首页
登录
职称英语
Scientists have discovered that plants themselves produce many poisonous che
Scientists have discovered that plants themselves produce many poisonous che
游客
2024-06-16
38
管理
问题
Scientists have discovered that plants themselves produce many poisonous chemicals for (36)______ against insects. But insects have developed ways of (37)______ with them and, in fact, have been eating plants for about 250 million years. Now insects are using these same (38)______ to deal with man-made poisons—insecticides. This is why (39)______ of insects to insecticides has developed so (40)______.
What should be done? Scientists studying the problem suggest that farmers use less insecticides. At the moment, farmers (41)______ spray crops as a (42)______ against problems that are caused by large number of pests. They should, instead, spray only where pests have actually been seen. Secondly, farmers could use a (43)______ of two or three insecticides at once. (44)____________.
The most surprising suggestion, perhaps, is that at certain times of the year, (45)____________. The new insects will mate with those which survived from a certain kind of insecticide and will lessen the latter’s resistance to it.
(46)____________ , which may be resistant to all poisons invade our farms and devour our crops.
[br]
Scientists have discovered that plants themselves produce many poisonous chemicals for defense 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 useless 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 insecticides at the same time.
The most surprising suggestion, perhaps, is that at certain times of the year, farmers should actually try to attract insects onto the crops they are trying to protect. The new insects will mate with those which survived from a certain kind of insecticide anti will lessen the latter’s resistance to it.
Scientist 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 poisons invade our farms and devour our crops.
选项
答案
regularly
解析
转载请注明原文地址:http://tihaiku.com/zcyy/3636507.html
相关试题推荐
[originaltext]Ateamofscientistsrecentlybeganaprojecttomeasurethe
[originaltext]Ateamofscientistsrecentlybeganaprojecttomeasurethe
[originaltext]Ateamofscientistsrecentlybeganaprojecttomeasurethe
Scientistshavediscoveredthatplantsthemselvesproducemanypoisonousche
Scientistshavediscoveredthatplantsthemselvesproducemanypoisonousche
Scientistshavediscoveredthatplantsthemselvesproducemanypoisonousche
Scientistshavediscoveredthatplantsthemselvesproducemanypoisonousche
[originaltext]Onewaythatscientistslearnaboutmanisbyanimals,sucha
[originaltext]Onewaythatscientistslearnaboutmanisbyanimals,sucha
[originaltext]Onewaythatscientistslearnaboutmanisbyanimals,sucha
随机试题
PASSAGETHREE[br]WhatdoestheeconomicconstructionofKazakhstanrelyon?Oil
[originaltext]M:Shanika,thanksforjoiningustoday!W:Mypleasure.M:First
[originaltext]Karenhaswrittenatouchingopenlettertoayoungmothershewi
Namedafteranex-GovernorofNewSouthWales,SydneyistheState’scapital
女性,28岁,痛经3年,进行性加重,GP。妇科检查:子宫正常大小,活动差,子宫
患者,女性,40岁。甲状腺肿物5年,伴声音嘶哑3个月,不能平卧,既往有气管炎病史
常用于过敏性试验的注射途径是A:皮下注射 B:皮内注射 C:脊椎腔注射 D
下列设备中,属于输出设备的是()。 A.显示器B.键盘 C.鼠标D.手
A.直接盖髓术 B.间接盖髓术 C.活髓切断术 D.干髓术 E.根管治疗
某白酒生产企业为增值税一般纳税人,2020年1月份销售白酒2吨,取得含税销售额2
最新回复
(
0
)