首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Scientists have discovered that plants themselves produce many poisonous chemicals for (36)______ against insects. But insects h
Scientists have discovered that plants themselves produce many poisonous chemicals for (36)______ against insects. But insects h
admin
2009-04-23
40
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
resistance
解析
转载请注明原文地址:https://jikaoti.com/ti/F77MFFFM
0
大学英语六级
相关试题推荐
Weappreciatethegoodqualityofyourproducts,butunfortunatelyyourpricesappeartobeonthehighside.
(Website)VisitorAgreementStatesman.comisprovidedtoyoubyCoxTexasNewspapers.Thisvisitoragreementislegallybind
A、Allstaff.B、Youngworkers.C、Newemployees.D、Departmentmanagers.C本题询问这个计划的培训对象。根据对话中男士所说的“我们想为新员工(for1thenewemployees)制
Oneyearagotoday,youngJim’sparentshadaveryserioustalkwithhim.Theycomplainedthathehadspentalotoftimebefore
BetteryourEnglishandcustomerserviceskillsinabettercareerJoinourfastexpandingteamandyouwillbeinvolvedin
Directions:Thispartistotestyourabilitytodopracticalwriting.YouarerequiredtowriteaNoticeaccordingtothefollowi
A、Thegoodsareoutofstock.B、Sheismovingtoanothercity.C、Thesalesseasoniscomingsoon.D、Sheisafraidthepricewill
Whenreturningproductstous,youmusttakecaretoseethattheyarereceivedbyusandnotdamagedintransit.
A(detail)______listofallpatientswaskeptbythenursingstaffinthehospital.
A、Hethinksflieswilltakeovertheearth.B、Hethinkshumanwilldieoffquitesoon,C、Hethinksmassdiseasecouldbethenex
随机试题
PowerPoint中,在当前编辑的演示文稿中插入新幻灯片应使用()
人民群众对历史的创造作用总是受到社会历史条件的制约,其根本的条件是()
周围神经损伤的康复时机选择应在
不必经过肠激酶或胰蛋白酶激活的胰腺酶是
烟囱上采用圆钢做避雷器,其直径不应小于()mm。
在施工成本控制的步骤中,( )是施工成本控制工作的核心,( )是施工成本控制中最具实质性的一步。
投保普通财险的某固定资产在保险事故中部分灭失,则其赔偿方式可能为()。
2017年12月10日,甲公司因合同违约而涉及一桩诉讼案件。根据甲公司的法律顾问判断,最终的判决很可能对甲公司不利。2017年12月31日,甲公司尚未接到法院的判决,因诉讼须承担的赔偿金额无法准确地确定。不过,据专业人士估计,赔偿金额可能在200万元至22
下列选项中哪个是社区工作者在社区工作中与居民接触的常用工作技巧?( )。
设求[img][/img]
最新回复
(
0
)