甜菜象虫药剂防治研究

甜菜象虫是甘肃河西走廊甜菜苗期的主要害虫,对甜菜危害严重。据1985—1988的调查,为害甜菜的象虫有九种之多,其中以甜菜象Bothynoderes punctiventrisGermar;甜菜毛足象phacephorus umbratus Faldermann为优势种。自1985年以来,年均为害面积为河西每年甜菜种植面积的12—15％。药剂处理种子防治甜菜象虫的试验表明;用35％甲基硫环磷乳油,种子和水以2.2—3.0:100:100的配方处理甜菜种子的防治效果最佳,杀虫率达90.0—92.0％,且残效期较长,田间保苗率达82.2—96.0％,甜菜块根产量比对照增加了10.3—55.6,产糖量比对照提高了13.0—57.5％。

A Study on Insecticide Control of the Sugar Beet Weevils

The sugar beet weevils of various species are the primary and the most harmful pests to the sugar beet at its seedling stage in the sugar beet growing districts of Hexi corridor, Gansu Province. According to the investigation from 1985 to 1988, 9 species of sugar beet weevils feeding on the sugar beet had been found, among which the most important ones were Bolhynderes puncentys Germar and Phacephorus umbratus Faldermann. About 15—20％ of the total sugarbeet growing area was damaged by sugar beet weevils each year since 1985. The results of insecticide control conducted from 1987 to 1988 showed that seed treatment with 35％ Methyl-Cyolane emulsion was the most effective measure to prevent sugar beet weevils damage. The ratio of eliminating sugar beet weevils on poison seedlings was 90.0—92.0％ and the carry-over effect lasted for a long time. The survival rate of seedlings on land was 82.2—96.0%. The root tuber yield and the sugar content of beet increased by 10,3—55,6％ and 13,0—57,5％, respectively,