Brief Summary of Minutes of Annual Meeting

Brief summary of minutes of annual meeting:

Attendees at the January 2016 annual NE1231 meeting were Kathy Haynes (USDA-ARS; our host), Mark Clough (NC State), Lincoln Zotarelli (U-FL), Susan Brown (Cornell U), Walter De Jong (Cornell U), Ramon Arancibia (V. Tech), Greg Porter (U ME), Mike Peck (PA State), Xinshun Qu (PA State), Matt Kleinhenz (OH State).

Minutes from the last meeting were approved.  Site selection for the 2017 meeting was discussed.  The committee agreed that Beltsville, MD is a good meeting location for the group, Kathy Haynes agreed to host, and January 10-11, 2017 were chosen for the meeting dates.  A resolutions committee consisting of Mark Clough, Matt Kleinhenz, and Lincoln Zotarelli was appointed.  Local arrangements details were covered.

The administrative advisor report was provided by Susan Brown.  The main points were:1) this project will term 9/30/2017.  We will need to submit a request to rewrite before Feb 5, 2016; 2) NE1231 does not have an obvious impact statement in NIMSS.  It would be good to remedy this before the rewrite.  In the rewrite: explain how regional projects (NE, NC, NW, S) interact.

Ann Marie Thro was not able to attend so there was no USDA_NIFA report.   

State and provincial reports were given describing production status, promising clones, and market needs.

• FL reported 30,500 acres with the bulk centered in the Hastings area (20,000 acres), but significant production also occurs in the panhandle (2500 acres), south (6000 acres), and central (2000 acres) regions. Most of the utilization is for chips (80%), while fresh market makes up 20%.     They had good rainfall distribution, average yields of 240 cwt/A, and low specific gravity.

• ME reported 52,000 acres (50% fry, 10% chip, 40% fresh and seed. Yields were excellent this year and the weather was very cooperative (cool, enough rain for most of bulking period).  A dry period during bulking led to some stem end issues.  Commercial potatoes had late blight only in south in areas of mixed vegetable production (the University of Maine late blight trial in northern ME had no blight. The industry has experienced a flare-up of black leg this year and this has impacted areas that receive ME seed.  Some has been reported to be caused by Dickeya dianthicola, while some was reportedly Pectobacterium   D. solani has not been detected.  Maine is reworking regulations in light of blackleg issues, to make seed certification more strict.

• NY grew 16,500 acres (50% chip, 45% table, 5% seed). The industry had exceptionally high specific gravity in 2016 with concomitant blackspot bruise problems.

• NC reported 70% chip production and 30% table (mostly reds, esp Dark Red Norland). Low specific gravities and considerable soft rot was seen at harvest.  About one third of NC potato acreage is managed by Black Gold.  The ideal red for NC would have earliness of DR Norland, yield of Chieftain and color of Strawberry Paw.  DR Norland does not skin much in NC, while Dakota Jewel and Strawberry Paw both do.

• OH had 3000 acres, all tablestock. There were no known blackleg problems in 2015.  Flooding rains occurred in June.  Yields and specific gravity were both very high.  Potato traits that appeal to the typical small-scale OH mixed vegetable grower would include unique marketing attributes.  There are many family-owned grocers with ten or fewer stores.

• PA grew 6500 acres comprised of 70% for chipping and 30% for table. There are a few large chip growers and many small table growers.  Those who planted early had a good crop, those who planted late did not fare so well (washouts, rot in field).

• VA reported 5000 acres (25% chip, 75% table). Superior and Envol are used for table (earliness is a key trait).  Atlantic and Snowden are the primary varieties for chipping.

There were no industry representatives in attendance at the meeting.   

Kathy Haynes provided a research presentation describing a project aimed at developing a deep orange (high zeazanthin) 4x variety.  Knowing the genes involved (deep orange requires dominant allele of beta carotene hydroxylase, four copies of recessive allele of zeazanthin epoxidase), she had assumed this would be a straightforward project, but it hasn’t been a successful project to date.  The  offspring tend to be unthrifty.  Kathy is also working to develop a Papa Criolla type with longer tuber dormancy.  Ideally this variety type has thin skin, lenticels that are not prominent, a boiled product that falls apart, a fried product is mealy (texture of wet sand), and long dormancy.

Plant Pathology and breeding program reports were presented by participants. 

• Greg Porter shared some slides from J. Hao (University of Maine Plant Pathologist). Pink rot is a common problem in Maine, as soil types there are often wet in the root zone.  The natural path of infection: zoospores infect stolons and roots then move to tubers from there.  Note that this differs from typical lab screen, where tubers are inoculated directly.  High zoospore numbers are needed for cut tuber assays, as spores don’t germinate at low spore concentration.  Approximately 70% of pink rot strains collected from problem storages in Maine are resistant to mefenoxam.  Hao measures resistance in field, monitoring reductions in stand and incidence/severity of rot at harvest.  Atlantic and Snowden are both relatively tolerant to pink rot.

• Greg Porter also handed out results of common scab testing in Maine.

• Xinshun Qu will email results of common and powdery scab testing from PA, as well as late blight resistance trial results.

