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转Bt基因作物是目前商品化进程最快的转基因作物之一,外源Bt基因的导入为培育有效控制有害生物的作物品种提供了新的手段,但外源基因的导入一定程度上改变了作物自身的基因序列,可能引起作物的代谢过程发生改变。本文对转Bt基因作物中导入的Bt基因所产生的杀虫蛋白与作物自身次生代谢物质含量及其效应的关系进行简要综述,结果表明基因的改造和重组已经影响到转Bt基因作物的一些代谢过程。 相似文献
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【目的】转Bt基因植物和Bt菌生物农药释放的Bt毒素是一类具有生物毒性的潜在环境外源污染物，Bt毒素环境行为和生态效应是转基因植物和植物用转基因微生物安全风险评价的重要内容，但是外源Bt毒素对土壤真菌群落和潜在功能的影响还不清楚。【结果】本研究发现，Bt毒素施加量和培养时间均可以显著影响土壤真菌群落组成，且随着Bt毒素施加量增加和土壤培养时间延长，土壤真菌群落差异性逐渐变大。施加Bt毒素提高了土壤真菌群落香农指数和关联网络的负相关性比例及模块数，因而没有对土壤真菌群落的多样性和稳定性产生负面影响。【结论】上述结果表明，评估Bt毒素的环境行为及微生态效应要关注Bt毒素施加量及其长期影响。随着Bt毒素施加量增加，Phymatotrichopsis、Homalogastra、Geosmithia和Apiotrichum等真菌以及参与蛋白质降解、碳素代谢和磷素代谢的功能基因编码酶相对丰度显著升高，推测上述真菌物种和潜在功能参与了Bt毒素在土壤中的降解和转化过程。研究结果为转Bt基因植物、Bt重组菌生物农药以及Bt毒素的生态安全风险评价提供了科学参考和理论依据。 相似文献
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转基因棉种植对土壤氧化还原酶活性的影响 总被引：11，自引：0，他引：11
转Bt基因棉和转Bt+CpTI基因棉及相应非转基因棉的盆栽试验研究表明,转基因作物生长30天时可向土壤中释放Bt杀虫晶体蛋白,而双抗棉种植时CpTI杀虫晶体蛋白的释放量与作物品种有关;转基因棉种植对土壤过氧化氢酶、脱氢酶和硝酸还原酶的活性影响研究表明,生长30天时,与等价基因系非转基因棉相比,转Bt基因棉和双抗棉A的种植并未使三种酶活性发生显著变化,而双抗棉B的种植使土壤脱氢酶活性显著下降。从杀虫晶体蛋白的释放和对酶活性的影响来看,双抗棉B的种植对土壤的生物活性扰动更大。 相似文献
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以转Bt基因棉Bt冀668为材料,室内采用ELISA法,测定粉碎叶、蕾样Bt蛋白在土壤、水中不同时间的残留量以及不同环境处理下的残留量,以研究转Bt基因棉粉碎叶、蕾样Bt蛋白在不同基质中的降解动态以及与环境影响因子的关系.结果显示,粉碎叶、蕾样Bt蛋白分别在熟土、生土和水中前40d、48d取样天数间的残留量差异显著,中... 相似文献
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作物转Bt抗虫基因育种研究进展 总被引：2，自引：0，他引：2
本文概述了Bt抗虫基因的特性及其人工合成和转导技术 ,并根据转Bt基因作物种质的特点和遗传缺陷 ,总结了进行转Bt基因作物育种改良的策略 ,介绍了国内外转Bt基因植株鉴定、筛选技术和育出的优良品系及商业化生产状况 ,讨论了Bt抗虫基因在育种应用中存在的问题及其解决途径 相似文献
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土壤酶活性对大田单季种植转Bt基因及转双价棉花的响应 总被引：6，自引：0，他引：6
利用田间试验,以转Bt基因棉花Z30、转双价（Bt+CpTI）棉花SGK321及其相应的等价基因Z16、SY321作为供试对象,研究棉花种植后对土壤水解/氧化还原酶类活性的影响。结果表明,转Bt棉花及转双价棉花的种植对各种土壤酶活性的影响不一致,转Bt棉花及转双价棉花种植显著降低了土壤蛋白酶和脱氢酶活性(P 0.05)。转Bt棉花还显著降低了土壤脲酶活性(P 0.05);转双价棉花种植同时显著降低土壤磷酸二酯酶、β-葡萄糖苷酶、过氧化氢酶和硝酸还原酶活性(P 0.05)。棉花品种及转基因行为（转入基因类型）均未给土壤酸性磷酸单酯酶和FDA活性带来影响;土壤芳基硫酸酯酶所受的影响主要来自于棉花品种自身。 相似文献
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我国Bt棉花商业化的环境影响与风险管理策略 总被引：23，自引：0，他引：23
吴孔明 《农业生物技术学报》2007,15(1):1-4
Bt转基因棉花于1997年在我国商业化种植，到2006年种植面积已达棉花总面积的70％。环境影响监测表明，Bt棉花有效地控制了棉铃虫和红铃虫的发生和为害，但盲蝽蟓类害虫演化上升成为棉田的主要害虫。抗性分析显示，虽然棉铃虫自然种群对Bt棉花抗性基因频率没有明显的变化，但Bt棉花髙强度种植地区的棉铃虫耐受性正逐年提高，已成为影响Bt棉花持续利用的主要因素。基于Bt棉花环境风险和影响因子的综合分析，本文讨论了Bt棉花环境风险的管理策略。 相似文献
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花药培养获得转Bt基因抗虫水稻纯系* 总被引：3，自引：0，他引：3
采用改良一步成苗法，对转Bt基因水稻(Qryza sativa L.)“克螟稻”与粳稻(O.sativa ssp.japonica)品种秀水63的杂种F1进行花药培养，结果表明：Bt基因不影响花培绿苗分化，但改变绿苗分化进程。对“克螟稻”与秀水63的杂种花培株观察表明，Bt基因按孟德尔规律简单遗传。携带Bt基因与否直接影响花培苗的成活率；潮霉素筛选可增加Bt转基因阳性株的相对比率，但显著降低绿苗率；花培产生的带Bt基因株系与不带Bt基因株系间的农艺性状差异不显著。经培养，成功选育3个抗虫和高产的转基因新品系。 相似文献
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转Bt基因棉种植对根际土壤生物学特性和养分含量的影响 总被引：6，自引：0，他引：6
通过盆栽试验,比较了转Bt基因棉Bt新彩1和Bt基因的受体棉新彩1根际土壤可培养微生物种群数量、酶活性及养分含量的变化。结果表明,Bt新彩1根际土壤可检测到Bt蛋白,且花期达到峰值56.14 ng/g;与对照新彩1相比,Bt#61472;新彩1根际土壤更有利于细菌和真菌的生长和繁殖,放线菌数量没有显著变化。Bt新彩1的根际土壤碱性磷酸酶活性受到抑制,在生长旺盛期脱氢酶活性受到激活,而根际土壤蛋白酶、脲酶和蔗糖酶活性无显著变化;苗期、花期Bt新彩1根际土壤有机质、全氮、速效氮和钾含量没有显著变化,且苗期速效磷含量也没有显著改变,花期其含量显著降低。 相似文献
