Inorganic Amendments for Enhancement of Biocontrol Efficiency of Trichoderma harzianum Against Pythium Damping-off of Tomato

Efficacy of some inorganic salts- sodium bi-carbonate, calcium carbonate, zinc sulphate, magnesium sulphate and di- potassium hydrogen phosphate, and starch, for enhancing growth and biocontrol efficiency of a local strain of Trichoderma harzianum was tested. Magnesium sulphate, di-potassium hydrogen phosphate and zinc sulphate found promising in vitro were evaluated in pots having soil inoculated with Pythium aphanidermatum. Talc based formulation of T. harzianum amended with the individual salt @ 0.5% w/w as seed treatment @ 5, 7.5 and 10g/kg seed resulted in increased biocontrol efficiency of T. harzianum against Pythium damping -off in tomato cv. Navodaya. Best effect in terms of significantly lower mortality of tomato plants and higher germination, dry biomass, and population density of T. harzianum in rhizosphere was observed with magnesium sulphate, followed by dipotassium hydrogen phosphate and zinc sulphate@ 10 g/kg seed.