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1.
丛枝菌对转Bt基因棉根际土壤营养物质及酶活性的影响   总被引:1,自引:0,他引:1  
尹念辅  杨兵  李铁松  戈峰 《环保科技》2013,(5):35-39,42
转Bt基因抗虫棉已在全球范围内广泛种植,然而Bt棉根际分泌物是否会影响土壤理化性质及土壤功能尚缺乏深入研究。通过盆栽实验方法,设计不同的棉花品种与是否接种丛枝菌总共4个处理,以此研究Bt棉和接种丛枝菌根真菌对植物根际土壤营养物质含量以及土壤酶活性的影响。结果显示:丛枝菌可以使non-Bt棉和Bt棉根际土壤营养物质中的土壤有机质和土壤总氮含量显著增加,但是对根际土壤全磷却鲜有影响。转基因对于不同品种棉花根际土壤酶,丛枝菌均能有效增强其活性。由此表明,丛枝菌对Bt棉和non-Br棉根际土壤环境均具有改善作用。  相似文献   
2.
Soil properties, microbial communities and enzyme activities were studied in soil amended with replicase (RP)-transgenic or non-transgenic papaya under field conditions. Compared with non-transgenic papaya, significant differences (P〈0.05) were observed in total nitrogen in soils grown with transgenic papaya. There were also significant differences (P〈0.05) in the total number of colony forming units (CFUs) of bacteria, actinomycetes and fungi between soils amended with RP-transgenic plants and non-transgenic plants. Compared with non-transgenic papaya, the total CFUs of bacteria, actinomycetes and fungi in soil with transgenic papaya increased by 0.43-1.1, 0.21-0.80 and 0.46-0.73 times respectively. Significantly higher (P〈0.05) CFUs of bacteria, actinomycetes and fungi resistant to kanamycin (Km) were obtained in soils with RP-transgenic papaya than those with non-transgenic papaya in all concentrations of Km. Higher resistance quotients for Km' (kanamycin resistant) bacteria, actinomycetes and fungi were found in soil planted with RP-transgenic papaya, and the resistance quotients for Km' bacteria, actinomycetes and fungi in soils with transgenic papaya increased 1.6-4.46, 0.63-2.5 and 0.75-2.30 times. RP-transgenic papaya and non-transgenic papaya produced significantly different enzyme activities in arylsulfatase (5.4-5.9x), polyphenol oxidase (0.7-1.4x), invertase (0.5-0.79x), cellulase (0.23-0.35x) and phosphodiesterase (0.16-0.2x). The former three soil enzymes appeared to be more sensitive to the transgenic papaya than the others, and could be useful parameters in assessing the effects of transgenic papaya. Transgenic papaya could alter soil chemical properties, enzyme activities and microbial communities.  相似文献   
3.
Earthworm toxicity tests are useful tools for terrestrial risk assessment but require a hierarchy of test designs that differ in effect levels (behavior, sublethal, lethal). In this study, the toxicity of chlorpyrifos contaminated soil on earthworms was assessed. In addition to the acute and chronic tests, an avoidance response test was applied. Earthworms were exposed to sublethal and lethal concentration of chlorpyrifos, and evaluated for acute toxicity, growth, fecundity and avoidance response after a certain exposure period. The test methods covered all important ecological relevant endpoints (acute, chronic, behavioral). Concentration of 78.91 mg/kg, chlorpyrifos caused significant toxic effects in all test methods, but at lower test concentrations, only significant chronic toxic effects could be observed. In the present study, chlorpyrifos had adverse effect on growth and fecundity in earthworm exposed to 5 mg/kg chlorpyrifos after eight weeks. The avoidance response test, however, showed significant repellent effects concentration of 40 mg/kg chlorpyrifos. For chlorpyrifos, concentration affecting avoidance response was far greater than growth and fecundity, it seemed likely that earthworms were not able to escape from pesticide-contaminated soil into the clean soil in field and hence were exposed continuously to elevated concentrations of pesticides.  相似文献   
4.
