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
69
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
dealing
解析
转载请注明原文地址:https://kaotiyun.com/show/spZK777K
0
大学英语六级
相关试题推荐
Ihavefoundsomearticles______theharmfuleffectsofdrinking.
Manypeoplewholiveincitiessaythattheydislikecitylife.Theysaythecityisnoisy,dirtyandcrowded.Theyaretiredof
A—WaitingandBoardingJ—CustomsDeclarationFormB—LuggageDeliveryK—QuantityAllowedtoTakeC—InspectionandQuarantineL
A—StockexchangeK—StocktransferB—BuyingandsellingstockL—StockcompanyC—StockmarketM—SharecapitalD—Currentprices
Shegottoknowtheyoungmanverywell______shehadworkedforsolong.
Ithinkwe’llbeginnow.FirstI’dliketowelcomeyouallandthankyouforyourcoming,especiallyatsuchshortnotice.Ikno
A、Hehasalreadypaidthebill.B、Hehasmovedtoanewhouse.C、Hehasbeenawayfortwoweeks.D、Hehasbeenabroadforthewh
Tobeagoodmanager,youmustbecarefultodistinctlydefinetheproperboundary(界限)betweenyourselfandyourstaff.Herear
【说明】假设你是销售部经理,写信询问对方产品信息和价格。【内容】1.在电视上看到对方的产品广告,对男女自行车及童车感兴趣;2.希望对方寄来一份产品目录和价格表;3.我司是广州最大的经销商,在10个地区设有分公司;4.如果贵司的自行车质量令人满
【说明】假设你是销售部经理,写信询问对方产品信息和价格。【内容】1.在电视上看到对方的产品广告,对男女自行车及童车感兴趣;2.希望对方寄来一份产品目录和价格表;3.我司滴广州最大的经销商,在10个地区设有分公司;4.如果贵司的自行车质量
随机试题
患者,叶某,男,67岁,退休教师,诊断“肺癌晚期”入院,入院后患者诉说胸痛难以忍受,沉默寡言,眉头紧锁,咳嗽频繁并有气喘,难以交流。请问作为主管护士:你应了解哪些主观因素影响其疼痛?
属于营养必需氨基酸的是
A.枸橼酸乙胺嗪B.吡喹酮C.阿苯达唑D.甲硝唑E.蒿甲醚
专利实施许可合同的被许可人无权允许合同规定以外的任何单位或者个人实施该专利。( )
购入材料时支付的增值税进项税额和进口关税均应计入采购成本。()
某生产企业(一般纳税人)因意外事故损失外购钢材30万元.保险公司词查后同意赔付4万元,其余损失已报经税务机关同意扣除。则该企业确定应纳税所得额时正确的有()。
地坛又名方泽坛,始建于明代,呈正方形。()
神舟七号载人飞船飞行的圆满成功告诉世界,中国不是一个只能生产鞋、袜子、打火机的国家.还可以制造宇宙飞船,“中国制造”在世界市场上的底气也因此而变强。由此可以反映出来的经济学道理是()。
你作为审计人员,去一家企业审计一笔财务资金的线索。企业的财务经理李明一直沉默不语,你怎么和李明沟通?请现场模拟。
Theconceptionofpovertyandwhatto【C1】______aboutithavechangedoverthedecades.UnderSocialDarwinismthelazyandthe【C
最新回复
(
0
)