Breeding program reports were presented.

• ME grew ~50,000 first-year seedlings (35K from Maine, 15K from elsewhere) with about 2% saved at the single-hill stage.  The program effort is ~50% russets (crossing in Presque Isle), 10% specialty, 40% chip, whites and yellows (crossing done in Orono).  Late blight, scab and PVY are priorities for resistance breeding.  Sebec was released in 2014.  It chips well in the South, but gravity is typically 2-4 points less than Atlantic.  Easton was also released in 2014.  The fry industry still evaluating it.  Caribou Russet was released in 2015.  It makes excellent fries from out of field and short storage, while it also works as a fresh market russet.  It has problems with heat necrosis where that defect is a problem.  AF4648-2 is dual-purpose, round table/chip clone with resistance to scab, PVY and golden nematode.  AF4157-6 is an early-maturity chip clone. AF4138-8 is a white table clone with resistance to common scab.

• New York grew ~18,000 seedlings and saved about 12% of chipping clones and 6% of table clones at the four-hill stage (NY does not employ a single-hill stage). Program emphasis is 70% chip and 30% fresh.  Golden nematode, scab and PVY are priorities for resistance breeding.

• North Carolina grew ~22,000 seedlings and saved 2.6% at single-hill stage. The NC program is 50% chip and 50% table (mostly reds).

• USDA-ARS. With continuing budget cuts, the program is doing less-with-less.  Program effort is 50% chips amd 50% specialty types (e.g. orange-fleshed diploid varieties and other novelty types).  Disease resistances of emphasis: common scab, late blight, PVY.

The NE1231 seed nursery shopping list was distributed and each clone was discussed.   No major changes were suggested for 2016.

Breeder’s choice selections for 2016 (all sites must evaluate these):

AF4648-2 (see above)

AF4985-1 (a red)

AF5040-8 (chips, higher gravity than Atlantic)

NY154 (chips)

NY157 (chips)

B3005-7 (chips)

BNC364-1 (chip and possible table)

Standard varieties to include in all NE1231 trials so K. Haynes can analyze G x E:

          Atlantic

Dark Red Norland

Snowden

Superior

Yukon Gold

Mark Clough provided an update on the project website: the process of including data is working well on his end and the database is growing.  People are welcomed to provide input on improvements.  Reports can be posted on the web site. 

After lengthy discussion, decided that in future years, all evaluators would include a merit score for each clone tested.  Where:

        1 = outstanding

        2 = good

        3 = so-so

        4 = not acceptable

Each evaluator is to integrate all the trial data they collect for each clone each year, along with their knowledge of the local potato industry, to arrive at the merit scores.

Greg Porter provided an update on the Eastern USDA-NIFA Special Grant for Potato Breeding Research.  Funding was obtained from the 2015 RFA and subcontracts should now be in place.  Appreciation was expressed to everyone for getting grant material in on time.  Our grant continues to receive positive reviews as an applied breeding project, but we need to be looking at funding opportunities to expand research beyond our current framework.  Note that our current special grant includes an expanded extension component – please reflect this in progress reports.  The next potato special grant RFP will likely come out in Spring 2016. 

Project Accomplishments:

This multidisciplinary, regional project utilizes existing strengths and resources of the potato breeding community in the eastern US, and it encourages the pooling of regional resources and promotes increased communication within the potato community located in the northeast, mid-Atlantic and southeast. The overarching goal of this specific project is to identify new potato varieties for use in the Northeastern, mid-Atlantic and southeast US, which will contribute to a more sustainable and profitable potato industry. Most major varieties, including Atlantic (the dominant out-of-field chipping variety in the US) as well as three recent chip potato varieties that have resistance to internal heat necrosis, Harley Blackwell, Elkton and Sebec are products of the coordinated eastern potato breeding and variety development effort. As such, the NE-1231 Project (and its predecessors NE-1031, NE-1014, NE-184 and NE-107) have played a central role in eastern potato variety development for many years. 

This regional project has: 1) allowed potato breeders to share breeding materials and test results; 2) along with the USDA NRSP6 Potato Germplasm Enhancement Project it has facilitated potato germplasm selection and evaluation under diverse environmental conditions by all the breeding programs in the eastern US; 3) given research and extension personnel the opportunity to evaluate new selections from several potato breeding programs; 4) facilitated regional germplasm screening for specific characteristics at a single location (e.g. early blight and powdery scab resistance in PA; scab resistance in ME); 5) developed variety profiles and cultural recommendations for each selection put into commercial production; and 6) as noted above, resulted in the release and adoption of most, if not all, of the major potato cultivars currently produced in the eastern US.

Potato breeding for improved quality and pest resistance was conducted in ME, NY, NC, and USDA-ARS Beltsville, MD during 2015. These four programs focus on specific pest and marketing issues, so that regional resources are used efficiently.  For example, ME is the only breeding program in the region which focuses on russets and long whites for processing (50% russets, 40% fresh and chipping whites, 10% specialty).  ME also emphasizes research on late blight, pink rot, potato virus Y, and scab resistance.   During 2015, our programs generated 673 new tetraploid families (622,000 seeds) from crosses using parents with desirable quality, utilization, adaptation, and/or pest resistance traits. USDA-ARS also generated 36 2x crosses (231,000 seeds) for use in germplasm improvement.  Progeny (109,110) from earlier crosses were field selected resulting in 4169 clones that will be further selected under conditions with diverse abiotic and biotic stress in the eastern U.S. and beyond.

