VOA慢速英語: 科學(xué)家發(fā)現(xiàn)咖啡的秘密

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An international team of researchers has created a sequence, or map, of the genes of the coffee plant known as Robusta. About one-third of the coffee drunk worldwide comes from this plant.

The researchers call coffee “the irresistible bean that delivers the most widely consumed psychoactive drug in the world.”

Researchers hope to use the map they created to make changes to the plant’s genes.

The researchers were surprised to discover the genes for caffeine. They discovered coffee’s caffeine genes are not linked to the caffeine genes in the cacao tree. Cacao beans are used to make chocolate.

With the new gene map, researchers say they may be able to develop plants that can survive climate change. They may also be able to create a coffee plant that does not have caffeine. The researchers say that would let growers and coffee makers produce coffee that tastes better than the kind that has the caffeine removed.

We drink 2.5 billion cups of coffee every day. Coffee is the main agricultural crop in many tropical countries.

The genetic map of the coffee plant Robusta was published in the journal Science. The researchers say the plant “joins a long list of crop species that have been sequenced using ever-improving” computer programs.

I’m Christopher Cruise.

VOA health correspondent Jessica Berman reported this story from Washington. Christopher Cruise wrote it for Learning English. Jeri Watson edited it.

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Words in This Story

psychoactive – adj. having an effect on the brain; used to describe the effects of a drug

plant - v. to put into the ground to grow; n. a living growth from the ground which gets its food from air, water and earth

map - n. a picture of the earth’s surface or a part of it

discover - v. to find or learn something

produce - v. to make; to create; to cause something to be; to manufacture

crop(s) - n. plants that are grown and gathered for food, such as grains, fruits and vegetables