued for La Crescent grape. La Crescent is a grape used for white wine production that is winter hardy in USDA hardiness zone 4 and also has excellent wine making ability. The wine is usually best made with some residual sweetness and has flavors of citrus and tropical fruits. Provisional US plant patent applications were filed for another white wine grape and an early season Junebearing strawberry selection. The frequency of progeny with outstanding texture in crosses involving Honeycrisp, a cultivar with excellent texture were determined in crosses of Honeycrisp with 58 other parents. Approximately 25% of the crosses had at least one offspring with excellent texture and the proportion of offsping with excellent texture ranged from 0 to 20 % depending on the other parent used but was generally less than 10%. Cell size and the amount of work (force x distance) needed to break a segment of apple flesh were found to be correlated with good texture in Honeycrisp and some of its progeny. Response to shortening daylength appears to be the mechanism by which northern wild grapes (Vitis riparia) are stimulated to become dormant and begin acclimation for cold temperatures. The genetic control of this trait was demonstrated in crosses and backcrosses of a Vitis riparia clone with Seyval, a grape variety that does not respond to daylength changes.

Impacts
New varieties of strawberries, apples, blueberries, grapes, and other fruits developed under this project will benefit fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers will benefit from their superior eating qualities and improved health-related traits.

Publications

• Luby, J.J., D.K. Wildung, and G.J. Galletta. 2003. MNUS 248 (MesabiTM) strawberry. HortScience 38:481-483.
• Hemstad, P.R. and J.J. Luby. 2003. La Crescent, a new cold hardy, high quality white wine variety. Acta Hort. 603:719-722.
• Stushnoff, C., McSay, A.E., Luby, J. and Forsline, P.L. 2003. Diversity of phenolics antioxidant content and radical scavenging capacity in the USDA apple germplasm core collection. Acta Hort. 623:305-312.
• Luby, J.J. and P.R. Hemstad. 2004. Grape plant named 'La Crescent'. US Plant Patent 14,617.

Progress 01/01/03 to 12/31/03

Outputs
Crosses and/or new selections were made in grape, strawberry, apricot, blackcurrant, and apple. Thirty-eight strawberry cultivars and selections were compared in yield trials at 3 locations in Minnesota following a winterwith cold temperatures and little snow cover. Cavendish,Mesabi, and Sable were the hardiest cultivars, while the selections MNUS 692 and MNUS 796 were also notable performers. Virtually all blueberry flower buds were killed by late winter temperature fluctuations. Soft scald storage disorder on Honeycrisp apple has been averted in several experiments by storage for 3-5 days after harvest at 50F before refrigeration. An as yet unidentified orchard factor(s) also seem to be related to incidence of this disorder. An examination of nearly 200 apple cultivars and collections in the USDA Malus Core Collection showed conseiderable variation for winter injury over a 10 year period. Among the hardiest entries were accessions M. asiatica, M. baccata, M. brevipes, M. floribunda, M. ioensis, M. orientalis, and M. sieversii. Among the hardiest M. xdomestica entries were cultivars from Canada, Russia and the northern US including the cultivars Antonovka Kamenichka, Cortland, Haralson, Keepsake, McIntosh, Novole, Petrel, Viking, Yellow Transparent. Fire blight incidence was evaluated for a second seasonin a large apple germplasm collection including Malus sieversii, the ancestor of the domesticated apple. Varieties that transmitted extreme susceptibility or resistance were identified.

Impacts
New varieties of strawberries, apples, blueberries, grapes, and other fruits developed under this project will benefit fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers will benefit from their superior eating qualities and improved health-related traits.

Publications

• C.B.S. Tong, D.S. Bedford, J.J. Luby, F.M. Propsom, R.M.Beaudry, J.P. Mattheis, C.B. Watkins, and S.A. Weis. 2003. Location and temperature effects on soft scald in `Honeycrisp' Apples. HortScience 38:1-3..
• P.L. Forsline, H.S. Aldwinckle, E.E. Dickson, J. J. Luby, and S.C. Hokanson. 2003. Collection, maintenance, characterization and utilization of wild apples of Central Asia. Horticultural Reviews 29:1-62.

Progress 01/01/02 to 12/31/02

Outputs
Crosses and new selections were made in grape, blueberry, strawberry, blackberry, and apple. Forty strawberry cultivars and selections were compared in yield trials at 3 locations in Minnesota. Mesabi, Sable, MNUS 694, MNUS 674, and MNUS 138 were outstanding among newer varieties and breeding lines for yield, fruit size, and quality. Chippewa blueberry produced high yields in blueberry variety trials at 2 locations. Honeycrisp apple, released from this breeding program in 1991 continues to be planted widely throughout the U.S. Soft scald, a storage disorder sometimes observed in Honeycrisp fruit may be related to storage temperature and preharvest orchard conditions. An examination of over 300 apple varieties and selections showed a large range of variation for antioxidant activity, a health-promoting property related to the ability of phenolic compounds in the fruit to neutralize potentially damaging free-radical compounds in the body. Most of the selections with extremely high activity were not high in eating quality. Most commercial apple varieties had low to moderate antioxidant activity. Wild strawberry selections from Alaska and Alberta showed good potential as parents for dayneutral (everbearing) strawberries. Two selections from Ontario were the best parents for fruit size and fertility in crosses with domesticated strawberries. Fire blight was evaluated in a large apple germplasm collection including Malus sieversii, the ancestor of the domesticated apple. Varieties that transmitted extreme susceptibility or resistance were identified.

Impacts
New varieties of strawberries, apples, blueberries, grapes, and other fruits developed under this project will benefit fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers will benefit from their superior eating qualities and improved health-related traits.

