长枝木霉对小麦禾谷孢囊线虫的致死作用  

Lethal effects of Trichoderma longibrachiatum on Heterodera avenae

作　　者：张树武[1,2,3,4] 徐秉良[1,2,3,4] 薛应钰[1,4] 古丽君[1,2] 

机构地区：[1]甘肃农业大学草业学院,兰州730070 [2]草业生态系统教育部重点实验室,兰州730070 [3]甘肃省草业工程实验室,兰州730070 [4]中-美草地畜牧业可持续发展研究中心,兰州730070

出　　处：《应用生态学报》2014年第7期2093-2098,共6页Chinese Journal of Applied Ecology

基　　金：草业生态系统教育部省部共建重点实验室项目(CY-GG-2006-013);甘肃省农牧厅生物技术专项(GNSW-2009-04);甘肃省教育厅项目(042-03)资助

摘　　要：通过室内显微观察和测定不同时期长枝木霉分生孢子悬浮液对小麦禾谷孢囊线虫2龄幼虫的致死作用,初步研究了长枝木霉分生孢子悬浮液对小麦禾谷孢囊线虫的防治潜力和作用机理.结果表明:侵染初期大量分生孢子吸附或寄生于虫体体壁,并且在分生孢子寄生的部位出现明显的缢缩.侵染后期寄生于虫体的分生孢子萌发产生大量菌丝,并形成致密的菌网将虫体缠绕或穿透虫体体壁,甚至有的虫体完全被分解.不同浓度长枝木霉分生孢子悬浮液对2龄幼虫具有明显的致死和寄生作用,且不同浓度之间存在显著差异.致死和寄生作用随着长枝木霉分生孢子悬浮液浓度的增加而增强,浓度为1.5×107cfu·mL-1的长枝木霉分生孢子悬浮液处理后72 h,2龄幼虫的死亡率和校正死亡率分别为91.3%和90.4%,14 d后对2龄幼虫的寄生率为88.7%.表明长枝木霉分生孢子悬浮液对小麦禾谷孢囊线虫的致死作用较强,该菌具有对小麦禾谷孢囊线虫的防治潜力.The lethal effect of the conidia suspension of Trichoderma longibrachiatum against second stage juveniles of Heterodera avenae was observed under microscopic conditions and studied in vitro to preliminarily determine the potential and mechanism of the conidia suspension of T. longibrachia- turn against H. avenae. Microscopic observation results showed that the conidia suspension of T. longibrachiatum adhered to or parasitized on the surface of second stage juveniles, even some para- sitized nematodes were deformed at the initial stage. Later, the second stage juveniles were wrapped and the integuments were penetrated by a large number of hyphae germinated from the conidia sus- pension of T. longibrachiatum. Even the body of dead second stage juveniles was completely lysed. In vitro studies showed that different concentrations （ 1.5 x 105 - 1.5 x 107 cfu ~ mL-1 ） of T. longi- brachiatum （conidia suspension） had strong lethal and parasitic effects on the second stage juven- iles of H. avenae, and significant differences existed among the treatments with different concentra- tions of T. longibrachiatum. In addition, the lethal and parasitic effects increased with increasing the T. longibrachiatum concentration. The mortality and corrected mortality of the second stage ju- veniles treated with the concentrations of 1.5 x 107 cfu ~ mL-1 were 91.3% and 90.4% after 72 hours, and the second stage juveniles were parasitized by 88.7% after 14 days. Therefore, the conidia suspension of T. longibrachiatum had a great lethal effect on H. avenae, and the strain could be considered as a potential bio-control agent against H. avenae.

关 键 词：长枝木霉 小麦禾谷孢囊线虫 致死和寄生作用 

分 类 号：S476[农业科学—农业昆虫与害虫防治]