Advanced clones from our project were introduced to growers through field days, presentations, publications, web sites, and direct contact with stakeholders.  Seven advanced clones were entered into tissue culture programs leading to commercial seed production. Several advanced clones and newly released varieties are currently being evaluated in commercial scale trials on-farm for their potential across the US.  The most promising chipstock lines currently under evaluation include: Beacon Chipper, Elkton, Lamoka, Waneta, Sebec, AF4157-6, BNC182-5, NC0349-3, NY148, and NY154.  AF4138-8, AF4648-2, NY150 and are being evaluated for the round-white fresh market. NY150 is a specialty white with very small, bright tubers.  The most promising red-skinned tablestock clones are: Little Ruby (B2152-17), Red Maria (NY129), Strawberry Paw (NY136), and AF4985-1. AF4659-12, is a pinto-type, yellow-fleshed ‘roasting’ variety that is being evaluated by small-scale local foods markets. 

Each eastern breeding program submits its most promising advanced clones to the regional project’s seed nursery in ME.  During 2015, the project distributed seed potatoes for 12 regional potato variety trials conducted in six states and two Canadian provinces.  Eleven standard varieties and 26 experimental clones were tested for yield, tuber quality, and pest resistance.  NE1231 Regional potato variety trials were conducted at three ME locations during 2015.  The regional trial sites (numbers of clones tested) were: Presque Isle (32), St Agatha (30), and Exeter (14).   NE1231 variety trials were also conducted in FL, NC, NY, VA, PA, OH, and Canada (NB, QC).  Each regional trial site reports results to their local stakeholders and submits their data to the project website coordinator located in NC.  The data are entered into a searchable database so that results are accessible to stakeholders and researchers anywhere in the world. Based on 2015 Maine results, Sebec (AF0338-17), AF4157-6, AF4648-2, and NY154 were the most outstanding chipping prospects.  Sebec (AF0338-17), AF4138-8, and AF4648-2 were promising round-white fresh market clones. NY150, AF4985-1, and AF4659-12 were promising specialty or red-skinned varieties. Caribou Russet (AF3362-1) Easton (AF3001-6), Teton Russet, AF4124-7, AF4172-2, and AF4296-3 were the top performing russeted clones.

Our project web site and interactive searchable database, which is updated regularly, (see: http://potatoes.ncsu.edu/NE.html) continues to grow in importance and popularity.  Evidence of its importance is the fact that it has been used as a model for other regional and national projects (e.g.  the new USDA-NIFA SCRI potato acrylamide mitigation project and the USPB national chip trials). The web site provides current contact information for project cooperators and recent research reports, as well as access to our regional variety database and a dynamic summary generator for all released varieties. The interactive database has become popular as a tool used by researchers and stakeholders, and it can be viewed at < http://potatoes.ncsu.edu/nesrch.php>.  The summary generator allows users to build a cultivar summary that contains the most up-to-date performance data in a concise one-page format <http://potatoes.ncsu.edu/nesummary.php>.

New varieties and descriptions.

This project seeks, through activities coordinated across many Northeastern states, to develop potato varieties with improved agronomic, disease-resistance, and nutritional characteristics.  It is anticipated that improved potato cultivars will help maintain the viability of rural economies, reduce dependence on pesticides, and contribute substantially toward maintaining a secure, safe and nutritious food supply.

Advanced Potato Clones Showing Particular Promise in 2015 include:

