Multiple resistance sources to yellow rust and powderymildew in some exotic wheats

摘要

Among various diseases, yellow rust (Puccinia striiformis f. sp.fr/ftc/) and powdery mildew (Blumeria graminis tritici) inflict huge yield losses in North Hill Zone (NHZ) and North Western Plain Zone (NWPZ) of the country. Cultivation of resistant varieties is a practically feasible, eco-friendly and environmentally viable means to manage these diseases. However, evolution of new and matching virulence render such resistant varieties susceptible necessitating breeding for resistance against these diseases a continuous process utilizing the stable resistant donors of diverse origin. In this context, 410 genotypes comprising advanced breeding material of 17"' Spring Bread Wheat Yield Trial-Heat Tolerant (17,h SBWYT HT), 17,h Drought Screening Bread Wheat Observation Nursery (17,h DSBW-ON) and Spring Wheat Yield Trial Observation Nursery (17th SWYT-ON) were evaluated against yellow rust (YR) and powdery mildew (PM) at CSKHPKV, RWRC, Malan during 2016-17 and 2017-18. Eighteen genotypes from 17,h SBWYTHT, twenty five genotypes from 17th DSBW-ON and thirty five genotypes froml7,h SBWON-HT material showed multiple field resistance to YR and PM. Agronomically superior entries may be utilized as varieties and/or as donors in breeding program. In NHZ wheremore than 80 area is rainfed and in NWPZ where terminal heat is emerging as a potential threat, the YR and PM resistant donors with additional attributes of heat and drought tolerance in nurseries, involving heat tolerant and drought tolerant materialmay utilized in the breeding programs to evolve varieties with multiple biotic and abiotic resistance.