Pests vegetables

Plants can also be pests that need to be controlled, particulady noxious weeds infesting food crops. Prior to 1900, inorganic compounds such as sulfuric acid, copper nitrate, sodium nitrate, ammonium sulfate, and potassium salts were used to selectively control mustards and other broadleaved weeds in cereal grains. By the early 1900s, Kainite and calcium cyanamid were also used in monocotyledenous crops, as well as iron sulfate, copper sulfate, and sodium arsenate. Prom 1915 to 1925, acid arsenical sprays, carbon bisulfate, sodium chlorate, and others were introduced for weed control use. Total or nonselective herbicides kill all vegetation, whereas selective compounds control weeds without adversely affecting the growth of the crop (see Herbicides). 

The discovery that, in industrialised societies, diets deficient in fruits and vegetables can effectively double the risk of developing many different types of cancer has focused renewed attention on the beneficial properties of these foods (Block e/a/., 1992 Patterson ef a/., 1990 Southon and Faulks, 2002). As we have seen, plant foods are rich in micronutrients, but they also contain an immense variety of biologically active secondary metabolites providing colour, flavour and natural toxicity to pests and sometimes humans (Johnson et ah, 1994). The chemistry and classification of such substances is still a matter for much research and debate, but this has not prevented attempts to isolate and exploit substances that have variously been termed protective factors , phytoprotectants , phytochemicals and nutraceuticals . Phytochemical compounds include ... 

Acetamiprid is a neonicotinoid insecticide with outstanding systemic activities and a broad insecticidal spectrum. Acetamiprid controls diverse soil and foliar insect pests infesting cotton, sugar beet, vegetables, fruits and other major food crops by both contact and stomach action... 

Each insecticide, fungicide, rodenticide, herbicide, or other pest control product must be registered with the State Bureau of Chemistry as an economic poison before being offered for sale in California. Registration may be refused, after hearing, for a product that is of little or no value for the purpose intended, or that is detrimental to vegetation (except weeds), to domestic animals, or to the public health and safety, when properly used. 

Langer, V. (1995). Pests and diseases in organically grown vegetables in Denmark A survey of problems and use of control methods , Biological Agriculture and Horticulture, 12 (2) 151-171. 

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