Location: Temperate Tree Fruit and Vegetable Research
2017 Annual Report
Objectives
Determine the value of advanced potato germplasm with particular attention to
disease, pest, and stress resistance, yield, quality characteristics, and
profitability parameters. Define cultural conditions which will optimize yield and quality of each clone.
Approach
New germplasm arising out of Federal and State breeding programs will be propagated to produce relatively disease-free seed. Clones will be grown under several climatic conditions, in multiple locations, under a multitude of cultural practice variables,and under planned disease, pest, and stress exposures. Evaluations will include expressions of resistance, yield, quality (external and internal), processabililty,storability, phytonutrient content and overall assessment of profitability under existing pricing and contracts for raw product in the fresh and processed sectors. Attention will be placed on developing an array of potential cultivars with candidates for every market type on a national and international basis. Larger scale commercial trials of more promising clones will be organized with industry representatives.
Progress Report
A total of 99,400 single hills (1st field generation clones) and 1,400, 12-hill (2nd field generation) selections were planted, maintained, and harvested at three seed sites in Idaho. Advanced breeding clones were evaluated in 32 replicated field trials in six locations across southern Idaho for their potential as new potato varieties. Twenty-two entries from the Aberdeen program were entered in advanced agronomic and processing trials in the Tri-State and Western regions to assess their performance relative to industry standards. In addition, 12 field studies were completed in 2016 to develop management guidelines for new varieties. These studies addressed nitrogen fertilizer requirements, optimal plant spacing and seed piece size, irrigation management and water stress responses, herbicide tolerances and storage management requirements. Management guidelines for new cultivars were published on the University of Idaho Potato Center and the Potato Variety Management Institute (PVMI) websites (www.cals.uidaho.edu/potato; www.pvmi.org).
Progress has continued in identifying corky ringspot resistant germplasm that also has desirable yield, quality and tuber appearance characteristics. In addition, the breeding program is progressing in the evaluation and identification of germplasm with genetic resistances to potato viruses X and Y (PVX, PVY), potato leafroll virus (PLRV), foliar and tuber late blight, nematodes, potato mop-top virus (PMTV), zebra chip, and potato psyllid (insect vector for Liberibacter responsible for zebra chip). Research detailing resistance to potato psyllid and possible resistance to Liberibacter in germplasm from the Aberdeen breeding program was published, and a late blight resistant potato cultivar, Payette Russet, was released. Payette Russet is product of breeding efforts for enhanced virus resistance as it has extreme resistance to PVY.
Nitrogen (N) is the most important yield-related component of potato nutrition. In-season N rates were identified to maximize grower revenue by optimizing field performance and post-harvest quality attributes. In-season N affects whole plant morphology and physiology therefore this information is critical to best management practices and for growing potatoes profitably. Four rates of in-season N were applied to Clearwater Russet, GemStar R., Mountain Gem R. POR06V12-3, Targhee Russet, A03921-2, A06084-1TE, and Payette Russet with 0.15 inch of water via a fertigation simulator. The rates were based on what might be typical for a Russet Burbank crop. All treatments received the same pre-plant fertilizer during a particular year. All nutrients, other than N, were non-limiting and were the same across all treatments and varieties. Petiole and soil data demonstrated treatment differences. Yield and economic values varied across varieties. Columbia Basin growers were advised to use 300-325 pounds (lbs) per acre (A) N per year for Mountain Gem Russet, A03921-2, and A06084-1TE; 350-375 lbs/A for Clearwater R., POR06V12-3, and Targhee R.; and 375-400 lbs/A for GemStar R. and Payette R. It is has been recommended that growers should be careful when experimenting with large reductions of N to seek cost savings. Cutting N in half may cut total yield in half, resulting in a production disaster. Growers should not cut N, even on new more N efficient varieties. Although Alturas requires 30 to 40 percent less N than Russet Burbank, the N savings with other new varieties is much less (15-25%). Reduction in the application of N carries a profitability loss that may be unacceptable to growers.
In the Columbia Basin, potato growers often apply some or all of their phosphorus (P) at time of planting. Many growers also supplement pre-emergent applications with in-season applications of ammonium polyphosphate through irrigation water (fertigated). The industry wanted to know the effect of P fertigation on soil P, petiole P, and plant production. To do this, researchers applied 227 or 454 lbs/A of phosphorus pentoxide (P2O5) at planting, in-season through fertigation, or half at planting and half in-season. The control was untreated. The potato variety tested was Umatilla Russet. All nutrients other than P were non-limiting and equally applied to the test samples. Results showed no significant differences among the treatments and the non-treated control for gross return, or any other production parameters. The soil pH was high (greater than 7.0), and the applied P may have been tied up through chemical reactions. However, differences in the effect of P applications were occasionally detected in soil and petiole analyses.
Commercially available P formulations (AVAIL, Accomplish, MESZ) were tested to identify products that allow us to use lower rates of fertilizer to reduce or prevent any possible ground water P contamination. P Fertilizer was applied during planting in a liquid band 1-2 inches above the seed piece and to the side of the seed piece. The P fertilizer was in the form of 10-34-0 (114-, 227-, and 454-lbs P2O5), MESZ (114- and 227-lbs/A P2O5), Accomplish (114- and 227-lbs/A P2O5), and AVAIL (114- and 227-lbs/A P2O5) and applied to P deficient soils (less than 14 parts per million [ppm] P) with a high pH (more than 7.0). Treatments were applied to potato variety Umatilla. All nutrients other than P were non-limiting and the same across treatments. Due to high variability in the poor soils selected for these trials (low P, high pH), within and across years, statistical differences were not seen for yield or economic return. None of the treatments produced higher yields than the non-treated control. Because of the variability it was not possible to determine whether the use of these products provided a significant advantage over the control.
