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防腐剂对苏云金杆菌制剂活力毒力测定的影响 总被引:1,自引:0,他引:1
采用不同防腐剂剂处理苏云金杆菌制剂及毒力生物测定,结果表明,7#(100ml中含0.5ml10%甲醛和1ml15%尼泊金)防腐剂处理苏云金杆菌剂剂0-96h,抑制芽孢萌发和菌体活性的效果最佳,其次为2#(100ml中含1ml15%尼泊金),8#(100ml中含1ml15%尼泊金和0.05g土霉素);毒力生物测定7#防腐剂最稳定,LC50最小,灵敏度最高。 相似文献
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采用不同防腐剂处理苏云金杆菌制剂及毒力生物测定 ,结果表明 ,7# ( 1 0 0ml中含 0 5ml1 0 %甲醛和 1ml1 5%尼泊金 )防腐剂处理苏云金杆菌制剂 0~ 96h ,抑制芽孢萌发和菌体活性的效果最佳 ,其次为2 # ( 1 0 0ml中含 1ml1 5%尼泊金 ) ,8# ( 1 0 0ml中含 1ml1 5%尼泊金和 0 0 5g土霉素 ) ;毒力生物测定 7# 防腐剂最稳定 ,LC50 最小 ,灵敏度最高。 相似文献
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一株对小菜蛾高毒力的苏云金杆菌的选育及研究 总被引:2,自引:0,他引:2
利用醋酸钠 抗生素法从土壤中分离出 1株对小菜蛾 (Plutellaxylostella)高毒力的苏云金杆菌Bt 990 5。该菌对小菜蛾 4 8h的平均死亡率为 98.5 %。高于标准菌株HD 1(81.2 % )。同时 ,对该菌的形态、培养特征 ,生化特性和杀虫晶体蛋白的分子量的测定以及cry基因类型的鉴定进行了研究。 相似文献
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苏云金杆菌对甜菜夜蛾毒性的筛选 总被引:4,自引:0,他引:4
测定了 10 0株野生型苏云金芽孢杆菌菌株对夜蛾科甜菜夜蛾幼虫的毒力活性 ,经回归分析 ,2 3株对甜菜夜蛾初孵幼虫的毒力与浓度有高相关性 (R >0 .90 ) ,按LC50 计算 ,CN73活性最强 ,LC50 达 2 .393微升培养液 /克饲料 ( μL/g) ;另有 2 3株进行了不同浓度下校正死亡率的比较 ,得到高毒株 13株 ,CN33在 5μL/g浓度下校正死亡率达到 10 0 %。该结果为进一步研究奠定了基础。 相似文献
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苏云金芽孢杆菌不同亚种菌株制剂毒力效价的研究 总被引:2,自引:0,他引:2
采用苏云金芽孢杆菌制剂美国标准品:Bacillus thuringiensis subsp. Kurstaki HD-1-S-1980(H_(3a3b))对不同亚种制剂:Bacillus thuringiensis subsp. Dendrolimus U菌株(H_(4a4b))和Bacillus thuringiensis subsp. Galleriae C88菌株(H_5a5b))进行了毒力效价的研究。以U菌株制备的标样与美国标准品对不同试虫进行了比较。生物测定的结果表明,U菌株标样的效价分别为18666.6IU/mg(试虫为马尾松毛虫Dendrolimus punctatus 2龄幼虫)、22956.5IU/mg(试虫为小菜蛾Plutella xylostella 2龄幼虫),均高于美国标样16000IU/mg的水平。其敏感度为小菜蛾大于马尾松毛虫。以U菌株和C88菌株生产的中试产品用美国标准品进行毒力测定,试虫为马尾松毛虫,其结果表明,U菌株产品毒力效价为36444.4IU/mg;C88菌株产品为28521.7IU/mg,两者均明显高于美国标准品。试验结果还表明,采用美国标准品及马尾松毛虫和小菜蛾为… 相似文献
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Hua-rong Li BrendaOppert KunYanZhu RandallA.Higgins Fang-nengHuang LawrentL.Buschman 《Entomologia Sinica》2003,10(3):155-166
Commercial varieties of transgenic Bacillus thuringiensis (Bt) plants have been developed in many countries to control target pests. Initially, the expression of native Bt genes in plants was low due to mRNA instability, improper splicing, and post-translation modifications. Subsequently, modifications of the native Bt genes greatly enhanced expression levels. This is a review of the developments that made modem high-expression transgenic Bt plants possible, with an emphasis on the reasons for the low-level expression of native Bt genes in plant systems, and the techniques that have been used to improve plant expression of Bt toxin genes. 相似文献
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为防治一些重要农业害虫 ,转基因Bt作物已在许多国家商业化种植。在发展Bt作物的初期 ,未经改造的Bt基因被直接用来转化作物。但由于BtmRNA的不稳定 ,不适当的剪切以及译后变异 ,Bt在作物上的表达水平往往很低且不稳定。后来 ,科学工作者对Bt基因进行了一系列针对性的改造或人工合成 ,从而使其在植物细胞中得到高效表达。本文着重总结了这一转基因技术的发展过程。其内容包括未经改造的Bt基因在植物中表达低的原因以及改善Bt毒蛋白表达的有关技术。 相似文献
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Hua-rong Li Brenda Oppert Kun Yan Zhu Randall A. Higgins Fang-neng Huang Lawrent L. Buschman 《Insect Science》2003,10(3):155-166
Commercial varieties of transgenic Bacillus thuringiensis (Bt) plants have been developed in many countries to control target pests. Initially, the expression of native Bt genes in plants was low due to mRNA instability, improper splicing, and post‐translation modifications. Subsequently, modifications of the native Bt genes greatly enhanced expression levels. This is a review of the developments that made modern high‐expression transgenic Bt plants possible, with an emphasis on the reasons for the low‐level expression of native Bt genes in plant systems, and the techniques that have been used to improve plant expression of Bt toxin genes. 相似文献
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R. J. C. CANNON 《Biological reviews of the Cambridge Philosophical Society》1996,71(4):561-636
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Hidetaka Hori N. Selvamuthu Kumaraswami Tohru Hayakawa Toshiaki Mitsui 《Insect Science》2000,7(4):359-376
Abstract Since the first report of Bacillus sotto by Ishiwata in 1901, thousands of related papers about Bacillus thuringiensis have been documented. In the field of biocontrol of insect pests by this bacterium, after the initial discovery of several B. thuringiensis isolates specific for lepidopteran insects, the isolation of B. thuringiensis israelensis , specific to dipteran larvae by Goldberg and Margalit, and B. thuringiensis tenebrionis , specific to some group of coleopteran insects by Krieg et al . were epoch making advances. In 1992, Ohba et al . isolated B. thuringiensis ja ponensis strain Buibui, which was specific to only scarabaeid larvae. This isolate is the main target of our discussion in this review. These discoveries by which not only B. thuringiensis sciences, but also applied biological control strategies have been enriched, which inspirit us to screen novel isolates.
