GENETIC IMPROVEMENT OF WOODY PLANTS (TREES AND SHRUBS) FOR ORNAMENTAL USES AND FOOD PRODUCTION.

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1009987
• Project Start Date: Jul 1, 2016
• Project End Date: Jun 30, 2021
• Program Code: [(N/A)]- (N/A)

Recipient Organization
RUTGERS, THE STATE UNIVERSITY OF NEW JERSEY
3 RUTGERS PLZA
NEW BRUNSWICK,NJ 08901-8559

Performing Department
Plant Biology

Non Technical Summary
The nursery and landscape industry is in need of new plants for ornamental purposes that are adapted to the specific climatic and edaphic conditions of the US. This project seeks to breed improved, disease- and pest-resistant woody ornamental plant cultivars of dogwood, hazelnut, holly, and other species that are both attractive, cold and heat hardy, and stress tolerant. These new plants will add to the genetic diversity of plants present in ornamental landscapes and will result is reduced pesticide and fertilizer applications due to their enhanced resistance to pests and disease and envrionmental stress.

Animal Health Component

80%

Research Effort Categories

Basic

20%

Applied

80%

Developmental

0%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
202	2110	1081	100%

Knowledge Area
202 - Plant Genetic Resources;

Subject Of Investigation
2110 - Ornamental trees and shrubs;

Field Of Science
1081 - Breeding;

Keywords

plant breeding

disease resisatnce

dogwood

hazelnut

holly

Goals / Objectives
1. To continue evaluation of the many intra- and interspecific hybrids of different species of Ilex currently under advanced field evaluation, as well as the many intra- and interspecific hybrids developed among and between the three large-bracted species, Cornus florida, C. kousa, and C. nuttallii.2. To utilize the elite germplasm of the many superior hybrids of large-bracted dogwoods already achieved in intra- and inter-specific crosses among and between Cornus florida, C. kousa and C. nuttallii in the continuation of the current conventional program of hybridization, followed by evaluation and selection to obtain superior cultivars. Special effort will be devoted to the development of red-bracted hybrids of C. kousa and/or interspecific hybrids of C. kousa "type", as well as developing a range of unique C. florida cultivars with stable resistance to the incitants of powdery mildew and dogwood anthracnose.3. To develop excellent disease resistant ornamental hazelnut cultivars through intra- and interspecific hybridization. The eastern filbert blight resistant germplasm at Rutgers will also be used to develop hazelnuts for the commercial production of nuts.4. Utilize rapidly advancing molecular biology tools to study genetic diversity and relationships in Cornus, Corylus, and Ilex (and other species) as well as the pathogen Anisogramma anomala and other emerging diseases or pests to best inform breeding procedures and to most effectively and efficiently develop improved cultivars for our region. Also use genomic tools to map genes of interest segregating on populations of these and other taxa.5. Explore other woody ornamental plant species that are under-utilized in the nursery trade and breeding that can be enhanced using the methods developed at the Rutgers University and our research partners worldwide.

Project Methods
Recent selections from the hybridization work with plants of Cornus and of Ilex that have been thoroughly tested by our nursery licensees will be released to commerce as soon as plant-patent-applied-for status has been obtained.After continued evaluation of select seedlings generated in the hybridization work with plants of Cornus and of Ilex, those deemed worthy of final testing will be distributed to our licensed cooperators in New Jersey, Pennsylvania, Maryland, Tennessee, Georgia, Maryland, Oregon, West Virginia, Alabama, Ohio, and California for appraisal of plant vigor, resistance to major insect and disease pests, drought tolerance, growth habit, quality of foliage, flowers and fruit, ease of propagation, and other horticultural characteristics of importance.We will continue to maintain our present collection of Ilex accessions and acquire new germplasm. These plant materials will be used to make new intra- and interspecific hybridizations which we feel have a high probability of yielding seedlings that will prove to be superior to cultivars currently in our performance trials and in commerce. Efforts will be made to "fingerprint" our core collection as funds become available to study relationships and genetic diversity and to help manage and protect future intellectual property rights.We will continue to utilize our extensive collection of the "pink-bracted" cultivars of C. kousa in the trade and our elite collection of unreleased advanced-generation interspecific hybrids of C. kousa × C. florida and C. kousa × C. nuttallii in a traditional program of cross hybridization, evaluation, and selection to produce truly superior clones of red-bracted dogwood of C. kousa "type". Efforts are underway to "fingerprint" our collection to study relationships and genetic diversity and to help manage and protect current and future intellectual property rights.Continue to focus hazelnut breeding efforts on developing novel ornamental hazelnut plants that fill gaps in the nursery industry and landscape such as EFB-resistant, purple-leaf, contorted, cut-leaf, and weeping forms, including combinations of these traits in individual plants worthy of patenting and release. Efforts will also be continued to combine a diversity of genes for EFB resistance into plants that express excellent nut production traits including high yield, kernel to shell ratios of 50% or greater, and kernels that are free of defects and blanch well after roasting.Utilize molecular tools (SSRs, SNPs, mapping, etc.) to study the genetic diversity and relationships in all species held in the Woody Ornamentals collection as resources and funding come available. The data generated will be used to support breeding decisions and protect intellectual property, and the results will be published to support the science of breeding woody plants.

Progress 07/01/16 to 06/30/21

Outputs
Target Audience: Nothing Reported Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Over the course of the 5-year project, multiple undergraduate students were trained per year in the field of woody plant breeding (in the greenhouse, field, and lab), as well as eight PhD students and one Masters degree student (note several are still in progress). Many oral presentation and posters, most resulting in published abstracts (see record of publications) were given by these students each year providing significant experience in effective scientific communication. In addition, we hosted several regional farmer tours of the program and research plots including dozens of individuals visits of farmers and others interested in hazelnut production (food industry, nursery industry, press) and the development of new holly and dogwood cultivars. How have the results been disseminated to communities of interest?Results have laregly been disseminated through field tours at Rutgers, published research papers, and many presentations and posters as listed in each yearly report. Those from 2020 through 2021 are listed below. Invited presentation - Thomas Molnar: A demonstration of grafting techniques for tree propagation. 2020 Tree Symposium hosted by The Friends of The Frelinghuysen Arboretum. November 24, 2020. Invited Seminar (virtual) - Thomas Molnar: Exploring Hazelnuts. 2020 Perennial Farm Gathering hosted by Savanna Institute. https://www.savannainstitute.org/2020-pfg-html/Invite Perennial Farmer Gathering SI update Dec 7, 2020. Jacobs, D.C., J.M. Capik and T.J. Molnar. 2021. Long Term Response of Eastern Filbert Blight Resistant Hazelnut Germplasm in New Jersey. HortScience 56(9) S96 (Abst.) Hlubik, D., J.M. Capik, and T.J. Molnar. 2021. Investigation of Growing Degree Day Requirements of European, American, and Hybrid Hazelnuts in New Jersey. HortScience 56(9) S96 (Abst.) Pfarr Moreau, E., J. Honig, J. Vaiciunas, J.M.Capik, and T. Molnar. 2021. Identification of a Quantitative Trait Locus for Powdery Mildew Resistance in Flowering Dogwood (Cornus florida). HortScience 56(9) S33 (Abst.) Pfarr Moreau, E., R. Di, T. Molnar. 2021. Characterizing Flowering Dogwood MLO Genes. National Association of Plant Breeders Annual Conference; Ithaca, NY Pfarr, E., J. Vaiciunas, C. Kubik, J. Capik, J. Honig, and T. Molnar. (2021) A Genetic Diversity Study of Cornus kousa Cultivars and Wild-Collected Plants. The Northeastern Plant, Pest, and Soils Conference; Gettysburg, PA What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? 1. We continue to evaluate plants held in our breeding nurseries and replicated trials. Over the 5-year project, the large collection of Ilex breeding materials at Rutgers University has been reduced to a small population of elite individuals. The upright pyramidal Ilex crenata interspecific hybrid 'CR195-115' Emerald Lady® Holly (US PP 30 129 P3) continues to be evaluated by several nurseries and members of the Holly Society of America but has not yet been commercialized. Ten additional Ilex selections with complex interspecific genetic backgrounds and diverse, attractive phenotypes were made from the larger basal population. They were propagated and entered into deer browse trials. Unfortunately, the trials showed none were a marked improvement over the currently popular Rutgers' holly Ilex x Red Beauty®. Thus, most were eliminated from the selection trials and possible release. One compact, upright columnar Ilex crenata selection has been propagated and entered into trials for further evaluation where it shows promise as an improvement over plants with 'Sky Pencil' form. More than twenty new hybrid Cornus clones selected from the large populations of hybrid plants at Rutgers University were propagated and closely evaluated across multiple locations including nurseries in TN and OR over the 5 year project. Their evaluation will continue. It is expected that five new high value cultivars will be released from the program in the near future based on these efforts. 2. Dogwood breeding efforts continued throughout the 5-year project amounting to over 8,000 seedlings cycled through evaluation nurseries with over 60 elite individuals identified and propagated for replicated testing. The breeding program is expected to continue and builds on exciting progress made in previous generations. From efforts completed during this project period, Cornus kousa 'Rutpink' Scarlet Fire® dogwood was released and has been commercialized in the nursery and landscape trade in the US and European Union where it is becoming popular and well known for its dark pink floral bracts. Several additional hybrid Cornus breeding selections have performed very well in replicated trials, thus are in the pipeline nearing release. In addition, large populations of Cornus florida seedlings from controlled crosses segregating for resistance and tolerance to the disease powdery mildew from Rutgers selection H4AR15P25 have been created and are undergoing evaluation in field nurseries at Rutgers University. From these populations, we expect to recover an array of exciting disease resistant individuals expressing white, blush, and pink floral bracts and growth habits from dwarf, semi-dwarf, to vigorous tree types. 3. Over the 5-year project, we field-planted and closely evaluated over 45,000 hazelnut seedlings from controlled crosses made at Rutgers and Oregon State University. We continue to evaluate, make selections, and cull poor performing trees from our breeding nurseries that hold seedlings segregating for EFB resistance as well as traits of high importance to commercial nut production and for ornamentals. Cumulative data allowed for the selection and release of eastern filbert blight resistant European hazelnuts 'Raritan', Monmouth', 'Hunterdon', and 'Somerset', with US Plant Patent applications filed in 2019 and commercial propagation and sale of plants initiated in 2020. The first trees of these cultivars were planted on farms in NJ and NY in fall 2020 with much wider distribution in 2021. In addition, four new European hazelnut selections were made that have complementary incompatibility (S) alleles, high levels of EFB resistance and excellent kernel traits that are now undergoing propagation for final stage testing and release. Further, clones of 60 hybrid hazelnut (Corylus americana x C. avellana) selections were identified from large populations and distributed to collaborators in Nebraska, Minnesota, Wisconsin, and Missouri for replicated multi-location testing to identify those adapted to colder, more stressful regions. Finally, five purple leaf hybrid selections were made that are also undergoing propagation for final stage testing and release in the near future. 4. Over the 5-year project, as demonstrated and documented in our cumulative publication and presentation record, we effectively utilized modern genetic tools to better understand the genetic diversity present in dogwoods and hazelnuts including the disease pathogens of eastern filbert blight (Anisogramma anomala) and dogwood powdery mildew (Erysiphe pulchra). We have also sequenced the genome of several isolates of A. anomala and mapped QTLs associated with EFB resistance and other traits in hazelnut and powdery mildew tolerance in dogwood. These efforts have directly supported breeding efforts allowing for better informed decisions to release our current set of cultivars, make new selections for propagation and wider testing, and create new segregating genetically diverse populations expected to more effectively reach breeding goals. 5. Over the course of the 5-year project, no additional genera were placed in a priority position over Cornus and Corylus due to their perceived high demand from the nursery and horticultural industry. We feel we maximized our effectiveness by focusing on Cornus and Corylus where significant and novel progress could be made especially given finite budget situations.

