Abscisic acid negatively interferes with basal defence of barley against Magnaporthe oryzae

摘要: Plant hormones are well known regulators which balance plant responses to abiotic and biotic stresses. We investigated the role of abscisic acid (ABA) in resistance barley (Hordeum vulgare L.) against pathogenic fungus Magnaporthe oryzae. Exogenous application ABA prior inoculation with M. oryzae led more disease symptoms on leaves. This result contrasted finding that enhances powdery mildew fungus. Microscopic analysis identified diminished penetration as cause for enhanced susceptibility. Consistently, mutant Az34, impaired biosynthesis, was less susceptible infection by displayed elevated compared isogenic wild type cultivar Steptoe. Chemical complementation Az34 plants exogenous re-established severity level. The susceptibility corroborated showing increased all cultivars under investigation except most Pallas. Interestingly, endogenous concentrations did not significantly change after Our results revealed levels a higher leaves supports earlier reports enhancing rice same pathogen thereby demonstrates host plant-independent function this phytohormone pathogenicity monocotyledonous