Screening of wheat germplasm against stripe rust disease under field conditions in Pakistan

Abstract

Rust in wheat is a serious threat worldwide and causes a significant loss in yield that may be more than 90% in case of susceptible variety or under epidemic conditions. Among different rusts of wheat, Stripe rust (Puccinia striiformis f. sp. tritici) poses a serious threat to wheat production in cooler areas of Pakistan. The 70% area of wheat in Pakistan is prone to stripe rust. Enduring resistance based on partial resistance is very noteworthy and successful way to combat stripe rust dilemma in wheat crop. For this purpose, one hundred and forty nine wheat varieties/lines were screened, and severity of stripe rust was recorded. One row Morocco of which is universally susceptible to wheat rusts was planted around the nursery. Inoculum in the form of uredial suspension was sprayed uniformly with a sprayer with a fine nozzle. Data were recorded in the month of April/May when the universally susceptible wheat variety Morocco developed up to 80% severity. According to results, 60 lines/varieties were found immune against all the races of yellow rust prevailing in nature. Twenty lines showed the symptoms of resistant as chlorosis was observed without uredia. Similarly, 12 lines were moderately resistant and 35 lines were in the range of resistant to moderately resistant. Ten lines/varieties were found moderately susceptible while 5 lines/varieties showed the symptoms of susceptible. Our results indicated that a large number of varieties have high level of resistance and can be used against wheat stripe rust