昆虫病原线虫扩散能力与寄主搜索能力的研究

Comparison on the Variation of Dispersal and Host-searching Ability of Five Species of Entomopathogenic Nematode

研究了5种昆虫病原线虫在无寄主（大蜡螟）存在和有寄主存在条件下的垂直与水平扩散能力及寄主搜索能力，结果表明，在沙柱中H．bacteriophora，S．glaseriNc34品系，S．feltiaeOtio品系，H．zealandica及S．carpocapsaeA24品系5种昆虫病原线虫分别可垂直扩散最远至30，30，25，20，15cm处。S．feltiae每条线虫平均垂直扩散距离最远（10．11±0．15cmn＝2740），显著地大于S．carpocapsae（5．03±0．06cmn＝2303），H．zealandica（7．13±0．10cmn＝4947），H．bacteriophora（8．31±0．22cmn＝1975）而与S．glaseri（9．86±0．29cm n＝1781）无显著差别。在沙柱中水平扩散能力研究表明，3d内S．glaseai，S．feltiae，H．zealandica，H．bacteriophora，S．carpocapsae分别可扩散最远至30，20，20，15，10cm处，H．zealandica与H．bacteriophora间、H．bacteriophora与S．carpocapsae间平均每条线虫水平扩散距离差异不显著，而其余各种间差异显著。寄主大蜡螟存在的情况下，显著提高了S．feltiae，S．glaseri，H．bacteriophora，H．zealandica的垂直扩散能力，表明该4种昆虫病原线虫可主动寻找寄主，而S．carpocapsae缺乏主动寻找寄主能力。

Vertical and horizontal dispersal ability and host-searching ability of five species entomopathogenic nematodes were studied with or without hosts (Galleria mellonella) at 30cm sandy column. The results showed that H.bacteriophora. S. glaseri (Nc34 strain). S. feltiae (Otio strain), H. zealandica and S. carpocapsae (A24 strain) could disperse vertically farthest to 30, 30, 23, 20, 15cm respectively after 3d. Vertical dispersal distance per juvenile of S.feltiae was the highest (10. 11 ± 0. 15cm n =2740), much higher than that of S. carpocapsae (5.03 ± 0.06cm n =2303),H. zealandica (7. 13 ± 0. 10cm n =4947), H. bacteriophora (8.31 ± 0.22cm n = 1975), whereas not significant difference was observed with that of S. glaseri (9.86±0.29cm n= 1781). After 3d, S. glaseri, S. feltiae. H. zealandica, H.bacteriophora, S. carpocapsae could disperse horizontally farthest to 30, 20, 20, 15, 10cm respectively. No significant difference of horizontal dispersal distance per juvenile was observed between H. zealandica and H. bacteriophora, H.bacteriophora and S. carpocapsae, and significant difference was observed among the other species. The vertical dispersal ability of four species of S. feltiae. S. glaseri. H. bacteriophora, H. zealandica was increased significantly when the host insect provided. This result showed that these four species entomopathogenic nematodes could search host positively while S. carpocapsae was lack of host-searching ability.