Black gram (Vigna mungo), or urad bean, suffers significant losses from soil-dwelling and foliar fungal pathogens, notably Dry Root Rot / Web Blight (Rhizoctonia bataticola / Rhizoctonia solani), Anthracnose (Colletotrichum lindemuthianum), and Powdery Mildew (Erysiphe polygoni). Rhizoctonia causes root bark rotting and sudden plant wilting under high soil temperatures and drought stress. Applying Bacillus subtilis as a seed dressing or soil drench establishes an active microbial barrier around emerging taproots and lateral roots. The bacteria colonize root tissues, producing cyclic lipopeptides (surfactin, iturin, fengycin) that disrupt fungal spore germination and inhibit hyphal expansion in soil.

Beyond disease suppression, Bacillus subtilis acts as a valuable plant growth-promoting rhizobacterium (PGPR) in pulse farming. It solubilizes fixed soil phosphorus, secretes siderophores for iron mobilization, and works synergistically with native Bradyrhizobium strains to enhance root nodulation. Stronger root expansion supports efficient water uptake, encourages uniform flowering and pod set, and increases seed weight and quality. Regular application ensures clean, residue-free black gram produce suitable for domestic and commercial pulse markets.

Importance of Bacillus subtilis in Black Gram Cultivation

Black gram is a nitrogen-fixing legume that depends on healthy roots and active Rhizobium nodules for optimum growth and grain production. Healthy root systems improve water uptake, nutrient absorption, and biological nitrogen fixation, which are essential for vigorous crop development.

Bacillus subtilis rapidly colonizes the rhizosphere and competes with disease-causing fungi and bacteria for nutrients and space. It also produces natural antimicrobial metabolites that suppress harmful pathogens while encouraging beneficial microbial populations.

Healthy roots and nodules support vigorous vegetative growth, better flowering, improved pod formation, and higher grain yield.