Plant growth promoting rhizobacteria (PGPR) and their role in plant-parasitic nematodes control: a fresh look at an old issue

The increasing demand for agricultural products can be met by maximizing production potential and reducing crop losses caused by common plant-parasitic nematodes. Chemical-based nematode management is a successful technique for mitigating damage and yield losses caused by nematode pests; however, inappropriate and irresponsible application of synthetic pesticides has negative impacts on fauna, bioflora, and natural enemies such as predators and parasites. The use of biocontrol agents is the most appreciated method for nematode control among farmers because it's safe and reduces environmental pollution. There is increasing focus on the biological control of plant-parasitic nematodes using plant growth-promoting rhizobacteria (PGPR) as a biopesticide. Moreover, PGPR strains can promote plant growth by producing various secondary metabolites of these PGPRs. This review focuses on the direct (Nitrogen fixation, phytohormone formation, phosphate solubilization, Potassium solubilization, siderophores and ammonia production) and indirect mechanisms (Hyperparasitism, antibiosis, lytic enzyme production, induced systemic resistance) of action of PGPR in plant-parasitic nematodes management, and the future prospects of PGPR-based plant-parasitic nematodes biocontrol agents.