VOA慢速英语20061128a

AGRICULTURE REPORT - Genetic¹ Map Could Point Way to an Improved Honey BeeBy Jerilyn Watson

Broadcast: Tuesday, November 28, 2006

This is the VOA Special English Agriculture Report.




Scientists now have a genetic map of the world's most important insect -- important to the food supply. The results showing the order, or sequence, of ninety-eight percent of the honey bee genome created a buzz of excitement. Understanding how a honey bee is designed should help scientists produce stronger bees.

Honey bees are the world's major source of pollination² for food, fiber³ and oilseed crops. Bees gather nectar from flowers; the liquid gives them food and material to make honey. As they land, their bodies pick up and drop off fine particles of pollen⁴. Most flowering plants need pollination to reproduce.

But Kevin Hackett, an official at the United States Department of Agriculture, noted⁵ that the world's honey bee population is decreasing. He called the sequencing of its genome a powerful tool for fighting back against the causes.

One cause is the varroa mite⁶ which can kill young bees even before they leave their eggs. Another is the tracheal mite which nests in the breathing tube of adult bees.

Some people think that insect poisons have also played a part in reducing bee populations.

Experts say honey bees are responsible for as much as twenty thousand million dollars worth of food production in the United States alone. But scientists have estimated that the bee population in the United States fell by fifty percent over the past half-century.

The main results of the Honey Bee Genome Sequencing Project Consortium appeared in the journal Nature. This international team is led by human-genome researchers at Baylor College of Medicine in Houston, Texas. Related reports appeared in other publications.

Like humans, bees have genes⁷ that give them a sense of day and night. Scientists believe this helps honey bees gather food.

Bees find flowers by smell. Bees have more genes for a sense of smell than other insects whose genes have been mapped. But one of the project scientists noted they have fewer genes for taste. He thinks this might help them avoid pesticides⁸ and plant diseases to find food.

The genetic research suggests that honey bees came from Africa. Their brains have similar genetic parts as the fruit fly. But fruit flies like to be alone. Scientists are interested in how, over millions of years, honey bees developed the complex social order in which they live.

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

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 pollination   

n.授粉

参考例句：

• The flowers get pollination by insects.这些花通过昆虫授粉。
• Without sufficient pollination,the growth of the corn is stunted.没有得到充足的授粉，谷物的长势就会受阻。

3 fiber   

n.纤维，纤维质

参考例句：

• The basic structural unit of yarn is the fiber.纤维是纱的基本结构单元。
• The material must be free of fiber clumps.这种材料必须无纤维块。

4 pollen   

n.[植]花粉

参考例句：

• Hummingbirds have discovered that nectar and pollen are very nutritious.蜂鸟发现花蜜和花粉是很有营养的。
• He developed an allergy to pollen.他对花粉过敏。

5 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

6 mite   

n.极小的东西；小铜币

参考例句：

• The poor mite was so ill.可怜的孩子病得这么重。
• He is a mite taller than I.他比我高一点点。

7 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

8 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》