Characterization of Biocontrol Agents Isolated From Temperate Region of India

Trichoderma species are potential fungal bio-control agents used against a wide range of soil borne plant pathogens. In the present study a total of 20 Trichoderma isolates viz., AT1, AT2, AT3, AT4, AT5, AT6, AT7, BT1, BT2, BT3, BT4, BT5, BT6, BT7, BT8, BT9, BT10, BT11, BT12, BT13 were isolated from vegetable fields of Kashmir valley and their efficacy was tested by using various biochemical tests. Thirteen isolates of Trichoderma viz., AT1, AT2, AT3, AT4, AT5, AT6, AT7, BT1, BT7, BT8, BT10, BT11 and BT12 were found to be positive for ammonia production. Similarly twelve isolates viz., AT2, AT3, AT7, BT1, BT3, BT4, BT7, BT8, BT10, BT11, BT12 and BT13 were found to be positive as far as the chitinase activity is concerned. In the IAA production assay maximum IAA was produced by isolate BT9 (6.605 μg mL-1) followed by BT6 (5.278 μg mL-1), while minimum IAA was produced by isolate AT1 (1.538 ìg mL-1). Only five isolates viz., AT1, AT2, AT3, AT4 and AT5 metabolized lactose and sucrose while seven isolates viz., AT1, AT2, AT3, AT4, AT5, AT6 and AT7 were found to metabolize maltose. Hydrocyanic acid (HCN) was observed to be produced by only three isolates of Trichoderma viz., AT3, AT5 and AT7. Trichoderma isolate AT3 qualifying most of the biochemical tests were morphological characterized as Trichoderma harzianum.