松毛虫脊茧蜂生物学特性的研究

松毛虫脊茧蜂是马尾松毛虫幼虫常见的寄生性天敌,国内分布广泛。在苏皖地区对松毛虫幼虫的平均寄生率为1.8～20.1％。该蜂在苏皖地区一年发生2代,以幼虫在越冬代3～4龄松毛虫幼虫体内越冬。翌年2～3月寄主幼虫虫体缩小,两端微尖,中间隆起呈纺锤形,固定在树皮下或小枝、针叶等部位。越冬代及第1代成虫发生期长,幼虫有滞育现象,因此生活史不整齐,有世代重叠现象。蛹期19～24天。成虫在白天羽化、交尾、产卵,平均寿命7.7～24.7天,补充营养可延长寿命。成虫有较强趋光性,脊茧蜂的诱虫量与松毛虫发生数量密切相关。茧蛹期有5种重寄生天敌,全年平均重寄生率18.6％,其中以窄柄姬蜂最为重要。

A RESEARCH ON THE BIOLOGY OF ALEIODES DENDROLIMI (MATSUMURA)

Alelodes dendrolimi is widely distributed in China. According to the study carried out in Jiangsu and Anhui province during 1982~1984. The average percentage of parasitisms of larvae of Dendrolimus punctatus was 1.8~20.1%. It has 2 generations each year. Winter is passed as larvae within the larvae of 3~4 instar of D. punctatus in over wintering generation. The body of host larvae shortens, and the both ends are slightly narrow, and the middle humps up and looks like a spindle in next spring. It is posited under the bark or on the sprigs and needles pupation period varies from 19 to 24 d. The adults copulates and oviposits on the day time. The longevity of adults varies from 7.7 to 24.7d. The sex ratio reached 1:l.l in 1983, and it was 1:2.5 in 1984. The average percentage of hyperparasitisms was 11.1%. The highest percentage of hyperparasitism was 32% (in first generation). Brachypimpla(?) latopetiolator was observed to be more important than others.