Sesame (Sesamum indicum), or til, suffers heavy yield losses from soil-borne stem rots and foliar blights, notably Charcoal Rot / Stem Rot (Macrophomina phaseolina), Phytophthora Blight (Phytophthora nicotianae var. sesami), and Cercospora Leaf Spot (Cercospora sesami). Macrophomina causes root rotting and stem girdling during warm, dry conditions, leading to premature capsule shattering. Applying Bacillus subtilis as a seed dressing or foliar spray establishes a biological barrier over root zones and stem bases. The bacteria colonize host surfaces, producing cyclic lipopeptides (surfactin, iturin, fengycin) that disrupt fungal spore germination and stop hyphal expansion in plant tissue.

Beyond disease control, Bacillus subtilis acts as a valuable plant growth-promoting rhizobacterium (PGPR) in short-duration oilseed crops. It solubilizes fixed soil phosphorus, secretes siderophores for iron mobilization, and produces growth regulators that encourage rapid root expansion. Enhanced root health supports branching, improves capsule retention, and increases seed weight and oil content. Regular application ensures clean, high-grade sesame produce.

Importance of Bacillus subtilis in Sesame Cultivation

Sesame productivity depends on strong root establishment and continuous nutrient uptake throughout flowering and capsule development. Healthy roots improve water absorption, support efficient nutrient transport, and help plants withstand drought during reproductive stages.

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

Healthy roots promote vigorous branching, increase capsule numbers, improve seed development, and enhance oil accumulation.