塔六点蓟马对山楂叶螨的控制效果

Experiments of releasing Scolothrips takahashi to control Tetranychus viennensis in cages

【目的】探索塔六点蓟马的田间高效释放技术。【方法】在罩笼苹果树上先后定量接入山楂叶螨和塔六点蓟马,定期调查2者的数量消长变化。【结果】在山楂叶螨越冬代出蛰期或第一代雌成螨高峰期接螨密度为2~14头·m-2时,14 d后接种式释放塔六点蓟马雌成虫0.5头·m-2,可以将山楂叶螨高峰期的密度控制在经济危害允许水平之下,此时叶螨增长的抑制率高达90%。【结论】田间释放的适宜时机为:当调查树冠内膛主干附近平均10个叶丛枝有山楂叶螨雌成螨4~28头时,根据螨多早放的原则于7~14 d后按每m20.5头的量在树冠内膛释放塔六点蓟马。

【Objective】To test the efficiency of releasing Scolothrips takahashi to control Tetranychus viennensis.【Method】Experiments were carried out in cage to observe the fluctuation of Scolothrips takahashi and Tetranychus viennensis.In early season,some female adults of Tetranychus viennensis were reset on yong apple tree,some days later some female adults of Scolothrips takahashi were released,andthen their amount change was investigated every 7-10 days.【Result】The results showed that when Tet-ranychus viennensis female mite number was 2-14 per m2 on 1 April or 5 May,14 days later,releasing Scolothrips takahashi female adult at 0.5 heads per m2 could keep Tetranychus viennensis female mite number below the economic injury level all season,and the percentage of Tetranychus viennensis increase inhibition reached up to 90%.【Conclusion】It is suggested the suitable timing for releasing Scolothrips takahashi in orchard is 7-14 days later when Tetranychus viennensis female adult mite number is about 4 to 28 heads per 10 leaf-crowd branches near the trunk,and the more mites and the earlier releasing timing is also recommended.