Publications

• El-Shiekh, A.F., C.B.S. Tong, J.J. Luby, E.E. Hoover, and D.S. Bedford. 2002. Storage potential of cold-hardy apple cultivars. J. Am. Pom. Soc. 56:34-45.
• Connor, A.M., J.J.Luby, C.B.S. Tong, C.E. Finn, J.F. Hancock. 2002. Genotypic and environmental variation I antioxidant activity among blueberry cultivars. Acta Hort. 574: 209-213.
• Dale, A., J.J. Luby, and J.F. Hancock. 2002. Breeding dayneutral strawberries for northern North America. Acta Hort. 567:133-136.
• Hancock, J.F., J.J. Luby, A. Dale, P.A. Callow, S. Serce, and A. El-Shiekh. 2002. Utilizing wild Fragaria virginiana in strawberry cultivar development: Inheritance of photoperiod sensitivity, fruit size, gender, female fertility and disease resistance. Euphytica 126: 177-184.
• Luby, J.J., P.A. Alspach, V.G.M. Bus, and N. Oraguzie. 2002. Field resistance to fire blight in a diverse apple (Malus sp.) germplasm collection. J. Am. Soc. Hort. Sci. 127:245-253.
• Connor, A.M., J.J. Luby, and C.B.S. Tong. 2002. Variability in antioxidant activity in blueberry and the correlations among different antioxidant activity assays. J. Amer. Soc. Hort. Sci. 127:238-244.
• Connor, A.M., Luby, J.J. Hancock, J.F, Berkheimer, S. and Hanson, E. 2002. Changes in fruit antioxidant activity among blueberry cultivars during cold-temperature storage. J Agric. Food Chem. 50:893-898.
• Connor, A.M., J.J. Luby, C.B.S. Tong. 2002.Variation and heritability estimates for antioxidant activity, total phenolic content, and anthocyanin content in blueberry progenies. J. Amer. Soc. Hort. Sci. 127:82-88.
• Connor, A.M., J.J. Luby, C.B.S. Tong, C.E. Finn, and J.F. Hancock. 2002. Genotypic and environmental variation in antioxidant activity, total phenolic content, and anthocyanin content among blueberry cultivars. J. Amer. Soc. Hort. Sci. 127:89-97.

Progress 01/01/01 to 12/31/01

Outputs
Crosses and new selections were made in grape, blueberry, strawberry, blackberry, and apple. Forty strawberry cultivars and selections were compared in yield trials at 3 locations in Minnesota. Mesabi, Sable, Brunswick, MNUS 694 and MNUS 138 were outstanding among newer varieties and breeding lines for yield, fruit size, and quality. MN 1166, a cold hardy grape seletion for white wine production, was approved for introduction and is being propagated for release to nurseries. An examination of over 220 blueberry selections showed a large range of variation for antioxidant activity, a health-promoting property of blueberries related to the ability of phenolic compounds in the fruit to neutralize potentially damaging free-radical compounds in the body. Antioxidant activity was strongly correlated with total phenolic content, anthocyanin content, and, to a lesser degree with fruit size or skin surface area. Approximately half of the observed variation was estimated to be due to genetic rather than environmental effects suggesting that antioxidant levels in blueberry can be improved through breeding. Indirect selection by measuring phenolic or anthocyanin levels may be more efficient as these traits are less expensive to measure than antioxidant activity. Using molecular markers to assist selection in a fruit breeding program may be justified based on internal cost savings for long-lived fruit plants such as a apple or grape but not in a shorter-lived plant such as strawberry. Marker assisted selection may be justifiable for traits controlled by one or two genes but are not likely to be cost effective, or genetically effective, for traits controlled by many genes.

Impacts
New varieties of strawberries, apples, blueberries, grapes, and other fruits developed under this project will benefit fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers will benefit from their superior eating qualities and improved health-related traits.

Publications

• Luby, J.J. and D.V. Shaw. 2001. Does marker-assisted selection make dollars and sense in a fruit breeding program? HortScience 36:872-879.
• Hancock, J.F., C. E. Finn, S.C. Hokanson, J.J. Luby, B.L. Goulart, K. Demchak, P.W. Callow, S. Serce, A.M. C. Schilder, and K.E. Hummer. 2001. A multistate comparison of native octoploid strawberries from North and South America. J. Amer. Soc. Hort. Sci. 126:579-586.
• Luby, J.J., P.L. Forsline, H. Aldwinckle, V. Bus, and M. Geibel. 2001.Silk Road Apples - Collection, Evaluation, and Utilization of Malus sieversii from Central Asia. HortScience 36:225-231.
• Luby, J.J., D.K. Wildung, G.J. Galletta. 2001. MNUS 210 (WinonaT) strawberry. Hortscience 36:392-394.
• Hancock, J.F., P. Callow, A. Dale, J. Luby, C. Finn, S. Hokanson, and K. E. Hummer. 2001. From the Andes to the Rockies: Native strawberry collection and utilization. HortScience. 36:221-225.
• Olfelt, J., G. Furnier, and J. Luby. 2001. What data determine whether a plant taxon is distinct enough to merit legal protection? A case study of Sedum integrifolium (Crassulaceae). Am. J. Bot. 88:401-410.
• Bus, V., P. Alspach, J. Luby, S. Bradley, M. Hofstee, and L. Brewer. 2000. Increasing genetic diversity in apple breeding to improve the durability of pest and disease resistance. Acta Hort. 538:185-190

Progress 01/01/00 to 12/31/00

Outputs
Crosses and new selections were made in grape, blueberry, strawberry, blackcurrant, and apple. Forty strawberry cultivars and selections were compared in yield trials at 3 locations in Minnesota. Mesabi, Brunswick, MNUS 691, MNUS 694 and MNUS 138 were outstanding among newer varieties and breeding lines for yield, fruit size, and quality. MN 5451, a late ripening, cold hardy blueberry selection, was approved for introduction and is being propagated for release to nurseries. In a trial of 16 blueberry cultivars from 3 locations (Becker, MN; Corvallis, OR; South Haven, MI) Bluegold and Northland had the highest antioxidant activity when assayed over 2 years. Effects of locations, years within locations, and interactions of cultivars with locations and years were also significant. Antioxidant activity was strongly correlated with total phenolic content, anthocyanin content, and fruit size or skin surface area. A study of phylogenetic relationships among strawberry species based on chloroplast DNA sequences showed little variation. Octoploid progenitors of the domesticated strawberry were most closely related to other polyploid species (Fragaria moschata, Fragaria orientalis) and the diploid species Fragaria vesca.

Impacts
New varieties of strawberries, apples, blueberries, grapes, and other fruits developed under this project will benefit fruit growers in Minnesota and the northern USA due to their cold hardiness, disease, and pest resistance. Fruit consumers will benefit from their superior eating qualities and improved health-related traits.

Publications

• Hemstad, P.R. and J.J. Luby. 2000. Utilization of Vitis riparia for the development of new wine varieties with resistance to disease and extreme cold. Acta Hort 528:487-490..
• Potter, D., J. Luby, and R. Harrison. 2000. Phylogenetic relationships among species of Fragaria L. (Rosaceae) inferred from non-coding nuclear and chloroplast DNA sequences. Syst. Bot. 25:337-348.
• Harrison, R.E., J.J. Luby, G.R. Furnier, J.F. Hancock. 2000. Differences in the apportionment of molecular and morphological variation in North American Strawberry and the consequences for genetic resource management. Genet. Res. and Crop Evol. 47:647-657.

