Brief Summary of Minutes of Annual Meeting

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 2016. 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 2016, our programs generated 661 new tetraploid families (546,750 seeds) from crosses using parents with desirable quality, utilization, adaptation, and/or pest resistance traits. USDA-ARS also generated 56 diploid crosses (2x or 4x-2x; 49,500 seeds) for use in germplasm improvement.  Progeny (96,416) from earlier crosses were field selected resulting in 4517 clones that will be further selected during 2017 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.  NY’s two most recent chipping releases are Waneta (NY138) and Lamoka (NY139). Based on certified seed acreage in 2016, Lamoka (2366 acres) has now replaced Snowden (1692 acres) as the standard storage chipping variety across the U.S.  Waneta has also been widely adopted (713 acres of seed in 2016).  We estimate the value of potato chip production from Lamoka and Waneta for 2017 will be one billion dollars (~15% of US chip production).  From ME, Sebec (AF0338-17) continues to be commercially adopted for out-of-field chipping and fresh market use due to its outstanding yields and improved resistance to internal defects compared to the current standard, Atlantic. Twelve clones from the eastern states have been in the Potatoes USA fast-track chip program since 2011, and the programs supported under this grant have annually contributed up to 40% of clones in the Potatoes USA National Chip Processors Trials (NCPT).

For fresh market, USDA-ARS released Little Ruby (B2152-17) during 2015 and NY released Strawberry Paw (NY136) during 2013. Both varieties are attractive, red-skinned potato varieties for high-value fresh market use. Other fresh market releases Red Maria (2010), a high-yielding red, Lehigh (2007), a widely-adapted yellow-fleshed variety, and Peter Wilcox (2007), a novel purple-skinned, yellow-fleshed variety continue to be adopted by fresh market growers.  NY150 is a specialty white with very small, bright tubers.  There has been considerable interest among specialty growers and it is being successfully commercialized.  AF4659-12, is a pinto-type, yellow-fleshed ‘roasting’ variety that is being commercialized by small-scale local foods markets.

Caribou Russet (AF3362-1) was released during 2015 for fry processing and russet fresh market.  It is being rapidly adopted due to high yields, scab and verticillium resistance, and excellent consumer quality. AF4124-7, AF4172-2, and AF4296-3 are advanced fry processing clones that are generating strong commercial interest.  Twenty additional French fry clones are currently being evaluated by North American potato processors.

Each eastern breeding program submits its most promising advanced clones to the regional project’s seed nursery in ME.  During 2016, the project distributed seed potatoes for 12 regional potato variety trials conducted in six states and two Canadian provinces.  Eleven standard varieties and 20 experimental clones were tested for yield, tuber quality, and pest resistance.  NE1231 Regional potato variety trials were conducted at three ME locations during 2016.  The regional trial sites (numbers of clones tested) were: Presque Isle (29), St Agatha (30), and Exeter (15).   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 2016 Maine results, AF4648-2, AF5040-8, NY154, and NY157 were the most outstanding chipping prospects.  AF4138-8, AF4552-5, AF4648-2, and AF5280-5 were promising round-white fresh market clones.  AF4831-2 and AF5245-1 were promising reds and specialty clones.  Caribou Russet, Reveille Russet, Teton Russet, 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 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 2016 include:

• 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.

• AF4831-2 (ND028946B-1 x ND8555-8) has bright red skin with a smooth, attractive skin finish, round to oblong tuber shape, white flesh, good cooking quality, medium to medium-late vine maturity. Yields are often good, but tuber size tends to be quite small).  It has moderate scab resistance along with verticillium wilt and blackspot bruise resistance.

