高中英语 晨读英语美文60篇 56 Genetically Modified Foods—Feed the World素材

Genetically Modified Foods—Feed the World?

If you want to spark a heated debate at a dinner party,

bring up the topic of genetically modified foods.

For many people, the concept of genetically altered,

high-tech crop production raises all kinds of environmental,

health, safety and ethical questions.

Particularly in countries with long agrarian traditions—

and vocal green lobbies—

the idea seems against nature.

In fact, genetically modified foods are already very much a part of our lives.

A third of the corn and more than half the soybeans

and cotton grown in the US last year were the product of biotechnology, according to the Department of Agriculture.

More than 65 million acres of genetically modified crops

will be planted in the US this year.

The genetic is out of the bottle.

The issue is simple and urgent:

Do the benefits of biotech outweigh the risks?

The statistics on population growth and hunger are disturbing.

Last year the world’s population reached 6 billion.

And by 2050, the UN estimates,

it will probably near 9 billion.

[01:16.30]almost all that growth occer in developing countries.

[01:20.00]At the same time,

[01:20.82]the world’s available cultivable land per person is declining. [01:25.40]The UN estimates that nearly 800 million people

[01:29.45]around the world are undernourished.

[01:31.53]The effects are devastating.

[01:33.40]How can biotech help?

[01:35.57]Biotechnologists have developed genetically modified rice

[01:39.73]that is fortified with beta-carotene --

[01:42.04]which the body converts into vitamin A—

[01:44.54]and additional iron,

[01:46.30]and they are working on other kinds of nutritionally improved crops. [01:50.78]Biotech can also improve farming productivity in places

[01:54.71]where food shortages are caused by crop damage attribution to pests, [01:59.65]drought, poor soil and crop viruses, bacteria or fungi.

[02:04.47]Damage caused by pests is incredible.

[02:07.19]The European corn borer, for example,

[02:09.71]destroys 40 million tons of the world’s corn crop annually,

[02:14.20]about 7% of the total.

[02:16.37]Incorporating pest-resistant genes into seeds can help restore the balance.

[02:21.51]In trials of pest-resistant cotton in Africa,

[02:24.59]yields have increased significantly.

[02:27.20]So far, fears that genetically modified,

[02:30.50]pest-resistant crops might kill good insects as well as bad appear unfounded.

[02:36.50]Viruses often cause massive failure in staple crops in developing countries.

[02:41.97]Two years ago, Africa lost more than half its cassava crop—

[02:46.01]a key source of calories—

[02:47.88]to the mosaic virus.

[02:49.52]Genetically modified,

[02:51.06]virus-resistant crops can reduce that damage,

[02:53.78]as can drought-tolerant seeds in regions

[02:57.17]where water shortages limit the amount of land under cultivation.

[03:00.69]Biotech can also help solve the problem of soil that contains excess aluminum,

[03:06.24]which can damage roots and cause many staple-crop failures.

[03:10.09]A gene that helps neutralize aluminum toxicity in rice has been identified.