Progress 01/01/99 to 12/31/99

Outputs
Crosses and new selections were made in grape, blueberry, strawberry, apricot, and apple. MNUS 248 strawberry selection, marketed as Mesabi, was available to growers as a cold hardy, high yielding midseason variety with creamy texture. It should be useful for growers in cold climates for pick-your-own or on-farm sales. Forty strawberry cultivars and selections were compared in yield trials at 3 locations in Minnesota. Mesabi, Winona, Sable, MNUS 551, and MNUS138 were outstanding among newer varieties and breeding lines for yield, fruit size and quality despite thrips damage at Excelsior, root rot at Morris, and excessive rain at Grand Rapids. In assessments of antioxidant capacity, presumably related to several human health benefits, the blueberry variety Bluegold was higher than 50 other varieties and selections tested and also transmitted this character to its offspring. Six grape selections were identified as potential rootstock varieties based on their growth habit, rooting ability, and phylloxera resistance. They are being grafted to examine their effects on growth, cold hardiness, and fruiting of scion varieties.

Impacts
New varieties of strawberries, apples, blueberries, grapes and other fruits developed under this project will benefit fruit growers in Minnesota and the northern USA due to their cold hardiness, disease and pest resistance. Fruit consumers will benefit from their superior eating qualities and improved health-related traits.

Publications

• Tong, C., D. Krueger, Z. Vickers, D. Bedford, J. Luby, A. El-Shiekh, K. Shackel, & H. Ahmadi. 1999. Comparison of softening-related changes during storage of the 'Honeycrisp' apple, its parents, and 'Delicious'. J. Amer. Soc. Hort. Sci. 124:407-415.
• Harrison, R.E., J.J. Luby, G.R. Furnier, J.F. Hancock, D. Cooley. 1998. Variation for susceptibility to crown rot and powdery mildew in wild strawberry from North America. Acta Hortic. 484:43-48.
• Hokanson, S., P. Forsline, J. McFerson, W. Lamboy, H. Aldwinckle, J. Luby, A. Djangaliev. 1998 Ex situ and in situ conservation strategies for wild Malus in Kazakhstan. Acta Hortic. 484:85-92.
• Luby, J.J., E.E. Hoover, M. Peterson, D.J. Larson, and D.S. Bedford. 1998.Cold hardiness in the USDA Malus core germplasm collection. Acta Hortic. 484:109-114.

Progress 01/01/98 to 12/31/98

Outputs
Crosses and new selections were made in grape, blueberry, strawberry and apple. Plants of MNUS 248 strawberry was increased in nurseries for planned distribution in 1999. Trees of MN 1824 apple, a high quality, early season cultivar were available from nurseries under the trademark name, Zesta!. Forty strawberry cultivars and selections were compared in yield trials at 3 locations in Minnesota. Yield levels were low at Morris due to root rot and at Excelsior due to poor stand establishment. MNUS 248 was very promising for yield, quality, and fruit size. Collections of F. virginiana and F. chiloensis were evaluated for variation in morphology and RAPD band patterns. Approximately 50 selections from the grape breeding program were evaluated for graft compatibility as part of their evaluation for potential as rootstocks.

Impacts
(N/A)

Publications

• HANCOCK, J.F., B.L. GOULART, J.J. LUBY, AND M.P. PRITTS. 1997. The strawberry matted row: practical cropping system or dated anachronism? Adv. Strawberry Research 16:1-4.

Progress 01/01/97 to 12/31/97

Outputs
Crosses and new selections were made in grape, blueberry, strawberry and apple. Foundation stock of MNUS 248 strawberry were distributed to nurseries for propagation. Forty strawberry cultivars and selections were compared in yield trials at 3 locations in Minnesota. Yield levels were low due to late fall and early spring low temperatures. MNUS 248, Mira, and Cavendish were very promising for yield, quality, and fruit size. A collection of wild strawberries (Fragaria virginiana ssp. glauca) was made in the southern Rocky Mountains for future germplasm evaluation. Crosses of 10 Fragaria chiloensis with 14 F. virginiana were evaluated in strawberry and 63 selections were made further testing for germplasm improvement. Approximately 50 selections from the grape breeding program were evaluated for rooting, phylloxera susceptibility, and vigor as part of their evaluation for potential as rootstocks.

Impacts
(N/A)

Publications

• Harrison, R.E., J.J. Luby, G.R. Furnier and J.F. Hancock. 1997. Morphological and molecular variation among populations of octoploid Fragaria virginiana and F. chiloensis (Rosaceae) from North America.
• Hokanson, S.C., J.R. McFerson, P.L. Forsline, W.F. Lamboy, J.J. Luby, A.D. Djangaliev, and H.S. Aldwinckle. 1997. Collecting and managing wild Malus germplasm in its center of diversity. HortScience
• Sakin, M., J.F. Hancock, and J.J. Luby. 1997. Identifying new sources of genes that determine cyclic flowering Rocky Mountain populations of Fragaria virginiana ssp. glauca Staudt. J. Amer. Soc. Hort. Sci.
• Harrison, R.E., J.J. Luby, G.R. Furnier. 1997. Chloroplast DNA restriction fragment variation among strawberry taxa (Fragaria spp.). J. Amer. Soc. Hort. Sci. 122:63-68 .
• Galletta, G.J., J.L. Maas, C.E. Finn, B.J. Smith, C.L. Gupton, J.J. Luby, and D.K. Wildung. 1997. New strawberries from the USDA cooperative breeding programs. Acta Hortic.439:227-232.
• Luby, J. 1997. Elegant nose and powerful body - who were the parents of such nobility? Nature Genetics 16:4-5

Progress 01/01/96 to 12/30/96

Outputs
New introductions were: Frontenac, a cold-hardy, disease-resistant, red wine grape; Polaris, an early-season blueberry with firm, crisp, aromatic fruit; Chippewa, a highly productive, midseason blueberry; and Winona, a productive, late-season strawberry with large fruit, resistance to red stele root rot and leaf diseases. In yield trials at 3 locations in MN, MNUS 248, Winona, Mira and Cavendish were promising for yield, quality, and fruit size. The USDA Malus Core Germplasm Collection was evaluated for winter injury following the severe winter of 1995-96. Among the hardiest species were baccata, halliana, kansuensis toringoides, micromalus, prattii, and prunifolia. The hardiest domesticated apples were cultivars from Canada, Russia, and the northern US including Macfree, Haralson, Brightgold, Petrel, Keepsake, Empire, Yellow Transparent, Novosibirski Sweet, and Antonovka. Over 300 wild strawberries were observed for susceptibility to Phytophthora crown rot and powdery mildew. Accessions from the Rocky Mts and eastern Cascade Mts were most susceptible to powdery mildew. Plants from the western Cascades and Olympic Mts were most susceptible to crown rot. Ploidy levels of 61 Actinidia ("hardy kiwifruit") accessions from 8 species and 3 interspecific hybrids were determined by flow cytometry. A. kolomikta and polygama were diploid; arguta, callosa, melanandra, and purpurea were tetraploid; deliciosa and chinensis were hexaploid. One hybrid was hexaploid and two were tetraploid.

