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891.
Perspectives on transgenic,herbicide‐resistant crops in the United States almost 20 years after introduction 下载免费PDF全文
Stephen O Duke 《Pest management science》2015,71(5):652-657
Herbicide‐resistant crops have had a profound impact on weed management. Most of the impact has been by glyphosate‐resistant maize, cotton, soybean and canola. Significant economic savings, yield increases and more efficacious and simplified weed management have resulted in widespread adoption of the technology. Initially, glyphosate‐resistant crops enabled significantly reduced tillage and reduced the environmental impact of weed management. Continuous use of glyphosate with glyphosate‐resistant crops over broad areas facilitated the evolution of glyphosate‐resistant weeds, which have resulted in increases in the use of tillage and other herbicides with glyphosate, reducing some of the initial environmental benefits of glyphosate‐resistant crops. Transgenic crops with resistance to auxinic herbicides, as well as to herbicides that inhibit acetolactate synthase, acetyl‐CoA carboxylase and hydroxyphenylpyruvate dioxygenase, stacked with glyphosate and/or glufosinate resistance, will become available in the next few years. These technologies will provide additional weed management options for farmers, but will not have all of the positive effects (reduced cost, simplified weed management, lowered environmental impact and reduced tillage) that glyphosate‐resistant crops had initially. In the more distant future, other herbicide‐resistant crops (including non‐transgenic ones), herbicides with new modes of action and technologies that are currently in their infancy (e.g. bioherbicides, sprayable herbicidal RNAi and/or robotic weeding) may affect the role of transgenic, herbicide‐resistant crops in weed management. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
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为筛选蔗园恶性杂草香附子的理想安全性除草剂,选用20%噻吩磺隆WP和65%甲·灭·敌草隆WP进行田间药效试验.田间试验结果表明:20%噻吩磺隆WP和65%甲·灭·敌草隆WP对蔗园恶性杂草香附子均具有良好的防除效果,是防除蔗园恶性杂草香附子的理想除草剂.20%噻吩磺隆WP最适宜用量为l125 g/hm2(有效成分225 g)、65%甲·灭·敌草隆WP为3 150 g/hm2(有效成分2 047.5 g).2种药剂均可在香附子生长旺盛期(株高10~15cm),按每公顷用药量兑水675 kg进行定向茎叶喷雾,药后15天防除效果可达87.9%以上. 相似文献
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Acidulocomposting recycles food wastes by means of thermophilic lactic acid fermentation. This process can decrease ammonia volatilization and odor emission during processing and produce compost with high nitrogen (N) content. To compare the yield of potatoes (Solanum tuberosum L. ‘Dansyakuimo’) and the suppression of weeds with acidulocompost (AC) and those with conventional composts and inorganic fertilizer (IF), we conducted field experiments in Miyagi Prefecture, northeastern Japan. Potatoes were cultivated in 2008 and 2009 in an Andosol field treated with AC, conventional food waste compost (FWC), poultry manure compost (PMC), cattle manure compost (CMC), IF, or no fertilizer (NF). AC, but not the other treatments, delayed the emergence of potatoes, and suppressed the emergence of weeds, but it did not inhibit potato growth during the late growth stage or yield. Potato N uptake and tuber yield with AC were significantly higher than those with NF and similar to those with FWC, PMC, and IF. The N uptake efficiencies (ratio of difference between N uptake in the treatment and the control to added N) for AC (10.4–12.7% in 2008 and 2009) were similar to those for FWC and PMC (10.2–13.1%), higher than those for CMC (–1.3 to 6.3%), but significantly lower than those for IF (30.2–42.3%). Our findings indicate that AC has an N supply capacity similar to those of FWC and PMC and additionally suppresses the emergence and growth of weeds. 相似文献
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European Non‐native Species in Aquaculture Risk Analysis Scheme – a summary of assessment protocols and decision support tools for use of alien species in aquaculture 下载免费PDF全文
G. H. Copp I. C. Russell E. J. Peeler F. Gherardi E. Tricarico A. Macleod I. G. Cowx A. D. Nunn A. Occhipinti‐Ambrogi D. Savini J. Mumford J. R. Britton 《Fisheries Management and Ecology》2016,23(1):1-11
The European Non‐native Species in Aquaculture Risk Analysis Scheme (ENSARS) was developed in response to European ‘Council Regulation No. 708/2007 of 11 June 2007 concerning use of alien and locally absent species in aquaculture’ to provide protocols for identifying and evaluating the potential risks of using non‐native species in aquaculture. ENSARS is modular in structure and adapted from non‐native species risk assessment schemes developed by the European and Mediterranean Plant Protection Organisation and for the UK. Seven of the eight ENSARS modules contain protocols for evaluating the risks of escape, introduction to and establishment in open waters, of any non‐native aquatic organism being used (or associated with those used) in aquaculture, that is, transport pathways, rearing facilities, infectious agents, and the potential organism, ecosystem and socio‐economic impacts. A concluding module is designed to summarise the risks and consider management options. During the assessments, each question requires the assessor to provide a response and confidence ranking for that response based on expert opinion. Each module can also be used individually, and each requires a specific form of expertise. Therefore, a multidisciplinary assessment team is recommended for its completion. 相似文献
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