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科学家寻味丢失的玫瑰花香

2010-10-17来源:和谐英语

Professor Givik Clark refers to this tiny rose as his proof of concept. In just a couple of weeks, he will know if 3 long years of research have paid off. The flower has been genetically egineered to give it back something it lost for generations of breeding.

Back in the old days, roses all have fragrance, but since 1950s, about 80% or 90% of flowers that are on the market like roses don't have any fragrances.

3 years ago, Clark decided to put the perfume back into the rose. The fragrance in all flowers including roses comes from the volatile chemicals they produce. Each of which has a genetical marker. But Clark had a problem. The rose is one of the most genetically complex flowers in the world. And its genome has not yet been mapped, so it couldn't begin to look for the gene that produces fragrance. Then, came his heroic moment.

The far less complicated petunia has been genetically mapped, and it contains a gene that produces rose oil, along with other genes such as wintergreen and clove oil. In combination, they produced the fragrance of petunia. But for Clark, only the rose oil gene matter. Clark and his team isolated the rose oil gene and cloned it. Then they used agro-bacterium, a bacterium that can transfer DNA between plants to add the cloned gene to genetically structure of a rose.

The idea is that if we can do it, and jump species barriers, then we should be able to do it to any plants that we want to make fragrance. And now we can start talking about making design for flowers. Things that smell like mints, things that smell like, maybe more like root beer, things that are sticky,sweet. And so, we just have to now go to clone those genes out of different plants for doing what we want to do.

They say volatile chemicals that produce fragrance, produce taste as well. Clark says that if we can enhance the smell of roses, we should be able to enhance or change the taste of any food or vegetable.

We look at it and say the opportunity is limitless, you can talk about a better taste in strawberry, you can talk about a better taste in tomato. And if you make a better tasting for some vegetables, then people simply are gonna eat more of them.

For now, Clarks says after all the effort, he will be delighted if his genetically egineered flower turns out his plan. He says only then would he be able to sit back,relax and smell the roses.

Ben Gruber, Reuters.