Effect of Geraphene oxide nanosheets on efficiency of Bacillus thuringiensis biological pesticide

Biological insecticide Bacillus thuringiensis (Bt) is known as the most important and most commonly biological control agents in the world. One of the most important factors that disable Bt in nature is ultraviolet radiation. Maintaining bacterial resistance against environmental conditions causes widespread increases of this bacterium as a pest control agent. The objective of the present study was to evaluate the protective effectiveness of graphene oxide (GO) on spore viability of Bt subsp. KD-2 against Ultra Violet-A (UV-A) radiation. In this regards, bioassay of nano and non-nano formulations were carried out against second-instar larvae of Ephestia kuehniella. After 120 h exposure to UV-A, spore viability of the nano-formulation and free spore formulation were 28.43± 0.36 % and 19.29 ± 0.69 %, respectively. The mortality of irradiated free spore formulations and non-nano formulation on the second-instar larvae of E.kuehniella were 22 ±3.05% and 35±2.88% on the 10th day of the experiment. Therefore, the results of this study showed that nanosheet of GO can be used as protective UV-A for Bt formulation.