DEVELOPMENT OF IMPROVED FRESH-MARKET MUSCADINES

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1002661
• Project Start Date: Mar 3, 2014
• Project End Date: Feb 28, 2019
• Program Code: [(N/A)]- (N/A)

Recipient Organization
UNIVERSITY OF GEORGIA
200 D.W. BROOKS DR
ATHENS,GA 30602-5016

Performing Department
Horticulture

Non Technical Summary
New muscadine varieties are needed to advance the muscadine grape industry in Georgia. These cultivars should possess a combination of favorable traits including large fruit size, self-pollinating flowers, disease resistance, dry stem scar, and edible skins. In addition, more cold-hardy fresh market types are needed to expand the muscadine production region into north Georgia. This project will develop new muscadine varieties using traditional plant breeding methods.

Animal Health Component

20%

Research Effort Categories

Basic

10%

Applied

20%

Developmental

70%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
202	1130	1081	34%
201	1130	1081	33%
204	1130	1081	33%

Knowledge Area
204 - Plant Product Quality and Utility (Preharvest); 202 - Plant Genetic Resources; 201 - Plant Genome, Genetics, and Genetic Mechanisms;

Subject Of Investigation
1130 - Table grapes;

Field Of Science
1081 - Breeding;

Keywords

muscadines

grapes

vines

viticulture

breeding

fruits

small fruits

Goals / Objectives
1: Development of fresh-market cultivars with self-fertile flowers. Our primary short-term goal is to release a series of new fresh-market cultivars to replace the currently used muscadine cultivars. The current cultivar lineup largely consists of a combination of female cultivars with a large berry size but limited yield potential and self-fertile cultivars with medium sized berries. Growers are demanding self-fertile cultivars capable of producing large sized berries (minimum of 10-11g). This demand will be met by producing a series of both bronze and black cultivars ripening throughout the harvest season. Ideally we want to have a 2 cultivars available for each In addition, we have identified a distinct Growers are enthusiastic about this new color as it represents a new market class that might generate additional sales.2: Development of improved texture in muscadine cultivars. Development of improved texture in muscadine is an important medium-term goal of the breeding program. I believe that muscadines must change from being tough-skinned and soft-fleshed to more tender-skinned with a firm, crisp flesh. In addition to easy mastication, the skin must also have neutral (non-bitter) taste. These traits will be especially important if we are able to incorporate seedlessness into muscadine as it does little good to have a seedless berry if the consumer still has to discard the skin. The development of a large-sized, seedless berry with a crisp palatable texture, in combination with the known health benefits of consuming muscadines, would create a product with excellent marketability. Germplasm for improved skin and flesh texture has been identified (Conner, 2013b), and firm berry flesh has already been incorporated into 'Lane' muscadine which was recently released (Conner, 2013a). Textural analysis skin and flesh is now routinely incorporated into our breeding program through the use of a texture analyzer.3: Development of seedless muscadine cultivars. Since there is no source of seedlessness in muscadine germplasm, we are attempting to bring seedlessness into muscadine from V. vinifera. Seedlessness is inherited as a single dominant gene, although modifiers play a role in the level of seedlessness produced in the progeny. Introgression of Euvitis traits into Muscadinia is difficult because the chromosome number of Muscadinia (2n=40) differs from Euvitis (2n=38), making hybrids largely sterile. However, a group of complex hybrids have been identified which can serve as a bridge between the two species. Our plan is to cross seedless Euvitis cultivars to these hybrids, select seedless, self-fertile progeny and cross those back to muscadine. This has been done recently by a private grape breeder and has resulted in the production of seedless muscadines. We are using the same crossing plan that was used in that work, although we are expanding the number seedless Euvitis parents used.

