Growth, esporulation and viability of entomopathogenic fungi under mediums with differents Nim oil (Azadirachta indica) concentrations

摘要

> face="Verdana, Arial, Helvetica, sans-serif" size="2">The association of vegetable extracts with entomopathogenic fungi can increase the efficiency of biological control of pests, to reduce costs and environmental impacts. The present work aimed to evaluate, through minimal inibitory concentration, the effect of the neem oil (NIM-I-GO) on the growth, esporulation and viability of Metarhizium anisopliae, Beauveria bassiana and Paecilomyces farinosus. For this purpose the PDA medium was used containing different concentrations of neem oil (C1: 5% of neem oil, and successively concentrations ½ of the previous concentration, until the concentration C11:0,0048% of neen oil). The neen oil reduced the growth of B. bassiana and P. farinosus, which didn’t differ significantly of the control at the concentration C11. Similar effect was observed for M. anisopliae with 0,039% of neem oil (C8). The esporulation was also significantly reduced by the neem oil, except at the concentration C11 for B. bassiana; however, no oil effect was observed on the viability of the fungi spores.