• AF4157-6 (Yankee Chipper x Dakota Pearl), an early to mid-season, round to oblong white with good yields, moderately-high gravity, very good chip color, and fair to good appearance.   U.S.#1 yields have averaged 95% of Atlantic and 108% of Snowden in Maine trials.  Specific gravity is moderate to high (average of 1.086 in ME trials) and chip color from storage has been very good.  It has low sugars even from cool temperature storage.  It is susceptible to scab, but has resistance to golden nematode, blackspot bruise, and pink rot.  AF4157-6 has potential as a chipper in southern states and in northern states on fields where scab is not a concern
• AF4138-8 (SA9707-6 x AF1953-4), a fresh market, early to mid-season, round to oblong white with bright skin.  It has good yields, attractive tubers, low specific gravity, blackspot bruise tolerance, low hollow heart incidence, and good boiled quality.   It is moderately resistant to scab and has golden nematode resistance
• AF4124-7 (A8469-5 x SC9512-4), a medium maturing, russet with good fry quality, fair tuber appearance, early sizing, and high yields.  US#1 yields have averaged ~119% of standard russeted varieties (usually Russet Burbank) in Maine trials.  Specific gravity is moderate (average of 1.085 in ME trials) and fry color from storage has been good.  It is moderately resistant to scab and has good blackspot bruise resistance. 
• AF4172-2 (A95523-12 x A92158-3), a medium maturing, russet with good fry quality, fair to good tuber appearance, and high yields.  US#1 yields have averaged ~119% of standard russeted varieties (usually Russet Burbank) in Maine trials.  Specific gravity is moderate (average of 1.083 in ME trials) and fry color from storage has been very good.  It has been a good performer in the national fry processing trials (NFPT).  It is susceptible to scab, but has good bruise resistance.  Tuber size tends toward the smaller size classes.  Baked quality scores have been very good.  
• AF4296-3 (A0508-4 x A99081-8), a widely adapted, late maturing, russet with good fry quality, fair tuber appearance, and high yields.  US#1 yields have averaged ~111% of standard russeted varieties (usually Russet Burbank) in Maine trials.  Specific gravity is moderate (average of 1.079 in ME trials) and fry color from storage has been good.  It has been an outstanding performer in the national fry processing trials (NFPT).  It is moderately susceptible to scab, but has moderate verticillium resistance and good bruise resistance.  
• AF4648-2 (NY132 x Liberator), a mid-season, round to oblong white with good yields, moderately-high gravity, bruise resistance, very good chip color, and good appearance.   It could go for chipping or fresh market.  It has good scab resistance and is resistant to golden nematode and PVY. 
• AF4659-12 (A99331-2 x US147-96RY), a yellow-fleshed “pinto-type” specialty variety with a interesting red and yellow skin pattern.  It produces small, fingerling-type tubers that are excellent roasted, boiled, or fried.

• AF4985-1 (ND8555-8 x ND4756-1) has bright red skin with a smooth, attractive skin finish, white flesh, good cooking quality, medium to medium-late vine maturity. Yields are often good, but have been inconsistent due to external tuber defects (primarily greening and growth cracks).  It has moderate scab resistance. 

• NY148 (NY128 x Marcy), a late-season, high specific gravity, chip stock clone.  It has round tubers with prominent skin netting.  Yields have been very high in many trials.  Chip color from storage is good, but not exceptional.   It has good scab resistance, moderate early and late blight resistance, PVY immunity, resistance to golden nematode (Ro1).  It is susceptible to internal heat necrosis and is quite susceptible to bruising. 
• NY150 (NY121 x Jacqueline Lee), a niche market, early-season, round-white for fresh market use.  It produces many small tubers with bright white skin.  It has moderate scab resistance, moderate late blight resistance, resistance to golden nematode (Ro1), and is immune to PVY. 
• NY154 (B38-14 x Marcy), a late-season, moderate to high  specific gravity, chip stock clone.  It has round to oblong tubers with netted skin.  Yields have been very high in many trials.  Chip color from storage is good, but not exceptional.   It has good scab resistance and moderate early blight resistance. 

Project milestones for 2015, and progress related to each of these, follow:

Conduct breeding, germplasm enhancement, and selection studies to improve potato productivity and quality for important eastern U.S. markets.

Breeding:  During 2015, our programs generated 673 new tetraploid families (622,000 seeds) from crosses using parents with desirable quality, utilization, adaptation, and/or pest resistance traits. USDA-ARS also generated 36 2x crosses (231,000 seeds) for use in germplasm improvement.  Progeny (109,110) from earlier crosses were selected resulting in 4,169 clones that will be further selected under conditions with diverse abiotic and biotic stress in the eastern U.S. and beyond. Crosses conducted by the University of Maine continue to emphasize (50%) russets for processing and fresh; however, a significant component of the program is represented by round whites and chipping types (40%) and specialty types (10%).  Cornell University and NC State University place strong emphasis on breeding for chip quality and utilization, but also include fresh market, colored-skin, and specialty types in their breeding goals.  Multi-site evaluation of early-generation clones is being used to speed the breeding and selection process through identification of broadly- and specifically-adapted clones.

USDA-ARS potato breeding at the tetraploid level typically focuses on chipping types and clones with colored skin and/or flesh.  The 4x-2x crosses in the USDA-ARS program partially focus on yellow-fleshed tetraploid S. tuberosum (tub) and orange-fleshed diploid S. phureja-S. stenotomum (phu-stn) to enhance the carotenoid content in tuberosum. The phu-stn combinations are also being used to enhance tuber specific gravity.  In addition, crosses were made between tub and hexaploid S. albicans or S. iopetulum to incorporate the nitrogen uptake efficiency of these hexaploid species into tuberosum  Also, crosses were made between diploid phu-stn and S. chacoense (chc) to incorporate the nitrogen uptake efficiency of chc into long-day adapted phu-stn.  In addition, 4x-2x or 2x-4x crosses were made between tub and cycle three late blight resistant phu-stn clones.     

53. hougasii based potato germplasm (E53.61 from USDA-WA, C. Brown) was crossed with three tetraploid clones from USDA-ARS Beltsville. The resulting 35 hybrid clones were screened for late and early blight resistance as well as chipping quality. Fourteen of these clones were resistant to both diseases, while three of these clones combined late blight resistance, early blight resistance, high specific gravity, and acceptable chip color from 10C storage.  This project will provide potato breeders with a valuable new source of disease resistance and chip quality.