Project Methods
Germplasm. The University of Georgia has a large collection of potential parental materials including existing cultivars from this and other breeding programs, selections from the UGA breeding program, and several interspecific hybrids from various sources. These have all been evaluated for fruit quality and productivity over several seasons, and their pedigrees have also been examined for their degree of genetic relatedness. In designing crosses, preference is given to combinations which maximize genetic diversity and produce a favorable combination of traits.Crossing. All crossing is conducted on field-grown material. Generally female flowered vines are used as the female parent due to the difficulty of emasculated self-fertile vines. Flowers of male and female parents are bagged 2-3 days before anthesis, and hermaphroditic flowers are emascaulated at this time. Crosses are effected by removing the male parent flower cluster and brushing its anthers over the female parent stigmas. First crossing is conducted when flowers are about 25% open, and flowers are pollinated every other day for a total of 2-3 pollinations. Then the female cluster is rebagged for approximately 2 weeks after which the bag is removed and the cluster marked with flagging tape. Seeds are removed from ripe fruit, washed, and air dried. Seeds are then stratified for approximately 90 days after which they are planted in the greenhouse. When mature vines leaf out in the spring, seedlings are transplanted into the seedling vineyard. Approximately 2000 seedlings are started during each cycle.Early seedling evaluations. Seedlings are planted at a spacing of 2 feet between seedlings in the row and 15 feet between the rows. Seedlings are trained to a single wire trellis at a height of five feet. Seedlings are given optimum nutrition and irrigated by laying a drip tube along the row. No fungicides are applied to the seedling vines so that susceptibility to disease can be monitored. Each vine will be trained to one short two foot cordon and allowed to flower. Seedlings grow quite vigorously and generally some have begun to flower in the second season with most flowering in the third year. Once desirable seedlings are identified, neighboring undesirable seedlings are removed to allow the selection more room to fruit in the succeeding year. Emphasis on initial selection is based on fruit size, generally at least 9 g, and presence of hermaphroditic flowers, and vine productivity. Other factors of importance include flavor, skin thickness and palatability, non-leaking stem scars, berry Selections which are to be advanced to the mid-stage evaluations will be propagated by softwood cuttings. Seedling progenies are evaluated for 4-5 years and then removed in order cycle the vineyard for the next round of seedlings.Mid-stage seedling evaluations. Single plant selections from the early seedling evaluations are replicated into 2-vine plots at a ten foot spacing for further evaluation of vine performance and fruiting characteristics. Selections are evaluated for berry quality, vine phenology, vine productivity, and disease resistance.Advanced evaluation. Superior selections are advanced to replicated yield trials located at the Tifton-Campus and at Paulk Vineyards in Wray, Georgia. Vine vigor is calculated by measuring the caliper of the trunk 75 cm above the ground. Vine yields are estimated by harvesting fruit from 1 meter of the interior cordon and then multiplying the sample yield by the total vine length. Vines are harvested from one to four times depending upon the uniformity of the ripening with the first harvest occurring as soon as approximately one half of the berries are ripe. Once the yield is weighed to give the total yield weight the berries are then sorted. Berries with any visible sign of decay are removed and weighed to calculate percent berry rot. Of the undecayed berries, berries are sorted into those which have pedicel scar splits (large cracks in which the interior flesh is visible), pedicel scar tears (peeling back of the berry epidermis), and dry pedicel scars. Percentage of each of these categories is calculated by dividing the weight of each category by the total weight of all three categories and then multiplying by 100. Rotted berries and berries with pedicel scar split are commonly removed prior to packing fruit, so usable yield is calculated by the formula (total yield) × (1 - % berry rot) × (1 - % pedicel scar split). Ten berries are then randomly selected from the usable yield sample and measured for berry weight and diameter. All ten berries are then crushed together to provide juice to determine percent soluble solids. Additional observational trials of advanced selections take place at the Hort Farm in Watkinsville, GA, and at North Carolina State University, University of Arkansas, and Auburn University. Advanced selections which perform better than standard cultivars in the yield trials and which exhibit no unacceptable defects are submitted for release with patent protection from the University of Georgia.

