The First Field Evaluation of Bacillus thuriengiensis Bt407 against Cassida vittata and Its Natural Enemies In Egyptian Sugar Beet Fields.

The scientific community working in the field of insect pathology is experiencing an increasing academic and industrial interest in the discovery and development of new bioinsecticides as environmentally friendly pest control tools to be integrated with chemicals in pest management programs. Therefore, field studies were conducted at the experimental farm of Sakha Agricultural Research Station during the 2019/2020 and 2020/2021 seasons for estimating the efficiency of the new strain, Bacillus thuriengiensis Bt407 (identified in Germany, GATC company) against Cassida vittata Vill larvae and their predators. Moreover, calculating the percentages of parasitism on C. vittata eggs and on C. vittata larvae-pupal compared to some conventional insecticides; Penadryl 10% EC. (Pyridalyl) and Coragen 20% SC. (Chlorantraniliprole). The overall average of reductions in this insect were 69.45 and 75.21% by Bacillus, 78.96 and 81.52% by Penadryl, and 79.06 and 81.31% by Coragen during the two seasons, respectively. On the other hand, the overall average reductions in P. alfierii were 48.88 and 47.51% by Bacillus, 94.18 and 88.65% by Penadryl, and 90.60 and 84.52% by Coragen. Coccinella undecimpunctata decreased by 38.13 and 34.99% by Bacillus, 90.27 and 88.16% by Penadryl, and 92.63 and 79.47% by Coragen. Chrysoperla carnea dropped by 38.45 and 49.7% by Bacillus, 92.24 and 91.50% by Penadryl, and 90.39 and 84.17% by Coragen during the two seasons, respectively. Further, the mean number of emerged parasitoids and parasitism percentages were higher in Bacillus-treated plots than in conventional insecticide-treated plots through the two seasons. Lastly, these findings demonstrate that this bacterium strain is effective in reducing C. vittata larvae populations, but not of their predators and parasitoids compared to conventional insecticides. Thus, it could be recommended to enroll this strain in the IPM of sugar beet insects.