Detection of genetic variation among stripe rust ( Puccinia striiformis f. sp. tritici ) pathotypes of wheat with simple sequence repeat markers

Stripe or yellow rust disease of wheat caused by Puccinia striiformis Westend. f. sp. tritici Eriks., is very important disease worldwide. In India, the disease is very important in northern plains and hills. Microsatellite marker assay was used to amplify the DNA of five P. striiformis pathotypes, 7S0 (virulent on Yr1 , Yr6 , Yr7 ), 78S84 (virulent on Yr9, Yr27 ), 46S119 (virulent on Yr 9 ), 46S102 (virulent on variety Sonalika) and 47S102 (virulent on Yr1 ). Among 19 SSRs markers used, seven markers showed polymorphism among stripe rust pathotypes. Primer SUNIPst 9-48 amplified two bands (200 bp, 210 bp) with pathotypes, 7SO, 78S84, 47S102 and 46S102 but only one band (210 bp) with pathotype 46S119. Primer SUNIPst 10-06 resulted in amplification of 46S119 pathotype only. Primer SUNIPst 11-4 was monomorphic for pathotypes, 7S0 and 78S84 (only one band of same size produced) but differentiated these two pathotypes from rest of three pathotypes, 46S119, 47S102 and 46S102. Primer SUNIPst 16-10 was monomorphic for pathotypes, 7S0, 78S84 and 46S119 but differentiated these pathotypes from pathotypes, 47S102 and 46S102. Present study revealed genetic variation in five Indian P. striiformis pathotypes 7SO, 78S84, 47S102, 46S102 and 46S119. Use of DNA fingerprinting of stripe rust pathotypes with reliable markers will help in efficient and rapid identification of new pathotype.