Progress 03/03/14 to 02/28/19

Outputs
Target Audience:Muscadine growers. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?3 presentations to scientific meetings, 5 meetings to state or regional muscadine grower meetings. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Objective 1: Development of fresh-market cultivars with hermaphroditic flowers. In 2019 we made 16 muscadine crosses generating about 1,700 seed. Most crosses were designed to produce progenies with crisp skin and firm pulp with an improved vine vigor. Other crosses were to late harvest selections to extend the harvest season into mid-September. A few crosses were also made to various Muscadinia × Euvitis hybrids to incorporate the cut-leaf pattern for potential ornamental homeowner use. 1,148 seedlings were planted out from the 2018 crosses into the seedling vineyard. We evaluated about 3,400 seedlings from the 2015-2017 years crosses and made 22 selections. A new replicated trial was begun in 2017 at the station vineyards. Yield and quality analysis of these selections was begun in August of 2019. In the spring of 2018 this trial was expanded by planting an additional UGA selection, and three University of Arkansas selections. In the spring of 2019 this trial was replicated at Paulk Vineyards and at the University of Florida where the new viticulturist will trial our new selections. This new trial has a focus of trialing hermaphroditic cultivars with a 15 g berry size and new late season selections. The industry greatly desires to have a new cultivars ripening through the month of September to extend their harvest window. In the spring of 2020 Auburn University has asked for four selections to be trialed in a new cultivar trial in Alabama. In the summer of 2018 'RubyCrisp' (Ga. 8-1-338) was approved for release. 'RubyCrisp' is a large hermaphroditic red-colored cultivar. This new color has generated a large amount of grower interest. In addition, it has a mild flavor, crisp skin, and firm flesh texture, and a 15 g berry. This selection was released as a home garden/pick your own cultivar. The thin skin often results in some berry split, which limits it use the commercial packing industry, although a North Carolina grower is attempting to cluster pick this selection to avoid this issue. Nevertheless, Ison's Nursery has indicated to us that the home-garden grower is their largest sales market and the novel color and texture of this release should ensure strong gardener interest. Objective 2: Development of improved texture in muscadine cultivars. Newer selections from our breeding program such as 'RubyCrisp' are now approaching the texture of V. vinifera table grapes. In the new yield trial Ga. 10-1-222 and Ga. 10-1-329 have firm flesh combined with extremely crisp skin and represent a textural improvement over 'RubyCrisp'. ?Objective 3: Development of seedless muscadine cultivars. Four hybrids, NC74049-10, DRX 60-40, NC 74, and Fennell's 3-way Hybrid have been identified which are partially fertile with Euvitis. Development of seedless muscadine hybrids was begun by crossing with five advanced selections of seedless V. vinifera which were provided by Dr. David Ramming of the USDA in 2011. Since that time we have used multiple sources of seedlessness from commercial vinifera cultivars, and selections and releases from Dr. John Clark's bunch grape breeding program in Arkansas. Seed from these crosses germinates well, but often has poor vigor and survivability in south Georgia. Despite this, we now have numerous seedless selections from these crosses that we are using as male parents to backcross to pure muscadine female selections. This first backcross generation has extremely poor seed set and germination. In each year since 2017 we crossed back to many diverse muscadine genotypes as well as to Fennell's 3-way Hybrid. Moderate seed set was obtained with Fennell's 3-way Hybrid and these were germinated in 2018 and evaluated with DNA markers for the presence of the seedlessness allele (Conner 2018). From these two selections were found with the seedless allele which have survived. These selections are expected to bloom in spring of 2020 and will be used to backcross to muscadine to improve fertility and incorporate seedlessness.

Publications

• Type: Journal Articles Status: Published Year Published: 2019 Citation: Lewter, J., M. Worthington, J. Clark, A. Varanasi, L. Nelson, C. Owens, P. Conner and G. Gunawan. 2019. High-density linkage maps for berry color and flower sex in muscadine grape (Vitis rotundifolia). Theor. App. Genet. 132:1571-1585.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Hickey, C., E. Smith, S. Cao, and P. Conner. 2019. Muscadine (Vitis rotundifolia Michx., syn. Muscadinia rotundifolia (Michx.) Small): The resilient, native grape of the Southeastern U.S. Agriculture 9(6):131.
• Type: Websites Status: Published Year Published: 2019 Citation: https://muscadines.caes.uga.edu/
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Cao, S. and P. Conner. 2019. Genetic diversity of muscadine grapes (Vitis rotundifolia) using SSR markers. HortScience 54(9):S245.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Conner, P. 2019. RubyCrisp, a new home-garden muscadine grape with hermaphroditic flowers and large red berries. HortScience 54(9):S189.
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Cao, S. and P. Conner. 2018. Development of simple sequence repeat DNA markers for muscadine grape cultivar identification. HortScience 53(9):S73.

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

Outputs
Target Audience:Muscadine growers. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Jan 13, 2018. Souteaster Fruit and Vegetable Growers Conference, presented talk 'Paulk Muscadine.' April 26, 2018. Tifton Turfgrass Conference, presented talk 'Muscadine breeding: Out of the swamp and onto your table.' Aug. 14, 2018. North Carolina Muscadine Field Day, presented talk 'Selection of fresh market muscadine cultivars'. What do you plan to do during the next reporting period to accomplish the goals?We will continue the program as in year's past. Likely will host field day at the Tifton Campus.

