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
28
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://www.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
IntheUnitedStatesandinmanyothercountriesaroundtheworld,thereare
当控制区面积为5~10km2时,首级控制等级为( )。A.四等以上控制网 B
SNMPc支持各种设备访问方式,在SNMPc支持的设备访问方式中,只是用于
固定资产投资的资金来源包括()。A.上年末结余资金 B.本年度拨人资金 C.
某混凝土试块强度值不满足规范要求,但经法定检测单位对混凝土实体强度经过法定检测后
AA BB CC DD
( )状态下,人往往会出现“意识狭窄”现象。A.热情 B.应激 C
怕货币贬值,存钱会带来损失;花钱买东西,又没值得买的东西时的动机冲突属于()。
下列要求中,不符合安全部件安装验收的是()。A.限速器动作速度整定封记必须
胆汁质气质的人,其高级神经活动类型属于() A.强、均衡而灵活的活泼型 B.
最新回复
(
0
)