Publications

• Type: Book Chapters Status: Published Year Published: 2021 Citation: Mehlenbacher, S.A. and T.J. Molnar. 2021. Hazelnut (Corylus) breeding. Plant Breeding Reviews. 45:9-141. October 2021 https://doi.org/10.1002/9781119828235.ch2
• Type: Other Status: Published Year Published: 2021 Citation: Muehlbauer, M., J. Capik, and T.J. Molnar. 2021. Choosing plants for a hazelnut orchard in New Jersey. Rutgers University New Jersey Agricultural Experiment Station Cooperative Extension Bulletin E368 https://njaes.rutgers.edu/e368/
• Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Molnar, T.J., Hlubik, D. Mehlenbacher, S.A., J.M. Capik. 2021. Genetic Control of Eastern Filbert Blight Resistance in F2 Generation Hybrid Hazelnut (Corylus americana � C. avellana) Populations. Proceedings of the Thirtieth Annual Rutgers Turfgrass Symposium. Center for Turfgrass Science. School of Environmental and Biological Sciences. Rutgers University. March 18, 2021 Pg. 36
• Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Jacobs, D.C., J.M. Capik and T.J. Molnar. 2021. Long Term Response of Eastern Filbert Blight Resistant Hazelnut Germplasm in New Jersey. HortScience 56(9) S96 (Abst.)
• Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Hlubik, D., J.M. Capik, and T.J. Molnar. 2021. Investigation of Growing Degree Day Requirements of European, American, and Hybrid Hazelnuts in New Jersey. HortScience 56(9) S96 (Abst.)
• Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Pfarr Moreau, E., J. Honig, J. Vaiciunas, J.M.Capik, and T. Molnar. 2021. Identification of a Quantitative Trait Locus for Powdery Mildew Resistance in Flowering Dogwood (Cornus florida). HortScience 56(9) S33 (Abst.)
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Pfarr, E., J. Vaiciunas, C. Kubik, J. Capik, J. Honig, and T.J. Molnar. 2021. Pollen flow in a flowering dogwood (Cornus florida) orchard: using SSRs to develop a quantitative trait loci mapping population. Acta Horticulturae, In Press.

Progress 10/01/19 to 09/30/20

Outputs
Target Audience:Prospective hazelnut growers and nursery operators and owners as well as chefs and restaurant owners in New Jersey, NY and PA were reached as well as the agricultural scientific community through multiple presentations and posters provided by me and my students (graduate and undergraduate) at scientific meetings and grower tours. Virtual meetings were held starting in March 2020. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Six undergraduate students (Dan Jacobs, Ash Dunley, Adam D'angelo, Fiona Sargeant, Stephanie Aponte, and Catherine Worth) were trained in plant breeding, as well as six PhD students (Alanna Cohen, Justin Lombardoni, David Hlubik, Matt Milburn, Erin Pfarr, and Alex Mayberry) and one Masters degree student (Emil Milan). Adam D'Angelo completed a G.H. Cook Senior thesis in 2020 on eastern filbert blight in hazelnuts. A PostDoctoral fellow assisted in the lab. Eight oral presentation or posters most resulting in published abstracts were given by these students in 2019. In addition, we hosted regional farmer tour of hazelnut program and research plots on September 18, 2019. This meeting included 42 guests representing 22 farms. How have the results been disseminated to communities of interest?Results have been disseminated through field tours at Rutgers, published research papers, and by the following presentations and posters: Cohen, A.B., G. Cai, D. Price, L. He, N. Zhang, T.J. Molnar and B.I. Hillman. 2020. Genomic analysis of the Eastern Filbert Blight fungus, Anisogramma anomala, provides insight to pathogen biology. American Phytopathological Society. https://apsnet.confex.com/apsnet/2020/meetingapp.cgi/Paper/17157 Hlubik, D., J.M. Capik, S. Mehlenbacher, T.J. Molnar. 2020. Eastern Filbert Blight Response of F1 Corylus americana x C. avellana Selections and F2 progenies. HortScience 55(9) S106. (Abstr.) Hlubik, D., J.M. Capik, T.J. Molnar. 2020. Investigating Chilling Requirements of European Hazelnut and Hybrid Hazelnut Selections in New Jersey. HortScience 55(9) S276. (Abstr.). Hlubik, D. A. D'Angelo, J.M. Capik, and T.J. Molnar. 2020. Investigation of Nut Quality in Interspecific Hybrid Hazelnuts. HortScience 55(9) S443. (Abstr.). Lombardoni, J.J., J. Honig, J. Vaiciunas, and T. Molnar. 2020. Segregation of Eastern Filbert Blight (Anisogramma anomala) Disease Response and Single Nucleotide Polymorphism Markers in Three Hybrid European-American Interspecific Hazelnut Populations. HortScience 55(9) S105. (Abstr.) Pfarr, E., J. Vaiciunas, J.M. Capik, and T.J. Molnar. 2020. Powdery Mildew Response of a Flowering Dogwood (Cornus florida) Quantitative Trait Loci Mapping Population. HortScience 55(9) S122. (Abstr.) Mayberry, A., S.A. Mehlenbacher, J.M. Capik, and T.J. Molnar. 2020.Benefits and Drawbacks of American Hazelnut Pollenizers to Expand the Commercial Hazelnut Production Range. 55(9) S292. (Abstr.) Invited presentation T. Molnar: Hazelnuts in the Northeast: Overview and Update (part of workshop "Growing Edible Tree Nuts in the Northeast". 8th Annual Lehigh Valley Watershed Conference: Navigating Clean Water Science. October 15, 2019. Lehigh University, Bethlehem, PA. Invited presentation T. Molnar: Exciting progress breeding Cornus and Corylus at Rutgers University. 2019 Tree Symposium at the Frelinghuysen Arboretum. November 9, 2019. Invited presentation T. Molnar: Hazelnuts! A new crop for the northeast. Stone Barns Center for Food and Agriculture presentation to Staff. Also presentation on hazelnut at Blue Hill restaurant Chef's meeting. November 11, 2109. Invited presentation T. Molnar: Rutgers University Tree Breeding Program: Here Come the Hazelnuts (for Nuts) and Next Steps after Scarlet Fire Dogwood. Southern Nursery Association Plants Conference. January 7, 2020. Baltimore, MD Invited presentation T. Molnar: Rhododendron Society of the United States Princeton Chapter. Rutgers University Tree Breeding Program: hazelnuts and dogwoods. Feb. 16, 2020. Rutgers University. What do you plan to do during the next reporting period to accomplish the goals?We will continue to follow the systematic methods developed over the more than 4-decade history of the Rutgers woody ornamental breeding program to enhance germplasm and develop and identify superior landscape plants and hazelnuts for nut production and ornamentals. We will increase our use of molecular biology approaches to support understanding of genes for disease resistance, ornamental traits, and traits associated with nut production. We will bolster our student training and outreach efforts associated with the breeding programs to provide greater opportunities for training and professional development.

