Plant growth-promoting bacteria used in maize cultivation: a systematic literature review (2015–2025)
Maize (Zea mays L.) is one of the most economically important cereals worldwide, contributing significantly to the economies of many countries. Its production model relies heavily on synthetic fertilizers, which contribute to environmental degradation. Plant growth-promoting bacteria (PGPB) are among the sustainable alternatives used to partially replace these inputs, as they can enhance maize growth by optimizing nutrient uptake, increasing disease resistance, and promoting soil health. This study aimed to synthesize information from the last ten years (2015–2025) regarding PGPB applied to maize cultivation. Searches were conducted across five databases—PubMed, ScienceDirect, Scopus, Web of Science, and LILACS—identifying 1,333 articles. After the screening process, 65 articles were included in the review. The included studies were predominantly conducted in two countries: Brazil and China. The most frequently reported bacterial species were Bacillus subtilis (27%), Azospirillum brasilense (23%), and Pseudomonas fluorescens (12%). Among the functional traits, phytohormone production was the most frequent (75%), followed by biological nitrogen fixation (49%), phosphate solubilization (48%), and siderophore production (32%). Biofilm production (8%) was the least frequent trait. Classifying the articles by biostimulation category revealed that the assessment of growth and yield parameters (95%) predominated, whereas abiotic stress tolerance (22%) and biocontrol and crop protection (18%) were less frequent. This review demonstrates that several genera of plant growth-promoting bacteria have been proportionally under-studied in the field over the last decade, highlighting potential knowledge gaps regarding their effects on physiological and yield parameters in maize crops, particularly in the face of stress and global climate challenges.