转Bt基因玉米对亚洲玉米螟的抗性研究

以普通玉米杂交组合N3030为对照,通过田间调查、盆栽接虫试验、室内饲养和组织切片,系统研究了转B t基因玉米杂交组合N3030B t对亚洲玉米螟的抗性表现.结果表明,转B t基因玉米N3030B t上的虫孔率、百株幼虫数、百株隧道数和百株隧道长均极显著低于对照;1-3龄幼虫取食转B t基因玉米后1-2 d死亡,死亡率达90%以上;4龄以后死亡率为0,但其生长发育均受到一定的抑制;组织切片观察表明,亚洲玉米螟幼虫取食转B t基因玉米后,中肠肠壁细胞端部的微绒毛出现不同程度的溶解,大部分肠壁细胞排列松弛,细胞体缩短,细胞层变薄.该结果表明转B t基因玉米对亚洲玉米螟幼虫具有稳定的杀虫作用.     

Susceptibility of Ostrinia furnacalis to Bacillus thuringiensis and Bt Corn Under Long-Term Laboratory Selection

The susceptibility of the Asian corn borer, Ostriniafurnacalis to Bacillus thuringiensis (Bt) formulation and Bt corn was evaluated using insect bioassays for 6 years. Four strains of O. furnacalis were developed by laboratory selection from the laboratory strain reared on a non-agar semi-artificial diet. The RR-1 strain was exposed to a commercial formulation of B. thuringiensis subsp, kurstaki (Btk) incorporated into the artificial diet, the RR-2 strain was exposed to Bt corn (MON810)tissue incorporated into the diet, and the SS-1 and SS-2 strains were reared on the standard diet with or without non-Bt corn tissues material. Decreasing susceptibility of O. furnacalis to Bt and to Bt corn were found in each selected strain although the EDs0 and larval weight fluctuated from generation to generation. The resistance of Bt-exposed strain (RR-1)to Btk increased 48-fold by generation 39; the Bt corn-exposed strain (RR-2) increased its resistance 37-fold to Btk by generation 24. No larvae of SS- 1 survived when they were exposed to the leaves of Bt corn, Bt 11 and MON810. However,2-54% of the RR-1 (generation 46) and RR-2 (generation 20) larvae survived a 3 day-exposure to the leaves of Btl 1 and MON810. The survival of both selected strains on Bt corn silk increased by 10-69%, and the larval weights after many generations selection were increased by 15-22% compared with the unselected susceptible strain. The young larvae were much more susceptible to Bt than older larvae. The highest mortality occurred when the larvae were exposed to Bt at the neonate stage. All of the results suggested that ACB could not only develop resistance to Bt preparation but also to Bt corn. Bt had significant effects on the growth and development of Asian corn borer than on the larval mortality. In order to maintain the long-term effectiveness of Bt pesticide and Bt corn, the resistance management should pay much attention to the larvae that may have opportunities to grow and developed on non-Bt corn or alternate hosts before they attack the Bt corn plants and the survival of larvae after Bt application.     

转Bt基因抗虫玉米对亚洲玉米螟幼虫磷酸酯酶活性的影响

研究了转Bt基因抗虫玉米对亚洲玉米螟幼虫磷酸酯酶活性的影响,结果表明:取食Bt玉米后亚洲玉米螟幼虫体内的酸性磷酸酯酶活性在72 h后显著降低,碱性磷酸酯酶的活性则在24 h后就受到抑制,72 h时酶活与对照组的比值仅为0.3.随着取食时间增长,酶活力减弱,幼虫的体重也显著低于对照,两者存在一定相关性.     

