首页
登录
职称英语
[originaltext] Scientists have observed that plants themselves produce many
[originaltext] Scientists have observed that plants themselves produce many
游客
2024-02-17
50
管理
问题
Scientists have observed 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-insecticide.This is why resistance of insects to insecticide has developed so rapidly.What should be done?Scientists studyilg the problem suggest that farmers use less insecticide.At the moment,famlers 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 jnsecticide at once.To survive,the insects would need to become resistant to two or more poisons at the same time.The most surprising suggestion,perhaps,perhaps,is that,at certain times of the year,famers should actually try to attract new insects onto the crops they are trying to protect.The new insects will mate with those which survived from a certain kind of insecticide and will lessen the latter’s resistance to it.
Scientists 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 our poisons invade our farms and devour our crops.
选项
A、There are 250 million plants eaten by insects.
B、There are fewer plants than 250 million years ago.
C、They have their way of guarding against insects.
D、They have a better immune system than before.
答案
C
解析
短文开头就说到,科学家发现庄稼自身可以产生许多有害的化学物质来抵御昆虫的侵害,即庄稼自有抵制昆虫侵害的方法,C与此含义相符,故正确。
转载请注明原文地址:http://tihaiku.com/zcyy/3459111.html
相关试题推荐
[originaltext]Ofallthestarsthesunisthenearesttotheearth.Million
[originaltext]Ofallthestarsthesunisthenearesttotheearth.Million
[originaltext]Manychangesaretakingplaceinthewayinwhichmenandwom
[originaltext]Pete:HeyMarkus.IhaveaquestionI’dliketoaskyou.Markus:
[originaltext]W:Whodoyouthinkshouldgetthejob?HowaboutMr.Becket?M:
[originaltext]W:Whodoyouthinkshouldgetthejob?HowaboutMr.Becket?M:
[originaltext]W:Whodoyouthinkshouldgetthejob?HowaboutMr.Becket?M:
[originaltext]W:Whodoyouthinkshouldgetthejob?HowaboutMr.Becket?M:
[originaltext]Togetadriver’slicense,youmusttakeaseriesoftests.T
[originaltext]Togetadriver’slicense,youmusttakeaseriesoftests.T
随机试题
[originaltext]W:So,oneofthethingsthatIreallyhavetroubleunderstanding
TheHappinessEffect[A]Thenexttimeyougettheflu,t
[originaltext]W:Charles,amongotherthings,youareregardedasoneoftheAm
[originaltext]W:Excuseme,Professor.Ihaveaquestion.I’mworriedaboutmy
下列选项中,对于民间舞蹈“即兴性”的正确理解是:()A.民间舞蹈的表演程式规范
下表为某公司四个部门2009年全年的营销总费用,以及营销总费用占总销售额的比例。
房地产开发程序中建设阶段的工作不包括( )。A.建设招标 B.成本管理 C
证券公司独立董事在任期内辞职或被免职的,独立董事本人和证券公司应当分别向()和股
某股份制商业银行2012年末资产余额9341亿元,贷款余额5657亿元,资本净额
患者男,70岁。右腹股沟区可复性肿块4年,不能还纳8小时,伴腹痛。诊断右腹股沟斜
最新回复
(
0
)