Unlocking the strength of plant growth promoting Pseudomonas in improving crop productivity in normal and challenging environments: a review

The widespread use of biofertilizers, rather than chemical fertilizers, is significantly more likely to accomplish sustainable agriculture production globally. Plant growth-promoting rhizobacteria (PGPR) are chemical-free alternatives to conventional crop protection in agriculture. Pseudomonas spp. are unique among the PGPR genera in terms of root colonization, nitrogen fixation, production of exopolysaccharides, siderophores, hydrogen cyanide (HCN), and phytohormones, solubilization of phosphorus, potassium, and zinc, biofilm formation, antioxidant activities, stress adaptation abilities, and positive interactions with other microbial communities. They also aid plant development by promoting biotic and abiotic stress tolerance, as well as supporting host plant nutrition. Pseudomonas is regarded as an environmentally acceptable alternative to harmful chemical fertilizers because of its active growth-promoting actions. However, to achieve this goal, workers must first get a complete understanding of the numerous processes used by Pseudomonas, allowing them to fully exploit the bacteria potential in the future. Therefore, the present review has been undertaken to discuss the fundamental processes used by Pseudomonas spp. to promote plant development and reduce environmental stresses. In addition, we described some reported Pseudomonas-based biofertilizers worldwide and the presence of potential genes in the genome of different Pseudomonas strains to understand the mechanism of Pseudomonas mediated plant growth promotion at the molecular level.