Impacts
What was accomplished under these goals? 1. We continue to evaluate plants held in our breeding nurseries and replicated trials. The upright pyramidal Ilex crenata interspecific hybrid 'CR195-115' Emerald Lady® Holly (US PP 30 129 P3) continues to be evaluated by several commercial nurseries and members of the Holly Society of America. Ten other Ilex selections with complex interspecific genetic backgrounds and diverse, attractive phenotypes have been propagated and entered into deer browse trials at Rutgers. One additional compact, upright columnar Ilex crenata selection has been propagated and entered into trials for further evaluation. More than twenty hybrid Cornus clones were distributed as bud wood in August 2020 to a select group of nurseries to evaluate their propagation aspects (budding success, vigor, branching, freedom from disease, etc.) and adaptation and performance in different regions of the US. 2. Selection C. florida H4AR15P25 shows excellent resistance to powdery mildew. The resistance holds up in clones across multiple locations and appears to be heritable although its genetic control has yet to be elucidated (studies are underway). In 2020, 32 bi-parental crosses were made via hand pollination (each repeated 3 to 4 times) between powdery mildew resistant Cornus florida accession H4AR15P25 and those with a range of PM response (resistant/tolerant through highly susceptible) and a range floral bract colors (white, blush to dark pink/red). This population will form a foundation for genetic study and mapping. Over 2,300 hybrid seeds were harvested and placed into cold stratification in November 2020. We field planted over 2,000 seedlings from crosses made in 2019 with a focus on dark-pink bracted hybrid dogwoods and kousa types. The breeding nurseries established in 2016 and older have reached flowering age are yielding very interesting individual plants that merit clonal propagation and replicated, multi-location testing. 3. We field-planted over 5,000 hazelnut seedlings from controlled crosses made in 2019 at Rutgers and Oregon State University. We continue to evaluate, make selections, and cull poor performing trees from our breeding nurseries that hold over 15,000 seedlings segregating for EFB resistance as well as traits of high importance to commercial nut production and ornamentals. Cumulative data allowed for the selection and release of 'Raritan', Monmouth', 'Hunterdon', and 'Somerset', with US Plant Patent applications filed in 2019 and commercial propagation and sale of plants initiated in 2020. The first trees of these cultivars were planted on farms in NJ and NY in fall 2020. In addition, clones of around 60 hybrid hazelnut selections were sent to collaborators in Nebraska, Minnesota, and Missouri for replicated multi-location testing. 4.We studied the progeny of three interspecific hybrid crosses, each between a different American hazelnuts (OSU 403.040, OSU 533.069, CCOR 710.001) and a shared European parent, 'Tonda di Giffoni'. We evaluated the progenies for disease response including proortion of diseased wood. We also performed DNA extraction, library preparation, and paired-end next-generation sequencing on an Illumina HiSeq platform on the plants. We then processed raw reads from sequencing using Stacks v1.47 for single nucleotide polymorphism (SNP) discovery. Results showed each progeny segregated for disease response largely following a normal distribution of disease expression, which indicated multigenic inheritance of resistance/tolerance. The OSU 533.069, OSU 403.040, and CCOR 710.001 progenies produced 36,292, 36,441, and 36,790 SNPs, respectively, at the end of the Stacks pipeline. The results from this study suggest there is both considerable variation in disease response across the progeny and a vast number of SNPs segregating in each population. Progeny of OSU 403.040 was analyzed and three QTLs associated with EFB resistance identified by Ronald Revord and published in his PhD dissertation (Revord, 2019). We are using the phenotype data and thousands of SNP markers to map QTLs associated with EFB resistance/tolerance in the other two progeny and will publish the results of all three in a single manuscript. We are also collecting detailed nut and kernel quality trait data for these progeny as well as data on bloom and bud break phenology. We plan to map QTLs associated with nut traits and bloom and budbreak in the three populations. We completed a study on EFB resistance in C. americana x C. avellana hybrids (Revord et al., 2020a) whose results enhances our understanding of the genetic control of disease resistance derived from our native hazelnut species (both horizontal and vertical resistance and likely a combination of both is present across the available germplasm). Controlled crosses were made between new resistant accessions from foreign introductions and susceptible parents to develop new mapping populations to study disease response and inheritance of resistance. Many crosses were also made to develop progenies segregating for two genes from parents known to transmit single R genes that are holding up to high disease pressure in NJ. 38 clonal F1 hybrid hazelnut selections from Oregon were evaluated for disease response in the field in New Jersey also including a subset of their F2 progeny. A range of responses was observed in the clones from moderately tolerant to highly tolerant to resistant. Several modes of inheritance were observed in the F2 progeny. This included normal distribution characteristic of quantitative (multi-genic) inheritance; bimodal distribution, indicative of control by one or two major genes; and some progenies that appear to have a combination of major and minor genes present for disease resistance. Transgressive segregation (seedlings with better disease response than either parent) was observed in many progenies, which suggests additive genetic control is present and that it should be possible to develop plants with even higher levels of tolerance/resistance. We completed a study on the genetic diversity present in a subset of the C. americana collection present at Rutgers (Revord et al., 2020b), which identifed 51 genotypes as part of a core set of individuals. This collection was also evaluated for EFB response and reported in Revord et al. (2020a). The collection continues to be studied for nut and kernel traits and phenology of bloom and budbreak. The use of C. americana as a pollenizer from European hazelnut continues to be evaluated. The genome assembly and analysis of the Oregon isolate of A. anomala has been completed. Assembly statistics and genome features were summarized and a report on the genomic analysis was presented at the virtual 2020 American Phytopathological Society Annual Meeting. Consistent with previous findings, repetitive regions accounts for approximately 88% of the genome. The majority of these elements are Class I Long Terminal Repeats (LTR) retrotransposons. Further, we performed an Orthofinder analysis to identify gene families shared with related fungal pathogens. 2,438 single-copy orthologous gene families and their corresponding protein sequences were used to build a super-gene phylogeny. In addition, we have identified the genetic basis for homothallism through analysis of the mating type locus. Homologs for both MAT1-1 and MAT2-1 idiomorphs have been identified in the A. anomala genome. Repeat-induced point (RIP) mutation analysis was also performed and dinucleotide frequencies were observed consistent with RIP-like mutations. 5. Work continues towards identification of additional genera to develop in the program, although progress has been slow since a majority of efforts continue to be placed on Cornus and Corylus where a perceived demand from the nursery and horticultural industry is currently high

Publications

• Type: Journal Articles Status: Published Year Published: 2020 Citation: Revord, R.S., S.T. Lovell, J.M. Capik, S.A. Mehlenbacher, and T.J. Molnar. 2020. Eastern Filbert Blight Resistance in American and Interspecific Hybrid Hazelnuts. Journal of the American Society for Horticultural Science. 145:162-173. https://doi.org/10.21273/JASHS04732-19
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Revord, R.S., S.T. Lovell, P. Brown, J.M. Capik, and T.J. Molnar. 2020. Using Genotyping-By-Sequencing Derived SNPs to Examine Genetic Structure and Identify a Core Set of Corylus americana germplasm. 2020. Tree Genetics and Genomes. 16:65 https://doi.org/10.1007/s11295-020-01462-y
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Lombardoni, J.J., J.A. Honig, J. Vaiciunas, C. Kubik, J. Capik, S. Mehlenbacher and T.J. Molnar. 2018. Evaluation of European hazelnut (Corylus avellana) genetic diversity using a genotyping-by-sequencing approach. Acta Hort. 1280:11-16. DOI 10.17660/ActaHortic.2020.1280.2
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Molnar, T.J. 2018. Breeding Powdery Mildew Resistant Dogwoods and More at Rutgers University. Proceedings of the International Plant Propagators Society Combined Proceedings. 68:385-395
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Molnar, T.J., E. Milan, and J.M. Capik. 2020. Introducing the new Rutgers University Hazelnut Cultivars Raritan, Monmouth, Somerset, and Hunterdon. Proceedings of the Twenty-ninth Annual Rutgers Turfgrass Symposium. Center for Turfgrass Science. School of Environmental and Biological Sciences. Rutgers University. January 10, 2020 Pgs. 47-49
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Cohen, A.B., G. Cai, D. Price, L. He, N. Zhang, T.J. Molnar and B.I. Hillman. 2020. Genomic analysis of the Eastern Filbert Blight fungus, Anisogramma anomala, provides insight to pathogen biology. American Phytopathological Society. https://apsnet.confex.com/apsnet/2020/meetingapp.cgi/Paper/17157
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Lombardoni, J.J., J. Honig, J. Vaiciunas, and T. Molnar. 2020. Segregation of Eastern Filbert Blight (Anisogramma anomala) Disease Response and Single Nucleotide Polymorphism Markers in Three Hybrid European-American Interspecific Hazelnut Populations. HortScience 55(9) S105. (Abstr.)
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2020 Citation: Hlubik, D., J.M. Capik, S. Mehlenbacher, T.J. Molnar. 2020. Eastern Filbert Blight Response of F1 Corylus americana x C. avellana Selections and F2 progenies. HortScience 55(9) S106. (Abstr.)
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Pfarr, E., J. Vaiciunas, J.M. Capik, and T.J. Molnar. 2020. Powdery Mildew Response of a Flowering Dogwood (Cornus florida) Quantitative Trait Loci Mapping Population. HortScience 55(9) S122. (Abstr.)
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Mayberry, A., S.A. Mehlenbacher, J.M. Capik, and T.J. Molnar. 2020.Benefits and Drawbacks of American Hazelnut Pollenizers to Expand the Commercial Hazelnut Production Range. 55(9) S292. (Abstr.)
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Hlubik, D. A. DAngelo, J.M. Capik, and T.J. Molnar. 2020. Investigation of Nut Quality in Interspecific Hybrid Hazelnuts. HortScience 55(9) S443. (Abstr.).

