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1.
The introduction of semi‐dwarfing, high‐yielding and nutrients‐responsive crop varieties in the 1960s and 1970s alleviated the suffering of low crop yield, food shortages and epidemics of famine in India and other parts of the Asian continent. Two semi‐dwarfing genes, Rht in wheat and Sd‐1 in rice heralded the green revolution for which Dr. Norman Borlaug was awarded the Nobel Peace Prize in 1970. In contrast, the revolutionary new genetics of crop improvement shamble over formidable obstacles of regulatory delays, political interferences and public misconceptions. India benefited immensely from the green revolution and is now grappling to deal with the nuances of GM crops. The development of GM mustard discontinued prematurely in 2001 and insect‐resistant Bt cotton varieties were successfully approved for commercial cultivation in 2002 in an evolving nature of regulatory system. However, the moratorium on Bt brinjal by MOEF in 2010 meant a considerable detour from an objective, science‐based, rigorous institutional process of regulatory approval to a more subjective, nonscience‐driven, political decision‐making process. This study examines what ails the regulatory system of GM crops in India and the steps that led to the regulatory logjam. Responding to the growing challenges and impediments of existing biosafety regulation, it suggests options that are critical for GM crops to take roots for a multiplier harvest.  相似文献   

2.
In the past 6 years, the global area of commercially grown, genetically modified (GM) crops has increased more than 30-fold to over 52 million hectares. The number of countries involved has more than doubled. Especially in developing countries, the GM crop area is anticipated to increase rapidly in the coming years. Despite this high adoption rate and future promises, there is a multitude of concerns about the impact of GM crops on the environment. Regulatory approaches in Europe and North America are essentially different. In the EU, it is based on the process of making GM crops; in the US, on the characteristics of the GM product. Many other countries are in the process of establishing regulation based on either system or a mixture. Despite these differences, the information required for risk assessment tends to be similar. Each risk assessment considers the possibility, probability and consequence of harm on a case-by-case basis. For GM crops, the impact of non-use should be added to this evaluation. It is important that the regulation of risk should not turn into the risk of regulation. The best and most appropriate baseline for comparison when performing risk assessment on GM crops is the impact of plants developed by traditional breeding. The latter is an integral and accepted part of agriculture.  相似文献   

3.
The advent of genetically modified crops in the late 1980s triggered a regulatory response to the relatively new field of plant genetic engineering. Over a 7-year period, a new regulatory framework was created, based on scientific principles that focused on risk mitigation. The process was transparent and deliberately sought the input of those involved in crop development from non-governmental organizations, industry, academia and federal research laboratories. The resulting regulations have now been in place for over a decade, and the resilience of the risk-mitigating regulations is evident as there has been no documented case of damage to either environment or human health.  相似文献   

4.
Despite numerous future promises, there is a multitude of concerns about the impact of GM crops on the environment. Key issues in the environmental assessment of GM crops are putative invasiveness, vertical or horizontal gene flow, other ecological impacts, effects on biodiversity and the impact of presence of GM material in other products. These are all highly interdisciplinary and complex issues. A crucial component for a proper assessment is defining the appropriate baseline for comparison and decision. For GM crops, the best and most appropriately defined reference point is the impact of plants developed by traditional breeding. The latter is an integral and accepted part of agriculture. In many instances, the putative impacts identified for GM crops are very similar to the impacts of new cultivars derived from traditional breeding. When assessing GM crops relative to existing cultivars, the increased knowledge base underpinning the development of GM crops will provide greater confidence in the assurances plant science can give on the risks of releasing such crops.  相似文献   

5.
转基因农作物检测技术及其应用与发展   总被引:4,自引:0,他引:4  
常用的转基因检测方法可分为两个方向,一是以检测外源基因为目标,如多聚酶链式反应分析法(PCR),二是以检测外源蛋白为目标,如酶联免疫分析法(ELISA)。此外,近年来,随着世界各国对转基因生物安全问题的日益关注,还涌现出了一批新的检测方法,如微阵列分析法(microarray),色谱分析法(chroma-tography),表面等离子共振(surfaceplasmonresonance,SPR)生物传感器分析法以及近红外线光谱分析法(nearinfraredspectroscopy,NIR)等。将对各种转基因检测方法的原理、特点及研究现状做一个扼要介绍。  相似文献   