Impacts
(N/A)

Publications

• El-Shiekh, A., D.K. Wildung, J.J. Luby, K.L. Sargent, and P.E. Read.1996 Long-term effects of propagation by tissue culture or softwood single-node cuttings on growth habit, yield and berry weight of 'Northblue' blueberry. J. Amer. Soc.

Progress 01/01/95 to 12/30/95

Outputs
Crosses and new selections were made in grape, strawberry and apple. The name ofFrontenac has been chosen for MN 1047 grape. Frontenac is a cold-hardy, disease-resistant, red wine grape. It is available in 1996. MN 408 blueberry will be named Polaris and is available in limited quantities in 1996. It is an early-season cultivar with aromatic flavor and firm, crisp texture. MNUS 210 strawberry will be named Winona and will be introduced in 1996. It is a productive, late-season cultivar with very large fruit, resistance to red stele root rot and leaf diseases. Thirty cultivars and selections were compared in yield trials at locations in Minnesota. MNUS 248, MNUS 210, Jewel and Cavendish were very promising in the midseason to late season for yield, quality, and fruit size. Annapolis continued to perform well in the early season. Minnesota apple cultivars were examined for their storage ability in ambient and controlled atmospheres. Controlled atmosphere storage lengthened the storage life of Honeygold, Haralson, and Regent. Honeycrisp performed equally in both atmospheres up to 9 mo after harvest. A ten year study comparing Northblue blueberry plants propagated by tissue culture with plants propagated by stem cuttings showed no diffences between the two treatments for yield, plant size or berry weight at Becker in central Minnesota. At Grand Rapids, in northern Minnesota, the micropropagated plants were larger and yielded more even 10 years after planting.

Impacts
(N/A)

Publications

Progress 01/01/94 to 12/30/94

Outputs
Crosses and new selections were made in grape, blueberry, strawberry and apple. MN 1047 grape, MN 1824 apple, MN 408, and MN 393 blueberries are being increased for release. A recurrent selection scheme to improve fruit size in wild strawberry accomplished only marginal increases in fruit size but large increases in fruit number and female fertility. Thirty strawberry cultivars and selections were compared in yield trials at 4 locations in Minnesota. MNUS 248, MNUS 210, Jewel, and Cavendish were very promising in the mid to late season for yield quality and fruit size. The phylogeny of 13 strawberry taxa was constructed based on endonuclease restriction sites in the chlorplast DNA. European and American Fragaria vesca could be distinguished. Octoploid strawberries in the northern US form 5 distinct groups based on morphology but only 2 or 3 groups based on selectively neutral DNA markers (random amplified polymorhic DNA). Long-storing apple cultivars, Honeygold and Delicious were compared with short-storing cultivars Cortland, Macoun, and Honeygold to relate chemical and physical components of the flesh to cell ultrastructure. Long-storing apples had flesh with larger cells and breakage was through cells rather than along cell walls when force was applied suggesting greater integrity of the middle lamella. Several wild western US blueberry species were screened in vitro for adaptation to higher pH tolerance. Vaccinium ovalifolium was most tolerant followed by V. membranaceum.

Impacts
(N/A)

Publications

Progress 01/01/93 to 12/30/93

Outputs
Crosses and new selections were made in blueberry, strawberry, and apple. MN 1047 grape, MN 1824 apple, MN 408 and MN 393 blueberries are being increased for release. Five primocane-fruiting raspberry cultivars were observed for growth, flowering, and fruiting parameters in order to study genotype x environment interactions. The second cycle of a recurrent selection scheme to improve fruit size in wild strawberry was completed. Selected individuals were intermated to form the C2 population. Twenty cultivars and selections were compared in yield trials at 4 locations in Minnesota. MNUS 248, MNUS 210, and MNUS 57 were very promising in the midseason to late season for yield, quality, and fruit size. MNUS 225 was promising in the early-midseason. Eight cold hardy grape cultivars and selections were compared in consumer sensory evaluations for their quality as table grapes or for producing juice or jelly. Consumers could be distinctly categorized based on a principal components analysis of their patterns of preference for the various cultivars. While the largest category preferred standard products with which they were presumably familiar, about one third constituted a group that preferred products made from the hardy cultivars. The phylogeny of 13 strawberry taxa was constructed based on endonuclease restriction sites in the chlorplast DNA. All octoploid strawberry species were grouped in a single taxon with no close similarity to taxa at other ploidy levels.

Impacts
(N/A)

Publications

Progress 01/01/92 to 12/30/92

Outputs
Crosses were made in blueberry, strawberry, and apple. New selections were made in these crops and also in raspberry. Five primocane-fruiting raspberry cultivars were observed for growth, flowering, and fruiting parameters in order to study genotype x environment interactions. The first cycle of a recurrent selection scheme to improve fruit size in wild strawberry was completed. Mean fruit weight of the Cycle 0 population was 0.74 g per fruit, and mean fruit weight of selected individuals (top 20% of population) was 0.81. Selected individuals were intermated to form the C1 population. Wild strawberries (Fragaria virginiana) from 37 sites in the northern Rocky Mountains were characterized for 10 leaf traits to discern whether any patterns of morphological variation existed in relation to environmental or geographical factors. Four principal components (PC) explained 88% of the total variance among collections. The first PC was a multivariate measure of leaf size accounting for 55% of the total variance. Two groups of collections could be distinguished by relating PC1 to geographical or environmental factors. The first group, from the Black Hills, had high values of PC1 indicating large leaf size which suggested influence of the eastern spp. virginiana. Collections from further west in Montana, Wyoming, and Idaho were more typical of the smaller-leaved spp. glauca. In this group, collections from high elevations (>2000 m) had smaller multivariate leaf size.

Impacts
(N/A)

Publications

Progress 01/01/91 to 12/30/91

Outputs
Crosses were made in blueberry, strawberry and apple. New selections were made in these crops and also raspberry. Ten strawberry selections were established in replicated trials. Promising selections in advanced trials included MN 1824, an early season apple; MN 393 and MN 408, high quality, hardy blueberries; MNUS 52, 57 and 118, late-season, red stele-resistant strawberries with high quality. Variation in the MN wild strawberry Fragaria virginiana was related to geographic floristic provinces and may involve introgession from the cultivated strawberry. Genders in the wild strawberry include very fertile females and hermaphrodites with varying fertility. In half-high blueberries, fruit and seed set were negatively associated with increased proportions of self pollen in mixtures with outcross pollen, indicating that post-fertilization abortion affected seed formation. Multiple self-pollinations gave higher fruit set than single self-pollinations but less than outcross-pollinations at various times after selfing. Self-fertility is apparently not simply inherited and progenies exhibited a large range of responses regardless of parental levels.

