Pheno-morphological and biochemical characterization of root nodules and associated root nodulating bacteria from Pongamia pinnata (L.) Pierre in the arid regions of India

The study demonstrates that both soil nutrient status and nodule biochemical composition jointly regulate <i>P. pinnata</i> growth under arid conditions. High-performing isolates, particularly PP-18, PP-19, and PP-20, possess favourable physiological and biochemical attributes supportive of plant growth. The strong discriminatory power of PCA and clustering highlights the ecological differentiation among isolates across fertility gradients. These results underscore the potential of selecting site-specific, elite RNB strains to enhance <i>P. pinnata</i> productivity, soil fertility, and sustainable agroforestry in arid landscapes.