LABORATORY AND FIELD EVALUATION OF A CYPERMETHRIN-BASED INSECTICIDE FOR THE CONTROL OF ALPHITOBIUS DIAPERINUS PANZER (COLEOPTERA: TENEBRIONIDAE) AND ITS IN-VITRO EFFECTS ON BEAUVERIA BASSIANA BALS. VUILL. (HYPOCREALES: CORDYCIPITACEAE)

ABSTRACT The control of Alphitobius diaperinus is based mainly on chemical insecticides, and the indiscriminate and incorrect use of these products has led to failures in insect control. Thus, it is important to monitor the efficiency of the products available on the market and to develop alternative insect control strategies. The present study evaluated the effect of a new product (cypermethrin-6%) under laboratory and field conditions and assessed its in-vitro compatibility with the fungus Beauveria bassiana (Unioeste 4 isolate). Its efficiency in dry powder and wettable powder formulations was also assessed in the laboratory through comparison with a similar insecticide (cypermethrin-5%) at five different concentrations. The field assays were conducted in two commercial broiler breeder houses (Treated and Control), applying the new product on the litter at the manufacturer's recommended concentration (RC). Germination, vegetative growth, conidial production, number of colony forming units (CFUs) and insecticidal activity of the fungus were used to evaluate the compatibility of the insecticide. The effects of the cypermethrin-6% product and cypermethrin-5% were equivalent in the laboratory, and the new product exhibited better performance at lower concentrations (1/4RC, ⅛RC). The strategy applied in the field reduced the insect population in up to 96% after 75 days. Additionally, all concentrations of cypermethrin-6% were compatible with the fungus under the evaluated in-vitro conditions. Therefore, the new product is considered selective for B. bassiana. Further studies are necessary to assess its compatibility under field conditions, consolidating this strategy as a viable alternative for managing this pest.