Potential Use of Beauveria bassiana (Balsamo) Vuillemin in biological control of Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae)

The use of entomopathogenic fungi as biological control agents against storage pests has become an effective method to reduce postharvest losses. This study aimed to determine the insecticidal effect of Beauveria bassiana, an important entomopathogenic fungus, on Sitophilus zeamais adults, known as the most important storage pest in maize. B. bassiana (ET 10) isolate prepared in three different spore suspensions (106, 107 and 108 conidia/ml + Tween 80 (0.02%)) was applied to S. zeamais adults by the spraying method. The experiment was set up in three replicates according to the randomized plot design. For each suspension, one experimental group was set with corn grains and 10 adult S. zeamais adults and the number of dead insects was recorded every 24 hours and the data was recorded until the conclusion 264 hours. As a result of the application, mortality were observed in all suspensions from the first 24 hours, reaching 100% in the 108 conidia/ml suspension at the 144th hour. At the end of 264 hours, the mortality rates were recorded as 26.7% for 106 conidia/ml, 36.7% for 107 conidia/ml, 100% for 108 conidia/ml. The most effective dose among the application suspensions was determined to be 108 conidia/ml. It has been proven that B. bassiana ET 10 isolate can be used as a potential bioagent as an alternative in the biological control of S. zeamais and that biological control with entomopathogenic fungi can be a correct and positive strategy.