ARS | Publication request: Identification of potato breeding clones that confer high levels of late blight resistance to their progeny

Submitted to: American Journal of Potato Research
Publication Type: Abstract Only
Publication Acceptance Date: March 15, 2006
Publication Date: January 1, 2007
Repository URL: http://riley.nal.usda.gov/nal_web/digi/submission.html
Citation: Whitworth, J.L., Novy R.G., Lozoya-Saldana H., Yilma S., Mosley, A.R. and Vales I.M.. Identification of potato breeding clones conferring high levels of late blight resistance to their progeny in Toluca Valley, Mexico. Amer. J. Potato Res 84:120 (Abstract)

Technical Abstract: Since 1996, potato seedling minitubers derived from greenhouse crosses have been grown out under heavy late blight pressure in Toluca, Mexico. A total of 2500 individuals were planted each year along with cv. Alpha as a susceptible control. Percent defoliation readings were taken on a weekly basis until early September each year. The number of resistant x susceptible (RxS) and resistant x resistant (RxR) crosses were calculated each year and comparisons on the amount of resistant individuals and families were made across the years. In addition, selection for agronomic type was conducted in the same year by planting a replicate of each individual in Aberdeen, Idaho. At harvest, late blight data collected from Toluca was used to select from these individuals with good agronomics and late blight resistance. Individuals selected at Aberdeen were then screened for tuber resistance at Corvallis, OR. Analysis shows that RxR crosses increase the percentage of resistant individuals, demonstrating that combining resistance from both parents allows for increased selection of resistant types. Parents are identified that give good resistance in RxS and RxS crosses.