• AF5312-1 (A86106-6 x CO82142-4), a medium maturing, fresh market russet with good appearance, flavor, and high yields.  US#1 yields have averaged ~143% of standard russeted varieties (Russet Burbank and Russet Norkotah) in Maine trials.  Specific gravity is moderate (average of 1.078 in ME trials) It is resistant to scab and has good blackspot, shatter, and fusarium. 
• 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. 
• NY152 (B38-14 x Marcy), a late-season, moderate to high  specific gravity, chip stock clone with excellent chip color from storage.  It has round to oblong tubers with netted skin.  Yields have been very high in many trials.  It has good scab resistance and may be resistant to potato virus Y.    Hollow heart susceptibility is sometimes a concern.
• 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. 
• NY157 (White Pearl x NY115), a mid-season, moderate to high specific gravity, chip stock clone.  It has round to oblong tubers with netted skin. Yields have been high in many ME, NY, and PA trials.  Chip color from storage is very good.  It has low incidence of internal and external defects. It has moderate scab resistance and is resistant to golden nematode (Ro1). 

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, Little Ruby, a red-skinned, yellow-fleshed variety from USDA-ARS, and Lehigh, a yellow-fleshed dual-purpose variety from NY, are three of the more recent fresh market 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.  For chipping markets, NY’s two most recent chipping releases are Waneta (NY138) and Lamoka (NY139). Based on certified seed acreage in 2016, Lamoka (2366 acres) has now replaced Snowden (1692 acres) as the standard storage chipping variety across the U.S.  Waneta has also been widely adopted (713 acres of seed in 2016).  We estimate the value of potato chip production from Lamoka and Waneta for 2017 will be one billion dollars (~15% of US chip production).  From ME, Sebec (AF0338-17) continues to be commercially adopted for out-of-field chipping and fresh market use due to its outstanding yields and improved resistance to internal defects compared to the current standard, Atlantic. Twelve clones from the eastern states have been in the Potatoes USA fast-track chip program since 2011, and the programs supported under this grant have annually contributed up to 40% of clones in the Potatoes USA National Chip Processors Trials (NCPT).

3. Recent Eastern releases were grown on 2,382 ME and NY seed acres during 2016 with a seed value of ca. $7.2M. The resulting seed crop has the potential to plant 23,823 acres in 2017 with a ware value estimated at $71.5M.  Nationally, varieties produced by our long-term project were grown on 4,793 seed acres during 2016 with an approximate seed value of $14.4M   Several varieties developed though our collective efforts are currently in the top 100 U.S. varieties including (acres, rank): Lamoka (2367, 10), Waneta (713, 29), Pike (359, 50), Lehigh (260, 57), Reba (170, 66), Caribou Russet (143,71), Keuka Gold (106, 79), Eva (95, 83), and Andover (74, 98).

4. The project places special emphasis on breeding and selecting clones with resistance to late blight, early blight, scab, golden nematode races Ro1 and Ro2, and potato virus Y (PVY). Fifty-eight advanced breeding clones in the ME program showed high levels of late blight resistance during 2016. Five of 17 advanced eastern clones were moderately resistant to early blight in 2016 PA trials. Marker-assisted selection is being used to speed the development of PVY and golden nematode resistant varieties. 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, NC and USDA programs. AF4648-2, a promising white-skinned variety that is being commercially evaluated has resistance to scab, late blight, PVY, pink rot, and golden nematode.  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. Golden nematode, a serious pest found in NY and in other countries, cannot be effectively managed without resistant varieties.

5. 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:

Our project did not release any new potato varieties during 2016; however, commercialization of our recent releases continued as is summarized above.  Research trials and commercial evaluation of our advanced clones continued throughout 2016. 

 Project milestones for 2016, 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 2016, our programs generated 661 new tetraploid families (546,750 seeds) from crosses using parents with desirable quality, utilization, adaptation, and/or pest resistance traits. USDA-ARS also generated 56 diploid crosses (2 x or 4x-2x; 49,500 seeds) for use in germplasm improvement.  Progeny (96,416) from earlier crosses were selected resulting in 4,517 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 site in NC provides good environmental conditions that all four breeding programs utilize in selecting for IHN resistance. In 2016, NC screened a total of 699 early generation clones. Of these 240 were from NC, 251 from ME, 77 from the USDA-ARS Beltsville, and 131 clones were from the NCPT (with clones from CO, ME, MI, NC, NY, OR, TX, USDA-MD and WI).  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 explained roughly 28 and 25% of the variation for IHN incidence and severity, respectively and we have tentatively identified several candidate markers for IHN susceptibility. The B2721 population has also been phenotyped for chip color, specific gravity, and scab reaction. QTL analyses of these traits is underway. Because sufficient funding is not available to carry the QTL studies forward within this USDA-NIFA program, we are looking for additional support to advance this research.