Impacts
What was accomplished under these goals? Objective 1: Development of fresh-market cultivars with hermaphroditic flowers. In 2018 we made 11 muscadine crosses generating about 1,500 seed. Most crosses were designed to produce progenies with crisp skin and firm pulp with an improved vine vigor. Other crosses were to a wild accession of V. popenoei to incorporate early bloom season and disease resistance. A few crosses were also made to various Muscadinia × Euvitis hybrids to incorporate novel taste and aroma characteristics and more upright shoot growth. 1,300 seedlings were planted out from the 2017 crosses into the seedling vineyard. We evaluated about 2,800 seedlings from the 2013-2015 years crosses and made 20 selections. A new replicated trial was begun in 2017 at the station vineyards. In the second year vines were trained to fill in the trellis space and we will begin to conduct yield trials in 2019 in the third year of growth. In the spring of 2018 this trial was expanded by planting an additional UGA selection, and three University of Arkansas selections. In the spring of 2019 this trial will be replicated at Paulk Vineyards and at the University of Florida where the new viticulturist will trial our new selections. This new trial has a focus of trialing hermaphroditic cultivars with a 15 g berry size and new late season selections. The industry greatly desires to have a new cultivars ripening through the month of September to extend their harvest window. In the summer of 2018 Ga. 8-1-338 was approved for release. Ga. 8-1-338 is a large hermaphroditic red-colored cultivar. This new color has generated a large amount of grower interest. In addition, it has a mild flavor, crisp skin, and firm flesh texture, and a 15 g berry. This selection was released as a home garden/pick your own cultivar. The thin skin often results in some berry split, which limits it use the commercial packing industry, although a North Carolina grower is attempting to cluster pick this selection to avoid this issue. Nevertheless, Ison's Nursery has indicated to us that the home garden grower is their largest sales market and the novel color and texture of this release should ensure strong gardener interest. Objective 2: Development of improved texture in muscadine cultivars. Newer selections from our breeding program such as Ga. 8-1-338 are now approaching the texture of V. vinifera table grapes. In the new yield trial Ga. 10-1-222 and Ga. 10-1-329 have firm flesh combined with extremely crisp skin and represent improvement over Ga. 8-1-338. Objective 3: Development of seedless muscadine cultivars. Four hybrids, NC74049-10, DRX 60-40, NC 74, and Fennell's 3-way Hybrid have been identified which are partially fertile with Euvitis. Development of seedless muscadine hybrids was begun by crossing with five advanced selections of seedless V. vinifera which were provided by Dr. David Ramming of the USDA in 2011. Since that time we have used multiple sources of seedlessness from commercial vinifera cultivars, and selections and releases from Dr. John Clark's bunch grape breeding program in Arkansas. Seed from these crosses germinates well, but often has poor vigor and survivability in south Georgia. Despite this, we now have numerous seedless selections from these crosses that we are using as male parents to backcross to pure muscadine female selections. This first backcross generation has extremely poor seed set and germination. In 2017 we crossed back to many diverse muscadine genotypes as well as to Fennell's 3-way Hybrid. Moderate seed set was obtained with Fennell's 3-way Hybrid and these were germinated in 2018 and evaluated with DNA markers for the presence of the seedlessness allele (Conner,2018). From these 5 selections were found with the seedless allele. These selections will be used to backross to muscadine to improve fertility and incorporate seedlessness.

Publications

• Type: Journal Articles Status: Published Year Published: 2018 Citation: Conner, P., G. Gunawan, and J. Clark. 2018. Characterization of the p3-VvAGL11 marker for stenospermocarpic seedlessness in Euvitis x Muscadinia grape hybrid progenies. J. Amer. Soc. Hort. Sci. 143:167-172
• Type: Journal Articles Status: Published Year Published: 2017 Citation: Conner, P. 2017. Paulk, a muscadine grape with hermaphroditic flowers and large berries. HortScience. 52:1639-1641.
• Type: Journal Articles Status: Published Year Published: 2017 Citation: Conner, P., J. Conner, P. Catotti, J. Lewter, J. Clark, and L. Biasi. 2017. Development and characterization of molecular markers associated with female plants in muscadine grape. J. Amer. Soc. Hort. Sci. 142:143-150.

