A new variant 5R9-7 of Puccinia triticina on emmer and durum wheats in India

Emmer and durum wheats are generally resistant to leaf (brown) rust in many countries including India, where pathotypes specialized to these wheats rarely occur. During 2006, widespread prevalence of leaf (brown) rust was recorded on Emmer wheat. A new pathotype, 5R9-7(DBBGB), of Puccinia triticina was associated with leaf rust on many of the popular cultivars, which was avirulent to most of the bread wheat accessions tested; including Agra Local, a susceptible host to wheat rusts in India. Pathotype 5R9-7(DBBGB) was found to be virulent to Lr2c, Lr14a, Lr18 and Lr20. Resistance sources to this pathotype based on evaluation of Indian and exotic wheat germplasm, its avirulence/virulence structure, adult plant response of important tetraploid wheat material and other attributes are described.