VOA标准英语2010年-Scientists Unravel Chocolate's Genetic

Chocolate lovers around the world take note: two separate groups of scientists have unraveled the genetic¹ code of your favorite sweet. It's good news for the millions of small farmers in Africa, Asia and Latin America whose livelihoods² depend on the seeds of the cacao tree.

Candy is serious business. The world's top-10 confectioners sold more than $40 billion of it in 2005.

But many of the more than five million farmers worldwide who produce cocoa, the main ingredient in chocolate, are living in poverty.

Yield gap

One reason for that is that their farms are not very productive, according to Howard-Yana Shapiro, head of plant research for the US-based candy giant, Mars Inc. Shapiro says the average West African cacao tree farmer produces only about 400 kilograms of cocoa beans per hectare.

 
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Each year farmers lose about a third of their harvest to pests and fungal diseases. The genome data is expected to help relieve the problem.
"There's a yield potential of maybe 4,000 kilos, 10 times what the average is in West Africa," he says. "We saw the disparity."

To reduce that disparity, Mars helped fund a project to sequence the genome of the cacao tree. The Mars project sequenced the most common variety. French researchers led a separate effort focusing on the high-quality Criollo variety.

Cocoa disease

Genome data is expected to help with some of the most common problems facing cacao growers. Each year farmers lose about a third of their harvest to pests and fungal diseases, says Bill Guyton, president of the World Cocoa Foundation, an industry-sponsored group promoting sustainable cocoa farming.

"This type of program we feel is going to be very beneficial in helping³ to breed trees that are more tolerant or resistant⁴ against some of the fungal pests," he says. And with better productivity, he adds, farmers can earn more money and improve their social conditions.

 
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Many of the five million farmers worldwide who produce cocoa, the main ingredient in chocolate, are living in poverty.
Mars team leader Shapiro says it's a win-win both for the company and for cocoa farmers.

"We want to be in business sustainably in the future. We want to have certified⁵ cocoa that is sustainably grown. We want the farmers to have a sustainable life. We don't want them to all have to move to the city."

The genome data will be publically available without restrictions⁶ or patents. Shapiro expects improved cacao trees to start reaching farmers in about three years.
 

1 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。

2 livelihoods   

生计，谋生之道( livelihood的名词复数 )

参考例句：

• First came the earliest individualistic pioneers who depended on hunting and fishing for their livelihoods. 走在最前面的是早期的个人主义先驱者，他们靠狩猎捕鱼为生。 来自英汉非文学 - 政府文件
• With little influence over policies, their traditional livelihoods are threatened. 因为马赛族人对政策的影响力太小，他们的传统生计受到了威胁。

3 helping   

n.食物的一份&adj.帮助人的，辅助的

参考例句：

• The poor children regularly pony up for a second helping of my hamburger. 那些可怜的孩子们总是要求我把我的汉堡包再给他们一份。
• By doing this, they may at times be helping to restore competition. 这样一来, 他在某些时候,有助于竞争的加强。

4 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。

5 certified   

a.经证明合格的；具有证明文件的

参考例句：

• Doctors certified him as insane. 医生证明他精神失常。
• The planes were certified airworthy. 飞机被证明适于航行。

6 restrictions   

约束( restriction的名词复数 )； 管制； 制约因素； 带限制性的条件（或规则）

参考例句：

• I found the restrictions irksome. 我对那些限制感到很烦。
• a snaggle of restrictions 杂乱无章的种种限制