虫口密度对蝠蛾幼虫迁移行为的影响

Effect of Population Density on the Migration Behavior of Hepialus sp. Larvae

【目的】对蝠蛾(Hepialus sp.)幼虫的迁移与虫口密度关系展开研究,一方面可确定蝠蛾在一定空间下的适宜饲养密度,另一方面可查明某些蝠蛾种类2龄虫饲养得率过低的原因,以利于制定蝠蛾的科学饲养计划,提高存活率,集约利用养殖空间。【方法】在室内其他饲养条件相同的情况下,对不同虫口密度饲养至蛹期的3种蝠蛾进行观察,统计初孵幼虫的迁移数量,测量2龄末期至蛹期幼虫在土壤中的迁移距离。【结果】不同种的蝠蛾幼虫从起始养殖环境中的迁出数量、迁移持续时间有差异,人支蝠蛾迁出数量最多、迁移时间最长,白马蝠蛾次之,云南蝠蛾再次之;蝠蛾主要在初孵幼虫阶段迁出,2龄末期后,在土壤中向四周迁移,不迁出土表,不同种的蝠蛾幼虫在土壤中迁移后形成不同的分布模式。【结论】不同种的蝠蛾幼虫迁移行为不同,在进行室内饲养时,要针对不同种的蝠蛾制定针对性的养殖计划,防止因起始养殖密度过大造成大量初孵幼虫流失;在2龄末期后的养殖过程中,要根据蝠蛾的存活数量及其分布模式科学确定养殖空间。研究成果为蝠蛾的高效扩繁提供了重要的科学依据。

[Purpose]To explore the relation between the migration and population density of Hepialus sp.larvae,on the one hand,it is possible to determine the suitable breeding density of the moth in a certain space;on the other hand,it is possible to find out the reasons for the low breeding rate of 2^nd larva of some species,witch could help to make out the scientific breeding plan of the Hepialus sp.larvae,to improve the survival rate and to increase the intensive use level of breeding space.[Methods]Three species of Hepialus sp.larvae were fed and observed till pupa stage under the same laboratory conditions except the population density,the emigration numbers of initial larva were tallied,the migration distances of the larvae developing from the end of second instar larva stage to pupa stage in soil were measured.[Results]The emigration numbers of different species were different,so did the duration days of emigration;the emigration numbers of H.renzhiensis Yang were the most and their migration period was the longest,followed by H.baimaensis Liang,and H.yunnanensis Yang,Li et Sheng came the last;the migration of Hepialus sp.larvae took place in the initial larva stage,their larvae dispersed in soil slowly and didn’t moved out from the soil after the end of second instar larva stage,they developed different distribution pattern at last.[Conclusion]Different species of Hepialus sp.had own migration behavior.The indoor breeding plan should be made in accordance with the species to prevent the loss of initial larvae caused by high initial breeding density;the breeding space should be suitable for the survival numbers and the distribution pattern of the species of Hepialus sp.from the end of second instar larva stage.The research results provided an important scientific basis for rapid propagation of Hepialus sp.