On the other hand, the fields of molecular biology and biochemistry studies on the structural elucidation of toxin proteins and mechanism of action have also tremendously progressed. But the complete mechanism has yet to be solved. For instance, interaction between receptor proteins locating on the plasma membrane of insect midgut epithelial cells and insecticidal proteins has not been fully sketched- In a way, this field is still in chaos. Addressing these exciting and enigmatic subjects will eventually lead to the construction of sustainable agriculture in the 21st century. 相似文献
On the other hand, the fields of molecular biology and biochemistry studies on the structural elucidation of toxin proteins and mechanism of action have also tremendously progressed. But the complete mechanism has yet to be solved. For instance, interaction between receptor proteins locating on the plasma membrane of insect midgut epithelial cells and insecticidal proteins has not been fully sketched- In a way, this field is still in chaos. Addressing these exciting and enigmatic subjects will eventually lead to the construction of sustainable agriculture in the 21st century. 相似文献
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苏云金芽胞杆菌肠毒素基因的PCR检测 总被引:7,自引:0,他引:7
采用多重引物PCR进行了 45株苏云金芽胞杆菌、2株蜡状芽胞杆菌和 2株球形芽胞杆菌溶血素BL ,肠毒素T和entS基因的检测 ,结果表明 95 6%苏云金芽胞杆菌含溶血素hblA基因 ,91 1 %含bceT基因 ,93 3%含entS基因。用两种商业化肠毒素检测试剂盒TECRA和RPLA进行所有菌株肠毒素的体外免疫测定 ,大部分苏云金芽胞杆菌和阳性蜡状芽胞杆菌都能产生不同水平的肠毒素活性 ,同hblA基因PCR检测结果基本相符。尽管DBT0 0 7和T2 4 0 0 1含有hblA基因 ,但用TECRA却检测不到肠毒素 ;Dmu39菌株不含肠毒素基因 ,但用TECRA却检测出高的肠毒素活性。苏云金芽胞杆菌BDT2 4 8和球性芽孢杆菌不含肠毒素基因和肠毒素。结果表明昆虫病原菌苏云金芽胞杆菌的安全性有待进一步研究 相似文献
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电脉冲法转化苏云金芽孢杆菌BMB171的研究 总被引:3,自引:0,他引:3
研究了用电脉冲法转化苏云金芽孢杆菌受体菌BMB171的优化条件以及由转化导入的几类cry基因在BMB171中的表达效果。结果表明,采用SG溶液作电脉冲缓冲液,用10.okV/cm的脉冲场强和1次电脉冲(4.6ms)以及采用对数前期(OD650nm为0.2~0.3)收获的受体菌,可以达到最高转化频率,其中用pHT3101电转化 BMB171的最高频率达 8×107转化子/μg DNA。转化频率随质粒pHT3101浓度的增加,在54.69pg/mL至3.50μg/mL范围内 相似文献
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自从 190 1年Ishiwata首次报导猝倒菌以来 ,已有数千篇有关苏云金芽孢杆菌的论文相继发表。在苏云金芽孢杆菌 (Bt)的害虫生物防治领域中首次发现对鳞翅目昆虫有杀虫专一性的Bt菌株以后 ,又有了划时代的进展。Goldberg和Margalit发现了杀双翅目幼虫的以色列亚种 (subsp .isrealensis) ,以及Kreig等人发现了对某些鞘翅目幼虫有毒的拟步行甲亚种 (sbusp .tenebrionis)。 1992年 ,Ohba等分离到了日本亚种(subsp .japonensis)对金龟子有专一性杀虫作用的菌株Buibui。该菌株及与之有关的研究进展即是本文讨论的重点。这些发现不仅丰富了苏云金芽孢杆菌科学 ,也丰富了生物防治的应用策略。另一方面 ,在毒素蛋白结构及其杀虫机制的分子生物学和生物化学领域也已获巨大进展。但对杀虫机制尚未完全明了。例如 ,对杀虫蛋白与中肠上皮细胞原生质膜上的受体蛋白的相互作用就知之甚少。这一领域在某种程度上还是众说纷纭。展论这些令人兴奋而又难解的课题将最终促成二十一世纪可持续农业的建立。 相似文献