A study on the effect of different agrowastes on the population density and shelf life of Trichoderma harzianum indicated that all the substrates showed effective propagation of T harzianum; however, the population count after 30 days was maximum in used tea leaves (8 x 10(8) cfu/g) and shelf life was found to be maximum (2.9 x 10(5) cfu/g after 2 10 days) in wheat bran-sawdust. The application of these formulations on chickpea and groundnut plants significantly reduced the percent mortality due to chickpea wilt complex and groundnut collar rot disease, respectively. (c) 2006 Elsevier Ltd. All rights reserved.