1a. Objectives (from AD-416)
Objectives of this research are the development of potato varieties and germplasm with disease and pest resistances, reduced sugar accumulation, reduced need for production inputs, and enhanced nutritional qualities. Targets for resistance breeding are the major diseases and pests affecting potato production in the western United States. Many of these diseases and pests are nationally important, with germplasm and varieties from our program also benefitting potato producers outside the western United States as well. Objective 1: Develop potato germplasm with beneficial traits and make available to the potato industry, breeders, and geneticists. Objective 2: Develop enhanced potato varieties that benefit U.S. potato producers and consumers, including russets (fresh market and processing), long whites (processing), round whites (chipping), and specialty (red-skinned and yellow-fleshed), with emphasis on disease and pest resistance, reduced sugar accumulation, reduced need for production inputs, and enhanced nutritional qualities. Objective 3: Develop marker-assisted selection (MAS) protocols for potato traits, with an emphasis on pathogen and pest resistances. Objective 4: Characterize foliar and tuber responses of potato varieties to infection by newly identified strains of potato virus Y (PVY), and identify new sources of resistances to these PVY strains useful to potato breeders.
1b. Approach (from AD-416)
This research, performed under institutional biosafety policies, will benefit the western U.S. potato industry by developing new potato varieties that will maintain the economic viability and competitiveness of this region in an age of expanding global competition. This will be accomplished by producing new potato varieties with improved agronomic characteristics, nutritional qualities, disease/pest resistances, and a reduced need for production inputs such as water and nitrogen. Desired traits will be acquired from wild relatives of the cultivated potato and from germplasm of other potato breeding programs within and outside of the U.S. Identified parental material will be hybridized with potato breeding clones and varieties adapted to the irrigated environments of the western U.S. Progeny of hybridizations will be evaluated, performance data collected, and superior individuals selected and advanced in the program for release as potato varieties with enhanced attributes. Newer technologies, such as marker-assisted selection, will be used to facilitate the development of enhanced potato varieties. Replacing 5366-21000-023-00D 01/2008
3. Progress Report
Five new potato varieties were developed and released with collaborators of the Northwest (Tri-State) Potato Variety Development Program: Classic Russet, Alpine Russet, Clearwater Russet, Owyhee Russet, and Red Sunset. All five varieties originated from this project’s hybridization program, with University of Idaho colleagues and this project leading in the release of Classic, Alpine, and Clearwater Russet. Classic Russet is notable for its use as an early harvest variety suitable for fresh-pack and processing. Alpine Russet is most notable for having a long tuber dormancy equivalent to that of Russet Burbank, the industry standard for long-term storage for processing; its processing characteristics from long-term storage are also superior to that of Russet Burbank. Clearwater Russet and Owyhee Russet are notable for their high percentage of U.S. No. 1 tubers relative to industry standards, their resistance to sugar accumulation during storage at low temperatures, and their attractive tuber type, making them suitable for use by both the processing and fresh-pack industries. Red Sunset is a red-skinned, white-fleshed variety notable for its high marketable yield and high vitamin C content. Both Clearwater and Classic Russet have higher concentrations of protein than varieties currently grown by industry, thereby improving potato’s contribution of protein to the U.S. diet. Additional research included fine-mapping of potato leafroll virus (PLRV) resistance from the potato wild species, Solanum etuberosum and publication of this research in a peer-reviewed, scientific journal in FY 2009. Resistance to PLRV, a primary virus pathogen of potato, has been shown by our program to be highly heritable across four generations of backcrossing to cultivated potato, making it useful for the genetic enhancement of potato. Evaluation of project germplasm for the presence of a potato virus Y (PVY) resistance gene (Ryadg) from Solanum tuberosum subsp. andigena also was vompleted. Research involved an assessment of PVY resistant breeding lines for the presence of three molecular markers linked to Ryadg and confirmation that their presence in a clone also was associated with resistance to multiple strains of PVY. Results showed that the presence of the three molecular markers was correlated with high levels of PVY resistance and a manuscript detailing this research is currently in press and available online. Use of the PLRV and PVY molecular markers in the breeding program has the potential to decrease the amount of time necessary to identify virus resistance in parents and progeny and therefore increase selection efficiency in the program. In addition, research was conducted and is ongoing to correlate pink rot and leak resistance in breeding clones with molecular markers. A three year survey for PVY in late generation seed lots in both the U.S. and Canada has now been completed. Tuber bioassay results from twelve varieties (nine released by this program and the University of Idaho) are being combined with molecular and tobacco bioassay results from other cooperators to provide an overall view of the PVY strain types and their diversity. Meetings and reports
1. Release of Potato Variety, Classic Russet The sector of the potato industry involved in the production and sale of potatoes for fresh consumption are in need of improved, early-maturing, varieties relative to the industry standard, Russet Norkotah. ARS scientists in Aberdeen, ID, developed a new potato variety, Classic Russet that is an earlier maturing variety with attractive tuber type, a low incidence of defects, and a high protein content relative to industry standard varieties. Classic Russet has comparable or higher yields of marketable tubers than Russet Norkotah and has been rated highly for its culinary attributes. In addition, unlike Russet Norkotah, it can be used as an early harvest variety by the processing industry. The release of Classic Russet provides the U.S. potato industry with an earlier-maturing variety useful for both fresh-pack and processing.
2. Release of Potato Variety, Alpine Russet Russet Burbank is an industry standard for the processing industry, primarily because its long tuber dormancy allows it to be stored for long periods following harvest and then processed into frozen potato products. ARS scientists in Aberdeen, ID, developed a new potato variety, Alpine Russet. This variety also displays the long tuber dormancy of Russet Burbank, but is higher yielding than Russet Burbank and has superior processing characteristics following long-term storage. Alpine Russet provides the U.S. potato processing industry with an improved alternative to the industry standard, Russet Burbank.
3. Release of Potato Variety, Clearwater Russet Improved potato varieties are important in maintaining the competiveness of the U.S. potato industry. ARS scientists in Aberdeen, ID, developed a new potato variety, Clearwater Russet that addresses this need with its high marketable yield, attractive tuber type, and excellent processing characteristics including resistance to sugar ends. This variety also has a higher protein content than standard russeted varieties currently by the U.S. industry. It’s attractive tuber type coupled with its processing characteristics makes Classic Russet a good dual-purpose variety for use by both the fresh-pack and processing sectors of the U.S. potato industry.
Kelley, K., Whitworth, J.L., Novy, R.G. 2009. Mapping of the potato leafroll virus resistance gene, Rlretb, from Solanum etuberosum identifies interchromosomal translocations among its E-genome chromosomes 4 and 9 relative to the A-genome of Solanum L. sect. Petota. 2009 Molecular Breeding 23:489-500.