Applied and Environmental Microbiology (2005) 71, 6241-6246
Ada Viterbo, Michal Harel, Benjamin A. Horwitz, Ilan Chet and Prasun K. Mukherjee (2005)
Trichoderma mitogen-activated protein kinase signaling is involved in induction of plant systemic resistance
Applied and Environmental Microbiology 71 (10), 6241-6246
Abstract: The role of a mitogen-activated protein kinase (MAPK) TmkA in inducing systemic resistance in cucumber against the bacterial pathogen Pseudomonas syringae pv. lachrymans was investigated by using tmkA loss-of-function mutants of Trichoderma virens. In an assay where Trichoderma spores were germinated in proximity to cucumber roots, the mutants were able to colonize the plant roots as effectively as the wild-type strain but failed to induce full systemic resistance against the leaf pathogen. Interactions with the plant roots enhanced the level of tmkA transcript in T. virens and its homologue in Trichoderma asperellum. At the protein level, we could detect the activation of two forms reacting to the phospho-p44/42 MAPK antibody. Biocontrol experiments demonstrated that the tmkA mutants retain their biocontrol potential against Rhizoctonia solani in soil but are not effective against Sclerotium rolfsii in reducing disease incidence. Our results show that, unlike in many plant-pathogen interactions, Trichoderma TmkA MAPK is not involved in limited root colonization. Trichoderma, however, needs MAPK signaling in order to induce full systemic resistance in the plant.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
resistance/tolerance/defence of host
Research topic(s) for beneficials or antagonists:
molecular biology - genes
