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

BMC Plant Biology

Research Article

Rhoda Delventhal¹  Ulrich Schaffrath¹  Sylvia Ulferts¹  Richard Splivallo²  Petr Karlovsky³ 

[1] Department of Plant Physiology, RWTH Aachen University, 52056, Aachen, Germany;Institute for Molecular Biosciences, Goethe University of Frankfurt, 60438, Frankfurt am Main, Germany;Molecular Phytopathology and Mycotoxin Research, University of Goettingen, Grisebachstrasse 6, 37077, Goettingen, Germany;

关键词: Penetration resistance;    Rice blast;    Head blast;    Quantitative microscopy;    Biotic stress;   

DOI  :  10.1186/s12870-014-0409-x

 received in 2014-10-16, accepted in 2014-12-29,  发布年份 2015

来源: Springer

【 摘 要 】

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

【 授权许可】

Unknown   
© Ulferts et al.; licensee BioMed Central. 2015. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.