This is the VOA SpecialEnglish AGRICULTURE REPORT.
Farmers in the American state of California are guarding againstan insect called the glassy-winged sharpshooter. It carries Pierce’sdisease, a bacterial disease that attacks grape plants and othercrops. Government and industry are working to fight the sharpshooterand the deadly disease.
California is a leading producer of wine, the alcoholic drinkmade from grapes. The California wine industry providesthirty-three-thousand-million dollars for the state’s economy.
For more than a century,California grape growers have battled Pierce’s disease. It hascaused major damage to Los Angeles area farmers several times.
A new, more threatening glassy-winged sharpshooter arrived insouthern California twelve years ago. Scientists believe this insectcame from the southern United States. Officials estimate it hascaused fourteen-million dollars in damage over the past severalyears. Experts say it is now ready to attack other parts ofCalifornia.
The glassy-winged sharpshooter feeds on hundreds of differentkinds of plants. The small insect spreads Pierce’s disease as itmoves from plant to plant. The bacterial disease slowly kills theplants. There is no known treatment. In addition, the insect carriesdiseases that can harm peaches, oranges and other crops.
American scientists are studying ways to stop the sharpshooter.One method involves covering grapevines with particles of kaolin, afine white clay. The particles stick to the insects when they landon treated grapevines. The insects do not eat the plants, and areunlikely to leave their eggs there. A similar treatment hassuccessfully protected other kinds of fruit from insects.
Other scientists are studying ways to safely kill sharpshooters.They found that some chemicals were very effective. Some of thechemicals were still killing sharpshooters four weeks after theplants were treated.
However, scientists want to guarantee that the chemicals do notkill helpful insects, such as egg parasitoids. They are a leadingnatural enemy of sharpshooters. Scientists have already released onekind of egg parasitoid in California. Other scientists are studyingparasitoids that eat the eggs of a native South Americansharpshooter.
This VOA Special English AGRICULTURE REPORT was written by GeorgeGrow.