Research on the genetics of internal heat necrosis (IHN) and the development of clones and populations with improved resistance to this tuber defect continued.  The test sites in NC, VA, NY, PA, and FL provide ideal environmental conditions for all four breeding programs to utilize in selecting for IHN resistance. The NC mapping population B2721 was genotyped with the Infinium^® 8303 SNP array developed by the USDA-NIFA SolCAP project and quantitative trait loci (QTL) were detected for IHN on chromosomes 1, 5, 9, and 12. Genetic effect models of the QTL explained roughly 28 and 25% of the variation for incidence and severity, respectively. Using the SNP gene annotations and the potato reference genome we have tentatively identified a candidate gene involved in IHN, vacuolar cation/proton exchanger 1a, that was closely linked to a QTL for IHN susceptibility. The B2721 population has also been phenotyped for chip color, specific gravity, and reaction to scab.  Molecular markers linked to all these traits are currently being developed.

VA Tech continues to develop 4x-2x hybrid families representing unusual genomic combinations of Solanum tuberosum Group Tuberosum and S. tuberosum Group Phureja where much of the Phureja genome has passed through the “monoploid sieve” to eliminate lethal and severely deleterious genes. The question is whether this purified Phureja genome can serve as a building block for new cultivars or if it will introduce too many undesirable traits for potato breeding purposes.  A round of preselection of diploid plant material was initiated where one parent of the diploid hybrids was a homozygous doubled monoploid clone. Forty seeds were planted of each of 23 families representing derivatives of four different doubled monoploids crossed to any of 11 heterozygous diploid clones. Depending on seed germination, tuberization, and elimination of seedlings with severe defects apparent in the greenhouse tubers, 375 tuberlings were sent to NC, 336 to VA Eastern Shore and 396 to Maine for field evaluation. Based on field evaluations in ME and VA, we selected 45 seedlings from 20 different diploid families to screen for 2n pollen.

Inbreeding studies have continued with a diploid population derived from a cross between the doubled monoploid (DM) used for potato genome sequencing and a heterozygous Dutch clone (RH) for which considerable genome sequence is available. Self-fertility was observed among the F1 seedlings, and the self-fertile plants have now been advanced to the S7 generation. Analysis of 91 of the S3 individuals on the Illumina 8303 Potato SNP Array revealed preserved regions of heterozygosity much greater than expected on chromosomes1, 2, 5 and 11. These regions likely house genes required for fertility and vegetative vigor in order to engender functional gametes for advancement of generations. As the generations advance, nonessential heterozygosity can be expected to be removed as a result of genetic recombination. Residual heterozygosity in the S6 lines ranged from 36 to 139 SNP loci of 12,000 SNP loci evaluated on the Array.

Selection:  USDA-ARS and ME send seed from all clones in the second or third field generation (12-hill or 60-hill stage) to cooperators in FL and NC for early generation evaluation and to select materials with adaptation to the short-season Southeastern U.S. environmental.  All of our programs send seed from more advanced field generations (third and higher) to regional cooperators (FL, NC, VA, PA, OH, NY, ME) for continued phenotyping, selection, and advancement.  Advanced clones from our project were introduced to growers through field days, presentations, publications, web sites, and direct contact with stakeholders.  Seven advanced clones were entered into tissue culture programs leading to commercial seed production.  

Use of novel and highly improved potato germplasm to reduce the impact of economically important potato pests in the eastern U.S.

The project places special emphasis on breeding and selecting clones with resistance to late blight, early blight, scab, golden nematode races Ro1 and Ro2, potato virus Y (PVY), and heat necrosis. Disease resistant varieties generated by this project have the potential to greatly reduce growers’ losses to devastating diseases such as late blight and can also reduce production costs and environmental risk by reducing the number of chemical sprays applied to protect the crop. Golden nematode, a serious pest found in NY and other countries, cannot be effectively managed without resistant varieties.

Wild or cultivated diploid germplasm that we are using to introduce novel traits for pest resistance or improved quality includes:  S. phureja and S. stenotomum for resistance to early and late blight (USDA-ARS); S. bulbocastanum for late blight and insect resistant (ME), S. chacoense for insect resistance (USDA-ARS, NC); S. hougasii for late blight resistance (USDA-ARS); and S. berthaultii for insect resistance (NY, NC).  In addition, 4x-2x or 2x-4x crosses were made between tub and cycle three late blight resistant phu-stn clones. 

Golden nematode: Breeding efforts in NY have emphasized resistance to golden nematode Ro1; however, resistance to race Ro2 is now also a priority.  The NY program developed Ro2 resistance by selecting for adaptation within a collection of South American tetraploids, and work has begun to procure additional sources of resistance from Europe to broaden the genetic base of resistance and provide resistance to G. pallida.  All NY round whites, and most of the NY colored crosses, segregate for resistance to golden nematode Ro1 or Ro2, as do many crosses from the ME and USDA programs.  The USDA-ARS and ME programs also use parental materials with nematode resistance.  Progeny from crosses using resistant parents are being evaluated for resistance to both races of the golden nematode (NY and USDA-ARS).  NY’s H1 PCR-based marker is also being also used to screen clones for Ro1 resistance (NY, ME).  NY is also testing for resistance to G. pallida using in vitro techniques.

