Toxicity of Insecticides to Pollinators in Cucumber Vis-À-Vis Tolerant Gut Microbiota of Apis dorsata Fabricius NP Trivedi, DB Sisodiya, BL Raghunandan 1 , NB Patel 1 , RK Thumar 2 , RG Parmar 3 Department of Entomology, 2 Department of Nematology 3 Department of Plant Pathology BA College of Agriculture, Anand Agricultural University, Anand, Gujarat – 388110, India 1 AICRP on Biological Control of Crop Pests, Anand Agricultural University, Anand, Gujarat – 388110 The toxicity of insecticides to pollinators visiting cucumber flowers was studied wherein spinosad, fipronil and flonicamid exhibited the higher activity of pollinators validating their relatively safer nature towards pollinators while, the lower activity was observed in plots treated with imidacloprid, spiromesifen, chlorantraniliprole as well as cypermethrin which confirmed their more toxicity to pollinators. Total fifteen bacterial isolates were identified from the hind gut of giant honey bee, Apis dorsata L. which consisted five genera viz., Bacillus sp., Klebsiella sp., Citrobacter sp., Providencia sp. and Enterobacter sp. Some of the bacterial isolates exhibited significant growth in the presence of insecticides. Keywords: Honey bees, Apis dorsata Fabricius, Pollinators, Insecticide tolerant bacteria Climate change, pollution and indiscriminate use of chemicals are affecting population of pollinators making them even extinct one day, if not taken seriously. Detrimental effects of indiscriminate use of insecticides occur not only to humans but to pollinators which would result in reduction of pollinators’ biodiversity. At the same time, high production of food commodities is not possible without use of insecticides. Hence, there is an urgent need to find a way to use insecticides as well as conservation of pollinators for high as well as sustainable agricultural production. Use of pesticides in cross pollinated crops like cucumber in which pollinators (mainly honey bees) are the only source of pollination, has negative impacts on pollinators (Khalifa et al, 2021). Hence, it is very important to know which groups of insecticides have adverse effects on pollinators that can be used in cucumber. But use of insecticides cannot be completely eliminated due to some major insect- pests ie, cucumber beetle and fruit fly ( 2023). Hence, there is a need to find a way to use insecticide along with its safety to pollinators. As a solution, pesticide degrading gut bacteria could be the answer. There are several reviews showing some bacteria degrading different pesticides in nature (Pathak et al, 2022; Kumar et al, 2021). Many researchers utilised soil having long history of pesticide contamination to isolate such bacteria having pesticide degrading characteristics. Correspondence: nikhiltrivedi00@gmail.com Some soil inhabiting bacterial strains with pesticide degrading characteristics have been identified Klebsiella pneumoniae (Phugare et al, 2013); Citrobacter sp. (Chaussonnerie et al, 2016); Bacillus sp (Pankaj Sharma et al, 2016); Bacillus cereus (Gangola et al, 2021) and Rhizobium sp, Bacillus subtilis, Pseudomonas putida F1, Brevibacterium sp. and Bacillus sp. (Sabourmoghaddam et al, 2015). There are references showing bacteria other than the present study, which also degrade pesticides, are Pseudomonas spp. (Pandey et al, 2009); Acinetobacter sp, Artrobacter sp and Pseudomonas putida (Monica et al, 2016) and Achromobacter sp and P seudomonas sp. (Briceno et al, 2020). Use of insecticide degrading bacteria can revolutionise whole scenario of agriculture. The present investigation was therefore carried out to identify and reveal the role of gut bacteria of honeybee, Api sdorsata Fabricius in degradation of pesticides. MATERIALS AND METHODS A field experiment was conducted by growing cucumber (var. Gujarat Cucumber 1) following all standard agronomical practices (Spacing: 1.5 x 1.0 m; Gross plot size: 6.0 x 6.0 m; Net plot size: 3.0 x 4.0 m) following randomized block design with ten treatments and three replications at Entomology Farm, BA College of Agriculture, Anand Agricultural University, Anand (Gujarat) during summer, 2020 and 2021. Pesticide Research Journal Vol. 36 (1) 68-73, June 2024 doi:10.5958/2249-524X.2024.00012.X