转Bt基因玉米对亚洲玉米螟的抗性评价

转Bt基因抗虫玉米为诺华公司含Bt11转化系的杂交种NX4777,能全株表达Cry1Ab杀虫蛋白,以其非转基因受体玉米品种NX4906为对照。在玉米生长至心叶中期(50~60cm高)、抽雄前期和抽丝散粉期分别进行人工接亚洲玉米螟[Ostriniafurnacalis(Guenée)]初孵幼虫40~60头。以食叶级别、存活幼虫数、蛀孔数、隧道长度和雌穗被害级别等,分别作为评价玉米心叶期和穗期的抗性标准。结果表明,Bt玉米食叶级别仅为1级,显著低于对照的7级。Bt玉米平均每株存活幼虫0.04~0.20头、蛀孔0.11~0.15个、隧道长度0.13~0.41cm,雌穗被害级别为0,植株折茎率为0,而对照玉米平均每株存活幼虫6.19~12.41头、蛀孔4.48~7.05个、隧道长度12.41~24.09cm,雌穗被害级别为5.9,植株折茎率高达73.6%~95.5%。室内生测结果亦表明,取食Bt玉米心叶、雄穗的初孵幼虫3d全部死亡,取食花丝7d死亡率达到99%,相比之下取食常规玉米的存活率在88.7%以上。表明表达Cry1Ab杀虫蛋白的Bt对亚洲玉米螟具有很高的抗虫性,能够保护玉米全生育期免受玉米螟的危害。     

转Bt crylF基因抗虫玉米对亚洲玉米螟幼虫存活率的影响

以不同用量的转Bt crylF基因抗虫玉米饲养亚洲玉米螟幼虫,研究人工饲料中转基因玉米对其存活率的影响.结果表明,随着人工饲料中转基因玉米用量的增加,亚洲玉米螟幼虫的存活率逐渐下降,在用量为100%处理时幼虫存活数仅3～5头,存活率仅15%～20%;在对照玉米处理中,4个处理的幼虫存活数均较高,为16～19头,存活率均在69%以上.转基因玉米处理的幼虫存活数与对照玉米处理相比,两者差异显著.     

转Bt基因抗虫棉的研究进展

对国内外转Bt基因抗虫棉的研究现状、存在问题及对策进行了探讨,其目的是为了正确地理解和认识转Bt基因抗虫棉,使我国的转Bt基因抗虫棉研究与推广工作得以健康发展。     

转Bt基因玉米研究进展

对转Bt基因玉米的研究概况,转化方法,转化体的鉴定方法,遗传评价及存在的问题进行了综述。     

转Bt cry1F基因抗虫玉米对亚洲玉米螟幼虫存活率的影响

以不同用量的转Bt crylF基因抗虫玉米饲养亚洲玉米螟幼虫,研究人工饲料中转基因玉米对其存活率的影响。结果表明,随着人工饲料中转基因玉米用量的增加,亚洲玉米螟幼虫的存活率逐渐下降,在用量为100%处理时幼虫存活数仅3～5头,存活率仅15%～20%;在对照玉米处理中,4个处理的幼虫存活数均较高,为16～19头,存活率均在69%以上。转基因玉米处理的幼虫存活数与对照玉米处理相比,两者差异显著。     

利用Bt试纸对转Bt基因玉米种质的快速检测

玉米是世界三大粮食作物之一,更是重要的饲料作物,并且在世界粮食生产中处于重要的位置,因此转基因玉米的研究和发展受到广泛关注.如何更加安全准确地检测玉米中是否含有转基因,是许多学者一直研究的内容.利用Bt-Cry1Ac/Ab试纸对转Bt基因玉米种质进行检测,初步筛选出含有转Bt基因的玉米种质,同时分析了影响Bt-Cry1Ac/Ab试纸检测的因素.     

美国转Bt基因抗虫玉米研究进展

欧洲玉米螟Ｏｓｔｒｉｎｉａｎｕｂｉｌａｌｉｓ（Ｈｂｎ．）是北美严重影响玉米产量和品质最重要的害虫，转Ｂｔ基因抗虫玉米（以下简称Ｂｔ玉米）的商品化，为控制玉米螟为害提供了新的途径。一、Ｂｔ玉米的培育植物遗传研究人员将选定的外源ＤＮＡ插入玉米植株的ＤＮＡ...     

玉米Bt转基因植株抗虫性鉴定研究初报

经室内喂虫和田间接种,鉴定了Ｍｏ１７,４７８等４个常用自交及其与９１－１－８杂交的抗虫转基因杂种Ｆ１的抗虫性。结果表明,不同转基因材料之间以及同一转基因材料的不同单株间抗虫性差异很大,有少量植株表现高度抗性,个别植株几乎没有抗性。     

南方抗螟玉米种质的引进和推广

从国际玉米小麦改良中心(CIMMYT)引进92份玉米种质材料,从中筛选出对亚洲玉米螟抗性达中抗水平以上的材料46份;对抗性材料进行消化、吸收、创新,组配出丰产性、抗病性和抗螟性均较好的杂交组合桂三5号、桂单26号、桂单30号、CG17和南60-1×CML54等5个组合;在南宁、来宾、百色、河池、防城港等市(区)示范推广桂单26号、桂单30号、桂三5号3个组合,到2002年底,累计示范推广9.007万hm2,增产玉米4771.14万kg,平均每公顷增产529.65kg,新增产值6678.67万元,项目全面超额完成了合同要求的各项技术指标和经济指标,取得了显著的社会效益和经济效益.     

