Luyện nghe tiếng anh

This is the VOA Special English Agriculture Report. California is trying to control an invasion of the light brown apple moth. The insect is native to Australia and is now found widely in New Zealand, Britain, Ireland and New Caledonia. Hawaii had them in the late eighteen hundreds, but this is the first discovery on the mainland United States.
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Luyện nghe tiếng anh Bai nghe 3. This is the VOA Special English Agriculture Report. California is trying to control an invasion of the light brown apple moth. The insect is native to Australia and is now found widely in New Zealand, Britain, Ireland and New Caledonia. Hawaii had them in the late eighteen hundreds, but this is the first discovery on the mainland United States. Officials say it could cause more than one hundred thirty million dollars in crop damage and control costs if the moth spreads to agricultural production areas. California is the nation's leading agricultural state. The industry is valued at thirty-two billion dollars. The light brown apple moth can attack more than two hundred fifty kinds of plants and trees. It causes damage by feeding on leaves, new growth and fruit, including grapes -- bad news for California's wine industry. More than thirty thousand traps have been deployed as part of the effort to fight the invasion. As of last week the traps had caught almost five thousand light brown apple moths. The insects have been found in several counties but mostly in Santa Cruz and Monterey along the Central Coast. The others have mostly been found in the San Francisco Bay Area, to the north. The first discovery came in February. A private citizen captured two suspicious moths in a blacklight trap on his property near Berkeley. A laboratory confirmed their identity in March. Then, in May, the United States Department of Agriculture ordered action to prevent the spread of the insect. It restricted the movement of products including nursery plants, cut flowers and greenery from several counties in California and all of Hawaii. Shipments must be inspected and declared insect-free before they can be transported to other states. The California Department of Food and Agriculture says growers have the choice to destroy affected plants or treat them with a chemical, chlorpyrifos. Another substance, Bt, is a natural organism used as a biological control. In June, weekly ground treatments with Bt began on more than two hundred properties in two counties, Contra Costa and Napa. Napa is famous for its wine grapes. Control plans are being developed for the wider area, based in part on the advice of experts from Australia and New Zealand. Mexico has suspended imports of some products from the affected areas. It also is requiring more inspection of products from outside the affected counties. Bai nghe 2. And that's the VOA Special English Agriculture Report, written by Jerilyn Watson. I'm Faith Lapidus. This is the VOA Special English Agriculture Report. Someday, rice plants might not only provide food but also a way to prevent cholera and other diseases. Cholera is a bacterial infection of the intestines. Today it is found mostly in Africa, Asia and Latin America. Current vaccines to protect against cholera must be kept in cold storage. The need for refrigeration limits use in poor countries. But research in Japan may lead to rice plants that contain a cholera vaccine that does not need to be kept cold. So far, the research has been carried out only on mice. The Proceedings of the National Academy of Sciences in the United States published the study earlier this month. Hiroshi Kiyono of the University of Tokyo and his team experimented with genetic material from the bacterium responsible for cholera. They placed it into the Kitaake rice plant. Mice ate the genetically changed rice seeds as a powder. The report says the vaccine was not destroyed by stomach acid; instead, the animals developed antibodies against the cholera toxin. The scientists say the vaccine remained active even after being stored at room temperature for more than a year and a half. People would take the vaccine as a drug that contains the powder. Cholera is usually spread through water or food, in places where conditions are dirty and drinking water supplies are unsafe. Cholera infections are often mild. But some people develop severe cases. The World Health Organization says half of them will die if they are not treated. The researchers say the experimental cholera vaccine produced reactions in the immune system and in areas of mucosal tissue. Mucosal surfaces include the mouth, nose and reproductive organs. Cholera as well as viruses like those that cause influenza and AIDS infect these areas. The scientists have great hopes for rice-based vaccines as a way to protect large populations against mucosal infections. There would be no need for injection, since the vaccine would be taken by mouth. Yet scientists have tried for some time to make plant-based vaccines. Researchers in the United States have developed one for Newcastle disease in chickens, but so far there are no products for humans. At the same time, scientists have to deal with concerns about genetically engineered plants accidentally mixing with food crops. And that's the VOA Special English Agriculture Report ...