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Fengxiao Tan Jianwu Wang Zhuona Chen Yuanjiao Feng Guoliang Chi Shafiq Ur Rehman 《Soil biology & biochemistry》2011,43(12):2473-2479
Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) in combination with sequencing of amplified partial 18S ribosomal DNA was used to assess the effects of transgenic Bt corn 5422Bt1 (event Bt 11) and 5422CBCL (event MON810) on the community structure of a non-target microorganism, namely the arbuscular mycorrhizal fungi (AMF) Glomus in corn roots and rhizosphere soils, relative to their non-Bt isolines 5422 (conventional parent) and 5422wx (conventional hybrid). AMF colonization in roots of different corn genotypes was also assessed using microscopic visualization. No adverse effect was detected on the indigenous AMF colonization of the roots of Bt hybrids 5422Bt1 and 5422CBCL. Two-way indicator species analysis (TWINSPAN®) and detrended correspondence analysis (DCA) of the DGGE data from corn roots presented differences between Bt and non-Bt corn isolines (5422Bt1 vs. 5422wx, and 5422CBCL vs. 5422wx). However, differences were also recognized between the two non-Bt corn cultivars (5422 vs. 5422wx), and between the two Bt corn lines (5422Bt1 vs. 5422CBCL) in roots. Our results suggest that corn genotypes may have a greater influence on the AMF community structure of plant roots and rhizosphere soils than other factors, such as the age of the growing plants. 相似文献
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M. Devare 《Soil biology & biochemistry》2007,39(8):2038-2047
Laboratory and greenhouse studies on transgenic Bacillus thuringiensis (Bt) maize have drawn attention to the persistence and activity of the Cry proteins in soil and their potential effects on soil microorganisms, but there have been few field assessments that evaluate the effects of Bt maize with those of insecticides on soil microbial populations. This study was conducted to determine the effects of Cry3Bb Bt maize with those of the insecticide tefluthrin on soil microbial biomass and activity in the field over a 3-year cropping cycle. The recently commercialized maize variety YieldGard® Rootworm (MON863), which produces the Cry3Bb protein, was grown along with a non-Bt isoline with and without tefluthrin applied at planting. Microbial biomass, nitrogen (N) mineralization potential, short-term nitrification rate, and respiration rate were measured in rhizosphere and bulk soil samples collected from three replicate field plots just before planting, at anthesis, and at harvest in each year. There were clear seasonal effects on microbial biomass and activity in the field soils—as represented by the consistent changes in all measured variables across years and sampling times. Differences in the measured