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
2023-09-16
62
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
combination
解析
转载请注明原文地址:https://www.tihaiku.com/zcyy/3020243.html
相关试题推荐
Scientistsfindthathard-workingpeoplelivemuchlongerthanaveragemena
Scientistsfindthathard-workingpeoplelivemuchlongerthanaveragemena
Scientistsfindthathard-workingpeoplelivemuchlongerthanaveragemena
Bytheendoflastmonth,ourfactory(produce)______3000motors.hadproduced本题考
Scientistsshouldbekept_____ofthelatestdevelopmentsintheirresearcharea
Thescientistswantedtokeeppeople_____aboutthebreakthroughintheirexper
Whathavepeoplediscoveredabouthobbies?Hobbiescanbeprofitableand______.
Whathavepeoplediscoveredabouthobbies?Hobbiescanbeprofitableand______.
Whathavepeoplediscoveredabouthobbies?Hobbiescanbeprofitableand______.
Scientistshavedonealotofstudytoshowthatpraiseisfar(effective)______
随机试题
【B1】[br]【B5】A、digitsB、formsC、devicesD、menusC从前面的electronic可知,此处只能选devices
维拉帕米的药理作用是A.增加心肌收缩力 B.直接抑制Na内流 C.降低窦房结
检索国内外标准文献信息的工具很多,主要分为纸质版、光盘版和网络版3种。()
在进行财务管理体制设计时,应当遵循的原则有()。A.明确分层管理思想 B.与现
服务器的部署是网络规划的重要环节。某单位网络拓扑结构如图3-2所示,需要部署V
(2020年真题)为了帮助精神病患者老张出院之后在社区进行康复,社会工作者小王来
对于肝病,“见其色而不得其脉”是指 A.面色青,脉浮 B.面色青,脉缓 C
直接作用于中枢神经系统,使之兴奋或抑制,连续使用后能产生身体依赖性的药品是A.麻
信用货币具有强制性表现为()。A.与黄金完全脱离 B.信用货币实际上是
患儿,男,3岁,生后半年发现智能落后,反复惊厥,且尿有鼠尿味,体检:目光呆滞,毛
最新回复
(
0
)