Phylogeny of indigenous <i>Beauveria bassiana</i> isolates from <i>Leptinotarsa decemlineata</i> in Türkiye and their biocontrol potential

The Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), is a serious pest of potatoes and other solanaceous plants such as eggplant, tobacco and tomato. Chemical insecticides are the main management tool for CPB, but it has been reported that resistance to the insecticides can develop rapidly. Therefore, it is important to seek indigenous biocontrol agents and develop environmentally friendly control methods against this pest. In this study, 13 entomopathogenic fungi (11 from adults and 2 from larvae) were isolated from the field collected CPB in K & imath;r & scedil;ehir, T & uuml;rkiye and they were identified as Beauveria bassiana based on bloc gene sequence data. These B. bassiana isolates were also tested against CPB larvae and adults under laboratory conditions. The highest mortality and mycoses values against both larvae and adults were obtained from B. bassiana LD-3 and LD-9 with 90, 93.33% and 56.66, 86.66% for larvae and 96.66, 93.33% and 93.33, 90% for adults, respectively. Some of these B. bassiana isolates are promising candidates for inundative biological control of CPB in T & uuml;rkiye, but field testing is required to further elucidate their biocontrol potential.