PERTANIKA JOURNAL OF TROPICAL AGRICULTURAL SCIENCE

Sustainable agricultural productivity increasingly relies on plant growth-promoting microorganisms (PGPMs), which include plant growth-promoting rhizobacteria (PGPR) and fungi (PGPF). These beneficial microbes enhance crop growth by improving nutrient acquisition through processes such as nitrogen fixation, phosphate solubilization, and the synthesis of phytohormones. As a result, they help reduce the need for chemical fertilizers and pesticides. Additionally, PGPMs mitigate plant pathogens by producing antimicrobial compounds, inducing systemic resistance, and competing for ecological niches, resulting in significant reductions in disease incidence and severity. However, despite their demonstrated effectiveness in controlled environments, the performance of PGPMs in real-world agricultural systems is often inconsistent, with efficacy declining by 30-50% due to factors such as abiotic stressors, ecological incompatibilities, and reduced microbial viability. To overcome these challenges, this review presents a strategic framework focused on strain-specific adaptation to local soil and climate conditions, optimized co-inoculation strategies, and omics-guided selection of resilient microbial consortia. These approaches aim to bridge the gap between laboratory success and field performance, enhancing the stability and reliability of PGPM-based solutions. By identifying and addressing critical barriers to PGPM adoption, this review seeks to advance microbial technologies that promote sustainable farming, improve crop quality, and ensure global food security despite climate variability.