Pathogenesis-related genes responses in barley plants challenged with pathogenic fungi with different lifestyles

Abstract

Barley plants can be infected by a variety of fungal pathogens with different lifestyles. The biotrophic Blumeria graminis, necrotrophic Pyrenopora teres, and hemibiotrophic Cochliobolus sativus are economically important pathogens of barley worldwide. Currently, the mechanisms underlying resistance to these diseases are still largely unknown. In the current study, expression patterns of some well-known pathogenesis-related (PR) genes were monitored at early points of infection in resistant and susceptible barley genotypes using quantitative PCR method. Data showed earlier and higher accumulation of PR transcripts in the resistant genotype as compared with the susceptible one, and the expression patterns of the same defense-associated genes were altered in adaptation to each pathogen. The most outstanding differences were observed in PR1 and PR5 genes that were highly activated in resistant plants infected with the hemibiotrophic pathogen rather than the biotrophic and necrotrophic ones. The barley defense response mechanisms against these pathogens could be in agreement with the well-accepted concept that these events are intense in the resistant cultivar. This work might provide useful information for a deeper molecular research on barley defense responses toward pathogens with different lifestyles.