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
27
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.
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
defense
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3020236.html
相关试题推荐
Scientistsareeagertotalkwithotherscientistsworkingonsimilarproblem.A、
Thescientistswantedtokeeppeople______aboutthebreakthroughintheirexpe
Whatproductdoesthecompanyproduce?_______.[br][originaltext]Goodmor
Womenaregoingafterequalitythemselvesinsteadofwaitingfororganizationst
Scientistsareeagertotalkwithotherscientistsworkingonsimilarproblem.A、
Itwasnotuntilthenextmorning______theparentsdiscoveredthechildrendid
Scientistsfindthathard-workingpeoplelivemuchlongerthanaveragemena
Scientistsfindthathard-workingpeoplelivemuchlongerthanaveragemena
Scientistsfindthathard-workingpeoplelivemuchlongerthanaveragemena
Scientistsfindthathard-workingpeoplelivemuchlongerthanaveragemena
随机试题
Recently,ImadeatriparoundEuropewithmyfamilyandittookbreathawayto
Tomhopestobedischargedfromthehospitaltomorrow.Theunderlinedpartmeans
A.limitedB.distinguishC.unlikeD.particularE.triggerF.inefficientG.c
TherearemorethanfortyuniversitiesinBritain--nearlytwiceasmanyasi
如图所示的四个实例中,为了减小压强的是:()A. B. C. D.
我国肾移植最早是在哪一年开展的A.1950 B.1960 C.1965 D
开放性气胸的特殊病理变化是()。A.健侧肺受压 B.小肺泡破裂 C.伤侧肺萎
根据《最高人民法院关于审理物业服务纠纷案件具体应用法律若干问题的解释》,下列情形
(2020年真题)下列各项中,股份有限公司回购股票支付的价款低于股票面值总额的差
若钢芯铝绞线的铝钢比为10,其单一的弹性系数分别为181000N/mm2(钢)和
最新回复
(
0
)