Efect of pH on Growth, Spore Production and Spore Viability of Biocontrol Agent Trichoderma Harzianum in Submerger Fermentation

The effect of pH medium on growth, spore production and spore viability of bicontrol agent Trichoderma harzianum were investigated in a batch farmenter in the range of 4 to 7. The biomass concentration of this fungus at pH 4,6 and uncontrolled pH were higher than at pH 5 and 7 after 18h incubation. The spore produced by the fungus at 6,7 and uncotrolled pH was higher than others. the highest level of spore production (6.67x107 spores/ml) occured at unctrolled pH, but the spore produced in the culture grown at 7 has a higher viability (52,5%) compared to those grown at other pH.