Effects of Common Pesticides Used in Rice Fields on the Conidial Germination of Several Isolates of Entomopathogenic Fungus, Beauveria bassiana (Balsamo) Vuilleminof Rafsanjan Region and Vicinity, South East Iran

Abstract

 The integration of biological and chemical control approaches is very important for a successful Integrated Pest Management (IPM) program. The entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (sensu lato) is one of the facultative insect pathogens with significant host range and host specificity. In this study, the effects of eight common pesticides used in rice fields were studied on the germination of B. bassiana. The experiments were carried out in the laboratory at 25±1°C, 80±5% RH and a 16h-photoperiod.The isolates Mcb 6, EUT 116, IRAN 429C and DEBI 005 of B. bassiana were treated with the field recommended rate of the pesticides. Experiments were performed according to the completely randomized design (CRD). The results showed that fungicides had the highest adverse effect on the germination of the isolates of B. bassiana. So it can be concluded that fungicides are limitation factors for activity of the fungus in the rice fields. The highest germination of fungal isolates was in the herbicide treatments, thus, they can be used in rice IPM programs.