首页
登录
职称英语
What conclusion can be drawn from the scientists’ observation? [br] [originalte
What conclusion can be drawn from the scientists’ observation? [br] [originalte
游客
2024-11-01
1
管理
问题
What conclusion can be drawn from the scientists’ observation? [br]
Scientists have discovered that plants themselves pro- duce 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 use less 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 at-tract 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.
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
A、Farmers should use less insecticides.
B、Farmers should use a combination of two or three insecticides at once.
C、At certain times of the year, farmers should actually try to attract new insects onto the crops they are trying to protect.
D、Farmers should regularly spray crops as a precaution against problems that are caused by large numbers of pests.
答案
D
解析
“They should,instead,spray only where pests have actually been seen.”,“Secondly,farmers could use a combination of two or three insecticides at once.”,“farmers should actually try to attract insects onto the crops they are trying to protect”选项A,B,C在课文中都有提
转载请注明原文地址:https://tihaiku.com/zcyy/3826125.html
相关试题推荐
WhatisthepurposeofthemeetinginLuxembourg?[br][originaltext]TheW
WhatisthepurposeofthemeetinginLuxembourg?[br][originaltext]TheW
WhatisthepurposeofthemeetinginLuxembourg?[originaltext]TheWestern
PresidentProsperAvrilhasbeenarrestedonchargeof______.[br][originalte
PresidentProsperAvrilhasbeenarrestedonchargeof______.[br][originalte
WherewasSberrillgoingwhenFillmether?[br][originaltext]M:Hi,Sherril.
WherewasSberrillgoingwhenFillmether?[originaltext]M:Hi,Sherril.W:Hel
Whatelectionarethespeakersdiscussing?[originaltext]M:Comeon,Jully,how’
Whatdoesthewomanmeanbysaythathermotherwaslikethepope?[originaltext
[originaltext]Balloonshavebeenusedforsportsforaboutonehundredyea
随机试题
[originaltext]Manychildrenfirstlearnthevalueofmoneybyreceivinganallo
"Professor’sOffice"[img]2012q1/ct_etoefm_etoeflistz_1468_20121[/img][br]Whyd
A. B. C. D.
低渗性脱水病人血浆渗透压是A.
工地试验室应制定样品管理制度,对样品的()等全过程实施严格的控制和管理。A
李某,女,19岁。有痫病史3年。平素头晕头痛,痛有定处,颜面口唇青紫,舌质暗红有
2020年12月,中国新能源汽车生产销售双增长,产销双双超过20万辆,再创历史新
下列各项组织职能中,属于关键职能的是()。A.售后服务 B.市场营销 C.
如果支护结构破坏,土体失稳或过大变形对基坑周边环境及地下结构施工影响一般,其基坑
中国多样化的地理环境和气候,日出而作,日落而息,人们春种,秋收,夏耕,冬藏,四季
最新回复
(
0
)