What is a Plant Disease?
A plant disease is defined as any disturbance that prevents the normal growth and development of a plant and reduces its economic or aesthetic value. Diseases are caused by living agents, such as micro-organisms and parasitic plants; and by non-living agents, such as environmental factors, faulty nutrition or chemical substances. The living agents are called pathogens or biotic agents and the non-living agents are called abiotic agents.
The visible reactions of the plant to the agent are called symptoms (including wilting, stunting, yellowing, death and adnormal growth of part or all of the plant.)
An accurate diagnosis of a plant disease depends on the identification of a pathogen of the causal agent. The identification of the causal agent of a disease that has not been described previously, or one that is well known.
|