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

Outputs
Target Audience:Muscadine growers and scientists. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Muscadine Grape Breeding: (Launched in 2006 and updated annually). Perkins-Veazie, P., G. Ma, P. Conner, J. Clark, J. Ballington. 2016. Stable Pigments For Muscadine: What Components Will Slow Wine And Juice Browning? South. Reg. Amer. Soc. Hort. Sci. Ann. Conf. Feb. 7., San Antonio, Tex. 8/16/2016 Ga. Musc. Grw. Assoc. Fall Field Day Program Chair Conner, P., P. Catotti, J. Conner, J. Lewter, and J. Clark. 2016. Development and characterization of a molecular marker associated with female flowers in muscadine grape (Vitis rotundifolia). HortScience 51(9):S217. What do you plan to do during the next reporting period to accomplish the goals?Carry on as outlined in proposal.

Impacts
What was accomplished under these goals? Objective 1: Development of fresh-market cultivars with hermaphroditic flowers. In 2017 we made 36 muscadine crosses and generated over 3,500 seed. Most crosses were designed to produce progenies with crisp skin and firm pulp with an improved vine vigor. Other crossing goals were late harvest date, cut-leaf pattern, and increasing variability. Over 1,100 muscadine seedlings were planted out from last year's crosses. We evaluated about 3,000 fruiting seedlings and made several selections. In the spring of 2017 we started a new replicated yield trial at Tifton, this trial will be expanded 2018 and will be replicated at Paulk Vineyards. From the previous trial, Ga 6-2-26 was released in the spring of 2017 as 'Paulk' muscadine. This new cultivar is the first perfect flowered muscadine with a berry size equal to the very large female cultivars (≈15 grams). Three nurseries are licensed to carry this cultivar and a verified row of vines at Paulk Vineyards is serving as a source of cuttings so that plants will be available in the spring of 2018. Also in the previous trial was Ga. 8-1-338. Ga. 8-1-338 is a large hermaphroditic red colored cultivar. The color has generated a large amount of grower interest. In addition, it has a mild flavor, crisp skin, and firm flesh texture. This selection will likely be released next year as a home garden/pick your own cultivar. The thin skin often results in some berry split, which limits it use the commercial packing industry, although a North Carolina grower is attempting to cluster pick this selection to avoid this issue. Objective 2: Development of improved texture in muscadine cultivars. Newer selections from our breeding program such as Ga. 8-1-338 are now approaching the texture of V. vinifera table grapes. In the new yield trial Ga. 10-1-222 and Ga. 10-1-329 have firm flesh combined with extremely crisp skin and represent improvement over Ga. 8-1-338. Objective 3: Development of seedless muscadine cultivars. Four hybrids, NC74049-10, DRX 60-40, NC 74, and Fennell's 3-way Hybrid have been identified which are fertile with Euvitis. Development of seedless muscadine hybrids was begun by crossing with five advanced selections of seedless V. vinifera which were provided by Dr. David Ramming of the USDA in 2011. Since that time we have used multiple sources of seedlessness from commercial vinifera cultivars, and selections and releases from Dr. John Clark's bunch grape breeding program in Arkansas. Seed from these crosses germinates well, but often has poor vigor and survivability in south Georgia. Despite this, we now have numerous seedless selections from these crosses that we are using as male parents to backcross to pure muscadine female selections. This first backcross generation generally has poor seed set and germination. In 2017 we crossed back to many diverse muscadine genotypes as well as to Fennell's 3-way Hybrid. Moderate seed set was obtained with Fennell's 3-way Hybrid and these seed will be germinated in 2018 and evaluated with DNA markers for the presence of the seedlessness allele. ?Objective 4: Development of PD resistant bunch grape cultivars. In 2017 we made 24 crosses with the goal of producing a PD resistant seedless bunch grape. Seedless parents included seedless V. vinifera table grape cultivars from the Univ. of Ark. breeding program and the USDA breeding program. Also used as male parents were the seedless Euvitis-Muscadinia hybrids from Objective 3. These were crossed onto Conquistador, Mortensen, Q21-8-17, and Z89-9-3 seeded PD-resistant bunch grapes. Over 1,500 seed were obtained from these crosses. These seedlings will germinated in the spring of 2018, evaluated for the seedlessness allele using DNA markers, and planted in the field to evaluated berry quality and PD susceptibility.

