Trichoderma induce Alteration of Serine/threonine and Tyrosine Phosphatase in Bipartite Interaction of Brassica juncea

Brassica are important edible oil crops of northern hemisphere of India and the major yield losses are due to the fungal pathogens. Biocontrol agent such as Trichoderma, enhances water micronutrient availability of the plants and induces systemic resistances against fungal pathogens by MAPK cascade. Dephosphorylation through tyrosine and serine/threonine phosphatase plays an important role in regulation of MAPK activity. To study tyrosine and serine/threonine phosphatase, Brassica seeds were mixed with slurry of Trichoderma strains and sown in conical flasks. One and two week later protein was isolated from seedlings. MyBP was labeled with radioactive phosphorus through (ã33P)-ATP at ser/thr position by PKA and at tyr position by Abl kinase which were used as substrate for the protein extracted from one and two week old Trichoderma inoculated seedlings. Ser/thr and tyrosine phosphatase removes inorganic 33PO₄ from the respective 33P-MyBP. Phosphatase activity were measured in terms of amount of free 33PO₄ in scintillation counter. It was found that the phosphatase activity in control plants were significantly higher as compared to treated plants showing the activation of respective kinases. Out of the two strain of Trichoderma harzianum, T43 is more potent than the T39 which may be able to provide added benefit to plants in longer duration of cultivation.