针对传统交通事故动态分析法在交通肇事逃逸案件侦查中投入高、效率低、精度差的缺点,笔者在信息主导警务理念的指导下,综合运用逻辑学、系统科学、社会学、心理学、情报科学相关原理,动态分析交通事故现场的痕迹、车辆行驶轨迹、道路交通环境、警情综合信息、驾驶人行为与逃逸心理,以及受害者损伤特征,准确掌握车辆或驾驶人局部特征,从而为侦破交通肇事逃逸案件提供精确的查缉信息,使警务行动实现精确用警、快速反应和精确打击的目标。笔者给出了利用动态分析法侦破交通肇事逃逸案件的流程和步骤;指出提高办案水平,迫切需要加强警务信息和社会信息的有效融合,研发专门系统,强化信息研判。  相似文献   
5.
In 2001, it was announced thattransgenic DNA had introgressed intotraditional strains of maize in Mexico. Acontroversy erupted and raged throughout 2001and 2002. This episode represents an acutebreakdown in scientific discourse. Given thestakes in the genetically modified organismdebate, a breakdown in scientific discourse isalarming. The following inquiry looks into thecauses of this breakdown. Ultimately, it willbe argued that the underlying problem is thecurrent institutional structure of science,particularly in the United States. If thediagnosis is correct, then the proper course oftreatment is to pursue a program ofinstitutional reconstruction.  相似文献   
6.
Transgenic plants are now being used to develop pharmaceutical and industrial products in addition to their use in crop improvement. Using confinement requirements, these transgenic plants are grown and processed under conditions that prevent intermixing with commodity crops. Regulatory agencies in the United States have provided guidance of zero tolerance of these new industrial crops with commodity crops. While this is a worthy goal, it is theoretically unattainable. In spite of the best containment practices, there is a potential risk using any system of production due to unforeseen incidences including natural disasters or exposure to workers. The precautionary principle has been used for numerous regulated articles in addressing the potential risks of new products and technology based on a risk assessment in similar situations. We present here a risk assessment model that could be used as a start to develop an accepted model for the industry. The model is based on current risk models used for other regulated articles, but adapted for these types of products. This could be used to determine action levels in the event of an unintended exposure or to ensure that detection or confinement methods are adequate to avoid risks. As an example, aprotinin, a therapeutic protein now being produced in maize, was evaluated for potential risk to humans using this model.  相似文献   
7.
以湖北武汉、随州、武穴和孝感以及山东德州5个多年转基因水稻种植区为试验地,在水稻生育期采集转cry1 Ab/c基因水稻Bt汕优63(Bt-SY63)和对照非转基因汕优63(SY63)稻田水体和土壤,使用酶联免疫吸附测定(ELISA)方法对稻田水体和土壤Cry1 Ab/c蛋白残留量进行动态监测.结果显示,与SY63稻田相比,连续种植2~4 a后,不同生育期Bt-SY63稻田水体Cry1Ab/c蛋白残留量大多与同一生育期SY63样品间差异未达显著水平(P>0.05),最高残留量为0.373 ng· mL-1.与水体Cry1Ab/c蛋白残留情况相似,不同生育期Bt-SY63稻田土壤Cry 1Ab/c蛋白残留量大都低于试剂盒检测限(0.25 ng·g-1),仅随州苗期、德州拔节期和开花期样品有微量残留,鲜土残留量分别为0.261、0.540和0.361 ng·g-1,并分别与SY63样品间差异显著(P<0.05).另外,多年连续种植Bt-SY63水稻后,2、3和4a种植年限的Bt-SY63稻田水体和土壤中Cry1Ab/c蛋白残留量之间大都没有显著差异(P>0.05).认为连续种植2、3和4a的Bt-SY63水稻稻田水体和土壤仅存在微量Cry1Ab/c蛋白残留,不会造成Cry1Ab/c蛋白在稻田水体和土壤中的累积.  相似文献   
8.
