Mapping the knowledge domain of plant growth-promoting microorganisms in solanaceous vegetable crops: a bibliometric study

Plant growth-promoting microorganisms (PGPMs) are increasingly recognized as sustainable alternatives to synthetic agrochemicals in vegetable crop production. Although research on PGPM has increased considerably, there is no bibliometric mapping exclusively for solanaceous vegetable crops. This research provides a bibliometric analysis of 5,292 peer-reviewed articles collected from the Scopus database from 2015 to 2025, using VOSviewer for network visualization and keyword co-occurrence mapping. The number of publications has steadily increased from 232 articles in 2015 to 667 in 2024, accumulating 107,067 citations and achieving a corpus-level h-index of 113. Asia (China and India) together accounted for about 37% of total output, with Asian agricultural universities being leaders in institutional productivity and European institutions showing disproportionately high citation impact. The research was published in 826 journals, Frontiers in Microbiology being the top journal. Five major knowledge clusters emerged: biocontrol and disease management; biofertilization and nutrient management; stress tolerance enhancement; molecular mechanisms and omics approaches; and application technologies. The most studied microbial genera were Bacillus , Pseudomonas and Trichoderma . Tomato ( Solanum lycopersicum ) was the most studied crop, eggplant ( S. melongena ) still largely neglected. Important research gaps are limited large scale field validation, over-reliance on single strain inoculants, lack of translation of omics findings, and absence of harmonized regulatory frameworks for commercialization. The study provides the comprehensive bibliometric mapping of PGPM research in solanaceous vegetable crops, providing a structured evidence base for researchers, funding agencies and policymakers to prioritize sustainable vegetable production.