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A Meta-Analysis of the Impacts of Genetically Modified Crops 总被引:1,自引:0,他引:1
Background
Despite the rapid adoption of genetically modified (GM) crops by farmers in many countries, controversies about this technology continue. Uncertainty about GM crop impacts is one reason for widespread public suspicion.Objective
We carry out a meta-analysis of the agronomic and economic impacts of GM crops to consolidate the evidence.Data Sources
Original studies for inclusion were identified through keyword searches in ISI Web of Knowledge, Google Scholar, EconLit, and AgEcon Search.Study Eligibility Criteria
Studies were included when they build on primary data from farm surveys or field trials anywhere in the world, and when they report impacts of GM soybean, maize, or cotton on crop yields, pesticide use, and/or farmer profits. In total, 147 original studies were included.Synthesis Methods
Analysis of mean impacts and meta-regressions to examine factors that influence outcomes.Results
On average, GM technology adoption has reduced chemical pesticide use by 37%, increased crop yields by 22%, and increased farmer profits by 68%. Yield gains and pesticide reductions are larger for insect-resistant crops than for herbicide-tolerant crops. Yield and profit gains are higher in developing countries than in developed countries.Limitations
Several of the original studies did not report sample sizes and measures of variance.Conclusion
The meta-analysis reveals robust evidence of GM crop benefits for farmers in developed and developing countries. Such evidence may help to gradually increase public trust in this technology. 相似文献5.
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转基因动物食品安全性评价研究 总被引:1,自引:0,他引:1
鉴于转基因动物食品安全性尚未有定论,为加强转基因动物食品安全管理,本文提出了转基因动物食品安全性评价的四原则和五项主要内容,"四原则"是科学原则、实质等同性原则、个案原则、逐步原则;"五项主要内容"是转基因动物本身的特性,转基因动物食品有无毒性和过敏性,转基因动物食品有无激素含量和标记基因,转基因动物食品的售后状况以及其他相关因素,指出了建立一套与国际接轨的适合我国国情的转基因动物食品安全性评价方法是目前我国食品安全领域需要解决的问题. 相似文献
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PCR技术是转基因植物及其产品检测的主要方法,但是因为其对模板纯度和质量有较高要求,对于低质量模板难以获得稳定的检测结果。本研究利用MDA技术可将低至10 copies的微量DNA样品扩增至可用PCR方法稳定检出;进一步利用MDA技术对转基因玉米有证标准物质Bt11粉末的单颗粒痕量样品释出DNA进行扩增,结合PCR扩增检测,玉米粉末颗粒中内源参照基因的检出率达到70%以上,转基因特异性序列检出与内源参照基因检出的比值,与标准物质标称值基本相符,为建立基于MDA技术转基因植物及其产品粉末颗粒等痕量样品检测方法奠定了基础,同时也为加工产品中复合性状转基因作物的检测提供了潜在的解决方案。 相似文献
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Leimanis S Hernández M Fernández S Boyer F Burns M Bruderer S Glouden T Harris N Kaeppeli O Philipp P Pla M Puigdomènech P Vaitilingom M Bertheau Y Remacle J 《Plant molecular biology》2006,61(1-2):123-139
A multiplex DNA microarray chip was developed for simultaneous identification of nine genetically modified organisms (GMOs),
five plant species and three GMO screening elements, i.e. the 35S promoter, the nos terminator and the nptII gene. The chips also include several controls, such as that for the possible presence of CaMV. The on-chip detection was
performed directly with PCR amplified products. Particular emphasis was placed on the reduction of the number of PCR reactions
required and on the number of primers present per amplification tube. The targets were biotin labelled and the arrays were
detected using a colorimetric methodology. Specificity was provided by specific capture probes designed for each GMO and for
the common screening elements. The sensitivity of the assay was tested by experiments carried out in five different laboratories.
The limit of detection was lower than 0.3% GMO for all tests and in general around 0.1% for most GMOs. The chip detection
system complies with the requirements of current EU regulations and other countries where thresholds are established for the
labelling of GMO.
Serge Leimanis, Marta Hernández, Sophie Fernández: These authors contributed equally to this paper. 相似文献
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Brandon R. McFadden 《PloS one》2016,11(11)
There is great uncertainty due to challenges of escalating population growth and climate change. Public perception that diverges from the scientific community may decrease the effectiveness of scientific inquiry and innovation as tools to solve these challenges. The objective of this study was to identify the factors associated with the divergence of public opinion from scientific consensus regarding the safety of genetically modified (GM) foods and human involvement in global warming (GW). Results indicate that the effects of knowledge on public opinion are complex and non-uniform across types of knowledge (i.e., perceived and actual) or issues. Political affiliation affects agreement with science; Democrats were more likely to agree that GM food is safe and human actions cause GW. Respondents who had relatively higher cognitive function or held illusionary correlations about GM food or GW were more likely to have an opinion that differed from the scientific community. 相似文献
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实时荧光定量PCR技术在转基因食品检测领域中的应用 总被引:1,自引:0,他引:1
随着基因工程技术在农业生产中应用的深入,越来越多具有改良特征的转基因植物在全球范围内得到广泛种植,随之而来的转基因食品也迅猛发展,转基因产品大规模商业化引起了对安全性问题的担忧。为保证转基因产品标签制度的顺利实施,建立快速、准确、高通量的定量检测方法十分必要。我们综述了国内外转基因食品检测技术的研究进展,重点阐述了实时荧光定量PCR技术在转基因食品检测领域中的应用,并展望了通过构建质粒标准分子的方法来实现对更多转基因植物品系的定量检测。 相似文献
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Different antibiotic resistance (AR) genes, such as Bla, Tet and NPTII, contaminate commercially available Taq polymerases. The specificity of the AR gene PCR can be increased when using a restriction enzyme-based decontamination of
polymerase. The elimination of Taq polymerase contamination allows the use of PCR tests to screen seeds (corn) and processed food for the presence of genetically
modified organisms (GMO) based on the detection of AR genes. Without a decontamination procedure for AR genes, PCR screening
tests should be interpreted with caution.
Revisions requested 1 November 2005; Revisions received 28 November 2005 相似文献
