Herbicid eliminate plants threat grow where they are n ot wanted. The four main types of pesticides are(i) Herbicides (ii) Fungicides (iii) Rodenticieds (iv) Insecticides. The agricultural use of DDT is now leaned under the stock holm convention, but it is still used in some developing nations.Ĭlassification Pesticodes are classified according to the pests they control. In 1960s it was discovered that DDT was preventing many fish eating birds from reproducing, which was a serious threat to biodiversity. Some sources consider the 1940s and 1950s to have been the start of the “Pesticideera” Pesticide use has increased 50 field since 1950 and 2.3 million tonnes of persticides are now used each year. In 1940s manufactures began to produce large amounts of synthetic persicides and their use become wide spread. The 19th century saw the introduction of two more natural persticides, pyrethrum, which is derived from chrysanthemums, rotemone which is derived from the roots of tropical vegtables. By the 15th century, toxic chemicals such as arsenic, mercury and led being applied sulphate was extracted from tobacco leaves for use an an insecticide. The first known persicide was elemental sulphur dusting used in ancient summer about 4500 years ago in ancient Mesopotamia. History Since before 20BC, humans have utilized pesticides to protect their crops. The term includes substances intended for use as a plant growth regulator, defoliant, desiccant or agent for thining fruit or preventing the premature fall of fruit and substances applied to crops either before or after harvest to protect the commodity from deterioration during storage and transport. Althoufh there are also drawbacks, such as potential to humans and other animals. Pests includes insects, plant pathogens insects, mollusces, birds, mammals, fish nematodes and microbus that destroy property, spread disease or are a vector for disease or cause a nuisance. A pesticide may be a chemical substance, biological agent antimiolbal disinfectant or device used against any pest. A pesticide is any substance is mixture of substance intended for preventing, destroying repelling or mitigating any pest. This great feat has been achieved by adopting new methods of forming and by expensive use of fertilizers and insecticides. Aim To Study the presence of insecticides or pesticides (Nitrogen Containing) in various fruits and vegetables Theory In the decade, there has been a tremendous increase in the guilds of various crops to meet the demand of our growing wrold population.
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