Impacts
(N/A)

Publications

Progress 01/01/89 to 12/30/89

Outputs
Some Vaccinium angustifolium genotypes produced progeny that survived and grew vigorously when seeds were germinated in vitro at pH 6.0 on a modified Zimmerman's medium. Blueberry progenies from V. angustifolium and V. corymbosum varied greatly in growth traits the field at pH levels 4.5, 5.5, and 6.5. Specific parents for high pH tolerance were identified. Nutrient concentrations were analyzed in plants grown at pH 4.5 and 6.5. Population x pH regime interactions were detected for K, Ca, Fe, Mn, Zn, and B concentration and for K and Mn uptake. Differences in uptake and concentration were correlated with the proportion of V. angustifolium ancestry but could not be associated with better plant growth at high pH. Blueberry plants propagated by tissue culture or leaf buds did not differ in yield or berry weight after 5 years in the field. Wild strawberry (Fragaria virginiana) clones had more aromatic compounds than cultivars and often in greater amounts as detected by gas chromatography. Wild clones and their progeny in crosses with cultivars segregated for presence and amount of these compounds.

Impacts
(N/A)

Publications

Progress 01/01/88 to 12/30/88

Outputs
Nordic, a summer-fruiting red raspberry, was introduced in 1988. Three starwberry selections, MNUS 52, 57 and 99 continued to perform well in statewide yield trials and are being propagated for possible release. MN 1711 apple will be named Honeycrisp and released in 1991 or 1992. Wild strawberry (Fragaria virginia) genotypes showed considerable variation for fruit color, shape and size. Many exhibited a day-neutral flowering response for a second year in the greenhouse environment, though expression of this trait was not as great in the field. Wild strawberries produced many more crowns & runners than check cultivars. Pollination studies in blueberry indicated considerable segregation for self-fruitfulness. A pruning study initiated with 10 year old half-high plants showed no effect of pruning in the first year on yield or berry weight. Yield was slightly reduced in the second year. Freezing tests of raspberry flower buds indicated variation for lethal temperature in March 1988 but not in November 1987 or January 1988.

Impacts
(N/A)

Publications

Progress 01/01/87 to 12/30/87

Outputs
New cultivars introduced in 1987 were Redwing, a fall-fruiting raspberry, and Summercrisp, a hardy, crisp-fleshed, early-season pear. Three strawberry selections from the MN-USDA breeding program are being virus-indexed for cooperator testing and eventual release. Six additional selections were established in statewide trials. Large proportions of day-neutral genotypes were found among 40 Minnesota populations of wild strawberry. Hermaphrodite was the predominant sex type and few males were noted. Path analysis of yield components in primocane-fruiting raspberries indicated that yield was most strongly determined by canes per m row. Widespread adaptation may be determined by having few negative relationships. Pollination studies in half-high blueberry indicated that the cultivar Northblue was completely self fruitful while Northcountry and Northsky were only partially self fruitful. Several genotypes were completely self fruitful. There were considerable differences among blueberry genotypes for axillary and adventitious shoot development which were not substantially affected by stage of development or light quality treatments. Several families of lowbush blueberry appeared to be fairly tolerant of higher pH levels.

Impacts
(N/A)

Publications

Progress 01/01/86 to 12/30/86

Outputs
New cultivars introduced in 1986 were Alderman plum and Northcountry blueberry. Redwing, a primocane-fruiting raspberry, and Summercrisp, a crisp, early-season pear, will be introduced in 1987. Five selections from MN-USDA strawberry breeding program were established in statewide4 cultivar trials. An 11 parent diallel mating design with lowbush blueberry indicated most were self-incompatible. Some parents had similar crossability patterns with others. A study of the inheritance of fruit quality traits in blueberry indicated that general combining ability was more important than specific combining ability for color, firmness and picking scar. GCA effects were not highly correlated with parental phenotype. Unusual segregations for fruit color with an excess of dark-colored genotypes were observed when lowbush blueberries were crossed with half-high or highbush. Wild strawberries (Fragaria virginiana) collected from 40 sites in Minnesota exhibited considerable variability for repeat flowering and sex expression development of primocane-fruiting raspberries is very closely related to heat units above 0C. Reproductive development is apparently delayed in seasons where heat units are accumulated very quickly. In vitro pollen growth has been observed using 0.1% celluflor as a vital stain for raspberry, strawberry, blueberry and apple pollen.

Impacts
(N/A)

Publications

Progress 01/01/85 to 12/30/85

Outputs
Two cultivars will be introduced in 1986: Alderman (MN416) plum and Northcountry (MN350) blueberry. Differences were found among strawberry cultivars for rate of flower bud development and concentrations of starch and sugars in the crown. No relationship between these traits and cold hardiness as measured by controlled freezing tests was observed. The inheritance of several traits was studied in blueberries in 1983-85. Heritability estimates were moderately high (0.44 to 0.78) for bloom date, ripe date, fruit filling period, fruit weight, plant height and plant stature and low (0.13 to 0.27) for plant diameter. General combining ability was more important than specific combining ability for all traits except plant diameter. Variation in foliar nutrient composition was observed in blueberry progenies with varying proportions of lowbush ancestry. Higher levels of total N, P, Ca, Cu and, especially, Mn were associated with higher levels of lowbush ancestry. Mn levels have been associated with ability of plants to tolerate higher soil pH levels. Lowbush blueberry clones exhibiting different levels of fall fruiting in the field also showed different flowering patterns in response to photoperiod in controlled studies. This suggests that fall fruiting in the field may occur partly in response to different photoperiod and that it may be possible to select genotypes with a high level of fall fruiting under controlled conditions.

Impacts
(N/A)

Publications

Progress 01/01/83 to 12/30/83

Outputs
General combining ability (GCA) effects of blueberry parents were variable from year to year and heritability was low for fall growth cessation and winter injury (WI). Lowbush parents imparted positive effects for WI resistance in years with snow cover but negative effects in years without snow cover. GCA variance was more important than specific combining ability variance for WI. Lowbush parents had high GCA effects for off-season flowering (OFS) and heritability was high. OFS consistently occurred in certain lowbush clones over 3 seasons and may potentially be exploited to avoid WI and provide a fall crop. Flower initiation was similar in OFS and normal clones but by late summer, buds in OFS clones had more developed florets. Fall fruit was larger and contained fewer seeds than summer harvested fruit. Vegetative growth of potted blueberry plants used for cuttings was stimulated by pruning, long daylength and high intensity light. Yield components varied among fall-fruiting rasberry genotypes. 'Heritage' which outyielded the other earlier-fruiting selections did so by producing more fruit/node. Differences among genotypes in height and total nodes were established early in the growing season. Flowering proceeded more rapidly down 'Heritage' canes but fruiting was delayed compared to other genotypes. Apple seedlings ranked similarly for cold hardiness for both juvenile and adult tissue suggesting that juvenile selection may be effective.

