Thursday 26 October 2017
Interplay between plant immunity, microbes and environment in Arabidopsis thaliana
(Nara Institute of Science and Technology Ikoma, 630-0192 JAPAN)
Plants often exploit plant-associated beneficial microbes for their adaptation to adverse conditions such as nutrient deficiency or high salinity, while retaining effective resistance against pathogens. This predicts that plants modulate immune responses according to the nature of their encountered microbes and environmental conditions at their habitats. The endophytic fungus Colletotrichum tofieldiae (Ct) colonizes the roots of Arabidopsis thaliana without visible disease symptoms, and promotes plant growth under inorganic phosphate (Pi)-limiting conditions, while in contrast its pathogenic relative, C. incanum (Ci), causes severe disease. These closely related fungi provides an excellent model to address the aforementioned hypothesis in the reference plant that is devoid of both mycorrhizal and nodule symbioses. I will report that host defences based on tryptophan-derived secondary metabolites, including the anti-fungal compounds indole glucosinolates, are required for both beneficial Ct association and effective Ci resistance. However, separate genetic requirements exist between the host control of Ct and Ci for Pi starvation response (PSR) and an endogenous peptide-based defence system. Furthermore, I would also like to report another study that microbial pattern recognition leads to salt tolerance, in addition to defence activation, in A. thaliana.
Contact : Lionel Verdoucq : firstname.lastname@example.org