Progress 10/01/18 to 09/30/19

Outputs
Target Audience:Prospective hazelnut growers and nursery operators and owners as well as chefs and restaurant owners in New Jersey, NY and PA were reached as well as the agricultural scientific community through multiple presentations and posters provided by me and my students (graduate and undergraduate) at scientific meetings and grower tours. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Six graduate students are or have been associated with the project over the past reporting year (David Hlubik, Erin Pfarr, Justin Lombardoni, David Hlubik, Emil Milan, Matt Milburn, Ronald Revord, and Alex Mayberry) as well as three undergraduate. Ronald Revord completed his PhD in 2019 at the Univ. of Illinois in close collaboration with Thomas Molnar at Rutgers University (title: Towards the Exploitation of the American Hazelnut (Corylus americana). Nine oral presentation or posters most resulting in published abstracts were given by these students in 2019. They attended meetings in Oregon, Georgia, Maryland and Nevada. One student traveled to Oregon State University to learn how to identify S-alleles of hazelnuts using florescent microscopy. How have the results been disseminated to communities of interest?Results have been disseminated through field tours at Rutgers, published research papers, and by the following presentations and posters in 2019: Oral presentation by Erin Pfarr: Pfarr, E.; J. Vaiciunas; C. Kubik; J. Capik; J. Honig; and T. Molnar. January 2019. Using Simple Sequence Repeat (SSR) Markers and Open Pollinated Seedlings for Quantitative Trait Loci (QTL) Mapping Population Development in Cornus florida. The Northeastern Plant, Pest, and Soils Conference; Hunt Valley, MD. Proceeding Volume 4, The NORTHEASTERN PLANT, PEST, AND SOILS CONFERENCE January 8-10, 2019 Oral presentation by Alex Mayberry: Mayberry, A. J. Capik, and T.J. Molnar. 2019. Establishing a core collection of Corylus americana from wild germplasm for hazelnut breeding and pollenizer efforts. The Northeastern Plant, Pest, and Soils Conference; Hunt Valley, MD. Proceeding Volume 4, The NORTHEASTERN PLANT, PEST, AND SOILS CONFERENCE January 8-10, 2019. Invited Presentation by Thomas Molnar: Nuts for New Jersey. NOFA New Jersey Annual conference. January 27, 2019. https://nofanj.org/workshop?w_id=114 (30 people) Invited presentation by Thomas Molnar: Corylus americana: An Incredible Edible Native Plant and the Key to Expanding Commercial Hazelnut Production in Colder Regions. Native plants in the landscape conference. www.millersvillenativeplants.org. June 6, 2019 (around 150 people) Hosted tour: Thomas Molnar provided walking tour and discussion of dogwood breeding nurseries for the New York Hortus Club, May 21, 2019. Around 30 people. Poster: Dunlevy, A., M.P. Gandler, D. Hlubik, J.M. Capik, and T. J. Molnar. 2019. Examining Pathogenic Variation and Host Plant Response to Eastern Filbert Blight in Hazelnut Cultivars Protected By the 'Gasaway' Resistance Gene HortS54(9) Se 238. (Abstr.) Poster: Hlubik, D., J.M.Capik, A. D'Angelo, A. Mayberry, and T.J. Molnar. 2019. Evaluation of Hybrid Hazelnut Phenology to Determine Usefulness As Pollenizers. HortS54(9) Se 329. (Abstr.) Oral presentation by Erin Pfarr: Pfarr, E.; J. Vaiciunas; C. Kubik; J. Capik; J. Honig; and T. Molnar. 2019. Genotyping-by-Sequencing Diversity Study of Big-Bracted Dogwood (Cornus ssp.) Cultivars and Wild-Collected Accessions. HortS54(9) Se 72. (Abstr.) Oral Presentation by Alex Mayberry: Mayberry, A. J. Capik, S.A. Mehlenbacher, and T.J. Molnar. 2019. Evaluating American Hazelnuts for Use As Cold Hardy Pollenizers in European Hazelnut Orchards. HortS54(9) Se 176. (Abstr.). Oral Presentation by Megan Muehlbauer: Muehlbauer, M., T.J. Molnar, J. Honig, and J.M. Capik. 2019. Evaluation and Correlation of Kernel Characteristics and Eastern Filbert Blight Response to Genetic Backgrounds of Hazelnut Germplasm from Turkey and the Baltic Region. HortS54(9) Se 177. (Abstr.) Thomas Molnar hosted regional farmer tour of Hazelnut program and research plots. September 18, 2019. 42 guests representing 22 farms. Four hour tours and presentation: Building on breeding advances to create new opportunities for farmers and beyond (42 people) Invited presentation by Thomas Molnar: Hazelnuts in the Northeast: Overview and Update (part of workshop "Growing Edible Tree Nuts in the Northeast". 8th Annual Lehigh Valley Watershed Conference: Navigating Clean Water Science. October 15, 2019. Lehigh University, Bethlehem, PA. (30 people) Invited presentation by Thomas Molnar: Exciting progress breeding Cornus and Corylus at Rutgers University. 2019 Tree Symposium at the Frelinghuysen Arboretum. November 9, 2019. https://www.arboretumfriends.org/2019-tree-symposium-0 (75 people) What do you plan to do during the next reporting period to accomplish the goals?We will continue to follow the systematic methods developed over the more than 4-decade history of the woody ornamental breeding program to enhance germplasm and develop and identify superior landscape plants. We will increase our use of molecular biology approaches to support understanding of genes for disease resistance, ornamental traits, and traits associated with nut production. We will bolster our student training and outreach efforts associated with the breeding programs.

Impacts
What was accomplished under these goals? 1: We continue to evaluate plants held in our breeding nurseries originally developed and selected by Dr. Elwin Orton prior to 2006. We recently identified one interspecific hybrid Ilex selection with a unique upright form that we named 'CR195-115' Emerald Lady® Holly for which a U.S. plant patent was awarded Jan. 22, 2019 (US PP 30 129 P3). The cultivar is being evaluated by several commercial nurseries and members of the Holly Society of America. Ten other Ilex selections with unique phenotypes have been propagated for further testing including their response to deer browse. More than twenty hybrid Cornus clones were distributed as bud wood in August 2019 to a select group of nurseries to evaluate their propagation aspects (budding success, vigor, branching, freedom from disease, etc.) and adaptation and performance in different regions of the US. 2: In 2019, we made over 500 hand pollination between powdery mildew resistant Cornus florida accessions and those with a range of floral bract colors (white to dark pink/red) and other ornamental attributes. Over 1000 seeds were harvested and placed into cold stratification in December 2019. We field planted over 1500 seedlings from crosses made in 2018 with a focus on dark-pink bracted hybrid dogwoods and kousa types. The breeding nurseries are yielding very interesting individual plants that merit clonal propagation and replicated, multi-location testing. One selection from the Rutgers dogwood breeding program, C. florida H4AR15P25, shows excellent resistance to powdery mildew. The resistance holds up in clones across multiple locations and appears to be heritable. The quantitative trait loci (QTLs) underlying this resistance will be investigated and mapped in a pseudo F2 population using genotyping by sequencing (GBS)-derived single nucleotide polymorphism markers. To expedite population development, open-pollinated seeds were harvested from H4AR15P25 grown in an isolated crossing block of 16 PM-susceptible pollen parents. Six hundred thirty-six seedlings were genotyped with eight SSR markers to determine pollen parents and study pollen flow within the crossing block. Using CERVUS 3.0, the pollen parents of 531 seedlings were assigned with 95% confidence and 52 seedlings with 80% confidence. Interestingly, 53 seedlings could not be assigned to any of the pollen parents, with 31 possessing one or more alleles that weren't present in the pollen parents, indicating pollen flow from outside sources. In general, distance from the mother tree, H4AR15P25, was the main factor influencing the proportion of progeny assigned to a given pollen parent. A full-sibling population of 190 seedlings was assembled with susceptible pollen parent H4AR15P28. This C. florida population is being genotyped using GBS and evaluated for PM response at two and three years of age (2019 and 2020). Additional crosses are being evaluated in the study and will be used in future mapping and QTL confirmation. The final goals are to better understand inheritance of the source of PM resistance and to subsequently use QTLs for PM resistance to aid in marker assisted selection in the Rutgers dogwood breeding program. 3: We field-planted over 4,000 hazelnut seedlings from controlled crosses made in 2018 at Rutgers and Oregon State University. We continue to evaluate, make selections, and cull poor performing trees from our breeding nurseries that hold over 12,000 seedlings segregating for EFB resistance as well as traits of high importance to commercial nut production. Cumulative data allowed for the selection of four genotypes in 2017 for clonal propagation through micro-propagation for much wider multi-location yield testing. Multi-location farm trials will be planted in 2020 in NJ, PA and NY. In addition, clones of 30 F1 hybrid hazelnut selections were sent to collaborators in Nebraska for testing. Four Plant Patent applications have been applied for in 2019 (Corylus avellana 'Raritan', 'Monmouth', 'Somerset', and 'Hunterdon'). 4: We continue to study EFB resistance and segregation patterns in populations derived from multiple sources of resistance. In a recent study, we examined six sources of EFB resistance: C. avellana 'Ratoli' and OSU 495.072, C. americana 'Rush' and 'Winkler', C. heterophylla 'Oygoo', and the Turkish tree hazel (C. colurna) hybrid 'Grand Traverse'. Genotypes representing each resistance source were crossed with susceptible parents resulting in a total of 2,947 seedlings in 46 full-sib progenies. They were field planted at Rutgers and exposed to EFB over six or more years. Their disease response was evaluated on a scale of 0 to 5 (0 = resistant, 5 = highly susceptible) and segregation patterns were examined. Final results showed that all sources transmitted resistance to their offspring in a dominant manner. Interestingly, segregation patterns compiled by resistance source were relatively similar, with about 50% of the plants showing resistance (rating = 0). The remaining trees in each group were characterized as susceptible, with a majority rated as 4 or 5. These results suggest control by one or a limited number of genes, agree with previous linkage mapping work for several of the sources, and show that resistance has been effective when exposed to multiple isolates of A. anomala. Our results demonstrate transmission of resistance at a high level and suggest that these sources hold considerable promise for breeding plants adapted to New Jersey and other parts of the eastern U.S. Building on previous work identifying new sources of EFB resistance, research was undertaken to develop a genetic linkage map using double digestion restriction site associated DNA sequencing (ddRADseq) and identify quantitative trait loci (QTL) markers associated with EFB resistance from the resistant selection Rutgers H3R07P25 from southern Russia. A mapping population composed of 119 trees was evaluated where the EFB fungus is endemic, exhibits high disease pressure, and has a high level of genetic diversity. The completed genetic linkage map included a total of 2217 markers and spanned a total genetic distance of 1383.4 cM, with an average marker spacing of 0.65 cM. A single QTL region associated with EFB resistance from H3R07P25 was located on linkage group (LG) 2 and was responsible for 72.8% of the phenotypic variation observed in the study. Based on its LG placement, origin, and disease response in the field, this resistance source is different from the 'Gasaway' source located on LG6. The current results, in combination with results from previous research, indicate that the H3R07P25 source is likely exhibiting resistance to a broader range of naturally occurring A. anomala isolates. As such, H3R07P25 will be important for the development of new hazelnut germplasm that combines EFB resistance from multiple sources in a gene pyramiding approach. A completed study published in 2019 of Anisogramma anomala using 18 SSR loci showed the pathogen to exhibit considerable genetic diversity across its native range. Current work is aimed at using these tool and a better understanding of the fungus to elucidate interaction with single R genes starting with the Gasaway source of resistance. 5: Work continues towards identification of additional genera to develop in the program, although progress has been slow since a majority of efforts continue to be placed on Cornus and Corylus where a perceived demand from the nursery and horticultural industry is currently high.

