转Bt棉不同生长期及不同器官杀虫蛋白表达量的免疫？…

转苏云金杆菌（Ｂａｃｉｌｌｕｓ ｔｈｕｒｉｎｇｅｎｓｉｓ）杀虫蛋白基因棉花（下称Ｂｔ棉）在不同生长期及不同器官上对锦铃虫杀虫活性存在明显差异。目前国内普遍使用生物测试法检测Ｂｔ棉对棉铃虫的杀虫活性。但无法定量检测Ｂｔ棉中杀虫蛋白的表达量。本实验室建立的酶联免疫学测定方法（ＥＬＩＳＡ）,可定量检测棉器官内杀虫蛋白的含量。它具有检测周期短,操作简单的优点。用ＥＬＩＳＡ方法检测Ｂｔ棉杀虫蛋白的含量,结果     

Bt防治栗实象甲的试验

Bt(Bacillus thuryingieusis)已成为大规模生产和运用的生物杀虫制剂，通过试验，发现湖北康欣实业有限公司生产的生绿Bt悬浮剂在给定施用范围内稀释800倍杀灭栗实象甲效果最好。     

转基因抗虫棉害虫发生规律与防治技术研究

转Bt基因棉是运用生物工程技术把Bt菌的合成毒蛋白基因转育到棉花上,使棉株的细胞产生杀虫毒素,对棉铃虫等鳞翅目的幼虫具有毒杀作用。转基因抗虫棉大面积种植后,棉田害虫的格局发生了重大变化,为掌握其发生规律和防治技术,及时有效地控制转基因抗虫棉害虫为害,从2000年开始,我     

转基因抗虫棉与抗逆有关的生理特性

为了确定转基因抗虫棉与常规棉生理生化特性的差异,分别对转Bt基因抗虫棉鲁棉研17和新棉33B以及常规棉品种DGL99102和中棉所12号的幼苗期的POD活性、SOD活性、蛋白质含量、游离氨基酸含量、MDA含量、光合色素含量进行比较分析。结果表明：转基因抗虫棉在同样生长条件下其POD和SOD活性均高于常规棉,并且其MDA...     

杀植物线虫的Bt菌Cry蛋白研究进展

植物寄生线虫（Plant parasitic nematodes）对农林业生产造成了巨大的经济损失,为减少环境污染,发展绿色农业,生物防治愈发受到关注。Bt菌（Bacillus thuringiensis, Bt）作为一种重要的生防细菌,对鳞翅目、鞘翅目、双翅目和线虫具有特异性的杀虫活性,对人类和非靶标昆虫无害。文章对已报道的Bt菌及其杀植物线虫Cry蛋白种类、结构特征和杀虫机制等方面研究进展进行了简要综述。     

芬兰人的环保生意经 访芬兰环境科技中国项目委员会总裁Mari Pantsar-Kallio女士、副总裁Ari Makkonen先生及在华首席代表杨凤辉先生

《科学》2008年9月19日卷321 no.5896 Bt抗虫棉抑制中国多个农作物地区的棉铃虫转基因棉花已投入生产的杀虫毒素苏云金杆菌(Bt)和抵御虫害棉铃虫(棉铃虫)已被广泛种植在亚洲。从1992至2007年在中国的棉铃虫数量动态分析了,标注的区域爆发这种虫害的多个作物与种植转Bt基因棉花的关系。     

