A disease that can damage both tobacco seedlings and mature plants. It develops in humid conditions and is recognizable by the brown spots which appear on the leaves; these spots rapidly develop a bluish-grey coating, and the leaves eventually wither.

A damaging fungus that forms on the tobacco leaf. Under the right conditions, it can ruin an entire tobacco field in a matter of days. Blue mold flourishes in cool, cloudy weather with light rain. Tobacco leaves affected by blue mold have small round blemishes.

Peronospara tabacina is a fast moving, airborne fungus that can ruin a tobacco field in just a few days. It flourishes in cool, cloudy weather with light rain and riddles tobacco leaves with small round blemishes.