VA studies are in progress to associate physiological processes responsive to environmental stresses with IHN development. Specifically, the activity of catalase and peroxidase, key factors of the reactive oxygen species (ROS) scavenging system, appear to be associated with temperature increases above 30°C and varies with cultivar. However, the association of membrane integrity (leakage) with IHN was inconclusive at this time. Studies to determine the tuber phenolic content in response to temperature are in progress.

VA continues conducting field evaluations of 4x-2x hybrids, preliminary selections and advance breeding lines from the eastern breeding programs. During 2017, 267 4x-2x hybrids from the VA potato genetics program are being field screened for performance in VA.  Yield, quality, and responses to stressing temperatures are evaluated since they are critical factors in selecting suitable varieties for production in VA.

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, and potato virus Y (PVY). Fifty-eight advanced breeding clones in the ME program showed high levels of late blight resistance during 2016.  Five of 17 advanced eastern clones were moderately resistant to early blight in 2016 PA trials. Marker-assisted selection is being used to speed the development of PVY and golden nematode resistant varieties. 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, NC and USDA programs. AF4648-2, a promising white-skinned variety that is being commercially evaluated has resistance to scab, late blight, PVY, pink rot, and golden nematode.  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. Golden nematode, a serious pest found in NY and in 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. Resistances to race Ro1 of the golden nematode (Globodera rostochiensis) and to common scab (Streptomyces scabies) have long been priorities of the NY program.  Recent Ro1 resistant releases have achieved commercial success, including Andover, Pike, Reba, Marcy, Lehigh, Waneta and Lamoka.  All of these varieties also have moderate to good resistance to common scab.  All clones that have survived three or more years of selection in NY are evaluated for resistance to golden nematode race Ro1 as well as common scab each year. USDA-ARS in NY provides golden nematode screening for the eastern programs and 18 of 65 ME clones (27.7%) showed resistance during 2016.

Late and early blight:  PA serves as the project’s key screening site for resistance to several important potato diseases.  Early selection for late blight resistance with the ME and USDA-ARS Beltsville breeding programs occurs there.  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-one advanced NE1231 clones were screened for resistance during 2016.  Five experimental NE-1231 clones were resistant in the 2016 trials (AF4648-2, AF4615-5, AF4953-6, CO00291-5R, and NY154).  Seventy (of  231) third-year and 58 (of 95) advanced clones from the ME program had late blight resistance in 2016 tests and will be further evaluated during 2017.  AF4296-3, AF4615-5, AF4648-2, AF4953-6, BNC244-10, and CO00291-5R were moderately resistant to early blight in PA trials during 2016.   

During 2016, a tetraploid mapping population of 260 clones from USDA-ARS Beltsville, a diploid crossing population of 283 lines from USDA-ARS Beltsville, and five breeding lines from NC were evaluated for late blight resistance.  Late blight resistant clones were selected as a result of this research. Resistance genes/QTLs will be mapped on the tetraploid mapping population. 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.  The University of Maine and several other North American Potato Breeding programs are already using this new late blight resistant material in their crossing programs.

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 experimental NE-1231 clones were compared with standard varieties in two University of Maine scab screening trials during 2016.  Nine (Reveille Russet, Teton Russet, AF4138-8, AF4648-2, AF4953-6, AF4985-1, AF5245-1, AF5280-5, and NY154) were moderately resistant or resistant in these trials.  Including 4^th-year, advanced, and NE-1231 clones, 62 of 139 University of Maine selections had scab resistance in our 2016 screening trial. 

The NE1231 cultivars and advanced breeding lines were also evaluated for powdery scab resistance on a farmer’s farm in Potter County, PA. Eight out of 32 were characterized resistant to moderately powdery scab resistant.  These were Caribou Russet, Russet Burbank, Teton Russet, AF4138-8, AF4296-3, AF4615-5, AF4953-6, and NY154.

