In a wide sense, may be defined as any organism which harms or causes damage to man directly or indirectly, is called a pest. In agriculture, pests are the organisms which may cause quantities or qualitative losses to our crops. E.g insects, mites, weeds, fungus, algae, snails, slugs, different pathogens, rodents etc.A pest is any animal or plant detrimental to humans or human concerns, including crops, livestock and forestry, among others. The term is also used of organisms that cause a nuisance, such as in the home. An older usage is of a deadly epidemic disease, specifically plague. In its broadest sense, a pest is a competitor of humanity. A pest is any living organism, whether animal, plant or fungus, which is invasive or troublesome to plants or animals, human or human concerns, livestock, or human structures. It is a loose concept, as an organism can be a pest in one setting but beneficial, domesticated or acceptable in another.
Plant pests can be classed as monophagous, oligophagous, andpolyphagous according to
how many hosts they have. Alternatively, they can be divided by feeding type,
whether biting and chewing; piercing and sucking; or Lapping and chewing.
- Lecturer : Nnamdi Chukwu Amadi