The increasing demand for sustainable agriculture has intensified interest in beneficial microbes as eco-friendly alternatives to chemical pesticides for plant disease control. Among these, plant growth-promoting rhizobacteria (PGPR) have attracted great interest because they can suppress plant pathogens and strengthen plant health through molecular mechanisms. Recent studies suggest that PGPR protect plants from disease not only by directly attacking pathogens but also by changing how plant immune genes are expressed through epigenetic processes. This review brings together current knowledge on epigenetic regulation in plant–PGPR interactions, focusing on DNA methylation, histone modifications, and non-coding RNA pathways. PGPR colonization activates plant immune signaling through pattern recognition receptors, MAPK cascades, reactive oxygen species, and plant hormones. The review also covers the range of bacterial signals—including lipopolysaccharides, flagellin, cyclic lipopeptides, and volatile organic compounds—that prepare plant defenses, and explains how the recognition of these signals reshapes chromatin structure at defense genes. In addition, the review discusses how these changes may influence induced systemic resistance and examines emerging, though still limited, evidence on whether they could potentially be transmitted to subsequent generations. A better understanding of how microbial signals regulate host epigenetics may reveal new ways to improve plant immunity and balance growth with defense. Overall, available evidence indicates that PGPR-induced epigenetic changes represent a promising and environmentally friendly approach to crop protection; however, field-level validation and mechanistic confirmation in non-model crop species remain necessary before this strategy can be considered practically applicable.

Phosphorus (P) is a vital macronutrient required for plant growth and development; however, only a small fraction is readily available for plant uptake because much of the soil phosphorus becomes immobilized through chemical fixation. Moreover, dependence on finite phosphate rock reserves and the intensive use of mineral phosphorus fertilizers increase production costs and raise environmental concerns, emphasizing the need for more sustainable phosphorus management strategies. Phosphate-solubilizing bacteria (PSB) are key drivers of microbial phosphorus cycling, enhancing phosphorus bioavailability by transforming insoluble inorganic and organic phosphorus compounds into forms that plants can readily absorb. This process is mediated by the secretion of organic acids, phosphatases, phytases, and other metabolites involved in phosphorus mobilization. In addition to increasing phosphorus bioavailability, PSB can enhance overall nutrient-use efficiency, promote root growth and architecture, support biological nitrogen fixation, and strengthen plant resilience to abiotic stresses, including drought, salinity, and temperature extremes. Owing to these multiple plant growth-promoting functions, PSB are increasingly recognized as promising bioinoculants that can improve crop productivity, enhance climate resilience, and reduce reliance on synthetic phosphorus fertilizers. This narrative review provides a comprehensive overview of recent advances in understanding PSB-mediated microbial phosphorus cycling, with particular emphasis on the mechanisms underlying phosphorus solubilization, interactions with plant roots, and contributions to sustainable crop production. Evidence from laboratory, greenhouse, and field studies is synthesized to evaluate PSB-mediated mechanisms, plant responses, and their potential for agricultural application. The review also highlights key barriers to the widespread adoption of PSB, including inconsistent field performance and challenges associated with commercialization. Addressing these limitations could support the development of cost-effective biofertilizers that increase phosphorus-use efficiency, reduce dependence on mineral fertilizers, lower production costs, and enhance farm profitability while contributing to sustainable agriculture.

Tomato (Solanum lycopersicum L.) is one of the most widely cultivated vegetable crops, and its productivity is significantly affected by soil-borne diseases. In this study, fungi were isolated from infected tomato roots and their pathogenicity was evaluated. Root samples were processed using standard microbiological techniques and cultured on potato dextrose agar (PDA). A total of eight fungal isolates were obtained. Pathogenicity tests were conducted on healthy tomato seedlings under controlled conditions. The results showed that only one isolate exhibited strong pathogenicity, causing typical disease symptoms. These findings indicate the coexistence of pathogenic and non-pathogenic microorganisms in the tomato rhizosphere and emphasize the importance of pathogenicity assays in identifying disease-causing agents.

In this study, endophytic bacteria were isolated from tomato root tissues and their antagonistic activity against pathogenic fungi (Fusarium solani and Fusarium oxysporum) was assessed. The isolated bacterial strains were purified and characterized using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF MS). Antagonistic activity against Fusarium solani and Fusarium oxysporum was assessed in vitro using a dual culture method. Several isolates showed significant inhibitory effects on the growth of both fungal pathogens, indicating their potential as biological control agents. These endophytic bacteria may serve as promising candidates for the development of biofungicides for sustainable tomato production.

This research article examined the in vitro phosphate-solubilizing properties of endophytic bacteria isolated from various plants and their impact on plant growth and development under hydroponic conditions.