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, and pink rot. Several promising clones from the NY program (e.g. NY148, NY150) also have PVY resistance.

Colorado Potato Beetle: NC continued to select and screen specific families with potential Colorado potato beetle CPB resistance.  For the first cycle of selection in 2016, they changed from screening duplicated 2-hill plots for CPB resistance and adaptability separately, to a single 4-hill plot and selected on yield and overall appearance.  This is because NC is now planting all trials at the research station with a 2-row carousel planter and 2-hill plots are difficult to keep organized, whereas 3- and 4-hill plots are manageable. NC planted 969 4-hill plots for selection purposes.  They selected 330 clones that were advanced for CPB screening as two replicated 3-hill plots (2by3 trial), and for parallel horticultural adaptation selection as non-replicated 6-hill plots in 2017.  In the 2016 2by3 trial, 40 clones were simultaneously evaluated for CPB resistance and adaptation in non-replicated 6-hill plots.  After making selections in both of these trials, NC advanced 7 clones to the 2017 screening trial of three replications with 5-hills each (3by5 trial) and parallel horticultural adaptation selection in non-replicated 20-hill plots.  In the 2016 3by5 trial, NC simultaneously evaluated 17 clones for CPB resistance and for adaptation in non-replicated 20-hill plots.  NC selected 6 clones for advancement to the 2017 four replications by 10-hills (4by10) screening plots and non-replicated 60-hill trial.  In the 2016 4by10 we had a total of 5 clones and 2 of those were selected for evaluation in 2017. The 4by10 trial is our most advanced screening trial and the most advanced clones will remain in this trial until testing is complete, also some of the clones with promise will be placed in yield trials if they have the appropriate agronomic characteristics.  New varieties with high levels of natural CPB resistance have potential to facilitate production of potatoes with fewer pesticides contributing to the sustainable crop production.

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.

2. Publications:

Journal Papers

Publications (peer-reviewed journals):

Bamberg J.B, Martin M.W., Abad J., Jenderek M.M., Tanner J., Donnelly D.J., Nassar A.M.K., Veilleux R.E., Novy R.G.,  2016.  In vitro technology at the US Potato Genebank. In Vitro Cell Dev Biol Plant 52: 213-225

De Jong, W.S., D.E. Halseth, R.L. Plaisted, X. Wang, K.L. Perry, K.M. Paddock, M. Falise, B.J. Christ, and G.A. Porter. 2016. Lamoka, a variety with excellent chip color out of cold storage and resistance to the golden cyst nematode.   American Journal of Potato Research DOI 10.1007/s12230-016-9557-x.

Haynes, K.G., Qu X.S.  2016.  Late blight and early blight resistance from Solanum hougasii introgressed into Solanum tuberosum.  American Journal of Potato Research 93: 86-95.

Jansky, S.H., Charkowski A.O., Douches D.S., Gusmini G., Richael C., Bethke P.C., Spooner D.M., Novy R.G., De Jong H., De Jong W.S., Bamberg J.B., Thompson A.L., Bizimungu B., Holm D.G., Brown C.R., Haynes K.G., Sathuvalli V.R., Veilleux R.E., Miller J.C., Bradeen J.M., Jiang J.M.  2016.  Reinventing potato as a diploid inbred line–based crop. Crop Sci 56: 1412-1422

Kolech S.A., D. Halseth, P. Perry, D. Wolfe, D.S. Douches, J. Coombs, W. De Jong.  2016. Genetic Diversity and Relationship of Ethiopian Potato Varieties to Germplasm from North America, Europe and the International Potato Center. American Journal of Potato Research 93: 609-613.  doi:10.1007/s12230-016-9543-3

Oluwatosin, E.A., S.D. Johanningsmeier, V-D. Truong, and G. C. Yencho. 2016. Development and validation of a near-infrared spectroscopy method for the prediction of acrylamide content in french-fried potato. J. Agric. Food Chem. 64:1850−1860.

Peterson, B.A., Holt S.H., Laimbeer F.P.E., Doulis A.G., Coombs J., Douches D.S., Hardigan M.A., Buell C.R., Veilleux, R.E.  2016.  Self-Fertility in a Cultivated Diploid Potato Population Examined with the Infinium 8303 Potato Single-Nucleotide Polymorphism Array. The Plant Genome 9:1-13.