The Oregon State University (OSU) group conducted 36 field trials in 4 regions, Hermiston, Klamath Falls, Ontario and Corvallis. A total of 58,000 seedling tubers were planted at the Klamath Basin Research and Extension Center with 2 percent retained for further evaluation. In addition, 4,000 seedling tubers segregating for PVY resistance were planted at Hermiston Agricultural Research and Extension Center (HAREC) with 4.8 percent retained for further evaluation. At Hermiston and Klamath Falls, 909 4-hill, 2nd field generation selections were planted: 77 percent russets, 8 percent fresh market specialty types, 10 percent chipping, and 5 percent PVY resistant; and 116 retained for further evaluation. At Hermiston, Klamath Falls, and Ontario 36 20-hill selections, 3rd field generation, were evaluated in two-replicate trials with 10 retained for further evaluation. Approximately 75,000 seedling tubers were generated in Corvallis greenhouses with approximately 70 percent true potato seed derived from ARS Aberdeen, Idaho, crosses and the remainder originating from ARS Prosser, Washington, and OSU. The largest seedling tuber (A-size) from each family was reserved for single-hill planting at Klamath Falls. Disease, pest, and abiotic stress resistance trials were completed at Corvallis and Hermiston. As part of the National Chip Processing Trials, three additional field trials were established at HAREC and OSU to evaluate chipping clones for the Columbia Basin. More than 40,000 pounds of breeder seed from the Tri-State program was produced and shipped to trial coordinators for 2016 planting. Initial screening for new sources of resistance to soil borne pathogens Columbia Root-Knot Nematode (CRKN) and Verticillium wilt (VW) found Solanum hougasii and S. iopetalum conferred resistance CRKN and VW, respectively. Replicated screening trials are underway to confirm these potential new sources of resistance.
As part of the Tri-States variety development program, Oregon led the release of two clones in 2017. Smilin’ Eyes (POR02PG26-5)is an early specialty potato with yellow skin, red eyes and yellow flesh. This selection is unique among commercially available varieties for its bright red eyes and high culinary quality. Tubers are ideal for microwaving, frying, or baking. Fry color is light and uniform. TerraRosa (POR02PG20-12) is a mid-season specialty potato with red skin and red flesh. This selection is unique among commercially available potato varieties because plants set a large number of smooth, small, and oblong to long-shaped tubers with red skin and red flesh. Plant Variety Protection (PVP) applications for Smilin’ Eyes and TerraRosa were submitted to the PVP office.
In addition, Oregon submitted two russet selections, AO96141-3 as Echo Russet and POR06V12-3 as Castle Russet, for approval for release as new varieties to the OSU variety release committee.
Accomplishments
1. Smilin’ Eyes (POR02PG26-5) potatoes provide a new option to fresh market growers. Smilin’ Eyes is an early maturing variety with red pigment around the eyes and brighter yellow flesh than Yukon Gold. This variety was identified with contributions from ARS scientists at Wapato, Washington, and scientists from Washington State University, University of Idaho, and Oregon State University. This selection is unique among commercially available varieties for its high culinary quality from microwave, frying or baking. Its total yield is higher than that of Yukon Gold, and it is prized for a much greater proportion of the yield found in the 4 to 6 ounce size range. Smilin’ Eyes will provide a new market option in the largest specialty potato market niche (PVP201700060).
2. TerraRosa (POR02PG20-12) is a solidly red-fleshed new variety. TerraRosa is a mid-season specialty potato with red skin and flesh. It was developed with contributions from ARS scientists in Wapato, Washington, scientists at Oregon State University, Washington State University, and the University of Idaho. This selection is unique among commercially available potato varieties in that plants set a large number of smooth, small, oblong to long shaped tubers with red skin and flesh. Tubers are good for boiling, baking, and microwaving. Potato chips made from TerraRosa tubers retain their red color and have very good taste. This variety is a good candidate for the organic sector due to its resistance to common scab and golden cyst nematodes (PVP201700061).
Review Publications
Yilma, S., Charlton, B.A., Shock, C.C., Hane, D.C., James, S.R., Mosley, A.R., Rykbost, K.A., Fiebert, E.G., Knowles, R., Pavek, M.J., Stark, J.C., Novy, R.G., Whitworth, J.L., Pavek, J.J., Corsini, D.L., Brandt, T.L., Olsen, N., Brown, C.R., Vales, I., Sathuvalli, V. 2017. Sage Russet: A new high yielding dual-purpose russet variety, with cold-sweetening resistance, high vitamin C and protein contents and excellent fresh pack and processing potential. American Journal of Potato Research. 94(4):379-389.
Sathuvalli, V., Brown, C.R., Yilma, S., Charlton, B.A., Shock, C., Quick, R.A., Feibert, E., Whitworth, J.L., Novy, R.G., Stark, J.C., Pavek, M., Knowles, R., Navarre, D.A., Vales, I. 2016. Yukon Nugget: a mid-season yellow skin, yellow flesh specialty potato with extreme resistance to potato virus X. American Journal of Potato Research. 93(6):602-608.
