对甜菜夜蛾具有高毒力的Bt菌株筛选  

Screening of Bacillus thuringiensis strains with a strong virulence against Spodoptera exigua larvae

作　　者：郭靖[1,2] 周子珊[2] 蔡吉林[2] 惠识瑶[1,2] 张杰[2] 高继国[1] 束长龙[2] 

机构地区：[1]东北农业大学生命科学学院,哈尔滨150030 [2]中国农业科学院植物保护研究所植物病虫害生物学国家重点实验室,北京100193

出　　处：《植物保护》2013年第1期8-13,共6页Plant Protection

基　　金：国家"863"计划项目(2011AA10A203);国家"973"计划项目(2009CB118902)

摘　　要：依据对夜蛾科具有高毒力cry基因的序列,设计特异性引物对实验室保存的对鳞翅目害虫高效的菌株资源进行筛选。通过比较质粒图谱,对其多样性进行了研究。进一步测定Bt菌株对甜菜夜蛾的杀虫活性,筛选出高毒力的菌株。从192株菌株中筛选出15株对夜蛾科害虫具有高活性的菌株,包含的基因类型有:cry1A、cry1C、cry2A、cry9和vip3A类基因,晶体形态包含:双锥体形、方形、球形;其中2株菌表达130ku和60ku的蛋白,1株菌表达130ku和70ku的蛋白,其余菌株均表达约130ku的蛋白;这15株菌通过质粒图谱分析分为8种类型;3株菌对甜菜夜蛾幼虫具有高毒力,其中菌株PS3-C2对甜菜夜蛾LC50为1.87μg/mL。本研究成功筛选出对甜菜夜蛾具有高毒力的菌株3株,其中PS3-C2菌株与对照菌株KN11活性相当,为新型杀虫基因分离克隆与制剂的研发奠定了基础。According to the sequence of the known cry genes with a strong insecticidal activity against Spodoptera exigua, specific primers were designed for Bt strain selection. After PCR screening, the diversity of selected strains were investigated by comparison with plasmid profiles. Furthermore, strains with high toxicity to S. exigua were screened by bioassay. Fifteen strains with high activity against S. exigua were obtained from 192 isolates. These strains contained cry1A, cry1C, cry2A, cry9 and vip3A genes, forming bipyramidal, square or globular crystals. They were classified into eight types according to plasmid profile. One of them expressed both 130 ku and 70 ku proteins, two expressed 130 ku and 60 ku proteins, and three expressed only 130 ku protein. The strain PS3- C2 had the highest activity, with a LC50of 1.87 μg/mL. Three high-toxicity Bt strains against S. exigua were obtained, and the strain PS3-C2 was a native strain with a comparable activity with the control strain KNll. In conclusion, the present study laid a foundation for Bt pesticides development.

关 键 词：苏云金芽胞杆菌 CRY基因 BT制剂 杀虫活性 

分 类 号：S476.11[农业科学—农业昆虫与害虫防治]