英语听力精选进阶版 13926

American superweeds

Summary

20 September 2012

Farmers all over the US are facing a growing challenge from so-called 'superweeds' that are resistant¹ to chemical weed killers³. Because genetically-modified crops are designed to be protected from one type of weed killer², farmers have become over-reliant on using this chemical on their crops. However, some weeds have developed a natural resistance to it and are spreading rapidly. Scientists have designed a new type of GM crop which has resistance to more than one chemical, to aid farmers in killing⁴ the weeds.

Reporter:

Matt McGrath

Report

Nebraska farmer Jeremy Leech⁵ is happy to be harvesting his corn this year. In 2011 he spent around $7,500 on herbicides that completely failed to stem the weeds strangling his crops.

To overcome the problem of resistance, Dow Agrosciences are now seeking a licence to plant a new type of GM that has resistance to Roundup, and another older chemical called 2,4-D. 2,4-D is best known as a component⁶ of Agent Orange, a defoliant sprayed extensively during the Vietnam war. But farmers like Jeremy Leech are worried that if the new GM is overused, weeds might well become resistant to it as well.

Jeremy Leach⁷, farmer:

I think 2,4-D will work fine but I’m afraid, nervous, of what’s going to happen, four or five years down the road now if we keep using 2,4-D like we’re going to have the same problem we are now with Roundup.

Dow are likely to get the go-ahead to plant the new GM next spring. But, surprisingly, the company stresses that chemicals alone won't beat the weeds. As well as sprays, they say, growers now need to incorporate older weed control techniques often used by organic farmers.

1 resistant   

adj.(to)抵抗的，有抵抗力的

参考例句：

• Many pests are resistant to the insecticide.许多害虫对这种杀虫剂有抵抗力。
• They imposed their government by force on the resistant population.他们以武力把自己的统治强加在持反抗态度的人民头上。

2 killer   

n.杀人者，杀人犯，杀手，屠杀者

参考例句：

• Heart attacks have become Britain's No.1 killer disease.心脏病已成为英国的头号致命疾病。
• The bulk of the evidence points to him as her killer.大量证据证明是他杀死她的。

3 killers   

凶手( killer的名词复数 )； 消灭…者； 致命物； 极难的事

参考例句：

• He remained steadfast in his determination to bring the killers to justice. 他要将杀人凶手绳之以法的决心一直没有动摇。
• They were professional killers who did in John. 杀死约翰的这些人是职业杀手。

4 killing   

n.巨额利润；突然赚大钱，发大财

参考例句：

• Investors are set to make a killing from the sell-off.投资者准备清仓以便大赚一笔。
• Last week my brother made a killing on Wall Street.上个周我兄弟在华尔街赚了一大笔。

5 leech   

n.水蛭，吸血鬼，榨取他人利益的人；vt.以水蛭吸血；vi.依附于别人

参考例句：

• A leech is a small blood-sucking worm and usually lives in water.水蛭是一种小型吸血虫，通常生活在水中。
• One-side love like a greedy leech absorbed my time and my mirth.单相思如同一只贪婪的水蛭，吸走了我的时间和欢笑。

6 component   

n.组成部分，成分，元件；adj.组成的，合成的

参考例句：

• Each component is carefully checked before assembly.每个零件在装配前都经过仔细检查。
• Blade and handle are the component parts of a knife.刀身和刀柄是一把刀的组成部分。

7 leach   

v.分离，过滤掉；n.过滤；过滤器

参考例句：

• Liquid water can leach soluble materials from the interface.液态水能够从界面溶解出可溶性物质。
• They believe that the humic materials are leached from decaying plant materials.他们认为腐植物料是从腐烂的植物体浸沥而来。