Late and early blight:  The most promising late blight resistant selections from ME, NY, and USDA-ARS undergo field evaluation for resistance in PA within the NE-1231 regional project. Thirty-two clones were screened for resistance during 2015.  Three experimental NE-1231 clones (Palisade Russet, AF4648-2, and CO00291-5R) were resistant in these trials, while two were moderately resistant (AF4953-6, NY154). Forty (of  280) third-year and 38 (of 127) advanced clones from the ME program had late blight resistance in 2015 tests and will be further evaluated during 2016.  AF4296-3, AF4648-2, AF4953-6, AF4975-3, CO00291-5R, and NY154 were moderately resistant to early blight in PA trials during 2015.   

A diploid S. phureja-S. stenotomum population, resulting from a cross of a highly resistant late blight clone x a susceptible clone, is currently being generated and will be used to map genes involved in late blight resistance in this population using the SolCap-derived SNP chip (USDA-ARS, PA). Additional selection for late blight resistance occurred in a cooperative project between USDA-ARS and PA.  USDA-ARS maintains a diploid Solanum phureja-S. stenotumum population (phu-stn) that has undergone multiple selection cycles for resistance. The levels of resistance in the diploid phu-stn population increased dramatically over multiple selections cycles. To avoid narrowing the genetic base, the most resistant clone from each maternal half-sib family was planted in a seed nursery, and open-pollinated seed was collected to advance the population to the next selection cycle. Clones with high levels of resistance were screened for 2n pollen production, and those that produced at least 5% 2n pollen were utilized in 4x-2x crosses. Hybrids between tuberosum and late blight resistant diploids have now proceeded through four cycles of resistance selection.  Mini-tubers from the cycle four diploid late blight population were sent to Toluca, Mexico for testing against late blight in an area with a highly diverse pathogen population.  Resistant clones from this breeding effort have been utilized in 4x-2x crosses to tuberosum to transfer this resistance into the tetraploid population and these materials will continue to be developed. 

53. hougasii based potato germplasm (E53.61 from USDA-WA, C. Brown) was crossed with three tetraploid clones from USDA-ARS Beltsville. The resulting 35 hybrid clones were screened for late and early blight resistance. Sixteen had good resistance to late blight, while 23 were moderately to highly resistant to early blight.  Fourteen of these clones were resistant to both diseases.  This project will provide potato breeders with a valuable new source of resistance to both diseases.

Scab: ME, NY, PA, and USDA-ARS screen and select for resistance to scab in inoculated and/or naturally-infected field experiments.  Lines are tested over multiple years because of environmental effects on disease incidence and severity.  Scab resistant parents are used extensively in all four breeding programs.  Clones showing resistance are being used as parents to improve the level of resistance in future germplasm.  Twenty-three experimental NE-1231 clones were compared with standard varieties in two University of Maine scab screening trials during 2015.  Ten (Teton Russet, Sebec, Caribou Russet, AF4138-8, AF4124-7, AF4648-2, AF4975-3, AF4985-1, CO00291-5R, and NY154) were moderately resistant or resistant in these trials.  Including 4^th-year, advanced, and NE-1231 clones, 67 of 177 University of Maine selections had scab resistance in our 2015 screening trial. 

Potato Virus Y (PVY) As a result of the NY neotuberosum project, extreme resistance to PVX and PVY is present in many NY breeding lines.  The variety Eva, for example, is immune to both PVX and PVY.   All four breeding programs continue to include virus-resistant clones as parents. Marker-assisted selection for potato virus Y resistance (Whitworth et al. 2009; Ry_adg, RYSC3, Kasai et al, 2000; Ry_sto, YES3, Song and Schwarzfischer 2008) are being used to supplement traditional screening methods and provide earlier detection of resistant clones. AF4648-2, a promising white-skinned variety that is being commercially evaluated for fresh and chipping markets, has resistance to scab, late blight, PVY, pink rot, and golden nematode. Several promising clones from the NY program (e.g. NY148, NY150) also have PVY resistance.

Colorado Potato Beetle: Horticultural evaluation of glandular-trichome- producing advanced lines continues within the Cornell NY breeding program.  Crossing at the diploid level is also being undertaken to reinitiate the introgression of trichome traits from S. berthaultii into S. tuberosum.  All current CPB-resistant lines are derived from a handful of crosses between tetraploid S. tuberosum and unreduced pollen from diploid S. berthaultii.   A frequent association between insect resistance and unacceptable levels of tuber glycoalkaloids has been difficult to eliminate while selecting at the 4x level.  Current tetraploid lines also lack the acyl-sugar secreting, type B trichomes present in S. berthaultii.  In a complementary effort, NCSU has used the USDA-ARS-developed tetraploid S. chacoense (2n=4x=48) potatoes crossed with S. tuberosum (Sanford et al., 1997) to develop CPB resistant germplasm. During 2006-2015, NCSU has used several of the most promising advanced chc-based CPB-resistant lines in crosses with Cornell University’s S. tuberosum X S. berthaltii derived materials.  Field evaluation of these materials continued in 2015.