Publications

• Type: Journal Articles Status: Published Year Published: 2019 Citation: Revord, R, S. Lovell, T. Molnar, K. Wolz, and C. Mattia. 2019. Germplasm Development of Underutilized Temperate U.S. Tree Crops. Sustainability. 11. 1546. 10.3390/su11061546.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Muehlbauer, M.F., Tobia J., Honig, J.A., Zhang N., Hillman, B.I., Morey Gold, K., and Molnar, T.J. 2019. Population differentiation within Anisogramma anomala in North America. Phytopathololgy. 109:1074-1082. Published Online: 29 Apr 2019 https://doi.org/10.1094/PHYTO-06-18-0209-R
• Type: Journal Articles Status: Published Year Published: 2019 Citation: T.J. Molnar, P. Engel, S. Mehlenbacher, and J. Capik. 2019. Multiple sources of eastern filbert blight resistance provide breeding utility in New Jersey. Journal of the American Pomological Society. 73: 178-192 2019
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Lombardoni, J., J.A. Honig, C. Kubik, J. Vaiciunas, J. Capik, S.A. Mehlenbacher, and T. Molnar. 2018. Analysis of European hazelnut (Corylus avellana) Germplasm Diversity Through Genotyping By Sequencing. Proceedings of the 3rd Northeastern Plant, Pest, and Soils Conference 3:25 https://www.newss.org/wp-content/uploads/2018-NEPPSC-Proceedings_FINAL.pdf (Annual Meeting of the Northeastern branch of the American Society for Horticultural Science. Philadelphia, PA, Jan. 6, 2018)
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Gandler, M., E. Milan, J.M. Capik, and T. Molnar. 2018. Long-term Observation of Resistance Sources to Eastern Filbert Blight in New Jersey. Proceedings of the 3rd Northeastern Plant, Pest, and Soils Conference 3:28 https://www.newss.org/wp-content/uploads/2018-NEPPSC-Proceedings_FINAL.pdf (Annual Meeting of the Northeastern branch of the American Society for Horticultural Science. Philadelphia, PA, Jan. 6, 2018)
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Hlubik, D., H. Patel, J. Capik, J.E. Simon, and T.J. Molnar. Analysis of Volatile Diversity in European Hazelnuts and other Corylus Species Using GC/MS Static Headspace. Proceedings of the 3rd Northeastern Plant, Pest, and Soils Conference 3:26 https://www.newss.org/wp-content/uploads/2018-NEPPSC-Proceedings_FINAL.pdf (Annual Meeting of the Northeastern branch of the American Society for Horticultural Science. Philadelphia, PA, Jan. 6, 2018)
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Pfarr, E., J. Capik, and T. Molnar. 2018. Preliminary Powdery Mildew Response of Big-Bracted Dogwood Cultivars (Cornus spp.) in New Jersey. Proceedings of the 3rd Northeastern Plant, Pest, and Soils Conference 3:27 https://www.newss.org/wp-content/uploads/2018-NEPPSC-Proceedings_FINAL.pdf (Annual Meeting of the Northeastern branch of the American Society for Horticultural Science. Philadelphia, PA, Jan. 6, 2018)
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Mayberry, A., J. Capik, E. Milan, D.J. Hlubik, M. Gandler, and T.Molnar. 2018. Flowering phenology and phenotypic characterization of commercially valuable traits in wild American hazelnut (Corylus americana). Proceedings of the 3rd Northeastern Plant, Pest, and Soils Conference 3:47 https://www.newss.org/wp-content/uploads/2018-NEPPSC-Proceedings_FINAL.pdf (Annual Meeting of the Northeastern branch of the American Society for Horticultural Science. Philadelphia, PA, Jan. 6, 2018
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Mayberry, A., J.A. Honig, J. Capik, J.N. Vaiciunas, and T.J. Molnar. 2018. Determining chloroplast haplotype variation of wild American hazelnut. HortScience 53(9):S44 (Abstr.).
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Gandler, M. E. Milan, J.M. Capik, and T. Molnar. 2018. Long-Term Observation of Resistance Sources to Eastern Filbert Blight in New Jersey. HortScience 53(9):S331 (Abstr.).
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Pfarr, E., J. Honig, J. Vaiciunas, C. Kubik, J.M. Capik, and T. Molnar. 2018. Preliminary Results of a Genotyping By Sequencing Diversity Study of Big-Bracted Dogwood (Cornus spp.) Cultivars. HortScience 53(9):S305 (Abstr.).
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Molnar, T.J., J. Tobia, M.F. Muehlbauer, J.A. Honig, B.I. Hillman, and J.M. Capik. 2019. Eastern filbert blight of hazelnuts: a complicated nemesis. Pg. 40. Proceedings of the Twenty-eight Annual Rutgers Turfgrass Symposium. Center for Turfgrass Science. School of Environmental and Biological Sciences. Rutgers University. January 18, 2019
• Type: Theses/Dissertations Status: Published Year Published: 2019 Citation: Revord, R.S. 2019. Towards the exploitation of the American hazelnut. University of Illinois at Urbana-Champaign. Ph.D. dissertation, 155 pp. https://rucore.libraries.rutgers.edu/rutgers-lib/53746/
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Pfarr, E.; J. Vaiciunas; C. Kubik; J. Capik; J. Honig; and T. Molnar. January 2019. Using Simple Sequence Repeat (SSR) Markers and Open Pollinated Seedlings for Quantitative Trait Loci (QTL) Mapping Population Development in Cornus florida. The Northeastern Plant, Pest, and Soils Conference; Hunt Valley, MD. Proceeding Volume 4, The NORTHEASTERN PLANT, PEST, AND SOILS CONFERENCE January 8-10, 2019
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Mayberry, A. J. Capik, and T.J. Molnar. 2019. Establishing a core collection of Corylus americana from wild germplasm for hazelnut breeding and pollenizer efforts. The Northeastern Plant, Pest, and Soils Conference; Hunt Valley, MD. Proceeding Volume 4, The NORTHEASTERN PLANT, PEST, AND SOILS CONFERENCE January 8-10, 2019.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Dunlevy, A., M.P. Gandler, D. Hlubik, J.M. Capik, and T. J. Molnar. 2019. Examining Pathogenic Variation and Host Plant Response to Eastern Filbert Blight in Hazelnut Cultivars Protected By the Gasaway Resistance Gene HortS54(9) Se 238. (Abstr.)
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Hlubik, D., J.M.Capik, A. DAngelo, A. Mayberry, and T.J. Molnar. 2019. Evaluation of Hybrid Hazelnut Phenology to Determine Usefulness As Pollenizers. HortS54(9) Se 329. (Abstr.)
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Pfarr, E.; J. Vaiciunas; C. Kubik; J. Capik; J. Honig; and T. Molnar. 2019. Genotyping-by-Sequencing Diversity Study of Big-Bracted Dogwood (Cornus ssp.) Cultivars and Wild-Collected Accessions. HortS54(9) Se 72. (Abstr.)
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Mayberry, A. J. Capik, S.A. Mehlenbacher, and T.J. Molnar. 2019. Evaluating American Hazelnuts for Use As Cold Hardy Pollenizers in European Hazelnut Orchards. HortS54(9) Se 176. (Abstr.).
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Muehlbauer, M.,T.J. Molnar, J. Honig, and J.M. Capik. 2019. Evaluation and Correlation of Kernel Characteristics and Eastern Filbert Blight Response to Genetic Backgrounds of Hazelnut Germplasm from Turkey and the Baltic Region. HortS54(9) Se 177. (Abstr.)
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Honig, J. A., M.F. Muehlbauer, J.M. Capik, C. Kubik, J. N. Vaiciunas, S. A. Mehlenbacher, and T. J. Molnar. 2019. Identification and Mapping of Eastern Filbert Blight Resistance Quantitative Trait Loci in European Hazelnut Using Double Digestion Restriction Site Associated DNA Sequencing. Journal of the American Society for Horticultural Science. 144: 295-304 DOI: https://doi.org/10.21273/JASHS04694-19

