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British scientists have discovered the willow trees (柳树) planted at an angle could increase sugars for biofuel production.
Willow is a fast-growing species. It is already used to produce fuels for the renewable heating and power market. In future it could also help to produce biofuel to power vehicles. It has been known that when willows growing in the wild are blown sideways they tend to produce more sugars. But for a while it has not been known why this happens.
Researchers at Imperial College London, led by Dr Nicholas Brereton and Dr Michael Ray of the Department of Life Sciences, have now solved the mystery. When the tree is blown sideways, its genes produce large numbers of sugar molecules (分子) to straighten the tree upwards.
“This is an important breakthrough. Our study now shows that natural genetic changes are related to these differences. And this could well be the key to unlocking the future for green energy from willow,” said Dr Brereton.
The research was carried out under lab conditions. The willows were grown at an angle of 45 degrees. They were compared to willows which grow naturally straight upwards. The team then looked for the same effect among the willows growing on the Isle of Orkney where strong winds cause the trees to bend at extreme angles. They discovered that the Orkney trees produce five times the amount of sugars found in willows grown in sheltered conditions.
Willow is widely planted across the UK. The results show that biofuel crops such as willows could be grown in climatically challenging conditions where chances of growing food crops are limited.
The study is published in Biotechnology for Biofuels.
 
8. What may happen when willows are planted in strong winds?
  A. They stop growing.                     
B. Few sugars are produced.
  C. They try to grow sideways.               
D. Changes in genes take place.
9. The Orkney willows ______________.
  A. are unusually rich in sugars              
B. grow naturally straight upwards
  C. looked taller than ordinary willows         
D. are stronger than those growing in labsZxxkCom
10. Farmers living in challenging climate ____________.
  A. use biofuel for heating and power         
B. are encouraged to grow biofuel crops
  C. can planted different kinds of food crops      
D. should make their willows grow straight
11. Where does this passage probably come from?
A. A personal diary.     B. A newspaper ad.    
C. A scientific journal   D. A travel magazine
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