Impacts
(N/A)

Publications

Progress 01/01/82 to 12/30/82

Outputs
Flowering and vegetative responses of hybrid blueberry progenies to Alar and Promalin were studied. Promalin reduced number of buds/shoots, decreased leaf bud, shoot bud ratio and increased shoot length. Alar application resulted in fewer actively growing shoots in mid-September. Strawberry genotypes varied in tolerance to terbacil in greenhouse and field experiments. Delite was the least and Redcoat the most tolerant in tests of cultivars and their open-pollinated progenies. Visual ratings of phytotoxic response appear to be a reliable screening technique for future breeding efforts. High levels of nitrogen fertilizer applied to newly planted strawberries did not increase fruit yield. Late-summer applications increased fruit yield up to 2,000 lb./A. Terbacil herbicide applied to renovated strawberries controlled annual weeds without depressing fruit yields. Chloroxuron divided by napropamide tank mix gave excellent control in newly planted strawberries and raspberries. Fusilade alone and in tank mix with chloroxuron gave excellent control of grasses in new plantings. Batto, Sinbar and Nortron inhibited runner plant production in strawberries. Tank mixes of Volpar plus Sinbar and Sinbar plus Simazine gave effective weed control in blueberries. Raspberries in rows 5 or 6 feet apart and mowed after harvest continued to have yields equal to unmowed plants in rows 10 to 12 feet apart.

Impacts
(N/A)

Publications

Progress 01/01/81 to 12/30/81

Outputs
Emergin primocanes of red raspberry received applications of NAA at 6 and 12" heights. The top growth of the primocanes was killed, but reemerged after treatment. The higher conc. (1 and 2%) reduced height, density and fruit yield the year following treatment. Tolerance of 8 strawberry cvs. to herbicide terbacil was studied. Rates of .5 lb/A, greenhouse, and 1.75 lb/A, field, caused sufficient phytotoxicity to determine varying degrees of tolerance. Redcoat was most tolerant and Delite, least. Alar and promalin applied to established Trumpeter strawberries at full bloom reduced yield and increased size. The "physiological rest period" of seeds of 3 apple cvs. was studied. Haralson, cold hardiest, had the longest "rest period" and the least hardy, Red Delicious, the shortest. Velpar and terbacil herbicides effectively controlled annual weeds in half-high blueberries. Fruit yield was highest from plants receiving terbacil or a terbacil-Velpar combination. Alar prevented preharvest drop and increased firmness of McIntosh apples. Established red raspberries, received several pruning and thinning treatments. Fruit yields were highest from plants growing in rows spaced 5 and 6 ft. Yields from plants mowed after harvest, equaled non-mowed plants in rows spaced 10 and 12 ft. In newly planted strawberries, Devrinol was more effective against grass weeds than broadleaf. Terbacil, Velpar, and a mixture of each effectively controlled annual weeds in newly planted raspberries.

Impacts
(N/A)

Publications

Progress 01/01/80 to 12/30/80

Outputs
Low temperature exotherms have been observed in seeds of apple, raspberry, blackberry, blueberry, and cabbage. Low temperature exotherms occur in dormant flower buds and stem tissues of several species as a result of freezing of deeply supercooled water. Deep supercooling is thought to represent an important freezing avoidance mechanism. Attempts were made to correlate low temperature exotherms in seeds with known hardiness level of those species whose seeds exhibit low temperature exotherms. So far we have been unable to find a correlation. Size distribution patterns of strawberry cultivars tested show MN 2374 had consistently the highest fruit size over all picking dates. Yield data from HRC indicate Trumpeter as highest yielding strawberry cultivar this year. Indications of herbicide tolerance study on strawberry cultivars are variable with Trumpeter, Darrow, and Holiday showing most tolerance. Terbacil gave complete control of weeds at 1 lb/acre active when applied at renovation time. Fireblight-resistant progeny studies on apples indicate possible development of quality apples with resistance. Definite difference in growth patterns of irradiated Beacon apples with some trees being partially dwarf and having different ripening dates as opposed to original Beacon. MN 629 raspberry showed better early season yields than any of existing cultivars. When applied to McIntosh apples, Alar provided preharvest drop control and increase of fruit regulator firmness at harvest.

Impacts
(N/A)

Publications

Progress 01/01/79 to 12/30/79

Outputs
Freeze-fracture electron micrographs were used to study membrane changes in lettuce seeds at different stages of hydration and potato cell cultures from several species under cold stress. Consistent changes were found at specific hydration levels: in air dry seeds, membranes are amorphous and lipids are in spherical liposomes; at 20-25% seed H(2)0, the structure is crystalline and lipid bodies reorient into membrane bilayers. Membrane protein particles aggregated in frost resistant Solanum acaule up to 10 days after exposure to the acclimation temp., then redistributed. No aggregation was observed in susceptible S. tuberosum. The Haralson and Regent apples have wide picking dates as they effect storage quality. Others, Red Baron and Sweet Sixteen, have narrower requirements. Data for degree days (base 4.4 degrees C) for air and soil temp. plus sunshine hours were incorporated into a model to predict a harvest date (+ 1 day) for Redcoat strawberries. Black polyfoam mulch (.63 cm thick, .03 g/cm 3 density) insulated strawberries from winter cold as well as straw. Current costs may prohibit use. A 7 year old high density planting of 'State Fair' apple was hardy and averaged 2 times the average state yield. 'Regent' was completely killed in the same study. Terbacil plus napnopamide or DCPA controlled annual weeds in newly planted strawberries growing in sandy and clay-loam soils. Alone or in combination, terbacil and Velpar controlled both annual and perennial weeds in hybrid blueberries growing in sandy soils.

Impacts
(N/A)

Publications

Progress 01/01/78 to 12/30/78

Outputs
Fruit breeding highlights: 'Keepsake' apple available Spring 1979, new variety with outstanding storage capability; 'Regent' winter injured probably from sunscald and inability to harden early enough under warm and wet fall conditions; selected No. 1732 (18% sugar) and No. 1752 top quality green fruited apples; also, several dwarf, precocious, hardy rootstocks; V. riparia clones from Manitoba acclimated very early; No. 603 raspberry slated for introduction, top quality, aphid resistant, anthracnose tolerant, high yield, prickle free. Differential thermal analysis of native V. riparia grape revealed: buds avoid freezing by deep supercooling; low temp exotherms (LTE) associated with death at moment of freezing; capable of dehydrating to point where no LTE present and no injury less than minus 40 degrees C; canes exhibit several LTE associated with injury to xylem and phloem; LTE also present in refrozen material thus DTA is not useful for diagnosis; the degree of cold tolerance is directly related to moisture content which drops even when tissues are frozen. Membrane conformational changes revealed by freeze-etch electron micrographs are related to hydration levels and cold resistance of lettuce seed preparations. Terbacil (new registration) controlled grass and broadleaf weeds in strawberries on silty clay loam and sandy soils but also caused injury at high rates. Glyphosate was effective for quackgrass and Canada thistle control as a preplant treatment.

