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
3
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
rapidly
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3636506.html
相关试题推荐
ValmontIndustries,Inc.isaleadingproduceranddistributorofproduct
ValmontIndustries,Inc.isaleadingproduceranddistributorofproduct
Whathavepeoplediscoveredabouthobbies?Hobbiescanbeprofitableand_______
Whathavepeoplediscoveredabouthobbies?Hobbiescanbeprofitableand_______
Whathavepeoplediscoveredabouthobbies?Hobbiescanbeprofitableand_______
Scientistsfindthathard-workingpeoplelivemuchlongerthanaveragemena
Scientistsfindthathard-workingpeoplelivemuchlongerthanaveragemena
Scientistsfindthathard-workingpeoplelivemuchlongerthanaveragemena
Bytheendoflastmonth,ourfactory(produce)________3,000motors.hadproduc
Thelearnedthinkthemselvessuperiortothecommonherd.A、有学问的人认为他们比普通群众高明。B、知
随机试题
Cigarettesaregoodforyourthroat,accordingtoadvertisementsfromhalfa
A.E大调 B.G大调 C.e旋律小调 D.b旋律小调
关于衣原体,正确的是A:能用培养基培养 B:细胞内寄生 C:含一种类型核酸
客票根据航程分为()A.单程客票 B.联程客票 C.来回程客票 D.环程客
A.90棵 B.93棵 C.96棵 D.99棵
对于基金信息披露重大性的界定,我国仅采用“影响投资者决策”标准。()
客户违约给商业银行带来的债项损失包括两个层面,分别是()。 A.金融缺失和财
在氢化可的松结构上,将6α、9α位引入氟原子,在16、17α位引入缩酮结构,并将
某企业发生一起桥机起吊事故。事故经过是:一台30t/5t桥机在对一件尺寸为830
男,25岁,突感上腹部剧痛。检查:血压130/80mmHg,脉搏110次/分,板
最新回复
(
0
)