6.
【背景】抗除草剂转基因作物是全球种植面积最大的一类转基因植物,以除草剂抗性基因作为检测靶标的分子鉴定方法的研究与应用,对转基因生物安全的检测与监测有重要意义。【方法】根据除草剂抗性基因aad1和dmo的核苷酸序列设计PCR检测引物,并进行PCR反应体系优化、方法特异性、灵敏度、再现性等方面的测试,分别建立aad1基因和dmo基因的特异性PCR检测方法。【结果】建立的PCR检测方法在56~64℃的退火温度范围内均能获得一致性结果,具有良好的稳健性。该方法可将含有aad1基因和dmo基因的转基因作物与其他转基因作物区分开,其灵敏度可分别达到20个拷贝和40个拷贝。通过将aad1基因和dmo基因的检测引物放入同一管PCR反应体系中,还能在一次PCR中同时检测这2个靶标基因,双重PCR的检测灵敏度与单一PCR一致。【结论与意义】建立的分子方法可精准检测出含有aad1基因和dmo基因的转基因作物,具有特异性强、灵敏度高的特点,为抗除草剂转基因作物的筛选检测提供了可靠的技术支撑。  相似文献   

7.
转基因抗虫作物的商业化种植带来了显著的经济、生态和社会效益,对转基因抗虫作物的安全性评价也一直是国内外学者研究的热点。对生物非靶标效应的研究是转基因抗虫作物安全性评价的重要组成部分,农田天敌类生物是其中的重点内容之一。瓢虫是农田生态系统重要的捕食性天敌,评价其在转基因抗虫作物田间是否能通过捕食猎物或取食花粉而接触到杀虫蛋白并富集于体内,进而对自身产生一定的非靶标效应,这对捕食性瓢虫的安全性研究具有重要的意义。本文从捕食性天敌瓢虫的生命表参数、行为功能参数、田间群落参数及体内微环境指标等方面综述了转基因抗虫作物对瓢虫的安全性研究进展,并对后期转基因抗虫作物对田间捕食性天敌的研究方向提出了建议,以期为转基因抗虫作物的环境安全性研究提供理论指导和为进一步完善转基因抗虫作物对瓢虫安全性评价的技术体系提供系统的数据资料。  相似文献   

8.
9.
A key challenge for countries like Ireland up to 2030 is to produce sufficient supplies of food, feed and fuel, without compromising on public health or negatively impacting the environment. As we progress through the technology era, certain agricultural technologies [e.g. genetically modified (GM) crops] have been championed to maximise production while minimising environmental impact. Yet, multiple arguments have been made to counter such a claim, which has led to a polarisation of opinions and a plethora of generic commentaries being made in regard to the impact of this technology. Yet, few studies within the European Union (EU) have conducted a critical needs analysis to assess the potential of specific GM traits in light of issues, such as climate change, increased environmental legislation (e.g. EU Water Framework, Nitrates Directive, proposed reform to the Pesticide Directive and Common Agricultural Policy reform), mitigating biodiversity loss and sustainable biofuel production. The goal of this study is to collate a register of GM traits such that a list of potential GM crops could be prioritised against the backdrop of the challenges facing the tillage sector. Clearly, the crops with the most significant potential for genetic modification are those that are grown widely and/or receive high applications of pesticides and fertilisers (e.g. potato, wheat, barley and maize). GM traits with significant agronomic potential include late blight resistant potato, Fusarium head blight resistant wheat and Septoria resistant wheat and herbicide‐tolerant winter oilseed rape and maize. Following on from these, crops with enhanced nitrogen‐use efficiency could provide significant input to the tillage sector in light of EU‐based restrictions on nitrogen usage, crops with elevated protein content could offset the costs of imported animal feed and crops with modified oil content/lignocellulose composition could assist in biodiesel/bioenergy production at a regional level. This study is relevant to other European countries that cultivate similar crops and like Ireland, are facing multiple challenges to their tillage sector in the near future.  相似文献   

