Identification of slow stripe rusting wheat genotypes

Stripe or yellow rust is a constraint to wheat production on about 12.8 m ha in the Northern Hills and North Western regions of India. Varieties resistant at the time of release become susceptible usually within a few years due to new pathogen races. The present study conducted in 2013-14 was undertaken to identify slow stripe rusting genotypes among a panel of 192 advanced breeding lines and popular cultivars. All genotypes were planted in two replications and a susceptible control was planted after every 20 plots. The nursery, grown at Karnal, was inoculated with a mixture of prevalent Pst races 78S84 and 46S119. Genotypes were categorized into distinct groups based on area under disease progress curve (AUDPC) values, viz. 22 lines with AUDPC values 1-100, 18 lines with values 101-200, 43 lines with values 201-500, and remaining lines with higher values. Apart from rust-free lines assumed to carry all-stage resistance genes, lines with AUDPC values of less than 500 and having AUDPC values <20% of those of the susceptible check (maximum AUDPC value, 2500) were considered to be slow rusting. Some of the popular cultivars (HS 507, HS 542, WH 1105, HD 3086, DPW 621-50, HD 3059) currently grown in northern India showed slow rusting. The information generated can be utilized in improving the levels of stripe rust resistance in current cultivars.

Indian Institute of Wheat and Barley Research (IIWBR), India
Primary Author Email: