SOIL–PLANT–MICROBE INTERACTIONS IN LEGUME CROPS (CHICKPEA AND LENTIL): A REVIEW OF RHIZOSPHERE DYNAMICS AND NUTRIENT USE EFFICIENCY

Abstract

Legume crops such as chickpea (Cicer arietinum L.) and lentil (Lens culinaris Medik.) play a pivotal role in global food and nutritional security, providing high-quality plant protein, essential micronutrients (Fe, Zn, folate), and performing biological nitrogen fixation (BNF) that reduces synthetic fertilizer dependency and enhances soil health. This review synthesizes the complex soil–plant–microbe interactions in the rhizosphere of these pulses, emphasizing the tripartite symbiosis among legumes, rhizobia (Mesorhizobium spp. for chickpea; Rhizobium leguminosarum bv. viciae for lentil), and plant growth-promoting rhizobacteria (PGPR) such as Pseudomonas, Bacillus, and Azospirillum. Key mechanisms include enhanced nutrient acquisition (N, P, Fe via siderophores and organic acids), induced systemic resistance against biotic stresses (Fusarium wilt, Ascochyta blight), and improved abiotic stress tolerance (drought, salinity) through ACC deaminase activity, antioxidant enzyme induction, and osmolyte accumulation. The review highlights how root exudates shape microbial community assembly, the vertical transmission of core microbiota from seed to seed, and the contribution of these interactions to nutrient use efficiency (NUE), water use efficiency (WUE), and yield stability in low-input systems. Integrated strategies combining elite rhizobial inoculants, PGPR consortia, and legume-cereal rotations offer sustainable pathways to boost productivity by 20–50%, mitigate climate vulnerabilities, and combat hidden hunger in semi-arid regions of South Asia, Africa, and the Middle East.