Susceptibility of Ostrinia furnacalis to Bacillus thuringiensis and Bt Corn Under Long-Term Laboratory Selection

The susceptibility of the Asian corn borer, Ostrinia furnacalis to Bacillus thuringiensis (Bt) formulation and Bt corn was evaluated using insect bioassays for 6 years. Four strains of O. furnacalis were developed by laboratory selection from the laboratory strain reared on a non-agar semi-artificial diet. The RR-1 strain was exposed to a commercial formulation of B. thuringiensis subsp. kurstaki (Btk) incorporated into the artificial diet, the RR-2 strain was exposed to Bt corn (MON810)tissue incorporated into the diet, and the SS-1 and SS-2 strains were reared on the standard diet with or without non-Bt corn tissues material. Decreasing susceptibility of O. furnacalis to Bt and to Bt corn were found in each selected strain although the ED50 and larval weight fluctuated from generation to generation. The resistance of Bt-exposed strain (RR-1)to Btk increased 48-fold by generation 39; the Bt corn-exposed strain (RR-2) increased its resistance 37-fold to Btk by generation 24. No larvae of SS-1 survived when they were exposed to the leaves of Bt corn, Bt1 1 and MON810. However,2-54% of the RR-1 (generation 46) and RR-2 (generation 20) larvae survived a 3 day-exposure to the leaves of Bt1 1 and MON810. The survival of both selected strains on Bt corn silk increased by 10-69%, and the larval weights after many generations selection were increased by 15-22% compared with the unselected susceptible strain. The young larvae were much more susceptible to Bt than older larvae. The highest mortality occurred when the larvae were exposed to Bt at the neonate stage. All of the results suggested that ACB could not only develop resistance to Bt preparation but also to Bt corn. Bt had significant effects on the growth and development of Asian corn borer than on the larval mortality. In order to maintain the long-term effectiveness of Bt pesticide and Bt corn, the resistance management should pay much attention to the larvae that may have opportunities to grow and developed on non-Bt corn or alternate hosts before they attack the Bt corn plants and the survival of larvae after Bt application.     

基于文献计量学方法分析中国2005——2009年亚洲玉米螟的研究动态

利用文献计量学方法分析2005-2009年间中文核心期刊上发表的亚洲玉米螟研究论文的数量、发表时间、研究主题、期刊分布、作者单位和资助课题等,探讨我国亚洲玉米螟近年的研究动态.结果表明,玉米螟研究是我国近年的热点课题.2005-2009年间在中文核心期刊上发表相关论文约62篇,其中2007年发表的论文篇数最多(21篇),其次为2009年(17篇);研究关注亚洲玉米螟的生物化学与分子遗传学(32.26％)、防治理论与技术(29.03％)、种群与繁殖行为(16.13％);发表相关论文最多的单位为中国农业科学院(15篇)、沈阳农业大学(11篇)和扬州大学(8篇);论文主要发表在《昆虫学报》(10篇)、《植物保护学报》(9篇)和《玉米科学》(6篇);标注项目资助的论文为56篇,而标注国家自然科学资金资助的论文为25篇.分析结果有助于多角度为读者和作者展示我国亚洲玉米螟研究的现状,为今后深入系统开展玉米螟研究提供参考.     

