Abstract
Piriformospora indica is an endophytic fungus of the heterobasidiomycetous Sebacinales colonizing roots of different plant species. We investigated the interaction of P. indica with Barley (Hordeum vulgare) roots with respect to growth and pathogen resistance of the plants. P. indica infestation of the roots increases fresh weight of barley plants up to 60% and enhances resistance of the leaves against the biotrophic barley powdery mildew fungus Blumeria graminis f.sp. hordei. As a first step towards elucidating the mechanism of resistance induction, we checked mRNA levels of pathogenesis-related and hormone-induced genes in leaves of P. indica infested barley plants. Interestingly, mRNA of both jasmonic acid and salicylic acid induced genes, JIP-23 and PR-5, were not elevated in leaves of P. indica infested plants without challenge, indicating a possible involvement of new resistance signaling mechanisms.
