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
13
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
mechanisms
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3636504.html
相关试题推荐
Scientistsfindthathard-workingpeoplelivemuchlongerthanaverageme
Scientistsfindthathard-workingpeoplelivemuchlongerthanaverageme
Wehaveproducedtwiceasmuchsteelthisyear______4yearsago.A、thanwedidB
Whathavepeoplediscoveredabouthobbies?Hobbiescanbeprofitableand________
Thefarmercancontinuetosupporthimselfandhisfamilyonlyifheproducesa
Scientistshavedonealotofstudytoshowthatpraiseisfar(effective)_______
Whathavepeoplediscoveredabouthobbies?Hobbiescanbeprofitableand________
ValmontIndustries,Inc.isaleadingproduceranddistributorofproduct
ValmontIndustries,Inc.isaleadingproduceranddistributorofproduct
Whathavepeoplediscoveredabouthobbies?Hobbiescanbeprofitableand_______
随机试题
Scientistshavecomeupwithatheoryforwhytimeflieswhenyonarehaving
火灾自动报警系统可以实现火灾的早期探测和报警,有效预防汽车库火灾。除敞开式汽车库
在社会心理学中,由于第一印象的形成所导致的在总体印象形成上最初获得的信息比后来获
社会工作者在策划项目时,一方面要考虑服务对象的问题和需求,另一方面要考虑资源保障
根据我国《民事诉讼法》的规定,人民法院对下列民事案件适用先予执行正确的有:(
A.防风 B.党参 C.川木香 D.银柴胡 E.知母有“珍珠盘”的药材是
会议电视会场系统的传输敷设时,当与大于5kVA的380V电力电缆平行敷设时,其最
某项目部中标一项燃气管道工程,主管道全长1.615km,设计压力为2.5MPa,
男性,病史2周,贫血伴周身出血点,浅表淋巴结不肿大,胸骨压痛(+),肝脏轻度肿大
A.骨髓巨核细胞增多,大多为颗粒型巨核细胞 B.骨髓巨核细胞数量显著减少 C
最新回复
(
0
)