Involvement of Epl-1 Protein in the Regulation of Virulence- and Tomato Defense-Related Genes.

Several spp. are well known for their ability to: (i) act as important biocontrol agents against phytopathogenic fungi; (ii) function as biofertilizers; (iii) increase the tolerance of plants to biotic and abiotic stresses; and (iv) induce plant defense responses via the production and secretion of elicitor molecules. In this study, we analyzed the gene-regulation effects of Epl-1 protein during the interactions of mutant Δ or wild-type strains with: (a) the phytopathogen and (b) with tomato plants, on short (24 h hydroponic cultures) and long periods (4-weeks old plants) after inoculation. Our results indicate that Epl-1 protein affects the expression of virulence genes, especially those involved in the botrydial biosynthesis ( genes), during the mycoparasitism interaction. The tomato defense-related genes were also affected, indicating that Epl-1 is involved in the elicitation of the salicylic acid pathway. Moreover, Epl-1 also regulates the priming effect in host tomato plants and contributes to enhance the interaction with the host tomato plant during the early stage of root colonization.