三株球孢白僵菌的分离鉴定与其对粘虫的室内毒力  

Isolation and Identification of Three Beauveria bassiana Isolates and Their Virulence against Mythimna separata under Laboratory Condition

作　　者：程茵 郑吉阳 王敦[1] CHENG Yin;ZHENG Jiyang;WANG Dun(Institute of Entomology,Northwest A&F University,Yangling 712100,China)

机构地区：[1]西北农林科技大学昆虫学研究所,杨凌712100

出　　处：《中国生物防治学报》2022年第2期521-530,共10页Chinese Journal of Biological Control

基　　金：陕西省科技重大专项(2020zdzx03-03-02);国家重点研发计划(2018YFD0600202-03)。

摘　　要：通过黄粉虫虫饵法从河北省采集的土样中分离得到三株昆虫病原真菌,结合形态学特征和rDNA序列分析对菌株进行了鉴定,结果表明:三株均为球孢白僵菌Beauveria bassiana,编号依次为Z-G2-5、M-G4、M-G3。通过生测发现3株球孢白僵菌菌株均能有效感染粘虫幼虫,三株球孢白僵菌对粘虫3龄幼虫的毒力不同:在5×10^(8)孢子/mL剂量下,菌株Z-G2-5第6 d时对粘虫的累计校正死亡率达到96.77%,LT_(50)为3.02 d,LC_(50)为4.95×10^(6)个孢子/mL。而菌株M-G3、M-G4的累计死亡率分别为66.67%、71.11%;LT_(50)分别为4.89 d、3.97 d;LC_(50)分别为1.18×10^(8)个孢子/mL、1.13×10^(7)个孢子/mL。上述结果表明,相比其他两株菌,菌株Z-G2-5对粘虫的致病力更强,致死速度更快,具有较大的应用价值,可作为粘虫幼虫生物防治的候选菌株。Three entomopathogenic fungi strains were isolated from soil samples collected from Hebei Province using Tenebrio molitor larvae as bait and were identified through morphological characteristics and rDNA sequence analysis.Results showed that the three strains were Beauveria bassiana,named Z-G2-5,M-G4 and M-G3,respectively.Bioassay showed that all the three B.bassiana strains could infect the larvae of Mythimna separata effectively,but showed varying virulence to the 3^(rd) instar larvae of M.separata.At 5×10^(8) spores/mL,the strain Z-G2-5 caused a peak cumulative corrected mortality of 96.77%at the 6_(th) day post infection,with a LT_(50) of 3.02 d,a LC_(50) of 4.95×10^(6) spores/mL.At the same concentration,the cumulative mortality with M-G3 and M-G4 strains were only 66.67%and 71.11%,respectively,the LT_(50) values were 4.89 d and 3.97 d,respectively,and the LC_(50) values were 1.18×10^(8) spores/mL and 1.13×10^(7) spores/mL,respectively.The results indicated that,compared with the other two strains,the strain Z-G2-5 had stronger pathogenicity and faster lethal rate to armyworm larvae,and it can be used as a candidate strain with potential application for biological control of M.separata.

关 键 词：球孢白僵菌 粘虫 致病力 生物防治 鉴定 

分 类 号：S476.1[农业科学—农业昆虫与害虫防治]