VOA慢速英语2009-Development Report - Growing Crops With Less Wat

This is the VOA Special English Development Report.

Scientists are working to develop crop plants that can reduce the amount of water used for agriculture. Almost sixty percent of the world's freshwater withdrawals¹ from rivers, lakes and other water resources go toward irrigating² fields.

Scientists are using biotechnology as well as traditional breeding methods to develop water-saving crops to feed a growing world.
　
Thomas Carter

Thomas "Tommy" Carter is a plant scientist in North Carolina. He works for the Agricultural Research Service in the United States Department of Agriculture. He leads Team Drought, a group of researchers at five universities. They have been using conventional breeding methods to develop and test soybeans that can grow well under dry conditions.

Tommy Carter started working on drought-resistant soybeans in nineteen eighty-one. His research has taken him as far as China, where soybeans have been grown for thousands of years.

Farmers in the United States, however, have grown soybeans for only about a century. Tommy Carter says the soybeans they grow are for the most part genetically⁴ similar. More differences, or diversification⁵, could better protect crops against climate changes that can reduce production. Those changes include water shortages which could increase from global warming.

The Agriculture Department has a soybean germplasm collection, a collection of genetic³ material passed from one generation to the next. Members of Team Drought studied more than two thousand five hundred examples from the collection.

They looked at ones from the ancestral home of soybeans, Asia. They searched for germplasms that could keep plants from weakening and wilting⁶ during hot, dry summers in the United States.

Tommy Carter says they found only five. But these slow-wilting lines, he says, produce four to eight bushels more than normal soybeans under drought conditions. The yield depends on location and environment.

Scientists are also working on other plants that either use less water or use it better, or both. For example, companies like Monsanto, DuPont and Syngenta have been developing corn with reduced water needs. Monsanto expects to be ready in a few years to market its first corn seeds genetically engineered to resist drought.

And that's the VOA Special English Development Report, written by Jerilyn Watson. You can find transcripts⁷, MP3s and podcasts of our reports -- and write comments -- at voaspecialenglish.com. I'm Steve Ember.

1 withdrawals   

n.收回，取回，撤回( withdrawal的名词复数 )；撤退，撤走；收回[取回，撤回，撤退，撤走]的实例；推出（组织），提走（存款），戒除毒瘾，对说过的话收回，孤僻

参考例句：

• He has made several withdrawals from his bank account. 他从银行账户上提了几次款。 来自《简明英汉词典》
• It is not the bank's policy to deduct interest on withdrawals. 提款需扣除利息这并非是本银行的政策。 来自辞典例句

2 irrigating   

灌溉( irrigate的现在分词 )； 冲洗（伤口）

参考例句：

• Derrick and I have been laying out the system of irrigating ditches. 德里克跟我在一起修建那个灌溉网。
• He had been in command at the irrigating ditch the day before. 上一天，在灌溉渠边，是他担任指挥的。

3 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。

4 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

5 diversification   

n.变化，多样化；多种经营

参考例句：

• The seminar was to discuss diversification of agriculture. 该研讨会讨论的是农业多种经营。 来自辞典例句
• Firm diversification is increasingly achieved by the means of takeover and merger. 通过接管和兼并，厂商经营范围日益多样化。 来自辞典例句

6 wilting   

萎蔫

参考例句：

• The spectators were wilting visibly in the hot sun. 看得出观众在炎热的阳光下快支撑不住了。
• The petunias were already wilting in the hot sun. 在烈日下矮牵牛花已经开始枯萎了。

7 transcripts   

n.抄本（ transcript的名词复数 ）；转写本；文字本；副本

参考例句：

• Like mRNA, both tRNA and rRNA are transcripts of chromosomal DNA. tRNA及rRNA同mRNA一样，都是染色体DNA的转录产物。 来自辞典例句
• You can't take the transfer students'exam without your transcripts. 没有成绩证明书，你就不能参加转学考试。 来自辞典例句