Impacts
(N/A)

Publications

Progress 01/01/77 to 12/30/77

Outputs
Cloudberry flower bud hardiness was determined by low temp exotherms. Several hundred seedlings and parental clones were monitored during acclimation and a quantitative analysis formula was developed to estimate genetic and environmental components of time-influenced cold hardening. Acclimation tests of 12 woody species growing 200 miles north of the Arctic circle with marine and mountain ecotypes showed that prevailing temp was a dominant factor in controlling cold acclimation and the range in hardiness was minus 20 degrees to minus 196 degrees C. Lettuce seed avoids freezing by supercooling at 20 to 45% H(2)O. Neither light quality nor duration of imbibition influenced survival level. The supercooling avoidance mechanism ceased to function if the endosperm envelope was damaged. Hydration level also appears to be a controlling factor associated with low temp exotherms and cold survival in hardy, wild grape flower buds. State Fair and Sweet 16 apples and Swenson Red and Edelweiss grapes have been named as new cultivars for release, spring 1978 (C. Stushnoff). On silty clay loam soil at the Hort Res Center, Basagram herbicide, effective against broadleaf weeds, failed to control grasses and injured strawberry plants. Mixtures of Dacthal, Tenoran or Diphenamid were very effective. Tenoran was ineffective against grasses. On loamy sand at Becker, Terbacil and Tenoran and mixtures of Dacthal, Tenoran, or Diphenamid gave excellent weed control.

Impacts
(N/A)

Publications

Progress 01/01/76 to 12/30/76

Outputs
Cold hardiness increases basipetally for blueberry flower buds within a twig andalso for florets within a bud. Differential thermal analysis (DTA) profiles of a dormant bud consist of a large rate independent free water exotherm (EX) not related to hardiness and several small rate dependent peaks which do represent death of each floret. Artificially dehydrated buds (14 days at 46% RH, -51.6 bars H(2)O pot., 4C) gained hardiness from -10C to -25C. Outdoor buds of a hardy hybrid lost all exotherms and hardened to -40C under conditions of low temp and low RH, whereas non-hardy cultivars did not. DTA of over 20 Prunus species revealed that those with low temp EX are not indigenous north of -40C isotherm whereas those w/o low temp EX are. Low temp EX were also found in stems & deacclimated buds of the hardy grape buds. Straw mulch protected strawberry plants & increased berry yield when snow cover not present. Clear poly promoted early plant growth in spring but plants injured by late spring frosts. Both terbacil and glyphosate controlled quackgrass in blueberries. Terbacil most affective weed control in McIntosh apples. Trees growing under a straw mulch had greatest growth & fruit yield. Early apple yield greatest with M.26 rootstock. Applications of ethrel & alar increased red color, fruit drop, firmness and decreased storage life of Beacon, McIntosh, Spartan, Connell Red, Haralson and Fireside apples.

Impacts
(N/A)

Publications

Progress 01/01/75 to 12/30/75

Outputs
Rapid wilt, seedling screening for resistance to fireblight in applies with 4-methyl-catechol-o-odiacetic acid is influenced by shoot development stage. N. Amer. apple cultivars were classified into hardiness groups. Mutation induced dwarf Beacon apples have a higher cortex to xylem ratio than standard trees. The original apple mutants remained dwarf but clonal propagules were variable. Several hundred blueberry stock plant selections were propagated from leaf-buds.Mature blueberry seedlings were transplanted as dormant fall and spring dug bareroot plants and as winter stored stock without mortality. Blueberry seedling adaptability trials at Grand Rapids, Staples and Duluth yielded 2 to 6 lbs/plant(4,000 to 12,000 lbs/acre). Collections of native, indigenous Vitis riparia in the Minnesota River valley possess 12 to 26% soluble solids (sugar); 2.5 to 4.5%titrateable acidity; and large variation in berry and cluster size. Three raspberry selections are resistant to aphid colonization based on laboratory andfield screening trials. Seasonal cold hardiness response of strawberries shows increased resistance with onset of short days and exposure to +27(o)F to +15(o)+f. Fall nutritional levels influence hardiness with high N imparting susceptibility and balanced N, P, K imparting resistance. Terbacil and glyphosate controlled quackgrass in blueberries and young applies. Simazine andparaquat controlled quackgrass in blueberries on sandy soil. Excessive winter straw mulch reduced fruit

Impacts
(N/A)

Publications

Progress 01/01/74 to 12/30/74

Outputs
Rapid screening for resistance to fireblight was accomplished by rating wilting response of succulent apple, pear, hawthorn and mountain ash shoots following placement in 50mM, 4-methyl-catechal-o, o-diacetic acid, in 24 hours. Midwinterloss of cold tolerance following warm temperatures was artifically reproduced and found useful for lab screening apple and blueberry seedlings. Breeding behavior of cold resistant blueberry flower buds shows continuous variation. Specific parents exhibit high probability to produce seedlings which survive -40C. Propagation of blueberry hybrids was improved 100% + by rooting single bud leaves versus standard softwood cuttings. Two apple, 8 strawberry, 10 blueberry, and 7 grape advanced selections were evaluated as worthy of propagation for release to industry. Glyphosate herbicide controlled quackgrassin blueberries and in a fall preplant, application, in strawberries.

Impacts
(N/A)

Publications

Progress 01/01/73 to 12/30/73

Outputs
Biochemical studies of the resistance mechanism for fireblight in apple cultivars showed that: resistant cultivars contain highest levels of endogenous catecholase, especially in succulent shoots; resistant cultivars contain an unidentified compound; total phenol content of flowers correlates with resistance but that of shoots does not; flavonal and leucoanthocyanin content decreased in susceptible cultivars following inoculation but not in tolerant ones. Specific rootstocks were found to enhance susceptibility to fireblight incertain cultivars. A major reason for lack of winter hardiness in apples is theinability of a cultivar to retain hardiness following warm temps. in midwinter. Propagation tests with blueberries showed that rooting response varied with the selection & morphological development of the shoot. Colt tolerance of flower buds in blueberries was found to be inherited from parents grown & selected under MN conditions. Seedlings surviving -30F were selected. A new large fruited fall bearing raspberry was selected. Summer pruning of apples was foundimpractical under our conditions because fire blight infection was severe at theonly time that flower buds were induced as a result of the treatments.

