Alternatives Pesticide

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the term push-pull established in 1987 approach integrated pest management (ipm). strategy uses mixture of behavior-modifying stimuli manipulate distribution , abundance of insects. push means insects repelled or deterred away whatever resource being protected. pull means stimuli (semiochemical stimuli, pheromones, food additives, visual stimuli, genetically altered plants, etc.) used attract pests trap crops killed. there numerous different components involved in order implement push-pull strategy in ipm.


many case studies testing effectiveness of push-pull approach have been done across world. successful push-pull strategy developed in africa subsistence farming. successful case study performed on control of helicoverpa in cotton crops in australia. in europe, middle east, , united states, push-pull strategies used in controlling of sitona lineatus in bean fields.


some advantages of using push-pull method less use of chemical or biological materials , better protection against insect habituation control method. disadvantages of push-pull strategy if there lack of appropriate knowledge of behavioral , chemical ecology of host-pest interactions method becomes unreliable. furthermore, because push-pull method not popular method of ipm operational , registration costs higher.


effectiveness

some evidence shows alternatives pesticides can equally effective use of chemicals. example, sweden has halved use of pesticides hardly reduction in crops. in indonesia, farmers have reduced pesticide use on rice fields 65% , experienced 15% crop increase. study of maize fields in northern florida found application of composted yard waste high carbon nitrogen ratio agricultural fields highly effective @ reducing population of plant-parasitic nematodes , increasing crop yield, yield increases ranging 10% 212%; observed effects long-term, not appearing until third season of study.


however, pesticide resistance increasing. in 1940s, u.s. farmers lost 7% of crops pests. since 1980s, loss has increased 13%, though more pesticides being used. between 500 , 1,000 insect , weed species have developed pesticide resistance since 1945.








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