Selection:  Each of the breeding programs maintain plots for resistance screening (e.g. NC, CPB resistance; ME, scab, verticilliun, late blight, pink rot, fusarium, PVY and PLRV; NY late blight, scab, insect resistance, PVY; USDA-ARS late blight, scab; and/or or utilize regional collaborators (USDA-ARS NY for golden nematode resistance; Penn State for late blight, early blight, and powdery scab). Marker-assisted selection is being used to speed selection for PVY and golden nematode resistance.

Short-term Outcomes:

1. Eastern potato growers need new potato varieties which are highly productive and less susceptible to stress, diseases, and insects than current varieties. This regional potato breeding and trial network produces new potato varieties and evaluates their potential to serve fresh, processing, and specialty potato markets in the East.  These new varieties will improve grower profitability by increasing yields, enhancing market quality, and/or decreasing costs associated with pests.   Farm gate receipts for eastern potato production exceed 460 million dollars annually, therefore the impact of a successful new potato cultivar can mean many millions of dollars to the industry over time. Potatoes can cost more than $2500 per acre to produce and devastating diseases such as pink rot and/or late blight can totally destroy the crop.  Resistant varieties greatly decrease the risk of losses and, in the case of late blight resistance, can reduce production costs by reducing the number of chemical sprays applied to protect the crop from the pest.  Several areas in NY could not produce potatoes without the golden nematode resistant varieties developed as part of this and other research projects. 

2. Over the years, the eastern regional project has resulted in the release of many commercially important potato varieties (e.g. Atlantic, Andover, Harley Blackwell, Kanona, Keuka Gold, MaineStay, Marcy, Monticello, Pike, and Sunrise). Peter Wilcox, a purple-skinned yellow-fleshed specialty variety from the USDA-ARS program, and Lehigh, a yellow-fleshed dual-purpose variety from NY, are two of the more recent releases from the eastern programs.  Lamoka (NY139), Waneta (NY138), and Red Maria (NY129) are three 2010-2011 releases that are attracting commercial interest.  Elkton (B1992-106) was released in 2012, while Sebec (AF0338-17) and Easton (AF3001-6) were released in early 2014.  Caribou Russet (AF3362-1) and Little Ruby (B2152-17) were released in 2015.  Potato seed multiplication and commercial adoption are slow processes; therefore, so it will take years to know the full impacts of these varieties on eastern potato production. 

3. To facilitate the adoption process, ME coordinated 22 commercial-scale trials representing 8 new potato varieties (3 chippers, 1 round-white, 3 russets, and 1 specialty type) and 102 acres during 2015. Eastern releases since 2002 were grown on 1,312 ME and NY seed acres during 2015 with a potential seed value of $3.9M.  The resulting seed crop had the potential to plant 12,021 acres in 2015 with a ware value estimated at $36.1M.  Over a longer time frame, 39 of the ~140 varieties listed in the ME and NY certified seed directories were released by the Eastern programs since 1990. These releases represent 2251 seed acres with a potential seed value of $6.8M.  This seed crop has the potential to plant 22,513 acres in 2016 with a projected value of $67.5M. This excellent rate of adoption will grow over time as the industry builds seed supplies.  Depending on the characteristics of the specific potato variety, the potential benefits of adoption include new marketing opportunities, more efficient processing, higher yields, better nutritional value, reduced pesticide costs, and less risk of losses to stress, diseases, and pests.

4. Our project web site and searchable database continues to grow in size and utility (http://potatoes.ncsu.edu/NE.html). The web site provides current contact information for project cooperators and recent research reports, as well as access to our regional variety database and a dynamic summary generator for all released varieties. The interactive database can be viewed at <http://potatoes.ncsu.edu/nesrch.php>.

Outputs:

1. Cultivars released this year:

Caribou Russet (tested as AF3362-1) is a mid-season, long russet with good yields, processing potential, and fair to good appearance.  Caribou Russet is very good baked and mashed.  It was released in February 2015 by the University of Maine.  Plant variety protection has been granted and it is licensed by the Maine Potato Board.  Commercialization is underway.  Total yields in Maine trials were very high, averaging 354 cwt/A (109% of Russet Burbank), while US#1 yields averaged 327 cwt/A (126% of Russet Burbank).  Specific gravity is moderate averaging 1.082 in ME trials compared to 1.081 for the Russet Burbank standard.  Caribou Russet tubers are large, but it has had a low incidence of tuber hollow heart (3.0% versus 13.8% for Russet Burbank).  It may be a good alternative to Shepody for out-of-field and short-term storage processing use as well as useful for russet fresh market.   It has moderate scab resistance and good bruise resistance.  Caribou Russet is susceptible to internal heat necrosis and should not be grown in the S.E. states or other areas where this defect is frequently observed

Little Ruby (tested as B2152-17) is a red-skinned, yellow-fleshed variety for the specialty potato market.  Little Ruby is early maturing with small tubers, smooth red skin and shallow eyes.  Incidence of internal and external tubers defects has been minimal.  Yields tend to significantly lower than standard red-skinned varieties; however, its high quality tubers should capture premium prices in the specialty trade.  It has moderate common and powdery scab resistance.

