A localized area of discolored, diseased tissue. Grey or white powdery growth on the plant surface. Leaves are the most common place to see mildew. Also characterized by intermingled patches of normal and light green or yellowish color. A common symptom of many viruses.
Necrosis is dead tissue or plant parts.
A chemical compound or physical agent that kills or inhibits nematodes. Microscopic, wormlike animals that live saprophytically in water or soil, or as parasites of plants and animals. An entity that can incite disease. The capability of a pathogen to cause disease. Small, blister-like elevation of epidermis created as spores form underneath and push outward.