福建小菜蛾对多位点生物杀虫毒素BtA的敏感性测定

采集福建省 7个地市的小菜蛾于室内饲养 1代 ,用浸叶法测定其 3龄幼虫对杀虫毒素 Bt A及其单体组分即苏云金芽孢杆菌 (Bt)伴孢晶体和阿维菌素 (Avermectin B1)的敏感性差异。结果表明 ,Bt A对不同来源的小菜蛾处理 4 8h的 L C5 0变化范围是 0 .80 - 4.6 7μg/ m L ,与室内种群的 L C5 0比值是 1.18- 6 .85 ,其中以福州、泉州和厦门的 LC50 比值较高。Bt的 L C50 变化范围是 2 .4 2 - 2 3.82 μg/ m L,与室内种群的 L C50 比值是 1.2 2 - 11.97,其中以福州、莆田和厦门的抗性较高。阿维菌素的 LC50 变化范围是 0 .6 6 - 2 .0 0 μg/ m L,与室内种群的 LC50 比值是 1.5 8- 4.70 ,其中福州、莆田和南平的抗性较高。不同地区小菜蛾的繁殖力则无显著差异 ,均在 2 2 0粒 /雌左右。     

苏云金芽孢杆菌营养期杀虫蛋白基因的克隆、表达及杀虫活性分析

选择本实验室分离的野生型苏云金芽孢杆菌菌株WY-197为出发菌株，用全长PCR方法从此菌株中克隆了2．3kb大小的vip3A基因,DNA序列比较发现所克隆的基因vip3A-197与已知的营养期杀虫蛋白基因存在很高的同源性．将基因vip3A-197亚克隆至原核表达载体pET33b构建了原核表达质粒pEVip，转化大肠杆菌BL21，转化子经IPTG诱导后可表达88kD大小的蛋白．该蛋白对甜菜夜蛾(Spodoptera exigua)棉铃虫(Helicoverpa armigera)的初孵幼虫进行生物测定，结果表明，营养期杀虫蛋白vip3A-197对夜蛾科害虫具有一定的杀虫活性。     

几种植物有效成分的提取及杀虫活性研究

对10种植物的有效成分进行了提取,通过对提取物的抑菌试验和杀虫活性试验,筛选出3种较好的Bt菌混剂候选复配植物,还对其中最具开发价值的植物砂地柏进行了不同有机溶剂提取物杀虫活性的比较试验,并确定了石油醚为最佳提取溶剂。     

苍耳不同溶剂提取物对粘虫和蚜虫的杀虫活性研究

通过苍耳不同溶剂提取物对蚜虫和粘虫的杀虫活性测定,证明不同提取溶剂所得苍耳提取物杀虫活性差异显著.各作用方式的杀虫结果表明:苍耳各提取物对粘虫具有很强的拒食活性,对蚜虫的活性较低;同时表明,苍耳的氯仿提取物杀虫活性最好.     

Insecticidal activity of residual Bt protein at the second trophic level

Since the first commercial release of transgenic crop expressing genes from Bacillus thuringiensis (Bt), there have been concerns about its potential impact on the environment. Research has focused on the ecological effects from second exposure to Bt prot…     

Commercial production of transgenic Bt insect-resistant cotton varieties and the resistance management for bollworm (Helicoverpa armigera Hubner)

There are currently three kinds of transgenic Bt insect-resistant cotton germplasm lines, Shanxi 94-24, Zhongxin 94 and R19, in China. They showed high resistance to the neonate larvae of bollworm (Helicoverpa armigera). Transgenic Bt insect-resistant cotton varieties or hybrids have been bred using the three kinds of germplasm lines as parents. Our researches reveal that there exist different expressions in resistant level at different developmental stages in the three categories of germplasm lines. When neonate larvae are fed with leaves of cotton plant at the seeding stage with less than 10 leaves on the main stem, the mortality of the neonate larvae is 100%, but the resistance level will decline at later season. When Bt gene has been transferred to the cotton genome, it can be steadily transferred to the progeny, the level of resistance to bollworm keeps fundamentally uniform. Such insects as tobacco budworm (Heliothis virencens) in laboratory directive selection are very apt to produce resistance to the Bt insecticidal crystal protein. From the present crop system of cotton region in the Yangtze and Yellow River Valleys, and the expression characteristic of transgenic Bt resistant cotton, we suggest that the resistance to toxin protein in bollworm is not apt to be produced if the transgenic Bt insect-resistant cotton varieties are released and grown in the regions except in the Xinjiang cotton region. The managing strategies to delay or retard the resistance are discussed.     