蜡质芽孢杆菌12-14菌株对苏云金杆菌增效作用的研究

从土壤中分离的Bc1 2 - 1 4菌株是一株对Bt具有明显增效作用的蜡质芽孢杆菌。对Bc1 2 1 4菌株发酵上清液进行增效性测定结果表明 ,该菌株对部分Bt菌株具有明显的增效作用。Bc1 2 1 4菌株上清液对BtHD 1 580菌株增效 ,可提高 82 % ;而Bc1 2 1 4 Bt940 0 1组合 ,与Bt940 0 1纯培养相比 ,在培养基A上的发酵效价和晶体蛋白含量分别为 5 0 0 0IU·μl- 1 、5 4mg·ml- 1 ,提高 1 8%和 2 2 %。     

大豆抗食心虫性遗传研究

利用经多年鉴定出的抗源材料配制杂交组合。根据抗虫亲本及感虫对照品种的抗虫性,制定出本试验的抗虫分级标准,根据此标准对杂交组合的F2代进行分组,并进行遗传类型的适合性测验。结果表明,几个杂交F2均代表现为9∶6∶1的分离特征,适合二对独立显性等位基因积加效应的遗传模式。     

Migratory flight of insect pests within a year-round distribution: European corn borer as a case study

Insect migratory flight differs fundamentally from most other kinds of flight behavior, in that it is non-appetitive. The adult is not searching for anything, and migratory flight is not terminated by encounters with potential resources. Many insect pests of agricultural crops are long-distance migrants, moving from lower latitudes where they overwinter to higher latitudes in the spring to exploit superabundant, but seasonally ephemeral, host crops. The migratory nature of these pests is somewhat easy to recognize because of their sudden appearance in areas where they had been absent only a day or two earlier. Many other serious pests survive hostile winter conditions by diapausing, and therefore do not require migration to move between overwintering and breeding ranges. Yet there is evidence of migratory behavior engaged in by several pest species that inhabit high latitudes year-round. In these cases, the consequences of migratory flight are not immediately noticeable at the population level, because migration takes place for the most part within their larger year-round distribution. Nevertheless, the potential population-level consequences can be quite important in the contexts of pest management and insect resistance management. As a case study, I review the evidence for migratory flight behavior by individual European corn borer adults, and discuss the importance of understanding it. The kind of migratory behavior posited for pest species inhabiting a permanent distribution may be more common than we realize.     

苏云金杆菌深层发酵补料分批培养工艺研究

补料培养与分批培养进行平行对比实验结果 ,补料培养相对于分批培养 ,培养过程Bt最大菌数平均提高了 4 0亿 /ml,晶体含量平均提高了 0 83mg/ml,毒力效价平均提高 1 80 0IU/μl。且补料工艺对生长高峰期溶氧的改善有明显的效果。     

棉铃虫对苏云金芽胞杆菌室内抗性初报

经室内10代筛选,棉铃虫对苏云金芽胞杆菌菌株YBT-1520和HD-73伴胞晶体产生了一定水平的抗性,F10代的抗性指数分别为1.30和2.07。从中可以看出棉铃虫对苏云金芽胞杆菌抗性发展的初步规律,即棉铃虫对多基因毒素(YBT-1520ICPs)的抗性发展比对单基因毒素(HD-73ICPs)的抗性发展速度要慢得多。     

Comparative Analysis of Bacillus thuringiensis Vip3Aa57 and Vip3Aa62 Insecticidal Activities

Bacillus thuringiensis (Bt) exhibits strong insecticidal activity and is harmless to non-target organisms such as human and animals. Bt becomes the most commonly used environment-friendly insecticidal microorganism. However, the insecticidal activities of different Bt strains variy significantly. Therefore, it is particularly important to compare the insecticidal activities of different strains and explore their insecticidal effector mechanisms to expand Bt insecticidal spectrum and enrich transgenic resources. Here, the insecticidal activities of Vip3Aa57 and Vip3Aa62 strains, carrying vegetative insecticidal protein-encoding genes that were inserted into the expression vector pET-21b and transformed into Escherichia coli Rosetta (DE3) strain, expressing 88 ku protein, were compared. Vip3Aa57 protein reportedly displayed body weight inhibition effect on Spodoptera exigua without affecting Heliothis armigera while Vip3Aa62 protein was known to have strong insecticidal activity against S. exigua (LC50=5.124 ng ? mg-1). A low H. armigera activity (LC50=870.1 ng ? mg-1) was observed. The paraffin sectioning results showed that Vip3Aa57 protein affected S. exigua midgut cell morphology. The laser confocal microscopic imaging results showed that Vip3Aa57 bound to receptors in the midgut without damaging the midgut tissue morphology. This study would be conducive for making full use of Bt strains in the soil to compare the insecticidal activities of different Vip insecticidal genes. It could thus provide significant help in revealing the underlying insecticidal mechanisms of Vip3Aa insecticidal genes, developing new insecticidal proteins and delaying pest resistance problems.