Suppressing Tea Blister Blight, Black Rot, and Root Rot with Bacillus subtilis

Tea estates in humid, high-altitude regions suffer recurring yield losses from destructive foliar and root pathogens, most notably Blister Blight (Exobasidium vexans), Black Rot (Corticium invisum / Corticium theae), and Charcoal Stump Rot (Ustulina zonata). Mist, high rainfall, and dense bush canopies create ideal conditions for fungal spore spread across tender plucking shoots. Applying Bacillus subtilis as a foliar spray following plucking rounds establishes a protective biological barrier on young leaves and stems. The bacteria rapidly colonize cut shoot surfaces and leaf tissues, releasing antifungal lipopeptides (iturins, fengycins) that disrupt fungal spore germination and hyphal development.

Beyond disease suppression, Bacillus subtilis serves as a key plant growth-promoting rhizobacterium (PGPR) in tea plantation soils. Applied via soil drenching or drip fertigation around the bush root zone, it solubilizes bound soil phosphorus, mobilizes iron via siderophore production, and supports active feeder root development. Enhanced root health drives shoot growth, leading to faster plucking flush recovery, higher shoot density, and increased green leaf yield without leaving harmful chemical residues in finished tea leaves.

Major Benefits

• Promotes extensive root development
• Suppresses root rot, collar rot, Fusarium, Rhizoctonia, and nursery diseases
• Improves nutrient absorption
• Enhances new leaf flush
• Improves leaf size and quality
• Supports stress tolerance
• Improves long-term soil fertility

Recommended Application

• Nursery treatment
• Soil application
• Basin application
• Drip irrigation