Location: Emerging Pests and Pathogens Research2011 Annual Report
1a. Objectives (from AD-416)
The objectives of this cooperative research project are to develop and release improved potato cultivars with resistance to multiple races of the golden nematode, effect more efficient protocols to screen segregating potato populations for resistance to the golden nematode, develop profiles of new resistant cultivars to aid grower acceptance, provide for nuclear disease-free seed of resistant cultivars.
1b. Approach (from AD-416)
1) Crosses of potato clones will be made to generate populations that are segregating for resistance to multiple races of the golden nematode and improved horticultural and marketing characteristics. 2) Potato clones will be evaluated for nematode resistance. 3) Resistant potato clones will be subjected to an extensive evaluation scheme and selected for improved yield, desired marketing characteristics, and disease resistance. 4) Production and storage profiles for advanced clones will be developed through field testing. 5) Disease-free seed stocks will be maintained and multiplied as necessary to meet grower demands.
3. Progress Report
The overall objective is to develop and release new potato varieties resistant to both races of the golden potato cyst nematode (GN). In 2010, we produced over 150,000 seeds (M generation) of 71 progenies. All of the crosses segregate for resistance to Ro1 or Ro2. We transplanted 27,500 seedlings (L generation) into 72 hole seedling trays for hardening in the greenhouse, then to six inch pots in outdoor beds. Among the 21,028 saved clones, all segregate for resistance to Ro1, while 13% segregate for resistance to Ro2. We also planted approximately 10,000 clones at the 4-hill plots stage (K generation) and saved 1,241 clones. We planted 1862 white clones and 50 colored clones at the 20-hill plots stage (J generation). All clones segregate for resistance to Ro1 and/or Ro2. Two hundred and sixty-five clones were saved after postharvest analyses. The 117 clones at the 100-hill plots stage (H generation) were also planted in 2 x 15 foot observation plots and 16 clones with resistance to Ro1 were saved. Twenty-two clones (G generation) were planted in replicated trials at two locations and unreplicated observation plots at an additional three locations. Eight clones survived post-harvest selection based on yield, appearance, and specific gravity. In addition, we tested 21 advanced round white and 3 round red clones (F, E, D, NY generations) at three locations around Ithaca and also distributed seed for several other trials. One of the white clones (NY140) was found to be resistant to GN Ro2. We continued to screen potato clones and varieties for GN resistance. A total of 732 and 109 clones were evaluated for Ro1 and Ro2 resistance, respectively. Among these, five hundred and twenty-five clones were identified to be resistant to Ro1 and five clones were resistant to Ro2. We also identified that Sassy, an existing potato variety, is resistant to both GN Ro1 and Ro2. Extension potato variety yield trials were conducted with growers in upstate New York. Marketable yield, tuber quality and appearance, maturity, storage life and processing potential are among the important characteristics that were evaluated. We continued to produce Foundation seed of advanced GN-resistant potato clones and varieties. In the 2010 growing season, approximately 60% of the acreage at the Uihlein Farm was planted to 29 GN resistant varieties. The total estimated cwt (hundredweight) of GN resistant varieties sold and/or distributed was 4,838 cwt. The most significant accomplishment from this project was the release of three new GN resistant potato varieties Red Maria, Waneta, and Lamoka. Red Maria, formerly NY129, was released in early 2010. Red Maria is the first GN-resistant red variety developed by our program. Waneta and Lamoka, formerly NY138 and NY139, respectively, are all chipping varieties that were released in 2011. Research progress was monitored through email and phone conversations, meetings, and annual reports to USDA-ARS.