Bacterial volatiles as PGPRs: Inducing plant defense mechanisms during stress periods.

• Soil microbes can produce organic volatiles in both aerobic and anaerobic environments. • Bacterial volatile compounds of various chemical types are often formed by catabolic processes. • Enhancing plant development, abiotic stress tolerance and disease resistance may also be caused by microbial VOCs. • The influence of microbial volatiles on plant growth induction is an attractive field of study that has so far been explored. The increase in population and food demand has led to the excessive utilization of chemical fertilizers. These fertilizers, in turn, affected the soil properties and decreased the fertility of the soil. The side effects of these chemicals have forced scientists to focus on plant growth-promoting rhizobacteria (PGPR) for sustainable farming. Some microbes and plants have a mutual relationship, and they use to help each other in various ways Rhizobacteria that promote plant growth enhance health of the plant and growth by increasing nutrient accessibility and assisting plants during abiotic and biotic stress. By direct or indirect mechanisms, the bacterial releases of volatile organic compounds (VOCs) are crucial in boosting plant development and disease resistance. The release of a range of low-molecular weight hydrocarbons, including the growth-promoting volatile organic compounds, 3‑hydroxy-2-butanone (acetone), 2,3-butanediol, 2-pentylfuran, or dimethylhexadecylamine, was found by chemical analysis of bacterial volatile emissions. The plants provide nutrients and shelter to the microbes. Therefore, PGPRs play a vital role in sustainable agriculture In this review, the mechanism of action of VOCs for growth promotion and how they trigger the plant defense mechanism during biotic and abiotic stress will be addressed.This review will addressthe mechanism of action of VOCs for growth promotion and how they trigger the plant defense mechanism during biotic and abiotic stress. [ABSTRACT FROM AUTHOR]