فریبا سهرابی

Metarhizium anisopliae is considered as one of the most important entomopathogenic fungi that can be used for biological control of stored product pests. In this study, M. asisopliae isolate Iran 1018C was used against fourth instar larvae and adults of Carpophilus hemipterus (Linnaeus). Bioassay method for larvae was performed with filter paper impregnated with spore suspensions in sterile Petri dishes and for adults by immersing insects in spore suspension. Spore suspension to concentrations of 3×108, 3×107, 3×106, 3×105 conidia/ml was prepared in Tween 0.02% and mortality of larvae was examined after 3, 7 and 9 days and for adults after 3, 7 , 9, 11, 13 and 15 days. Experiments were done in three replicates; each consisted of 10 larvae or adults, at 25 ? C under dark conditions. The results revealed that mortality percentage increased by increasing time and spore suspension concentration. Mortality rates of larvae for abovementioned concentrations were 78.9, 75.6, 73.3 and 54.4% and for adults were 51.7, 20.6, 12.2 and 10%, respectively. On the other hand results showed that the fungus at a concentration of 3×108 after 15 days and at a concentration of 3×105 after seven days caused the highest mortality rate of adults (63.3%) and larvae (97%), respectively. Results suggest that considering the insecticidal ability of isolate Iran 1018C against larvae and adults of date sap beetle, this fungus can be used as part of integrated control program of the pest.