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AGRICULTURE REPORT - Scientists Find Compound in Smoke that

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AGRICULTURE REPORT - Scientists Find Compound1 in Smoke that Helps Seeds Grow
By Mario Ritter

Broadcast: Tuesday, July 20, 2004

This is Steve Ember with the VOA Special English Agriculture Report.

A discovery about a chemical in smoke could be a big help to farmers. Smoke causes lots of seeds to begin to grow. But smoke contains lots of different substances. No one knew which one caused the process of germination2 to begin.

Now researchers from the University of Western Australia say they know. They published their findings3 this month in the magazine Science. The compound is called butenolide.

To find it, the Australian team burned plants as well as paper. Both contain cellulose, the basic material of all plant life. The team separated butenolide from the other substances in the smoke from the burnt cellulose. Their work took eleven years.

They performed experiments on seeds that normally4 germinate5 after fires. They also included seeds from plants that do not normally need fire to germinate. They found that both kinds of seeds germinated6 at a high rate when treated with butenolide. They found that even an extremely small amount of this carbon-based chemical can be effective.

The discovery of butenolide could mean a lot not just to farmers but also to scientists who want to help rare plants grow. It could be used on wild lands and to help forests grow back more quickly after fires.

Farmers could treat seeds with butenolide to increase the productivity7 of their crops. Kingsley Dixon, a member of the Australian team, notes that it could also be used to control unwanted plants. A farmer could treat fields with the chemical. This would cause weeds to germinate and grow. Then the farmer would use other treatments to kill the weeds before any crops are planted.

Most kinds of seeds require a period of inactivity before they can germinate and send out roots. Inactivity is a natural defense8, so the plants do not attempt to grow when conditions are poor. Some seeds need cold weather before they can germinate. Others cannot sprout9 until their outer skin is broken, which heat from a fire can do.

Smoke from forest fires is known to cause seeds to germinate immediately. Now, scientists know what it is in smoke that causes seeds to start to grow. What they do not know yet is why butenolide does what it does.

If you have a question about agriculture, we might be able to answer it on the air. Send an e-mail to [email protected]. And put the word agriculture in the subject line.

This VOA Special English Agriculture Report was written by Mario Ritter. This is Steve Ember.


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点击收听单词发音收听单词发音  

1 compound MXEzZ     
n.化合物;大院;adj.化合的;vt.加重;使化合
参考例句:
  • Air is a mixture,not a compound of gases.空气是气体的混合物,不是化合物。
  • How many households in the compound?院内有几家住户?
2 germination e3b6166de2e0bafce0467a9f740b91e3     
n.萌芽,发生;萌发;生芽;催芽
参考例句:
  • At the onset of germination, the hypocotyl elongates rapidly by cell enlargement. 萌发开始时,下胚轴依靠细胞增大而迅速伸长。 来自辞典例句
  • Excessive moisture is unfavourable for soybean germination. 水分过多对于大豆萌发是不利的。 来自辞典例句
3 findings 4tYzV9     
n.发现物( finding的名词复数 );调查(或研究)的结果;(陪审团的)裁决
参考例句:
  • It behoves us to study these findings carefully. 我们理应认真研究这些发现。
  • Their findings have been widely disseminated . 他们的研究成果已经广为传播。
4 normally ln8zVb     
adv.正常地,通常地
参考例句:
  • I normally do all my shopping on Saturdays.我通常在星期六买东西。
  • My pulse beats normally.我脉搏正常。
5 germinate hgSx1     
v.发芽;发生;发展
参考例句:
  • Seeds will not germinate without water.没有水,种子是不会发芽的。
  • Can thin and hollow seeds germinate?瘦瘪的种子能够发芽吗?
6 germinated 34800fedce882b7815e35b85cf63273d     
v.(使)发芽( germinate的过去式和过去分词 )
参考例句:
  • First, the researchers germinated the seeds. 研究人员首先让种子发芽。 来自辞典例句
  • In spring they are germinated and grown for a year in beds. 春季里,他们在苗床发芽并生长一年。 来自辞典例句
7 productivity IQoxT     
n.生产力,生产率,多产
参考例句:
  • Farmers are introducing in novations which increase the productivity.农民们正引进提高生产力的新方法。
  • The workers try to put up productivity.工人设法提高生产率。
8 defense AxbxB     
n.防御,保卫;[pl.]防务工事;辩护,答辩
参考例句:
  • The accused has the right to defense.被告人有权获得辩护。
  • The war has impacted the area with military and defense workers.战争使那个地区挤满了军队和防御工程人员。
9 sprout ITizY     
n.芽,萌芽;vt.使发芽,摘去芽;vi.长芽,抽条
参考例句:
  • When do deer first sprout horns?鹿在多大的时候开始长出角?
  • It takes about a week for the seeds to sprout.这些种子大约要一周后才会发芽。

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