首页
登录
职称英语
[originaltext] Scientists have observed that plants themselves produce many
[originaltext] Scientists have observed that plants themselves produce many
游客
2023-09-01
82
管理
问题
Scientists have observed that plants themselves produce many poisonous chemicals for defence against insects. But insects have developed ways of dealing with them and, in fact, have been eating plants for about 250 million years. Now insects are using these same mechanisms to deal with man-made poisons--insecticides. This is why resistance of insects to insecticides has developed so rapidly.
What should be done? Scientists studying the problem suggest that farmers use less insecticides. At the moment, farmers regularly spray crops as a precaution against problems that are caused by large numbers of pests. They should, instead, spray only where pests have actually been seen. Secondly, farmers could use a combination of two or three insecticides at once. To survive, the insects would need to become resistant to two or more poisons at the same time.
The most surprising suggestion, perhaps, is that, at certain times of the year, farmers should actually try to attract new insects onto the crops they are trying to protect. The new insects will mate with those which survived from a certain kind of insecticide and will lessen the latter’s resistance to it.
Scientists hope that these and other measures will postpone the day when farmers and scientists will have to stand by while new super-bugs which may be resistant to all our poisons invade our farms and eat our crops.
选项
A、The use of insecticides should be limited and controlled.
B、A combination of some insecticides should be used at the same time.
C、New insects should be introduced to mate with those that have survived from a certain kind of insecticide.
D、New kinds of insecticides should be explored and developed.
答案
D
解析
转载请注明原文地址:https://tihaiku.com/zcyy/2975231.html
相关试题推荐
[originaltext]M:Goodafternoon.Iwonderifyoucouldgivemesomeinformation
[originaltext]Forcenturies,parrotshavebeenprizedpetsbecauseoftheir
[originaltext]Forcenturies,parrotshavebeenprizedpetsbecauseoftheir
[originaltext]BenjaminFranklinwasawriter,printer,inventoranddiplomat
[originaltext]BenjaminFranklinwasawriter,printer,inventoranddiplomat
[originaltext]It’scommonknowledgethatmusiccanhaveapowerfuleffect
[originaltext]It’scommonknowledgethatmusiccanhaveapowerfuleffect
[originaltext]It’scommonknowledgethatmusiccanhaveapowerfuleffect
[originaltext]W:I’dliketowelcometoour"SportsWorld"JohnnySprag,captai
[originaltext]WilliamShakespearewaschristenedinthemarkettownofStra
随机试题
WhatisNOTafeatureofthenewkaraokemachine?[originaltext]Onceasourc
[originaltext]M:Well.Itwasn’tacampundercanvaswithsingsongsroundaca
[originaltext]M:Whatmadeyoudecideonthistypeofoccupation?W:Oh,totel
设A=,B为三阶非零矩阵,且AB=O,则r(A)=_______.
下列有一项不是内伤腰痛特点A.腰部隐痛 B.病程缠绵 C.起病隐袭 D.腰
X-连锁无丙种球蛋白血症的突变基因是A.7日左右出现 B.5日左右出现 C.
患者,女性,30岁。背部肿块、红、肿、疼痛3天,寒战,发热39℃。查体:背部肿物
引起黑热病的病原虫是A.墨西哥利什曼原虫 B.杜氏利什曼原虫 C.巴西利什曼
有两个不透明的抽奖箱,里面都放有大小形状相同的红黑小球各2颗,小明和小白分别从两
关于抗震设防三个水准目标,下述说法不正确的是()。A.基本烈度、第二水准烈度
最新回复
(
0
)