Plant Growth-Promoting Rhizobacteria Involved in Enhancing Drought Tolerance in Crops: A Bibliometric Review

Drought is considered one of the most devastating abiotic stresses that limit crop production worldwide. This emphasizes the urgent need for innovative strategies to enhance crop drought tolerance. Plant growth-promoting rhizobacteria (PGPR) capable of promoting plant growth by direct or indirect mechanisms have been seen as potential agents for enhancing crop drought tolerance in past decades. In this study, we performed an extensive bibliometric analysis using the Web of Science Core Collection to illuminate the scientific landscape surrounding PGPR-mediated drought tolerance. We assessed data from 1,680 peer-reviewed research articles that were published in the period 1986-2025. The gradual increase in publications and citations in the past decade underscores the growing interest in PGPR applications in drought stress management. The increasing keyword co-occurrence of “growth-promoting rhizobacteria” with “drought”, “drought stress”, and “tolerance”, reflects the growing research interest in microbial strategies to enhance drought tolerance. In addition, the rise in studies from Asia and the Middle East, regions significantly impacted by climate change, reflect growing global interest in this field. Our analysis identified six major research clusters, highlighting key trends and growing scientific attention toward PGPR-mediated drought tolerance. While broad themes remain prominent, there is increasing focus on specialized topics such as “rhizosphere microbiome”, “ACC deaminase”, and “systemic resistance”, which are associated with higher citation impact. This shift reflects a growing interest in uncovering the molecular and microbial mechanisms that enhance crop tolerance under drought stress. These insights offer valuable direction for future strategies to improve drought tolerance in crops.Keywords: Plant-microbe interactions; Climate change; Drought stress; Stress tolerance; Sustainable agriculture