Progress 10/01/17 to 09/30/18

Outputs
Target Audience:Prospective hazelnut growers and nursery operators and owners in New Jersey and New York were reached as well as the agricultural scientific community through multiple presentations and posters provided by me and my students (graduate and undergraduate) at scientific meetings and grower tours. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Seven graduate students are or have been active participants in the project over the past reporting year (Megan Muehlbauer, David Hlubik, Erin Pfarr, Justin Lombardoni, Michael Gandler, Emil Milan, and Alex Mayberry) as well as five undergraduate. Megan Muehlbauer completed her PhD in May 2017 on hazelnut breeding and genetics; More than 10 oral presentation or abstracts were given by these student in 2017 and 2018. How have the results been disseminated to communities of interest?Results have been disseminated through field tours at Rutgers and by the following presentations and posters: Poster: Capik J. and T.J. Molnar. 2017. An update on sources of resistance to eastern filbert blight disease of hazelnuts in New Jersey. HortScience 52(9):S5. (Abstr.) [Originally published in: Proc. (Vol. 2). The Northeastern Plant, Pest, and Soils Conference. Flessner, M.L, (ed.). 2017]. Oral Presentation: Mayberry, A., J. Capik, and T.J. Molnar. 2017. Phenotypic characterization of wild american hazelnut (Corylus americana) germplasm to support future hybrid hazelnut breeding. HortScience 52(9):S3. (Abstr.) [Originally published in: Proc. (Vol. 2). The Northeastern Plant, Pest, and Soils Conference. Flessner, M.L, (ed.). 2017]. Poster: Muehlbauer, M., D. Hlubik, and T.J. Molnar. 2017. Characterization of the effects of hybrid hazelnut pollenizers (Corylus americana x C. avellana) on the oil content and profiles of several European hazelnut (C. avellana) cultivars. HortScience 52(9):S6. (Abstr.) [Originally published in: Proc. (Vol. 2). The Northeastern Plant, Pest, and Soils Conference. Flessner, M.L, (ed.). 2017]. Poster: Hlubik. D., M. Muehlbauer, J. Capik, J. Simon., and T.J. Molnar. 2017. Effect of Pollen Parents on Oil Characteristics in European Hazelnuts. HortScience 52(9):247. (Abstr.) Poster: Tobia, J., M. Muehlbauer, J. Honig, J. Pscheidt, and T.J. Molnar. 2017. Cluster analysis of Anisogramma anomala isolates collected from the Pacific Northwest and New Jersey. (Abstr.) Phytopathology 107:S5.125. https://doi.org/10.1094/PHYTO-107-12-S5.125 Oral Presentation: Molnar, T.J., J.J. Lombardoni, M.F. Muehlbauer, J.A. Honig, S.A. Mehlenbacher, J.M. Capik. 2017. Progress in breeding for resistance to eastern filbert blight in the eastern United States. Abstracts of the IX International Congress on Hazelnut:17. Poster: Molnar T.J., J.A. Honig, A. Mayberry, R.S. Revord, S.T. Lovell, S.A. Mehlenbacher and J.M. Capik. Corylus americana: a valuable genetic resource for developing hazelnuts adapted to the eastern United States. Abstracts of the IX International Congress on Hazelnut: 104. Samsun, Turkey August 2017 Invited oral presentation Thomas Molnar: Essex County Master gardener meeting, title: Hazelnut: a new industry for New Jersey and Beyond. Nov. 11, 2017 Invited oral presentation Thomas Molnar: 2017 Green Expo turf & landscape, title: New dogwood and ornamental hazelnut varieties for the landscape. Borgata Hotel, Atlantic City, New Jersey, December 6, 2017. Poster: Michael Gandler, John Capik, and Thomas Molnar. 2018 Long-term Observation of Resistance Sources to Eastern Filbert Blight in New Jersey. Annual Meeting of the Northeastern branch of the American Society for Horticultural Science. Philadelphia, PA, Jan. 6, 2018 Poster: David Hlubik, Harna Patel, John Capik, James E. Simon, and Thomas J. Molnar. Analysis of Volatile Diversity in European Hazelnuts and other Corylus Species Using GC/MS Static Headspace. Annual Meeting of the Northeastern branch of the American Society for Horticultural Science. Philadelphia, PA, Jan. 6, 2018 Oral presentation: Alex Mayberry, John Capik, Emil Milan, David J. Hlubik, Michael Gandler, and Thomas Molnar. Flowering phenology and phenotypic characterization of commercially valuable traits in wild American hazelnut (Corylus americana). Annual Meeting of the Northeastern branch of the American Society for Horticultural Science. Philadelphia, PA, Jan. 6, 2018 Invited oral presentation Thomas Molnar: Central Jersey Turf and Ornamental Institute. New Rutgers Ornamental Plants and Nut trees for New Jersey Landscapes. March 1, 2018. Battleground Country Club Manalapan, NJ, March 1, 2018. Invited oral presentation Thomas Molnar: Princeton Agricultural Association Meeting. March 22, 208. Hazelnuts: a new industry for NJ and Beyond. Invited oral presentation Thomas Molnar: Hazelnuts: a new industry for NJ. Rutgers Undergraduate Food Science Club. April 2, 2018 Invited oral presentation Thomas Molnar. The Rutgers Woody Ornamentals Breeding program: exciting progress in Cornus and Corylus. The 2018 Woody Plants Conference. Swarthmore Scott Arboretum. July 20, 2018. Oral Presentation: Alex Mayberry, Josh A. Honig, John Capik, Jennifer N. Vaiciunas, Thomas J. Molnar. Determining chloroplast haplotype variation of wild American hazelnut. Annual Meeting of the American Society for Horticultural Science. Washington DC August 5 2018 Oral presentation Thomas Molnar: Eastern filbert blight: a complicated nemesis. Northern Nut Growers Association annual meeting, Le Boulchelon resort Saint-Paulin, Québec, Canada. August 5-8, 2018. Oral presentation Thomas Molnar: Update on Rutgers hazelnut breeding program and timeline for release. Northern Nut Growers Association annual meeting, Le Boulchelon resort Saint-Paulin, Québec, Canada. August 5-8, 2018 Oral presentation: Justin Lombardoni, Josh A. Honig, Jennifer Vaiciunas, Christine Kubik, John Capik, Shawn Mehlenbacher, and T.J. Molnar. Evaluation of European Hazelnut (Corylus avellana) Genetic Diversity Using a Genotyping-by-Sequencing Approach. International Hort Congress. Istanbul, Turkey, August 12-16, 2018 Poster: Pfarr, E.; J. Honig; J. Vaiciunas; C. Kubik; J. Capik; T. Molnar. (2018). Preliminary Results of a Genotyping By Sequencing Diversity Study of Big-Bracted Dogwood (Cornus spp.) Cultivars. The American Society for Horticultural Science Annual Conference; Washington, DC Poster: Pfarr, E.; J. Honig; J. Vaiciunas; C. Kubik; J. Capik; T. Molnar. (2018). Quantitative Trait Loci (QTL) Mapping Population Development in Cornus florida Using Open Pollinated Seedlings and Simple Sequence Repeat Markers. The 6th International Workshop on the Genetics of Tree-Parasite Interactions; Mount Sterling, OH (will be published extended abstract) Invited Presentation: Thomas Molnar. Breeding Powdery Mildew Resistant Dogwoods and More at Rutgers University. Southern Region International Plant Propagators Society. Oct 21-24, 2018, 2018, Chattanooga, TN. What do you plan to do during the next reporting period to accomplish the goals?We will continue to follow the systematic methods developed over the more than 4-decade history of the woody ornamental breeding program to enhance germplasm and develop and identify superior landscape plants. We will increase our use of molecular biology approaches to support understanding of genes for disease resistance, ornamental traits, and traits associated with nut production. We will bolster our student training and outreach efforts associated with the breeding programs.

