VOA慢速英语2015 改变植物基因或能增加产量

Changing Gene¹ in Plant Could Yield More Crops 改变植物基因或能增加产量

Plants have a “biological clock” that tells them when to produce leaves, seeds and other growth. A new study says understanding that clock may help scientists develop crops that can feed a growing population in an increasingly warmer world.

Rob McClung is a scientist at Dartmouth College. He says scientists need to create ways to feed the nearly 10 billion people who will be living on Earth by the middle of the century.

He says estimates show that there will need to be an increase in the world food supply of about 50 to 60 percent in the next thirty-five years.

“And we're worried that the things that we've done to increase agricultural productivity may be becoming exhausted².”

To find new ways to increase productivity, Mr. McClung examined the biological clocks of plants. He learned that different genes³ in plants affect the plant's clock.

He published his findings in the Proceedings⁴ of the National Academy of Sciences. He says he identified a gene called GIGANTEA in a common species of the plant called field mustard.

He discovered that the speed of the gene’s development can affect when the plant produces. Mr. McClung says the gene also affects how the plant deals with extreme cold and high levels of salt.

“We want to be able to predict if you do this to the clock, you will do this to crop yield.”

He says he hopes his research will give plant developers a molecular⁵ tool they can use to create a plant that can accept a higher level of salt or grow in a colder environment than usual.

“…we think that by manipulating the plant clock, we will be able to make plants that are better in tune⁶ with their environment and able to perform more effectively.”

Experts say the current growth in the production of the world’s major food crops -- corn, rice, wheat and soybeans -- will not be enough to feed the 9.5 billion people who will be living on Earth in 2050.  

Words in This Story

exhausted – adj. completely used up

biological clock – n. a system that controls natural processes such as waking, sleeping and aging

yield –  n. the amount of something that is produced by a plant or farm

manipulate – v. to use or change for a particular purpose

in tune with  – (idiom; figurative) to be in agreement with someone or something

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 exhausted   

adj.极其疲惫的，精疲力尽的

参考例句：

• It was a long haul home and we arrived exhausted.搬运回家的这段路程特别长，到家时我们已筋疲力尽。
• Jenny was exhausted by the hustle of city life.珍妮被城市生活的忙乱弄得筋疲力尽。

3 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

4 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

5 molecular   

adj.分子的；克分子的

参考例句：

• The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
• For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。

6 tune   

n.调子；和谐，协调；v.调音，调节，调整

参考例句：

• He'd written a tune,and played it to us on the piano.他写了一段曲子，并在钢琴上弹给我们听。
• The boy beat out a tune on a tin can.那男孩在易拉罐上敲出一首曲子。