黄椋种子小蜂的观察

黄椋子树是重要的木本油料之一。黄椋种子小蜂是晋东南黄椋子产区的毁灭性害虫,幼虫于种实内食害种仁,致成空壳,被害果较正常健果小呈粉红至褐色,健果墨绿色。从1959年以来由于连年受其为害,几乎无好种实可收,造成当地人民食油困难。作者对其形态、生活史及习性作了系统观察研究,绘制了形态图。并开展了大面积防治示范,收到良好的效果。以老熟幼虫于被害种实内滞育越冬,多数一年1代,部分可滞育1-2年。5月中旬至6月上旬为化蛹期,蛹期7-12天。成虫出种实后2-3天开始交配产卵;雌雄比3-4:1;卵产于幼果内,每果只产1粒卵,卵期5-7天。幼虫8月中旬至9月上旬老熟越冬。采用农业、人工和药剂相结合的综合防治措施,收到良好效果。5月底成虫始发期地面施用触杀剂,毒杀成虫效果很好。

OBSERVATIONS ON EURYTOMA PLOTNIKOVI NIKOLSKAYA

Chinese pistache is an important woody oil plant in southeastern Shanxi province.The wasp,eurytoma plot- nikovi is destructive to the plant.The infested fruits become smaller and eventually pink or brown in color. Morphological characters of this pest are described and the life history and habits are given in this paper.The larvae of the pest overwinter in the infested fruits.There is one generation each year.But some larvae are able to go hibernation for two years.Overwintering larvae are pupated in mid May to early June and the pupa stage lasts for 7 to 12 days.Copulation and oviposition take place 2-3 days after adult emergence.The sex ratio is 3-4:1. The longevity of adults lasts for about 5-7 days.Eggs are deposited into young fruits,with only one egg in each fruit.The duration of egg stage is 5-7 days.The larvae tunnel into seeds.The mature larvae appear in mid Au- gust to early September and overwinter in the infested fruits.Broadcasting contact insecticides in the early days of adult emergence by the end of May shows good control on the pest.