The effect of two isolates of Beauveria bassiana (Bals.) Vull. on the larvae of confused flour beetle [Tribolium confusum du Val., 1863 (Coleoptera: Tenebrionidae)

Abstract

The confused flour beetle cause economic losses in stored products, especially in products obtained from wheat. Although using insecticides against storage pests is an effective method, their frequent and continuous use can lead to resistance and toxicity issues in non-target organisms. In this study, the effect of local Beauveria bassiana isolates (BMAUM LD.2016 and BMAUM M6-4) on the 3rd instar larvae of confused flour beetle (Tribolium confusum) was determined under laboratory conditions. As a result of the experiment, both isolates of B. bassiana were found to be more effective on the larvae in the spraying method compared to the dipping method. In the spraying method, mortality rates on the 9th day were 72% in BMAUM LD.2016 isolate, 34% in the dipping method, respectively. Mortality rates of BMAUM M6-4 isolate were recorded as 96% in the spraying method and 8% in the dipping method. In the spraying method, the mortality date (LT50) was determined as 6.09 days for BMAUM LD.2016 isolate and 3.90 days for BMAUM M6-4 isolate. The LT50 value could not be calculated in the dipping method, since the mortality rates were below 50% for both isolates. BMAUM M6-4 isolate caused higher mortality in larvae than BMAUM LD.2016 isolate. As a result, B. bassiana isolates have shown a high level of effectiveness against T. confusum, demonstrating that they can be used as isolates for insect control.