Impacts
(N/A)

Publications

Progress 01/01/72 to 12/30/72

Outputs
Seedling screening for fireblight enables us to discard up to 70% of the seedlings. Analysis of a diallel crossing scheme indicates that maternal inheritance for susceptibility may be involved. Biochemical studies show that endogenous levels of some flavonoids are correlated with natural infection stages and with differential reactions among cultivars. Polyphenolase activity is similarly related. A standard curve for phenological response to cold tolerance is being used for artificial screening of apple selections. Cold tolerance is lost by unadapted cultivars when they deharden in response to periods of warm temperature. Cold hardy strawberry clones have been identified by artificial freezing. Ninety-six of 108 clones tested were injured at +18mF, 12 survived +14 and 2 survived +10m. Four Beacon dwarf mutants (3 feet to 5 feet) fruited for the 3rd year. Electronic data acquisition programs worked successfully for transferring field data directly to a formated teletype printout for apples, strawberries, raspberries and blueberries. Punched tape was used to access the computer for storage, merger and analysis. Several promising selections were found in strawberries and raspberries. Red color mutants were discovered in Regent, Haralson and Beacon apples.

Impacts
(N/A)

Publications

Progress 01/01/71 to 12/30/71

Outputs
Forty years of apple breeding data was compiled and processed by computer analysis. A portable electronic data recording system was tested and a program developed for field evaluation which eliminates the need for field notes and keypunching. Past, present and future data is being merged to facilitate evaluation and design of crosses for the breeding program. Apple seedlings were grafted to dwarfing rootstocks to induce precocity, reduce generation time,lessen rootstock variability and allow selection under high population density plantings. A gamma induced dwarf mutant Red Haralson was selected and a number of other cultivars were treated. Leaf palisade cell measurement was tested as apreselection tool for dwarf mutants. Several hundred rootstock seedlings from ahardy x dwarf cross were artifically frozen. The dwarfing potential of each is being tested by grafting to a standard cultivar. Seedlings were screened for resistance to fireblight and biochemical studies of varietal resistance are also being conducted. Cold hardiness studies showed that differential thermal analysis is a useful technique to detect an exotherm which correlates strongly with death of the xylem tissue. Xylem tissues were hardier than bark in midwinter, which may explain blackheart injury in apples.

Impacts
(N/A)

Publications

Progress 01/01/70 to 12/30/70

Outputs
Strawberries: The inbred lines have been evaluated and will be used in the breeding program. Yield and size data from the replicated trials showed that Redcoat, Badgerbelle and Minn. 1868, were generally the highest yielding entrieswith acceptable size and quality. Respberries: Three years data from the cultural studies at Morris showed that yields of the summer crop can be doubled as a result of using straw mulch. Apples: Seedling screening for resistance tofireblight was carried out on several thousand seedlings. Preliminary data fromthe inheritance study indicates that whenever a resistant parent is used in a cross two thirds or more of the progeny will be resistant. Preliminary evidenceon the basis of electrophoresis, chromatography and bacterial growth studies indicate that one more phenolic compounds may be implicated in resistance to fireblight. Electrophoretic analysis of malic enzyme showed that banding patterns could be correlated with acidity of the fruit and that the same patterns were found in several different tissues supporting the hypothesis that seedling screening can be a useful tool to predict phenotypic expression in adult trees. A compact tree type, spur bearung Beacon apple was developed fromthe irradiation breeding program. A self compatible apple was found as a consequence of the diallel set up to study resistance to fireblight.

Impacts
(N/A)

Publications

Progress 01/01/69 to 12/30/69

Outputs
Strawberries: Evaluation of the inbred lines is continuing. Seedling screeningstudies were carried out using electrophoretic separation of enzymes to correlate zymograms with phenotypic response. Esterase banding patterns appear promising to distinguish between June and everbearing varieties. Other systems tested vary with developmental stages and do not appear to be suitable. Yield and size data were obtained from six replicated trials, grown on a variety of soil types throughout the state. Trials at Excelsior, Grand Rapids and Morris were successful but results from Elk River and Waseca were poor due to inadquatecontrol of Tarnished Plant Bug. These trials will aid in variety recommendations as well as provide information on genetic adaptation. Raspberries: A diallel system of crosses was made to study the fall bearing character in raspberries. Apples: Approximately 3000 seedlings were screened for resistance to fireblight. A diallel crossing system was initiated to study the inheritance of fireblight resistance and some of these seedlings will be screened in 1970. Electrophoresis was tested to develop a seedling screening technique but no banding system which correlated well with resistance or susceptibility has been found. Two new varieties were introduced. Red Baron should be a good substitute for Wealthy. Honeygold is the first high quality golden apple, similar to Golden Delicious, which can be grown this far north.

Impacts
(N/A)

Publications

Progress 01/01/68 to 12/30/68

Outputs
Small fruits: Two hundred inbred lines of strawberries were selfed and up to 300 individuals per progeny were planted for evaluation and genetic studies. Experiments are planned to study hybrid vigor and combining ability with these progenies. A graduate school grant-in-aid was received to study the use of electrophoresis as a tool for developing objective seedling screening techniques. Accordingly, a critical study of several varieties and their S(1) progenies was conducted to provide phenological data. Six replicated strawberryvariety and advanced selection trials were established to provide data for varietal recommendations and for the breeding program. An N.S.F. summer teachergrant was used to identify sources of resistance to virus infection and to develop virus-free plants of Trumpeter and Earlimore through tissue culture. Five hundred plants from a lowbush x highbush blueberry cross were planted at the Elk River Sand Plain Field. Approximately 15,000 seedlings will be planted in the field next year from crosses made in the winter of 1968. Tree Fruits: With the aid of Dr. B.W. Kennedy, Plt. Path., a screening program to detect fireblight susceptible clones has been developed so that 75% of the susceptible plants can be discarded. This technique will be applied to 6000 seedlings, fromcontrolled crosses, in 1969. Several clones of an apricot and plum hybrid crosshave been found which bloom 7-10 days later than standard apricots.

Impacts
(N/A)

Publications

Progress 01/01/67 to 12/30/67

Outputs
Small Fruits: Screenhouse facilities have been made available to facilitate maintenance of virus-free plant material. Several breeding lines from other breeding programs have been assembled and are being used in hybridization of strawberries, raspberries and blueberries. Variety and advance selection plantings of strawberries and raspberries are being established at the branch stations for regional adaptation tests. Tree Fruits: The stone fruit plantings were evaluated on the basis of previous records and only the most promising selections were propagated. All of the apple selections are being evaluated and the inferior selections will be discarded in the next two years. A fireblight seedling screening program is being developed to screen all future progenies forresistance. The breeding program will also be geared to comply with the Apple Breeders co-operative which is striving for new varities with superior quality and resistance to apple scab, cedar apple rust, mildew and fireblight.

Impacts
(N/A)

Publications