10.
This study assesses the current situation regarding the electronic trade of the Cypriot endemic plants. We examine the plant material sold over the Internet, prices and vendors, and we explore to what extent this activity complies with national laws and international treaties. Overall, 48 taxa (34% of the Cypriot endemic flora) are traded by 21 nurseries of Europe and North America, belonging mostly to Lamiaceae, Brassicaceae, Iridaceae, Asparagaceae, Fabaceae and Asteraceae. Seeds are the commonest form of sale; prices range from €0.12 to 0.79 per seed and from €0.31 to 2.56 per gram. The price range for live plants is €5.67–30.22 (highest for Quercus alnifolia). Among the traded taxa, two are designated critically endangered, another two endangered, four vulnerable, 12 are globally rare and threatened and 12 are protected at the international level. None of the nurseries surveyed seem to have been granted a permit by the authorities of Cyprus to harvest and sell its wild flora, at least during the last decade. State authorities should extend the current legislative framework so as to cover all endemic and nationally threatened taxa, monitor their wild populations, engage in routine surveillance of their e-trade and regulate access to the country’s genetic resources.  相似文献   

11.
12.
Measuring farmland biodiversity is time‐consuming and costly. Operational data from the Farm Scale Evaluation of genetically modified crops project were collated to identify the financial and time costs of each of the 14 protocols used. A subset of 113 of the 266 experimental sites was used. The mean overall cost per site was £19 453 (£ of 2002). Laboratory time was almost 2.5 times that in the field. The most costly protocol was soil surface invertebrates because it required species level identification. The ‘bees and butterflies’ protocol at £418 per site was particularly cost‐effective. The six vegetation protocols accounted for 65% and the six arthropod protocols accounted for 29% of the total costs. The recommended reduction from 12 to 3 transects would have saved £1356 per site, 6% of total budget. A minimalist approach using the single‐season seedbank protocol would cost £3437 per site. The effect of geographical spread of sites on cost was small because of clustering of sites and the large number of protocols. Careful selection of ecological indicators can save considerable resources.  相似文献   

13.
Summary Post-ingestive responses to four different diets containing protein and digestible carbohydrate in balanced (7% protein, 7% digestible carbohydrate or 21% protein, 21% digestible carbohydrate) or unbalanced proportions (7% protein, 21% digestible carbohydrate or 21% protein, 7% digestible carbohydrate) were assessed in fifth stadium Locusta migratoria. Amounts eaten, defaecated and grown were measured across the fifth stadium. Results showed that locusts differentially utilized ingested protein and carbohydrate and consequently achieved similar growth on all four diets despite having ingested very different amounts of protein and carbohydrate. Nutrients in excess of requirements were voided from the animal mainly after digestion and absorption from the gut. In the case of excess nitrogen, a major route for removal was through increased uric acid excretion, while for carbohydrate the major removal mechanism was apparently via respiration.  相似文献   

14.
As the global epicentre of wildlife trade, Hong Kong plays an important role in the preservation or demise of biodiversity, including species found continents away. If mismanaged, legal trade in threatened species can lead to unsustainable exploitation. Inaccurate and incomplete trade records from the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) undermine the regulation of this trade. We examine the trade of hippo (Hippopotamus amphibius) teeth to illustrate the extent of mismatched data between key trading nations. More than 90% of global hippo teeth trade is imported to, and re‐exported from, Hong Kong. Of that imported, over 75% originated in Tanzania or Uganda, but there are notable disparities in declared trade volumes. In most transactions, Hong Kong declares more volume imported than the volume declared exported by Uganda. Overall, Hong Kong has reported the import of 3,176 kg more hippo teeth than declared exported by Tanzania. This indicates that actual trade levels may exceed internationally agreed quotas. In total, over 14,000 kg of hippo teeth is unaccounted for between Uganda and Hong Kong, representing more than 2,700 individual hippos—2% of the global population. This gross discordance in trade data undermines regulatory measures and challenges the persistence of hippo populations in Africa.  相似文献   

15.
16.
Mitochondria of cytoplasmic male sterile crop plants contain novel, chimeric open reading frames. In addition, a number of crops carry endogenous double-stranded ribonucleic acid (dsRNA). In this study, the novel proteins encoded by these genetic components were screened for the presence of potential binding sites (epitopes) of allergy-associated IgE antibodies, as was previously done with transgenic proteins from genetically modified crops. The procedure entails the identification of stretches of at least six contiguous amino acids that are shared by novel proteins and known allergenic proteins. These stretches are further checked for potential linear IgE-binding epitopes. Of the 16 novel protein sequences screened in this study, nine contained stretches of six or seven amino acids that were also present in allergenic proteins. Four cases of similarity are of special interest, given the predicted antigenicity of the identical stretch within the allergenic and novel protein, the IgE-binding by a peptide containing an identical stretch reported in literature, or the multiple incidence of identical stretches of the same allergen within a novel protein. These selected stretches are present in novel proteins derived from oilseed rape and radish (ORF138), rice (dsRNA), and fava bean (dsRNA), and warrant further clinical testing. The frequency of positive outcomes and the sizes of the identical stretches were comparable to those previously found for transgenic proteins in genetically modified crops. It is discussed whether novel proteins from conventional crops should be subject to an assessment of potential allergenicity, a procedure which is currently mandatory for transgenic proteins from genetically modified crops.  相似文献   

