PLPA 200 Lecture Notes - Lecture 1: Necrosis, Phytophthora Infestans, Microorganism

• School: University of Illinois
• Department: Plant Pathology
• Course: PLPA 200
• Professor: Eastburn Darin

Document Summary

The plant disease triangle is a diagrammatic representation of the three fundamental elements required for disease: a susceptible plant, a pathogen capable of causing disease, and a favorable environment. If any of these three elements is missing, no disease occurs. Many factors influence a plant"s susceptibility to disease, including its growth stage, its genetic makeup, and stress. These same factors also influence diseases in animals, including people. Symptoms are the expression of disease by a plant in response to the activities of the pathogen. Symptoms may be localized, such as spots on leaves, or systemic, such as blighting of the entire plant. Symptoms can involve necrosis, or death, of part or all of the plant, or can involve changes in the color or the shape of the plant. Many plant diseases are caused by living, or biotic, parasites. A parasite is an organism that obtains its nutrients from other living organisms.