Phyto and genotoxic effects of Indoxacarb and alleviation by Pseudomonas fluorescens (VITMAMJ1)

Indoxacarb (IDX), a widely used oxadiazine insecticide, can induce oxidative stress in plants. However, its combined phytotoxic and genotoxic effects and potential role of microbial mitigation remain insufficiently understood. In the current study, phytotoxicity and genotoxicity of IDX were evaluated along with protective potential of an IDX-tolerant bacterial isolate, VITMAMJ1 identified as Pseudomonas fluorescens. Seedlings of Vigna radiata, Vigna mungo, and Cajanus cajan were exposed to IDX at concentrations of 50, 100, and 150 ppm. IDX exposure significantly reduced germination and seedling vigour, with a decrease in germination index values to 8–15% at 150 ppm as compared to 100% in control treatments. The stress response was accompanied by elevated levels of oxidative stress markers and enhanced activities of antioxidant enzymes, indicating increased ROS generation. However, treatments involving VITMAMJ1 significantly lowered phytotoxic effects, improving germination indices to 54–59% at 150 ppm. Genotoxicity assessment using Allium cepa revealed a decline in mitotic index from 17.9% in controls to 2.1% at 150 ppm, while chromosomal aberrations increased from 0.56% to 89.4%. Bacterial treatments substantially restored mitotic activity (12–14%) and reduced chromosomal damage (5–7%). These findings revealed that IDX induced oxidative and cytogenetic stress in plants, while VITMAMJ1 effectively mitigated these effects.