Isolation and characterization of plant growth promoting rhizobacteria from cacti root under drought condition

Curr Res Microb Sci. 2024 Nov 15:8:100319. doi: 10.1016/j.crmicr.2024.100319. eCollection 2025.

Abstract

Plant growth-promoting rhizobia (PGPR) helps plants grow and develop by protecting them from abiotic and biotic stresses, increasing the synthesis of chemicals that promote growth, and enabling the uptake of nutrients. Drought is one of the biggest problems throughout the world. The search for novel and efficient drought-resistant microorganisms that reduce the adverse effects executed by drought is a significant alternative. This study aimed to isolate and characterize PGPR strains from the Opuntia Ficus-Indica cactus plant's rhizosphere, cultivated in the semi-arid Shankargarh district of Uttar Pradesh, India. Tests for plant growth-promoting activity, such as the generation of indole acetic acid (IAA), phosphate solubilization, ammonia, carboxymethyl cellulase, and protease activity, were performed on all bacterial isolates. There were 246 bacterial strains isolated from the rhizospheric zone, and only 16.6 % showed drought resistance and various plant growth-promoting traits. The Bacillus sp. strain promoted the growth promotion of Capsicum annum L. under water stress (30 % field capacity). Additionally, Bacillus sp. isolates, with their potential for drought tolerance and plant growth promotion, could be applied in sustainable agriculture to enhance crop yield and resilience to water scarcity.

Keywords: 16S rRNA gene; Cacti; Drought; Plant growth-promoting bacteria; Plant-associated bacteria; Water stress.