转Bt+CpTI基因抗虫棉品种SGK321性状分析和种质利用

SGK321是以"石远321"为受体,导入Bt CpTI双价抗虫基因后育成的抗虫棉品种。SGK321霜前皮棉产量水平高于常规对照品种,接近杂交对照品种。其早熟性较好,生育期短于对照品种,霜前花率高于对照品种,第一果枝节位适中。抗虫性明显优于一般Bt抗虫棉,三代棉铃虫3龄以上幼虫存活率和幼虫株率与对照相比明显下降;用SGK321棉叶饲养棉铃虫,5龄以下幼虫不能化蛹和羽化;对抗性棉铃虫具有较强的抗虫性,尤其是对大龄幼虫的正常生育阻碍作用明显,对幼虫致死快,致死率高;还可延缓棉铃虫抗性的产生。稳产适应性较好、抗逆性强。具有丰富的遗传基础,一般配合力和特殊配合力较高,2001-2006年6年间作为种质资源被中国众多育种机构利用,已培育出72个双价抗虫棉品种(系),其中24个品种通过国家及省级审定,18个品系参加了各级试验;育成抗虫、抗病、大铃、高衣分、优质等不同类型种质材料237份。对中国棉花生产与品种改良产生了重要影响。     

Transgenic tobacco plants expressing synthetic Cry1Ac and Cry1Ie genes are more toxic to cotton bollworm than those containing one gene

Transgenic tobacco plants carrying Cry1Ac, Cry1Ie or both genes were obtained. In the leaves of transgenic plants carrying both genes, the contents of Cry1Ac and Cry1Ie proteins were 0.173% and 0.131% of the total proteins, respectively. Cry1Ac protein content was 0.182% and Cry1Ie protein con- tent was 0.124% of the total proteins in the leaves of transgenic plants containing only one Bt gene. Fresh leaves of transgenic tobacco and wild-type plants were used for the insect bioassay against wild-type and Cry1Ac-resistant cotton bollworm (Helicoverpa armigera). The bioassay results showed that transgenic plants carrying both genes were significantly more toxic to wild-type and Cry1Ac-resistant cotton bollworm than those carrying Cry1Ac or Cry1Ie alone. This study indicates that the higher toxicity of transgenic tobacco plants carrying both genes is caused by the cooperative function of both Bt proteins, thus providing a potential way to delay the development of insect resis- tance to transgenic crops.     

Transgenic tobacco plants expressing synthetic Cry1Ac and Cry1Ie genes are more toxic to cotton bollworm than those containing one gene

Transgenic tobacco plants carrying CrylAc, Crylle or both genes were obtained. In the leaves of transgenic plants carrying both genes, the contents of CrylAc and Crylle proteins were 0.173% and 0.131% of the total proteins, respectively. CrylAc protein content was 0.182 % and Cry1 le protein content was 0.124% of the total proteins in the leaves of transgenic plants containing only one Bt gene. Fresh leaves of transgenic tobacco and wild-type plants were used for the insect bioassay against wild-type and Cry1Ac-resistant cotton bollworm （Helicoverpa armigera）. The bioassay results showed that transgenic plants carrying both genes were significantly more toxic to wild-type and CrylAc-resistant cotton bollworm than those carrying CrylAc or Crylle alone. This study indicates that the higher toxicity of transgenic tobacco plants carrying both genes is caused by the cooperative function of both Bt proteins, thus providing a potential way to delay the development of insect resistance to transgenic crops.     

