This fungus is a type of mold that, under specific climatic conditions, can transform grapes into a prized commodity for winemaking. Botrytis cinerea pierces the grape skins, allowing water to evaporate and concentrating the sugars in the remaining juice.

Botrytis cinerea, often referred to as "gray mold," is a fungal pathogen that affects a wide range of plant species. This fungus is particularly common in environments with high humidity and moderate temperatures, making it a significant issue in many agricultural and horticultural settings. Botrytis cinerea can infect various parts of plants, including leaves, stems, flowers, and fruits, leading to rot and decay.

The fungus is known for its ability to infect both living and dead plant tissue, and it can cause significant crop losses in vegetables, ornamentals, and fruit crops, especially in grapes, strawberries, and tomatoes. In viticulture, Botrytis cinerea can cause a condition known as "noble rot" under certain conditions, which is desirable for the production of some sweet wines, like Sauternes and Tokaji, as it concentrates sugars and flavors in the grapes. However, in most cases, infection by Botrytis cinerea is detrimental and needs to be carefully managed through cultural practices and fungicide applications.