Evaluation of agro-industrial wastes for conidia based inoculum production of bio-control agent:: Trichoderma harzianum

For management of agro-industrial wastes and selection of a suitable cheaper substrate for bio-pesticide development, three categories of agro-industrial wastes, viz. (i) Cellulosic wastes, (ii) Organic manures, and (iii) Cereal brans are evaluated for growth responses and conidial yield of the bio-control agent Trichoderma harzianum. All the substrates support fairly good growth and sporulation of the bioagent, but conidial counts are maximum in rice bran in 15 d followed by paddy straw and wheat straw in 20 d. Supplementation of all the substrates with chickpea flour as organic nitrogen supplement enhances the conidial yield, maximum increase in spore count being recorded in the case of paper waste. The optimum level of chickpea flour supplementation for paper waste is recorded as 12 per cent (w/w), thereby showing maximum conidiospore production (17.07x10(8) cfu/g) in 20 d, a further increment in cfu count is recorded upon its supplementation with rice bran. Paper waste based mixed substrate combination containing paper waste (80 per cent), rice bran (8 per cent) and chickpea flour (12 per cent) shows considerably higher conidial yield (11.73x10(9) cfu/g) after 10 d incubation period, exploring the possibility of utilizing it for mass multiplication and large-scale inoculum production of ecofriendly bio-control agent for sustainable environment.