Inheritance of resistance to Helicoverpa armigera of 3 kinds of transgenic Bt strains available in upland cotton in China

There are 3 kinds of transgenic Bt strains, Shanxi 94-24, Zhongxin 94, and R19, in upland cotton in China. Their transgenic Bt insect-resistance cultivars or hybrids have been developed and grown by farmers. Genetic studies indicate that the resistance of the 3 transgenic Bt cotton strains to Helicoverpa armigera is controlled by one pair of non-allelic dominant genes. Linkage relationship between the resistant genes of R19 and Shanxi 94-24 transgenic Bt strains shows that they may be inserted in the same chromosome. F₁ hybrids crossed among the 3 strains show that high levels of protection from feeding damage are the same as that of their parents. Therefore, there is no co-suppression phenomenon in many transgenic plants. The results presented here afford a fundamental reliance in developing transgenic Bt insect-resistant cultivars and exploiting the heterosis of hybrids in upland cotton.     

影响抗药性变化几个因子的研究

本文用玻片浸沾法测定棉花红蜘蛛(普通红叶螨—Tetranychus telariusLinn和中华红叶螨T.Chinensis Lo)对E—1059的抗药性变化。试验结果表明,营养条件的变动可以导致抗性的变化,一般杂草上棉叶螨较棉花上的敏感;不同种的敏感性也不同,在棉花上,T.telarius比T.chinensis抗性强;在抗药性的季节性变化中,以7月下旬～8月上旬达到最高峰,8月中旬后又开始下降,形成两头低中间高;在虫体内胆碱酯酶的敏感性,抗性品系降低十分明显,而用E—1059处理后,酶的活性受到不同程度的抑制(从33.3％～100％)。     

Widespread adoption of Bt cotton and insecticide decrease promotes biocontrol services

Over the past 16 years, vast plantings of transgenic crops producing insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) have helped to control several major insect pests and reduce the need for insecticide sprays. Because broad-spectrum insecticides kill arthropod natural enemies that provide biological control of pests, the decrease in use of insecticide sprays associated with Bt crops could enhance biocontrol services. However, this hypothesis has not been tested in terms of long-term landscape-level impacts. On the basis of data from 1990 to 2010 at 36 sites in six provinces of northern China, we show here a marked increase in abundance of three types of generalist arthropod predators (ladybirds, lacewings and spiders) and a decreased abundance of aphid pests associated with widespread adoption of Bt cotton and reduced insecticide sprays in this crop. We also found evidence that the predators might provide additional biocontrol services spilling over from Bt cotton fields onto neighbouring crops (maize, peanut and soybean). Our work extends results from general studies evaluating ecological effects of Bt crops by demonstrating that such crops can promote biocontrol services in agricultural landscapes.     

Can other host species of cotton bollworm be non-Bt refuges to prolong the effectiveness of Bt-cotton?

The potential ecological risks ofBacillus thurigiensis (Bt) insecticides and Bt-crops have caused increasing concern since their commercial release in the field, among which pests’ resistance to Bt-crops is the major ecological risk. Refuge tactic, which can produce sensitive populations, has proved to be a key and sound resistance management strategy in USA and Australia; however, no tactics have been performed in China where Bt-cotton is mostly planted with other host crops of cotton bollworm. Genetic variation and gene flow among different host populations of the cotton bollwormHelicoverpa armigera were analyzed using PCR fingerprinting method. The results show that maize and castor-oil plant, as well as cotton can take effect as refuges to prevent resistance of cotton bollworm to Bt-cotton, while peanut and sesame are not as suitable for planting with Bt-cotton as refuges in the field as low gene flow was detected among populations on peanut, sesame and Bt cotton.     

Polyclonal antibody against an insect excitatory toxin BmKIT from Buthus Martensii karsch and detection of BmKIT expressed in transgenic cotton

An insect excitatory toxin gene from Buthus martensii Karseh （BmKIT） was cloned into the expression vector, pET-28a. BmKIT was expressed as inclusion bodies in Eseherichia coli BL21 （DE3） host cells. The authenticity of in vitro expressed protein was confirmed by Western blot. The inclusion body protein band in SDS-PAGE was excised and the protein, BmKIT, was extracted. Polyelonal antibodies to the purified protein were raised in rabbits. The antibody reacted specifically with the expressed BmKIT and was used to quantify its presence in transgenic cotton.