variables were also sometimes observed between bulk and rhizosphere soil. However, there were no adverse effects of either the Bt or non-Bt maize with insecticide applied compared to the non-Bt controls; on the contrary, microbial biomass and soil respiration data suggested a stimulatory effect of the Bt genotype, particularly in comparison to the non-Bt isoline. Although ‘higher’ does not necessarily mean ‘better’, the higher microbial biomass and respiration rates observed in the Bt and insecticide-applied soils compared to non-Bt soils does allay concerns that either the Bt protein or the tefluthrin typically used to control the corn rootworm reduce microbial biomass or its respiratory activity in field soils. Similarly, the higher N mineralization potential and nitrification rates observed in some soil samples from the Bt and tefluthrin-treated plots indicate higher activity of N-mineralizing microorganisms, a potentially positive consequence as both ammonium and nitrate are effective N sources for maize during grain filling. Our data suggest that cropping MON863 Bt maize is unlikely to adversely affect soil ecology in the short term. Longer-term monitoring of transgenic cropping systems should assure that the biotic functioning of the soil is maintained as a part of studies on overall ecosystem integrity. 相似文献
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C. X. Sun L. J. Chen Z. J. Wu L. K. Zhou H. Shimizu 《Biology and Fertility of Soils》2007,43(5):617-620
A silty loam soil was incubated with the leaves and stems of two transgenic Bacillus thuringiensis (Bt) cotton varieties and nontransgenic Bt cotton to study the soil persistence of the Bt toxin from the decomposing transgenic
Bt cotton tissues and its effect on soil enzyme activities. The results showed that after Bt cotton tissue amendment, Bt toxin
was introduced into soil upon decomposition; about 50% of the introduced Bt toxin persisted in soil for at least 56 days.
No Bt toxin was detected in the nontransgenic Bt cotton-amended soil; the amount of Bt toxin was the highest in the soil treated
with the residue with the higher Bt toxin content. Activities of soil urease, acid phosphomonoesterase, invertase, and cellulase
were stimulated by the addition of Bt cotton tissues, whereas activity of soil arylsulfatase was inhibited. Probably cotton
tissue stimulated microbial activity in soil, and as a consequence, enzyme activities of soil were generally increased. This
effect can mask any negative effect of the Bt toxin on microbial activity and thus on enzyme activities. 相似文献
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本研究利用三室根箱对棉花根部土壤进行分区采集,以转双价棉SGK321及其亲本常规棉石远321为研究对象,对3个生长时期（播种后40、50 d和60 d）不同根区（S1、S2和S3）土壤速效养分（硝态氮、铵态氮和速效磷）含量及酶（脲酶、碱性磷酸酶和过氧化氢酶）活性变化进行了对比分析。研究结果表明,与常规棉相比,转双价棉的种植促进了S2根区土壤中磷素向有效态的转化,使S2和S3根区土壤硝态氮含量下降,而对各根区土壤脲酶、碱性磷酸酶和过氧化氢酶活性及土壤铵态氮无显著影响。主成分分析结果表明,土壤速效养分和酶活性变化主要受生长时期的影响,转双价棉种植对其影响是非常有限的。 相似文献