Fine particulatematter (PM2.5) is associated with increased risks of Alzheimer’s disease (AD),yet the toxicologicalmechanisms of PM2.5 promoting AD remain unclear. In this study,wildtype and APP/PS1 transgenic mice (AD mice) were exposed to either filtered air (FA) or PM2.5 for eight weeks with a real-world exposure system in Taiyuan, China (mean PM2.5 concentration in the cage was 61 μg/m3). We found that PM2.5 exposure could remarkably aggravate AD mice’s ethological and brain ultrastructural damage, along with the elevation of the pro-inflammatory cytokines (IL-6 and TNF-α), Aβ-42 and AChE levels and the decline of ChAT levels in the brains. Based on high-throughput sequencing results, some differentially expressed (DE) mRNAs and DE miRNAs in the brains of AD mice after PM2.5 exposure were screened.Using RT-qPCR, seven DEmiRNAs (mmu-miR-193b-5p, 122b-5p, 466h-3p, 10b-5p, 1895, 384–5p, and 6412) and six genes (Pcdhgb8, Unc13b, Robo3, Prph, Pter, and Tbata) were evidenced the and verified. Two miRNA-target gene pairs (miR-125b-Pcdhgb8 pair and miR-466h-3p-IL-17Rα/TGF-βR2/Aβ-42/AChE pairs) were demonstrated that they were more related to PM2.5-induced brain injury. Results of Gene Ontology (GO) pathways and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways predicted that synaptic and postsynaptic regulation, axon guidance, Wnt, MAPK, and mTOR pathways might be the possible regulatory mechanisms associated with pathological response. These revealed that PM2.5- elevated pro-inflammatory cytokine levels and PM2.5-altered neurotransmitter levels in AD mice could be the important causes of brain damage and proposed the promising miRNA andmRNA biomarkers and potentialmiRNA-mRNA interaction networks of PM2.5-promoted AD.  相似文献   
9.
研究了转cry1Ab基因水稻(克螟稻)中Cry1Ab毒蛋白的表达、根系分泌及其在土壤中的残留规律.结果表明,分蘖始期至成熟期,克螟稻地上部和根部中的Cry1Ab毒蛋白的表达量(FW)分别为3.23~8.22 μg/g和0.68~0.89 μg/g.生育期间克螟稻根系分泌的Cry1Ab毒蛋白含量仅为1.66~48.02 ng/(株·d).试验证实,克螟稻根际土中的Cry1Ab毒蛋白残留含量低于检测限(<0.5ng/g 干燥土).生物测定还表明,克螟稻根际土及其提取液对棉铃虫初孵幼虫和3龄幼虫不产生致死性效应.相对于Cry1Ab毒蛋白的根系分泌转移,克螟稻秸秆还田对土壤环境的影响应引起重视.  相似文献   
10.
转Bt-cry1Ac棉花花粉对意大利蜜蜂生长发育的影响   总被引:3,自引:1,他引:3  
研究了取食转Bt-cry1Ac棉花花粉对意大利蜜蜂的影响,主要包括意大利蜜蜂的生长发育、体内酶活性的变化.结果发现,取食转Bt-cry1Ac基因棉花花粉的意大利蜜蜂与取食非转基因亲本棉花花粉的蜜蜂(CK)相比,4、5、6日龄幼虫体重差异不显著,幼虫及蛹的历期也没有明显差异.取食转Bt-cry1Ac基因棉花花粉的意大利蜜蜂6日龄幼虫体内的谷胱甘肽-S-转移酶、总蛋白酶活力与CK相比,没有显著差异.取食转Bt-cry1Ac基因棉花花粉的意大利蜜蜂幼虫体内的α-乙酸萘酯酶、乙酰胆碱酯酶活力极显著高于CK,强碱性、弱碱性类胰蛋白酶活力极显著低于CK,类胰凝乳蛋白酶活力显著低于CK.另外,采用酶联免疫(ELISA)方法在取食转Bt-cry1Ac基因棉花花粉的蜜蜂6日龄幼虫体内能够检测到Bt杀虫蛋白.表4参12  相似文献   
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