Characterizing Late Blight Resistance of Parental Genotypes Used in the North Dakota State University Potato Breeding Program

Abstract

The potato is an important food crop, and late blight is a potato disease costing growers millions of dollars. Utilizing cultivars with late blight resistance is the longest-term option to manage the disease. This two-part study identified genetic resistance to late blight present in North Dakota State University potato germplasm. More than 750 families were screened using a multiyear detached leaf assay. ND8277B-5, Dakota Trailblazer, EB8109-1, ND028856B-1Russ, and Stirling, were found to be the most successful parents. Additionally, 236 clones were evaluated for six late blight resistance (R) genes: R1, R2, R3, RB, Rpi-smira1, and Rpi-ber1. At least one R gene was found in 136 clones. The R1 gene was most prevalent. R1, R2, R3, and RB genes were present in ND14358AB-1, while three R genes were present in Etb 5-31-3 and J101-K6. These evaluations can guide breeding efforts for R gene stacking, developing a durable resistance to late blight.