Botrytis

Botrytis is a genus of fungi in the family Sclerotiniaceae. The best known species is Botrytis cinerea, a widespread plant pathogen that causes gray mold on many crops. The fungus also has a sexual stage, Botryotinia fuckeliana, which can complicate identification and taxonomy.

Botrytis cinerea is a necrotrophic pathogen that infects fruit, flowers, leaves, and stems of hundreds of plant species. Symptoms include brown lesions that develop a characteristic gray to brown fuzzy mold of conidia, tissue collapse, and fruit rot. The disease is commonly referred to as gray mold and is particularly problematic in moist, cool conditions.

Life cycle and ecology: Botrytis overwinters in plant debris or as sclerotia. In favorable weather, conidia are produced in large numbers and dispersed by wind. Infection requires free moisture and moderate temperatures, typically around 15–25°C. In grapes, Botrytis can cause either gray rot or, under specific conditions, noble rot, which concentrates sugars in the berries and is used to produce certain dessert wines.

Impact and management: Botrytis causes significant losses in field crops, orchard crops, and stored fruit, and is a major concern in greenhouse production. Management relies on sanitation and pruning to improve air circulation, irrigation practices to reduce leaf wetness, removal of infected material, and a judicious fungicide program with attention to resistance management. Integrated pest management strategies are commonly employed to minimize economic impact.