Publications

• Type: Journal Articles Status: Published Year Published: 2016 Citation: Brown, K., C. Sims, A. Odabasi, L. Bartoshuk, P. Conner, and D. Gray. 2016. Acceptability of Fresh-Market Muscadine Grapes and Attributes Related to Consumer Liking. J. Food Sci. 81:2808-2816.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Biasi, L., and P. Conner. 2016. Reproductive traits of hermaphroditic muscadine cultivars. HortScience 51:255-261.

Progress 10/01/15 to 09/30/16

Outputs
Target Audience:Muscadine growers and nurserymen in the Georgia, South Carolina, and North Carolina. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?The annual muscadine field day was held in Tifton, GA in August where growers sampled the newest selections and heard a presentation on the latest results from the breeding program. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Fourteen new breeding program selections were made with improved skin texture. Seedless hybrids were backcrossed to pure muscadine parents generating over 100 seed.

Publications

• Type: Journal Articles Status: Published Year Published: 2016 Citation: Biasi, L., and P. Conner. 2016. Reproductive traits of hermaphroditic muscadine cultivars. HortScience 51:255-261.
• Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Conner, P., P. Catotti, J. Conner, J. Lewter, and J. Clark. 2016. Development and characterization of a molecular marker associated with female flowers in muscadine grape (Vitis rotundifolia). Amer. Soc. Hort. Sci. Ann. Meeting, Atlanta Ga. Aug. 8-11.

Progress 10/01/14 to 09/30/15

Outputs
Target Audience: Nothing Reported Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Annual field days were held on the Tifton Campus which were attended by the muscadine growers from Georgia, South Carolina, and North Carolina. How have the results been disseminated to communities of interest?Through published journal articles, presentations to scientific conferences, presenations at grower conferences, and at field days. What do you plan to do during the next reporting period to accomplish the goals?The breeding program will continue with new crosses and evaluation of older material.

Impacts
What was accomplished under these goals? Objective 1: Development of fresh-market cultivars with self-fertile flowers. In 2015 we made 18 muscadine crosses and generated over 2,000 seed. Many crosses were designed to produce progenies with crisp skin and firm pulp. Other crossing goals were large size combined with perfect flowers, crisp flesh, vigorous vines, and red berry color. Over 2,500 pure muscadine seedlings were planted out from last year's crosses. We evaluated about 2,500 fruiting seedlings and made several selections. We have continued the testing of advanced selections planted in 2010 for possible release. The three selections with the most promise are Ga. 8-1-12, Ga. 8-1-338 and Ga. 6-2-26 (Table 1). Ga. 6-2-26 is a mid-season purple with self-fertile flowers. It has very large size for a self-fertile cultivar and could compete with 'Supreme', the current standard purple cultivar which has female flowers. There are currently no self-fertile cultivars with size comparable to 'Supreme', so this selection represents a breakthrough in size for self-fertile muscadine cultivars. Grower testers in Georgia and North Carolina are strongly interested in the release of this selection. We will release this selection as soon as we have stock plants available to take cuttings from. We have a row of 6-2-26 established at Paulk Vineyards planted in the fall of 2013. This row will serve as the source plants for this release and we will evaluate those plants next summer for trueness to type and release 6-2-26 in the winter of 2016/2017 with this row serving as the source plants. Ga. 8-1-12 is an early-mid season bronze cultivar with large berry size and perfect flowers. Flesh is very firm and skin is crisp. This selection is targeted as a potential new main season bronze cultivar. Ga. 8-1-338 is a large self-fertile red colored cultivar. The color has generated a large amount of grower interest. In addition, it has a mild flavor, crisp skin, and nice flesh texture. This selection will likely be released in the future as a home garden/pick your own cultivar. The thin skin often results in some berry split, which limits it use the commercial packing industry. Objective 2: Development of improved texture in muscadine cultivars. Newer selections from our breeding program such as Ga. 8-1-338 are now approaching the texture of V. vinifera table grapes. We will be planting a new trial in the summer of 2016 which incorporates three new selections with crisp skin and firm flesh. In addition many of the 2015 crosses have incorporated selections with these traits. Objective 3: Development of seedless muscadine cultivars. Four hybrids, NC74049-10, DRX 60-40, NC 74, and Fennell's 3-way Hybrid have been identified which are fertile with Euvitis. Development of seedless muscadine hybrids was begun by crossing with five advanced selections of seedless V. vinifera which were provided by Dr. David Ramming of the USDA. Seed obtained from these crosses was fertile and germinated well, and over 500 seedlings were obtained. Each year we have built on this work by using additional seedless selections and cultivars from other breeding programs. In 2015 we used the cultivars Jupiter, Sweet Scarlett, and Concord Seedless as sources of seedlessness. 'Sweet Scarlett' is notable in that it has a muscat flavor profile which does not exist in muscadine germplasm. 'Concord Seedless' has a notable labrusca flavor and ripens very early, a full month ahead of the earliest muscadines. Both of these traits would bring much needed variability to muscadine germplasm base. We have found a few seedlings with self-fertile flowers, seedless berries, and good vigor from the first crosses to V. vinifera. These selections were used as male parents to cross to female muscadines in 2015 for the first backcross generation.