Impacts
What was accomplished under these goals? 1: We continue to evaluate plants held in our breeding nurseries originally selected by Dr. Elwin Orton. We identified one interspecific hybrid Ilex selection with a very unique upright form that merits release and a U.S. plant patent application was submitted and is nearing final review. Ten other Ilex selections with very unique phenotypes have been propagated for further testing including their response to deer browse (a substantial concern with new ornamental plants). More than ten potential Cornus releases were distributed as bud wood in August to a select group of nurseries to evaluate propagation aspects of the clones and their adaptation and performance in different regions. 2: In 2017 and 2018, we made over 500 hand pollination between powdery mildew resistant Cornus florida accessions HR15P25 and others and those with a range of floral bract colors and other highly ornamental attributes. Over 2000 seeds were harvested and placed into cold stratification in October 2017. In 2018, we field planted over 1000 seedlings from crosses and open pollinated seed harvested in 2017 with a focus on dark-pink bracted hybrid dogwoods and kousa types. 2018 seed will be germinated next year. Field evaluations are yielding very interesting individual plants highlighting powdery mildew tolerance and resistance and unique phenotypes that merit clonal propagation and replicated, multi-location testing. 3: We field-planted over 2,000 seedlings from hand crosses made in 2017 at Rutgers and Oregon State University. We continue to evaluate and cull our breeding nurseries that hold over 10,000 seedlings segregating for EFB resistance as well as traits of high importance to commercial nut production. Cumulative data allowed for the selection of four genotypes in 2017 for clonal propagation through micro-propagation for much wider multi-location yield testing. Propagation of the four clones has been initiated with a commercial micro-propagation lab. Plant patent applications are in the process of being written in regard to these breeding selection identified to hold commercial merit. 4: We continue to study EFB resistance and segregation patterns in populations derived from multiple sources of resistance. Most recently, we studied the 'Gasaway' sources of resistance. In our study, we examined the EFB response of seedlings from 31 different full-sib progenies expected to segregate for the 'Gasaway' R-gene. Trees were exposed to the disease over at least 5 years and evaluated on a scale of 0 to 5 (0=resistant, 5=highly susceptible). In general, we found the number of seedlings free of EFB (class 0) to be less than expected based on prior work in Oregon, but resistant individuals were identified in each progeny, indicating the presence of heritable resistance. When disease response classes 0, 1, and 2 were combined (resistant through highly tolerant) and considered as "resistant", the expected ratio of resistant to susceptible trees was recovered, signifying that the single dominant allele alone continues to provide a predictable level of at least tolerance to current "isolates" of the fungus found in New Jersey. Modifying genes/factors appear to play a role in the final disease response of the individual seedling. We also continue to explore genetic diversity of hazelnuts. In our most recent study, currently in preparation for submission to a peer-reviewed journal, we sought to genotype accessions using single nucleotide polymorphism (SNP) markers generated through next-generation sequencing (NGS). Germplasm included in the study consisted of accessions spanning known European hazelnut diversity, including a significant subset from the Republic of Georgia, as well as accessions representing sources of resistance to eastern filbert blight (EFB). The resulting SNP markers were used to construct a STRUCTURE diagram to visualize the populations of the included accessions. Results showed that all accessions could be grouped into 3 or 9 populations depending on the parameter used for grouping. Compared to past SSR genotyping studies, there was significant restructuring of accessions across populations due to the greater number of SNP markers. This study shows the advanced capabilities of NGS and how its use of markers can be used to improve our collective knowledge of hazelnut diversity moving forward. 5: Work continues towards identification of additional genera to develop in the program, although progress has been slow since a majority of efforts continue to be placed on Cornus and Corylus where a perceived demand from the nursery and horticultural industry is currently high.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Tobia, J., M. Muehlbauer, J. Honig, J. Pscheidt, and T.J. Molnar. 2017. Cluster analysis of Anisogramma anomala isolates collected from the Pacific Northwest and New Jersey. (Abstr.) Phytopathology 107:S5.125. https://doi.org/10.1094/PHYTO-107-12-S5.125
• Type: Journal Articles Status: Published Year Published: 2017 Citation: Capik, JM, M. Muehlbauer, P. Wadl, and T.J. Molnar. 2017. Cornus kousa Rutpink (Scarlet Fire�) dogwood. HortScience. 52:14381442.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Muehlbauer, M., J.M. Capik, T.J. Molnar, and S.A. Mehlenbacher. 2018. Assessment of the Gasaway source of resistance to eastern filbert blight in New Jersey. Scientia Horticulturae 235:367-372
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Nowicki, M., S.L. Boggess, A.M. Saxton, D. Hadziabdic, Q-YJ Xiang, T. Molnar, M.L. Huff, M.E. Staton, Y. Zhao, and R. N. Trigiano. 2018. Haplotyping of Cornus florida and C. kousa chloroplasts: insights into species-level differences and patterns of plastic DNA variation in cultivars. PLoS ONE 13(10): e0205407.
• Type: Journal Articles Status: Awaiting Publication Year Published: 2018 Citation: Wadl, P.E. Mack,B.M., Beltz, S.B., Moore, G.G., Baird,R.E., Rinehart,T.A., Molnar, T.J., Staton, M.E., Hadziabdic, D., and R.N. Trigiano. 2018. Development of genomic resources for the powdery mildew, Erysiphe pulchra. Plant Disease https://doi.org/10.1094/PDIS-05-18-0719-A
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Muehlbauer, M. J. Honig, and T. Molnar. 2018. The use of chloroplast gene sequences to confirm maternal backgrounds of powdery mildew resistant interspecific hybrid dogwood (Cornus kousa x C. florida). Acta Hort 1191: 17-26 (DOI 10.17660/ActaHortic.2018.1191.3)
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Thomas J. Molnar, Josh A. Honig, Alex Mayberry, Ronald S. Revord, Sarah T. Lovell, Shawn A. Mehlenbacher, and John M. Capik. 2018.. Corylus americana: a valuable genetic resource for developing hazelnuts adapted to the eastern United States. Acta Hort 1226: 115-121 (DOI 10.17660/ActaHortic.2018.1226.11)
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Thomas J. Molnar, Justin J. Lombardoni, Megan F. Muehlbauer, Josh A. Honig, Shawn A. Mehlenbacher, and John M. Capik. 2018. Progress breeding for resistance to eastern filbert blight in the eastern United States. Acta Hort 1226: 79-85 (DOI 10.17660/ActaHortic.2018.1226.11)
• Type: Theses/Dissertations Status: Published Year Published: 2017 Citation: Muehlbauer, M.F. 2017. The use of molecular and biochemical tools to assist in the breeding of hazelnuts (Corylus spp.). Rutgers University. Ph.D. dissertation, 193 pp. https://rucore.libraries.rutgers.edu/rutgers-lib/53746/
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Molnar, T.J., A. Mayberry, D. Hlubik, J. Capik, and J. Honig. 2018. Collection and evaluation of wild American hazelnut genetic resources: building the foundation for wide expansion of hazelnut production. Pg. 38. Proceedings of the Twenty-seventh Annual Rutgers Turfgrass Symposium. Center for Turfgrass Science. School of Environmental and Biological Sciences. Rutgers University. January 12, 2018.
• Type: Other Status: Published Year Published: 2018 Citation: Mayberry, Alex, J.M. Capik., and T.J. Molnar. 2018. Corylus americana. The nutshell. Volume 72(3): 29-33
• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Capik J. and T.J. Molnar. 2017. An update on sources of resistance to eastern filbert blight disease of hazelnuts in New Jersey. HortScience 52(9):S5. (Abstr.) [Originally published in: Proc. (Vol. 2). The Northeastern Plant, Pest, and Soils Conference.Flessner, M.L, (ed.). 2017].
• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Mayberry, A., J. Capik, and T.J. Molnar. 2017. Phenotypic characterization of wild american hazelnut (Corylus americana) germplasm to support future hybrid hazelnut breeding. HortScience 52(9):S3. (Abstr.) [Originally published in: Proc. (Vol. 2). The Northeastern Plant, Pest, and Soils Conference.Flessner, M.L, (ed.). 2017].
• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Muehlbauer, M., D. Hlubik, and T.J. Molnar. 2017. Characterization of the effects of hybrid hazelnut pollenizers (Corylus americana x C. avellana) on the oil content and profiles of several European hazelnut (C. avellana) cultivars. HortScience 52(9):S6. (Abstr.) [Originally published in: Proc. (Vol. 2). The Northeastern Plant, Pest, and Soils Conference.Flessner, M.L, (ed.). 2017].
• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Hlubik. D., M. Muehlbauer, J. Capik, J. Simon., and T.J. Molnar. 2017. Effect of Pollen Parents on Oil Characteristics in European Hazelnuts. HortScience 52(9):247. (Abstr.)

Progress 10/01/16 to 09/30/17

Outputs
Target Audience:Prospective hazelnut growers and nursery operators and owners in New Jersey were reached as well as the agricultural scientific community through multiple presentations and posters provided by me and my students (graduate and undergraduate) at scientific meetings and grower tours. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Six graduate students were associated with the project (Megan Muehlbauer, Justin Lombardoni, Erin Pfarr, Alex Mayberry, Peninah Feldman and Michael Gandler) and two undergraduate students (David Hlubik and Janine Tobia). Mr. Mayberry, Mr. Hlubik, Ms. Tobia, and S. Muehlbauer presented their work at conferences over the period. Megan Muehlbauer completed her PhD in May 2017. All students are currently working on independent projects affording significant training and professional development. How have the results been disseminated to communities of interest?Results have been disseminated largely through presentations at scientific and grower meetings and field tours provided at the Rutgers reserach farms. What do you plan to do during the next reporting period to accomplish the goals?We will continue to follow the systematic methods developed over the more than 4-decade history of the woody ornamental breeding program to enhance germplasm and develop and identify superior landscape plants. We will increase our use of molecular biology approaches to support understanding of genes for disease resistance, ornamental traits, and traits associated with nut production. We will bolster our student training and outreach efforts associated with the breeding programs.

Impacts
What was accomplished under these goals? 1. We continued the evaluation of Ilex breeding selections derived from earlier breeding efforts at Rutgers. A US plant patent application was submitted for Ilex x 'CR195-115', an interspecific hybrid with a unique pyramidal growth habit. Several other Ilex breeding selections were identified for propagation and distributed to nurseries in New Jersey and Maryland for further testing. Six new Cornus (dogwood) selections were identified with superior deep-pink floral bract color, which were propagated for testing in 2017. 2. In 2017, we continued breeding efforts to obtain powdery mildew resistant Cornus florida hybrids that express a variety of floral bract colors and growth habits. Over 1,000 seedlings were germinated in the greenhouse from crosses made in 2016. Efforts are now being placed on studying inheritance of resistance and mapping the resistance loci/qtl in C. florida. 3. Efforts continue towardsdeveloping large populations of hazelnuts segregating for ornamental traits. In 2017, we planted select seedlings with highly attractive dissected leaves into field nurseries to evaluate their response to eastern filbert blight. Our best EFB-resistant purple-leaf ornamental selection was propagated for multi-location testing. 4. Efforts continue to introgress new sources of EFB-resistance into improved breeding populations for nut producing and ornamental hazelnuts. Seedling germinated in 2016 carry R-genes from accessions originating in Poland and the Republic of Georgia. In 2017, we completed a study of the molecular genetic diversity of the EF B fungus A. anomala, which in preparation for submission to a journal. A second study is nearing completion that focuses on genetic relationships of isolates of A. anomala able to overcome the 'Gasaway' gene for resistance.

