中华甲虫蒲螨寄生双条杉天牛幼虫血淋巴变化

为了解中华甲虫蒲螨Pyemotes zhonghuajia Yu and Zhang对双条杉天牛Semanotus bifasciatus(Motschulsky)的致死过程,将已发育成熟的中华甲虫蒲螨膨腹体移入放有双条杉天牛2龄幼虫的玻璃指形管中,在蒲螨的一个生活史60h内,观察其取食行为,并在移入后每隔12h用考马斯亮蓝法分别测定天牛幼虫和蒲螨血淋巴中总蛋白质含量。结果显示,蒲螨蛋白含量总体呈现上升的趋势,在36～48h上升幅度最大,达61.78%;而天牛幼虫血淋巴总蛋白质含量则呈总体下降趋势,与对照相比,在36～48h之间下降最为明显;蒲螨总蛋白质含量在24h后处理组与对照组差异均为极显著,天牛幼虫总蛋白质含量在48h后处理组与对照组差异显著,这表明蒲螨在24h已搜寻到寄主开始取食,且取食效果明显,而天牛幼虫在48h后表现为麻痹致死,36～48h蒲螨取食对天牛致死起关键作用。12h时处理组的双条杉天牛幼虫总蛋白质含量比对照组略高,推测是由于幼虫对外寄生物蒲螨具有一定的免疫防御反应。

Changes on the total protein content in hemolymph of Semanotus bifasciatus after infected by Pyemotes zhonghuajia

Changes in the total protein content in hemolymph of the mite Pyemotes zhonghuajia Yu and Zhang（Acari：Pyemotidae） and the beetle Semanotus bifasciatus（Motschulsky）（Coleoptera：Cerambycidae） after parasitization by P.zhonghuajia were assayed.Third-instar larvae of S.bifasciatus and mature P.zhonghuajia were placed in the cuvettes and the foraging behavior of P.zhonghuajia observed carefully over one generation.The total protein content of the haemolymph of the beetle larvae and mites was measured every 12 hours using the Brodford method.The results show that total protein in mite hemolymph increased while that of the beetle larvae declined.The maximum total haemolymph protein in P.zhonghuajia was 61.78%,which was recorded after 36 h and 48 h.A significant difference in the haemolymph protein of the mites was apparent after 24 hours.The haemolymph content of S.bifasciatus changed significantly compared to the control after 36 h to 48 h,the period in which feeding by mites caused the beetle larvae to became paralytic.This suggests that the effect of parasitiztion by P.zhonghuajia on S.bifasciatus was most extreme 36 to 48 h after exposure.After 12 h the haemolymph protein of the beetle larvae was slightly higher than that of the control,which suggests that they may have an initial immune reaction against attack by mites.