17.
Recent seizures of illegally held wildlife indicate a mounting global trade in pangolins involving all eight species. Seizures of illegally traded African pangolins are increasing as wild populations of Asian species decline. We investigated trade in pangolins and law enforcement efforts in Gabon; a country likely to have intact wild populations of three of the four species of African pangolin. We compared village sales and trade chains between 2002‐2003 and 2014. Hunters reported pangolins to be the most frequently requested species in 2014, and the value of pangolins had increased at every point along their trade chain. In Libreville, giant pangolin prices increased 211% and arboreal pangolin prices 73% whilst inflation rose only 4.6% over the same period. We documented a low rate of interception of illegally traded pangolins despite increased law enforcement. Surveys of potential export routes detected exports across forest borders, in conjunction with ivory, but not through public transport routes. We conclude that whilst there is clear potential and likelihood that a wild pangolin export trade is emerging from Gabon, traditional bushmeat trade chains may not be the primary supply route. We recommend adjusting conservation policies and actions to impede further development of illegal trade within and from Gabon .  相似文献   

18.
The importation of infected hosts and the arrival of windborne infected Culicoides (Diptera: Ceratopogonidae) were considered unlikely mechanisms for bluetongue virus (BTV) incursion into a BTV‐free area during the recent BTV serotype 8 (BTV‐8) epidemic in northern Europe. Therefore, alternative mechanisms need to be considered. Air, sea and land transport networks continue to expand, and an important consequence of this is vector‐borne pathogen importation. One important aspect of bluetongue (BT) epidemiology not yet addressed is the potential movement of infected Culicoides via transport and trade networks. Therefore, a risk assessment model was constructed to assess the probability of a BTV outbreak as a consequence of the introduction of Culicoides via these networks. The model was applied to calculate the risk for a BTV‐8 epidemic in Spain in 2007 caused by the introduction of Culicoides from affected northern European countries. The mean weighted annual risk for an outbreak caused by transportation of a single vector from an affected northern European country varied from 1.8 × 10?7 to 3.0 × 10?13, with the highest risks associated with Culicoides imported from Belgium, the Netherlands, Germany and France. For this mechanism to pose a significant risk to BTV‐free countries, a large number of vectors would have to be transported.  相似文献   

19.
随着基因工程技术的运用与发展,越来越多的转基因作物基因污染事件的发生也引起了世界各国对转基因作物与非转基因作物之间的和谐发展问题的高度重视。以美、日、欧为代表,世界各国对转基因作物与非转基因作物的共存问题都进行了积极地探索。借鉴美、日、欧转基因与非转基因作物共存法律制度,以期为我国转基因与非转基因作物共存法律制度的构建提供参考。  相似文献   

20.
Glucosinolates are biologically active natural products characteristic of crucifers, including oilseed rape, cabbage vegetables and the model plant Arabidopsis thaliana. Crucifer‐specialist insect herbivores, like the economically important pest Plutella xylostella (diamondback moth), frequently use glucosinolates as oviposition stimuli. This suggests that the transfer of a glucosinolate biosynthetic pathway to a non‐crucifer would stimulate oviposition on an otherwise non‐attractive plant. Here, we demonstrate that stable genetic transfer of the six‐step benzylglucosinolate pathway from A. thaliana to Nicotiana tabacum (tobacco) results in the production of benzylglucosinolate without causing morphological alterations. Benzylglucosinolate‐producing tobacco plants were more attractive for oviposition by female P. xylostella moths than wild‐type tobacco plants. As newly hatched P. xylostella larvae were unable to survive on tobacco, these results represent a proof‐of‐concept strategy for rendering non‐host plants attractive for oviposition by specialist herbivores with the long‐term goal of generating efficient dead‐end trap crops for agriculturally important pests.  相似文献   

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