Groundnut (peanut) cultivation suffers severe yield reductions due to seedling collar rot (Aspergillus niger), stem rot/Sclerotium wilt (Sclerotium rolfsii), and foliar diseases like Tikka leaf spot (Cercospora spp.). Treating seed kernels and applying Bacillus subtilis to the soil matrix provides biological defense against soil-dwelling and seed-borne fungal pathogens. The bacteria rapidly establish colonies in the pod zone and rhizosphere, producing antifungal lipopeptides (surfactin, iturin) that inhibit sclerotia germination and fungal hyphal establishment.

Beyond disease control, Bacillus subtilis serves as a key plant growth-promoting rhizobacterium (PGPR) for oilseed legumes. It mobilizes insoluble soil phosphorus, releases bound iron through siderophore activity, and works alongside native Rhizobium populations to support root nodulation. Enhanced root and nodule health improves plant vigor during pegging and pod development stages, resulting in uniform pod development, better shell filling, and higher seed oil content. Utilizing Bacillus subtilis ensures clean, residue-free produce, minimizing aflatoxin risks and supporting sustainable oilseed production.

Importance of Bacillus subtilis in Groundnut Cultivation

Groundnut requires a biologically active root zone throughout its growth cycle because flowering occurs above the soil surface while pod formation takes place below ground. Healthy roots are essential for nutrient uptake and successful peg penetration into the soil.

Bacillus subtilis rapidly colonizes the rhizosphere, competing with harmful microorganisms for nutrients and space. It produces protective biofilms and antimicrobial metabolites that help reduce disease pressure around roots and developing pods.

Healthy soil biology supports vigorous plant growth, improved peg formation, better pod filling, and increased kernel quality.