VOA慢速英语2009年-Agriculture Report - With Resistant Crops,

This is the VOA Special English Agriculture Report.

Plant breeders and genetic² engineers keep working to give crops the strength to resist threats like insects, diseases, droughts or floods.

But before you can resist a threat, you need to understand it.

We told you last week about a newly completed genetic map of the organism that causes late blight³. That disease led to starvation in Ireland from potato shortages in the middle of the eighteen hundreds. The new genome could lead to better ways to protect potatoes, tomatoes and other crops.

Science may supply a stronger crop. Yet that does not always guarantee demand.

Nik Grunwald from the United States Agriculture Department worked on the international team that completed the genome. He says it is possible to grow potatoes that resist late blight. But these may not look like Russet potatoes. And most American farmers grow Russets because, as Nik Grunwald puts it, "that is where the demand is."

Another example of scientific progress involves a natural bacterium⁴ known as Bt. Bt is used as a pesticide⁵ to fight cotton bollworms, corn borers and other pests. Scientists have found a way to grow cotton plants that contain a Bt gene¹, reducing the need for pesticides⁶. But sometimes, when one problem gets solved, another one appears.

In China, some farmers and researchers blame a decrease in pesticide use for an increase in pests unaffected by Bt. Also, there are concerns that some organisms could begin to resist the plants designed to resist them.

And scientists are reporting this week on what they call the "indirect costs" of a virus-resistance gene in Cucurbita. This is the species of squash that includes pumpkins⁷ and gourds⁸. The scientists say virus-resistant transgenic squash are grown throughout the United States and much of Mexico.

The genetically⁹ engineered squash are usually larger and healthier than wild squash. But a three-year study showed that beetles¹⁰ like to feed more on the transgenic plants, increasing cases of wilt¹¹ disease. The report by a team from the United States and China appears in the Proceedings¹² of the National Academy of Sciences.

The researchers point out that gene flow between crops and their wild relatives is common and difficult to contain. They note concerns that wild plants could, as a result, gain genetically engineered resistances. And these could affect the natural balance in their environment.

And that's the VOA Special English Agriculture Report, written by Jerilyn Watson. I'm Bob Doughty¹³.

1 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

2 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

3 blight   

n.枯萎病；造成破坏的因素；vt.破坏，摧残

参考例句：

• The apple crop was wiped out by blight.枯萎病使苹果全无收成。
• There is a blight on all his efforts.他的一切努力都遭到挫折。

4 bacterium   

n.(pl.)bacteria 细菌

参考例句：

• The bacterium possibly goes in the human body by the mouth.细菌可能通过口进入人体。
• A bacterium is identified as the cause for his duodenal ulcer.一种细菌被断定为造成他十二指肠溃疡的根源。

5 pesticide   

n.杀虫剂，农药

参考例句：

• The pesticide was spread over the vegetable plot.菜田里撒上了农药。
• This pesticide is diluted with water and applied directly to the fields.这种杀虫剂用水稀释后直接施用在田里。

6 pesticides   

n.杀虫剂( pesticide的名词复数 )；除害药物

参考例句：

• vegetables grown without the use of pesticides 未用杀虫剂种植的蔬菜
• There is a lot of concern over the amount of herbicides and pesticides used in farming. 人们对农业上灭草剂和杀虫剂的用量非常担忧。 来自《简明英汉词典》

7 pumpkins   

n.南瓜( pumpkin的名词复数 )；南瓜的果肉，南瓜囊

参考例句：

• I like white gourds, but not pumpkins. 我喜欢吃冬瓜，但不喜欢吃南瓜。 来自《简明英汉词典》
• Then they cut faces in the pumpkins and put lights inside. 然后在南瓜上刻出一张脸，并把瓜挖空。 来自英语晨读30分（高三）

8 gourds   

n.葫芦( gourd的名词复数 )

参考例句：

• Dried gourds are sometimes used as ornaments. 干葫芦有时用作饰品。 来自《简明英汉词典》
• The villagers use gourds for holding water. 村民们用葫芦盛水。 来自《简明英汉词典》

9 genetically   

adv.遗传上

参考例句：

• All the bees in the colony are genetically related. 同一群体的蜜蜂都有亲缘关系。
• Genetically modified foods have already arrived on American dinner tables. 经基因改造加工过的食物已端上了美国人的餐桌。 来自英汉非文学 - 生命科学 - 基因与食物

10 beetles   

n.甲虫( beetle的名词复数 )

参考例句：

• Beetles bury pellets of dung and lay their eggs within them. 甲壳虫把粪粒埋起来，然后在里面产卵。 来自《简明英汉词典》
• This kind of beetles have hard shell. 这类甲虫有坚硬的外壳。 来自《现代汉英综合大词典》

11 wilt   

v.(使)植物凋谢或枯萎；(指人)疲倦，衰弱

参考例句：

• Golden roses do not wilt and will never need to be watered.金色的玫瑰不枯萎绝也不需要浇水。
• Several sleepless nights made him wilt.数个不眠之夜使他憔悴。

12 proceedings   

n.进程，过程，议程；诉讼(程序)；公报

参考例句：

• He was released on bail pending committal proceedings. 他交保获释正在候审。
• to initiate legal proceedings against sb 对某人提起诉讼

13 doughty   

adj.勇猛的，坚强的

参考例句：

• Most of successful men have the characteristics of contumacy and doughty.绝大多数成功人士都有共同的特质：脾气倔强，性格刚强。
• The doughty old man battled his illness with fierce determination.坚强的老人用巨大毅力与疾病作斗争。