Qu X.S., Peck M.W., Moore C.E., Christ B.J.  2016.  Evaluation of foliar fungicides for control of potato late blight in Pennsylvania, 2015.  Plant Disease Management Reports 10: V008.

Qu X.S., Peck M.W., Moore C.E., Christ B.J.  2016.  Field evaluation of potato cultivars and breeding lines for resistance to powdery scab in Pennsylvania, 2015.  Plant Disease Management Reports 10: V035.

Qu X.S., Peck M.W., Moore C.E., Christ B.J..  2016.  Field evaluation of potato cultivars and breeding lines for resistance to late blight in Pennsylvania, 2015.  Plant Disease Management Reports 10: V036.

Qu X.S., Peck M.W., Moore C.E., Christ B.J.  2016.  Field evaluation of potato cultivars and breeding lines for resistance to early blight in Pennsylvania, 2015.  Plant Disease Management Reports 10: V037.

Raymundo, R., S. Asseng, R. Prassad, U. Kleinwechter, J. Concha, B. Condori, W. Bowen, J. Wolf, J.E. Olesen, Q. Dong, L. Zotarelli, M. Gastelo, A. Alva, M. Travasso, R. Quiroz, V. Arora, W. Graham, C. Porter. 2016.  Performance of the SUBSTOR-potato model across contrasting growing conditions. Field Crops Research. doi:10.1016/j.fcr.2016.04.012.

Rosyara U.R., P.C. Bethke, W.S. De Jong, S.H. Jansky, D.S. Douches, and J.B. Endelman.  2016.  Software for genome-wide association studies in autopolyploids and its application to potato.  The Plant Genome 9 (2), doi:10.3835/plantgenome2015.08.0073.

Technical Articles or Reports, not refereed

Arancibia, R. 2016. Virginia Potato Variety Trial Report - 2016. 

Arancibia, R.A. 2017. Potato. In Wyenandt (Coordinator), Elsa Sanchez (Hort. Ed.), 2016-2017 Mid-Atlantic Commercial Vegetable Production Recommendations (2017 revision). VCE publication 456-420 (AREC-203P) http://www.pubs.ext.vt.edu/456/456-420/456-420.html

De Jong, W.S., R. Plaisted, D.E. Halseth, and S. Menasha. 2016. New York Potato Variety Trial and Breeding Report - 2016, 38 pp.

Kleinhenz, M.D., J.B. Moyseenko, S.D. Walker, and B. Williams.  2016. Ohio Potato Germplasm Evaluation Report - 2016, 17 pp. Also available at https://potatoes.ncsu.edu/NEReports.html

Porter, G.A., P. Ocaya, B. MacFarline, and B. Plummer.  2016.  Potato variety trial results in Maine, 2016 growing season.   SFA Research Report (posted on www and distributed to industry), 2016-01, 42 pp. Also available at https://potatoes.ncsu.edu/NEReports.html

Porter, G.A., P. Ocaya, and T. Mills.  2016.   Maine potato breeding program annual report,  2016 growing season.   SFA Research Report (posted on www and distributed to industry), 20 pp.  Also available at https://potatoes.ncsu.edu/NEReports.html

Qu, X. and B.J. Christ.  2017. Pennsylvania Potato Research Report and Supplemental Report - 2016, 56 pp. Also available at https://potatoes.ncsu.edu/NEReports.html

Yencho, G.C. and M.E. Clough. 2016. NC Potato Variety Trial and Breeding Report - 2016, 44pp. Also available at https://potatoes.ncsu.edu/Potato.html

Yencho, G.C. and M.E. Clough. 2016. NE1231 NC Potato Variety Trial Report - 2016. 11 pp.  Also available at https://potatoes.ncsu.edu/NEReports.html

Zotarelli, L. 2016. Florida Potato Variety Trial Report - 2016, 113 pp. Also available at http://hos.ufl.edu/extension/variety-trials/variety-trial-crops/potatoes