Publications:

Journal Papers

Chen S., Lang P., Chronis D., Zhang S., De Jong W., Mitchum M.G., Wang X.  2015.  In planta processing and glycosylation of a nematode CLE effector and its interaction with a host CLV2-like receptor to promote parasitism.  Plant Physiology 167: 262-272.

Haynes, K.G., Yencho G.C., Clough M.E., Henninger M.R., Qu X.S., Christ B.J., Peck M.W., Porter G.A., Hutchinson C.M., Gergela D.M., Halseth D.E., Menasha S.R., and Sieczka J.B.  2015.  Peter Wilcox: a new purple-skin, yellow-flesh fresh market potato cultivar with moderate resistance to powdery scab.  American Journal of Potato Research 92: 573-581.

Makani, M.N., S.A. Sargent, L. Zotarelli, D.J. Huber, C.A. Sims. 2015. Irrigation method and harvest time affect storage quality of two early-season, tablestock potato (Solanum tuberosum L.) cultivars. Scientia Horticulturae. 197: 428-433.

Qu X.S., Peck M.W., Moore C.E., Christ B.J.  2015.  Field evaluation of potato cultivars and breeding lines for resistance to late blight in Pennsylvania, 2014.  Plant Disease Management Reports 9: V040.

Qu X.S., Peck M.W., Moore C.E., Christ B.J.  2015.  Field evaluation of potato cultivars and breeding lines for resistance to early blight in Pennsylvania, 2014.  Plant Disease Management Reports 9: V039.

Qu X.S., Peck M.W., Moore C.E., Christ B.J.  2015.  Evaluation of foliar fungicides for control of potato late blight in Pennsylvania, 2014.  Plant Disease Management Reports 9: V038.

Qu X.S., Peck M.W., Moore C.E., Christ B.J.  2015.  Field evaluation of potato cultivars and breeding lines for resistance to powdery scab in Pennsylvania, 2014.  Plant Disease Management Reports 9: V037.

Rens, L.R., L. Zotarelli, D.J. Cantliffe, P. Stoffella, D. Gergela, D. Fourman. 2015. Rate and timing of nitrogen fertilizer application on potato 'FL1867' Part II: Marketable yield and tuber quality. Field Crops Research. 183: 267-275.

Rens, L.R. , L. Zotarelli, D.J. Cantliffe, D. Gergela, P. Stoffella, D. Fourman. 2015. Biomass accumulation, marketable yield, and quality of Atlantic potato in response to nitrogen. Agronomy Journal. 107: 931-942.

Wang, Y., P.C. Bethke, A.J. Bussan, M.T. Glynn, D.G. Holm, F.M. Navarro, R.G. Novy, J.P. Palta, M.J. Pavek, G.A. Porter, V.R. Sathuvalli, A.L. Thompson, P.J. Vogelwede, J.L. Whitworth, D.I. Parish, and J.B. Endelman.  2015.  Acrylamide-forming potential and agronomic properties of elite US potato germplasm from the national fry processing trial.  Crop Sci. 56:1-10.

Zotarelli, L., L.R. Rens, D.J. Cantliffe, D. Gergela, P. Stoffella, D. Fourman. 2015. Rate and timing of nitrogen fertilizer application on potato 'FL1867' Part I: plant nitrogen uptake and soil nitrogen availability. Field Crops Research. 183: 246-256.

Technical Articles or Reports, not refereed

De Jong, W., D. Halseth, M. Falise, and S. Menasha.  2015.  New York potato breeding program ‘show and tell” grower report, 2015.  Research Report, Cornell Department of Plant Breeding and Genetics, 42 pp.

Kleinhenz, M.D., J.B. Moyseenko, S.D. Walker, and B. Williams.  2015.  Ohio Potato Germplasm Evaluation Report, 2015.  The Ohio State University, Horticulture and Crop Science Series No 838, 20 pp.

Porter, G.A., P. Ocaya, B. MacFarline, and B. Plummer.  2015.  Potato variety trial results in Maine, 2015 growing season.   SFA Research Report (posted on www and distributed to industry), 2015-01, 42 pp.

Porter, G.A., P. Ocaya, and T. Mills.  2015.   Maine potato breeding program annual report,  2015 growing season.   SFA Research Report (posted on www and distributed to industry), 20 pp.

Qu, X. and B.J. Christ.  2015.  Pensylvania Potato Research Report, 2015.  Dept of Plant Pathology & Environmental Biology, The Pennsylvania State University, University Park, PA, 32 pp.

Yencho, G.C. and M.E. Clough. 2015. North Carolina Potato Variety Trial and Breeding Report, 2015. NC State University, Raleigh, NC. 50 pp. < http://potatoes.ncsu.edu/Reports.html

Zotarelli, L.  2015. Florida Potato Variety Trial Report, 2015. University of Florida, Horticultural Sciences Department. Report. 132 pages. The book is also available at: http://hos.ufl.edu/extension/variety-trials/variety-trial-crops/potatoes