Publications

• Type: Conference Papers and Presentations Status: Other Year Published: 2017 Citation: Honig, J.A., J. Vaiciunas, M. Muehlbauer, and T. Molnar. 2017. Combining field and lab data to reach new heights in the Rutgers hazelnut breeding program. Pg 17-19. Proceedings of the Twenty-sixth Annual Rutgers Turfgrass Symposium. Center for Turfgrass Science. School of Environmental and Biological Sciences. Rutgers University Jan. 13, 2017.
• Type: Other Status: Published Year Published: 2016 Citation: Molnar, T.J. and J. Capik. 2016. New Eastern Filbert Blight Resistant Hazelnuts from the Republic of Georgia. Annual Report of the Northern Nut Growers Assoc. 106:13-18
• Type: Other Status: Published Year Published: 2017 Citation: Molnar, T. and J. Capik. 2017. Hazelnut accessions from Crimea and Russia transmit resistance to eastern filbert blight. Annual Report of the Northern Nut Growers Assoc. 107:16-19
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Peninah Feldman, John Capik, and Thomas Molnar. 2016. Investigating eastern filbert blight response in hazelnut progenies from new sources of resistance. HortScience 51(9):S6 (Abstr.).
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Muehlbauer, M., A.Morgan, J. Capik, D. Hlubik, and T. Molnar. 2016. Assessment of the effect of interspecific hybrid hazelnut pollen on nut set of European hazelnut in New Jersey. HortScience 51(9):S4 (Abstr.).
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Muehlbauer, M., T. Molnar, J. Capik, D. Ward, and D. Hlubik. Pollinizers Affect Kernel Characteristics in European Hazelnuts (Corylus avellana). HortScience 51(9):S185(Abstr.).
• Type: Conference Papers and Presentations Status: Other Year Published: 2017 Citation: Molnar, T.J. 2017. Going nuts: continuing a 40-year-old woody ornamental breeding program. Combined Proceedings of the International Plant Propagators Society 67:305-312
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Capik, J., M. Muehlbauer, P. Wadl, and T.J. Molnar. 2016. Using SSR markers to confirm the parentage of the new dogwood Cornus kousa Rutpink Scarlet Fire. HortScience 51(9):S4 (Abstr.).

Progress 07/01/16 to 09/30/16

Outputs
Target Audience:Prospective hazelnut growers and nursery owners in New Jersey were reached as well as the agricultural scientific community through multiple presentations and posters provided at scientific and grower meetings and tours given at Rutgers University. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Four graduate students were associated with the project (Megan Muehlbauer, Peninah Feldman, ROb Mattera, and Clayton Leadbetter). Rob Mattera published one paper in 2015 and completed his Masters degree on a project on Cornus in May 2016; Megan and Peninah made presentations in 2016 and expect to have several research manuscripts published in 2017 on their work that constitutes chapters in their dissertations; and Clayton published one manuscript. Five undergraduae students were also trained on the project. How have the results been disseminated to communities of interest?Results have been disseminated through field tours at Rutgers and by the following presentations and posters: Oral presentation: Thomas Molnar. Ornamental hazelnuts: developing edible landscape plants as bridge to backyard nut growing. 107th Annual Meeting of the Northern Nut Growers Association. Nebraska City, Nebraska. August 2, 2016. Oral Presentation: Megan Muehlbauer*, Thomas Molnar, John Capik, Daniel Ward, and David Hlubik. Pollenizers Affect Kernel Characteristics in European Hazelnuts (Corylus avellana). Annual Conference of the American Society for Horticultural Science. Aug. 10, 2016. Oral Presentation: Thomas Molnar: The Rutgers University Woody Ornamental and Nut Tree Breeding Program: NEW Plants and Future Directions. SEGreen Plant Conference. Athens Georgia Aug. 31-Sept 1, 2-16. http://www.segreen.org/plant-conference.html What do you plan to do during the next reporting period to accomplish the goals?We will continue to follow the systematic methods developed over the more than 4-decade history of the woody ornamental breeding program to enhance germplasm and develop and identify superior landscape plants. We will increase our use of molecular biology approaches to support understanding of genes for disease resistance, ornamental traits, and traits associated with nut production. We will bolster our student training and outreach efforts associated with the breeding programs.

Impacts
What was accomplished under these goals? 1. We continue to evaluate superior, unreleased individual plants held in our breeding nurseries originally selected by Dr. Elwin Orton. We have identified one interspecific hybrid Ilex selection with a very unique upright form that merits release.A U.S. plant patent application has been written and is in the process of submission. Two other Ilex selections have been propagated for further testing. Eight potential Cornus releases were distributed as budwood in August to a select group of nurseries to evaluate propagation aspects of the clones and their adaptation and performance in different regions. 2. In 2016, we made over 300 hand pollination between powdery mildew resistant Cornus florida accessions and those with a range of floral bract colors and other highly ornamental attributes. Over 500 seeds were harvested and placed into cold stratification in October 2016. We field planted over 1,500 seedlings from crosses and open pollinated seed harvested in 2015 with a focus on dark-pink bracted hybrid dogwoods and kousa types. 3. We field-planted over 2,000 seedlings from hand crosses made in 2015 at Rutgers and Oregon State University. Of this, about 50 were cut-leaf types representing the first time we recovered this recessive ornamental trait in our breeding program. A population of over 300 purple leaf hybrid hazelnuts was reduced to only 60 trees based on ornamental value (color retention, husk display, and growth habit) with the best 10 trees identified and slated to be propagated in 2017. We continue to evaluate and successively cull our breeding nurseries that hold over 12,000 seedlings segregating for EFB resistance as well as traits of high importance to commercial nut production. Cumulative data allowed for the selection of six genotypes in 2016 for clonal propagation through micro-propagation for much wider multi-location yield testing. Propagation of the six clones has been initiated with a commercial micro-propagation lab. 4. We identified new sources of resistance from Russia and Crimea and documented inheritance. In 2003, 1,285 Russian/Crimean seedlings were planted in New Jersey and nearly all died from EFB; however, ~70 resistant trees were identified. We crossed 11 with susceptible male parents to examine inheritance of resistance. 14 progenies were field planted in 2010/11, annually exposed to high levels of A. anomala, and evaluated for EFB response in 2015. A rating scale of 0 (no signs or symptoms of EFB) to 5 (all stems containing cankers) was used. We found that all 11 accessions transmitted resistance to a useful number of their offspring. Interestingly, all progenies showed a clear bimodal distribution of resistant (rating = 0) and highly susceptible trees (rating = 4 or 5) with few intermediate individuals, which indicates genetic control by one or a small number of major genes. Further, 7 additional sources of EFB-resistance were examined for inheritance of resistance. This includes C. avellana OSU 495.072 and OSU 759.010, from Russia and the Republic of Georgia, respectively; 4 National Arbor Day Foundation hybrids related to C. americana 'Winkler'; Grimo 208P and Yoder #5 related to C. americana 'Rush'; 'Grand Traverse', which has a lineage containing Turkish tree hazel; and OSU 526.041, a hybrid of C. heterophylla. Controlled crosses were made between these resistant plants and known susceptible parents. The offspring were grown in the field and exposed to high disease pressure and then evaluated. Results from 2016 showed that all of the sources examined yielded progeny expressing a striking bimodal pattern again indicating control by a very limited number of major genes. Further, a mapping population was created by crossing the EFB resistant Russian H3R07P25 with EFB susceptible OSU 1155.009 for the purpose of creating a linkage map. In 2012, 281 plants were field planted, exposed to EFB, and evaluated. In 2016, Genotyping by Sequencing was performed on 119 seedlings and parents using a PstI-MspI ddRAD-seq procedure similar to the methods described by Elshire et al. (2011) and Poland et al. (2012). From this, 2217 SNP and SSR markers were placed on 11 linkage groups using JoinMap at a LOD score of 20. A putative major QTL for EFB resistance was identified on linkage group 2 using MapQTL. 5. Work continues towards identification of additional genera to develop in the program, although progress has been slow since a majority of efforts continue to be placed on Cornus and Corylus where a percieved demand from the nursery and horticultural inustry is currenlty high.

Publications

• Type: Journal Articles Status: Published Year Published: 2016 Citation: Leadbetter, C.W., J.M. Capik, Mehlenbacher, S.A., and T.J. Molnar. 2016. Hazelnut accessions from Russia and Crimea transmit resistance to eastern filbert blight. Journal of the American Pomological Society 70:92-109
• Type: Conference Papers and Presentations Status: Other Year Published: 2016 Citation: Molnar, T.J., J. Capik, J.A. Honig, M. Muehlbauer, and S. Mehlenbacher. 2016. Securing and expanding the U.S. hazelnut industry through breeding for resistance to eastern filbert blight. Pg 64-67. Proceedings of the Twenty-fifth Annual Rutgers Turfgrass Symposium. Center for Turfgrass Science. School of Environmental and Biological Sciences. Rutgers University
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Muehlbauer, M., T. Villani, J. Simon, H. Juliani and T. Molnar. 2016. Lipid profiles of a diverse collection of Corylus species and interspecific hybrids. Acta Hort 1109:29-33. DOI 10.17660/ActaHortic.2016.1109.5