The hidden allies in weeds: Plant growth-promoting and thermotolerant bacteria for heat-resilient rice production

Abstract

Weeds, though often viewed as crop competitors, host diverse bacterial communities with remarkable plant growth-promoting and stress-mitigating potential. These weed-associated bacteria exhibit key functional traits such as nitrogen fixation, phosphate solubilization, phytohormone synthesis, and ACC deaminase activity, which collectively enhance rice growth and nutrient uptake. Many isolates also impart thermotolerance by boosting antioxidant defence, osmolyte accumulation, and membrane stability under heat stress. Harnessing these beneficial microbes offers a sustainable strategy to improve rice resilience while reducing dependence on chemical inputs. This review highlights the diversity, mechanisms, and applications of weed-associated bacteria in promoting growth and heat stress tolerance in rice under changing climatic conditions.