Aflatoxin contamination of groundnut by Aspergillus flavus is a serious problem affecting the quality and
commercial value of groundnut kernels. Biological management of A. flavus infection at pre- and post-harvest levels
by using species of Trichoderma is a promising approach. Trichoderma isolates from the fields of Andhra Pradesh
and Karnataka states of India were evaluated for their ability to control A. flavus (strain Af 11-4) in the laboratory.
Out of 212 isolates of Trichoderma, 36 were potent antagonists and these were analyzed for the production of
volatile and diffusible antibiotics. Twenty-one of the 36 isolates produced volatile antibiotics and 15 produced
diffusible antibiotics. Biocontrol mechanism of their action was analyzed by estimating extracellular enzyme
production viz, chitinase, protease and glucanase. Maximum chitinase activity was associated with the isolate T.
viride (Tv 24), T. pseudokoningii (Tp 29) and T. harzianum (Th 42). T. harzianum showed a maximum protease
activity while T. koningii (Tk 83) and T. longibrachiatum (Tl 102) produced glucanases in the presence of glucose