Publications

• Type: Journal Articles Status: Published Year Published: 2014 Citation: Conner, P. 2014. Hall: An Early Season Self-fertile Bronze Muscadine Grape. HortScience 49:688-690.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Conner, P. 2015. Performance of eight muscadine cultivars and selections in south Georgia. Hortscience 50(9):S341
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Catotti, P. and P. Conner. 2015. Validation of a molecular marker for seedlessness in muscadine grapes. Hortscience 50(9):S326.

Progress 03/03/14 to 09/30/14

Outputs
Target Audience:We reached muscadine growers in North Carolina, Georgia, South Carolina and Arkansas with various presentations in this period. The website was available to growers throughout the world. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Brown, K., C. Sims, P. Conner, D. Gray, and A. Odabisi. Quality attributes to the consumer acceptability of muscadine grape cultivars. Ann. Inst. Food Tech. June, 22. New Orleans, La. 8/21/2015 Ga. Musc. Grw. Assoc. Fall Field Day 9/11/2014 Univ. Ark. Muscadine Field Day Advances in muscadine breeding efforts at the university of Georgia. 1/10/2015 Ga. Fruit & Veg. Grw. Assoc. Ann. Conv. New UGA muscadine cultivar releases. What do you plan to do during the next reporting period to accomplish the goals?We will continue the breeding program as outlined in the initial project description.

Impacts
What was accomplished under these goals? In the past two years we have put effort into designing a protocol to measure texture of muscadine berries using a texture analyzer. The chosen protocol measures berry puncture work and flesh maximum force. A low berry puncture work corresponds to a berry that is firm, but easily broken down during mastication. Berry flesh firmness is tested by removing a small section of skin and recording the force needed for a 5 mm cylinder to penetrate the exposed flesh.'Sugraone' and 'Midnight Beauty' are two V. vinifera table grapes with crisp flesh included for comparison. 'Blue Lake' is a V. labrusca cultivar with soft flesh. From the graph it is apparent the wide range of skin and flesh texture available in muscadine germplasm. Newer selections from our breeding program such as Ga. 8-1-338 are now approaching the texture of V. vinifera table grapes. Currently we are working with the University of Florida to conduct taste panels of muscadines with a wide range of texture attributes to delineate the traits most important to the consumer. This project is in its second year and will be completed by January. Four hybrids, NC74049-10, DRX 60-40, NC 74, and Fennell's 3-way Hybrid have been identified which are fertile with Euvitis. Development of seedless muscadine hybrids was begun by crossing with five advanced selections of seedless V. vinifera which were provided by Dr. David Ramming of the USDA. Seed obtained from these crosses was fertile and germinated well, and over 500 seedlings were obtained. We began scoring for seedlessness of this generation this year. One seedling was found with self-fertile flowers, seedless berries, and good vigor. This selection will be used as a male parent to cross to female muscadines next spring. In addition was have obtained pollen for Dr. John Clark at the Univ. of Ark. from this seedless table grape breeding program. Using this and other pollen as parent we made seven crosses to hybrids and produced over 500 seed. These grapes were bred to be grown in wetter conditions than V. vinifera tolerates and will hopefully improve the disease resistance of our hybrids which have not grown well in the field. We have also crossed to 'Rubired', a V. vinifera cultivar with red pigmented flesh. We hope to use this trait to improve the juice color of red muscadine cultivars

Publications