八字地老虎高毒力苏云金杆菌(Bacillus thuringiensis)菌株的筛选  

Virulence screening of Bacillus thuringiensis strains on Xestia c-nigrum

作　　者：于洪春[1] 王雨薇[1] 宋龙腾[1] 邓佳佳[1] 许国庆[2] 

机构地区：[1]东北农业大学农学院,哈尔滨150030 [2]辽宁省农业科学院植物保护研究所,沈阳110161

出　　处：《东北农业大学学报》2013年第10期128-133,共6页Journal of Northeast Agricultural University

基　　金：国家公益性行业(农业)科研专项(201003025)

摘　　要：摘要：苏云金杆菌是应用最广泛的昆虫病原微生物。文章采用叶片浸渍法，室内用50株Bt菌株对4～5日龄八字地老虎幼虫进行生物测定。结果表明，菌株Btl5、Bt43、Bt47、Bt65、Bt66对八字地老虎幼虫有较高毒力，其中以茵株Btl5毒力最高，其对低龄八字地老虎幼虫杀虫效果可达90％~X上，在第5、7、10天毒力回归方程分别为产28．61353x一177．58825（,-=0．944799），y=37．42650x一226．25199（r=0．983670），y=36．72547x一206．81374（r=0．931267）；其中Lcso分别为9~10’、2．4~10’、0．98~10’efu·mL～。在5×10。、1~10。efu·mL。浓度下，其LT50、u、，o和u、，0分别为2．23、2．75、3．73d；4．28、6．19、10．55d。表明该菌株是一株对八字地老虎有很好生物防治应用前景的Bt菌株。Bacillus thuringiensis （Bt） is one of the most widely-used pathogenic microorganism. By leaves dipping method, bioassay tests of fifty strains of Bacillus thuringiensis on spotted cutworm, Xestia c-nigrum of 4-5 days old showed that the strains of Bt15, Bt43, Bt47, Bt65, Bt66 had higher virulence to the larvae of spotted cutworm and among all the strains. Bt15 showed the highest virulence whose control effect to the larvae of spotted cutworm of low instar could reach up to more than 90%. The virulence regression equations of 5 d, 7 d, 10 d were y=28.61353x-177.58825（r=0.944799）, y= 37.42650x-226.25199（r=0.983670）, y=36.72547x-206.81374（r=0.931267）, respectively. Their LC,o were 9x107, 2.4x107, 0.98x10~ cfu.mL-1. Fed with Bt15 strain of 5x108 and lx10~ cfu.mL1 to 5 day-old larvae, their LTso, LTT0 and LT,o were 2.23, 2.75, 3.73 d; 4.26, 6.19, 10.55 d, respectively. It indicated that the strain Bt15 had a very good application prospect on the biological control of spotted cutworm.

关 键 词：八字地老虎 苏云金杆菌 生物测定 毒力 致死中浓度 致死时间 

分 类 号：S433.82[农业科学—农业昆虫与害虫防治]