Identification of resistance to barley leaf stripe using a Pyrenophora graminea transformant expressing beta-glucuronidase

A Pyrenophora graminea strain expressing the beta-glucuronidase gene (GUS) was obtained via genetic transformation, and used to follow the penetration of the pathogen inside barley germinating seeds and the colonization of ho st tissues. Significant differences between resistant and susceptible barle y cultivars were observed in the colonization of artificially-infected embr yos by the fungus. These results suggest that the GUS transgenic strain of P. graminea will be useful for the early screening of barley cultivars for resistance to leaf stripe disease.