Symptoms
Water-soaked dark-green to brown patches on leaves and stems, often with a white mouldy growth on leaf undersides in humid weather. Fruit develops firm, greasy brown rot; plants can collapse within days.
Prevention
Use certified disease-free seedlings and resistant varieties. Avoid overhead watering, stake plants for airflow, and never compost infected material.
Treatment
Organic
Apply copper-based fungicide preventively before wet spells. Remove and destroy infected foliage immediately to slow spread.
Chemical (last resort)
Apply mancozeb protectively, switching to systemic metalaxyl or cymoxanil once disease appears. Spray on a 7-day cycle during wet weather and observe PHI.
Affects 1 crop
Sources
MARDI Vegetable Disease Guide; DOA IPM Manual