Identification and characterisation of barley (Hordeum vulgare) respiratory burst oxidase homologue family members.

Respiratory burst oxidase homologues (RBOHs) of the human phagocyte gp91 gene have been isolated from several plant species and the proteins that they encode have been shown to play important roles in the cellular response to biotic stress via the production of superoxide. In this study we have identified and preliminarily characterised six RBOHs from barley (Hordeum vulgare L.).

Differential defense reactions in leaf tissues of barley in response to infection by Rhynchosporium secalis and to treatment with a fungal avirulence gene product.

Expression of defense-associated genes was analyzed in leaf tissues of near-isogenic resistant and susceptible barley cultivars upon infection by Rhynchosporium secalis. The genes encoding pathogenesis-related (PR) proteins PR-1, PR-5, and PR-9 are specifically expressed in the mesophyll of resistant plants, whereas a germin-like protein (OxOLP) is synthesized in the epidermis irrespective of the resistance genotype. Restriction-mediated differential display was employed to identify additional epidermis-specific genes.