Effective genes for resistance to stripe rust and virulence of Puccinia striiformis f. sp. tritici in Pakistan
Virulence patterns of wheat stripe rust were studied under the field conditions across four environmentally different locations: Quaid-i-Azam University (Islamabad), Pirsabak (NWFP), Faisalabad (Punjab) and Sakrand (Sindh) by planting trap nursery of tester lines and Pakistan varieties. The results revealed that stripe rust resistance genes Yr3, Yr5, Yr10, Yr15, Yr26, YrSP and YrCV were resistant, while Yr18 showed moderate susceptibility at all locations. Genes YrA-, Yr2, Yr6, Yr7, Yr8, Yr9, Yr17, Yr27 and gene combinations Opata (Yr27+Yr18) and Super Kauz (Yr9, Yr27, Yr18) were found susceptible. Among the fifty-one (51) commercial varieties; Barani70, Marvi2000, Iqbal2000, GA2000 and Seher2006 were found resistant. The genes found effective against stripe rust under natural conditions may be deployed singly or in combination to develop high yielding resistant wheat varieties in Pakistan.
Key words: Near-isogenic lines, Puccinia striiformis f. sp. tritici, stripe rust, Triticum aestivum, virulence, Yr genes.