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991.
无芒春小麦高分子量麦谷蛋白亚基组成分析 总被引:1,自引:0,他引:1
无芒且品质优良的春小麦新品种是在青海省获得大面积推广的重要保障。为充分利用无芒小麦种质资源,利用SDS-PAGE技术对100个无芒春小麦品种的高分子量麦谷蛋白亚基组成进行分析。结果表明,100个无芒品种在Glu-1位点上共有15个等位变异,其中Glu-A1位点3种、Glu-B1位点8种、Glu-D1位点4种;1、7+9、2+12亚基在各自基因位点表达的频率最高,分别为48.0%、37.0%和49.0%,优质亚基1、5+10出现频率均为48.0%,显著高于其他地区有芒和无芒混合在一起的分析结果。在15个等位变异中,发现2个新的高分子量麦谷蛋白等位变异的亚基1Bx6w和1Dy10w。亚基组合类型共有25种,无明显占优势的组合,Null/7+8/2+12、1/7+9/5+10和1/7+8/2+12的频率最高,分别为18.0%、17.0%和10.0%,其他22种组合类型的频率均在10.0%以下;筛选出10个在3个位点均为优质亚基的品种,优质亚基组合为1/7+8/5+10、1/14+15/5+10、1/17+18/5+10、2*/7+8/5+10和2*/13+16/5+10。 相似文献
992.
Quang Dung Le Kotaro Shirai Duc Cu Nguyen Nobuyuki Miyazaki Takaomi Arai 《Water, air, and soil pollution》2009,204(1-4):69-78
In order to understand the present status of heavy metal contamination and the risk associated with human consumption, commercial freshwater eels in Vietnam were examined. The concentration of eight elements (Cr, Mn, Co, Cu, Zn, Sr, Cd, and Pb) was determined in muscle tissue of tropical eel Anguilla marmorata collected in four provinces, Quang Tri, Quang Ngai, Binh Dinh, and Phu Yen, from the central part of Vietnam. Concentrations of Cu, Zn, Cd, and Sr were found to be highest, whereas Co concentration showed the lowest at Quang Tri. Cr was recorded to be lowest in Quang Ngai, while the amounts of Mn and Pb did not vary among locations. Although the metal concentrations in the muscle of A. marmorata did not represent a risk for human consumption, elevated Cd concentrations in Quang Tri related to agriculture activities suggest that further investigations should be undertaken to clarify the potential risk to the eel population. 相似文献
993.
Toan Duc Pham Tri Minh Bui Gun Werlemark Tuyen Cach Bui Arnulf Merker Anders S. Carlsson 《Genetic Resources and Crop Evolution》2009,56(5):679-690
Sesame (Sesamum indicum L.) is a traditional oil crop cultivated throughout South East Asia. To estimate the genetic diversity of this crop in parts
at the region, 22 sesame accessions collected in Vietnam and Cambodia were analyzed using 10 RAPD markers. The 10 primers
generated 107 amplification products of which 88 were polymorphic fragments (83%). Genetic diversity of all populations was
Ht = 0.34 when estimated by Nei’s genetic diversity and species diversity was H′sp = 0.513 when estimated by Shannon diversity index. Genetic distance ranged from 0.03 to 0.43, with a mean genetic distance
of 0.23. The unweighted pair group method with arithmetic averages (UPGMA) cluster analysis for the 22 accessions divided
the material in four groups. The dendrogram revealed a clear division among the sesame accessions based on their geographical
region. Interestingly, some geographically distant accessions clustered in the same group, which might indicate the human
factor involved in the spreading of sesame varieties. The high level of polymorphism shown suggests that RAPD techniques can
also be useful for the selection of parents in sesame (Sesamum indicum L.) breeding program and for cultivar differentiation. 相似文献
994.
Biodiversity conservation does predominantly focus on protected natural areas, but has to consider also the usually Human-dominated matrix in which these natural areas are embedded. Here we study highway stormwater retention ponds, which may act as refuges for native flora and fauna and contribute to the maintenance of biodiversity in Human-dominated landscapes. However, the biodiversity supported by such artificial ponds has received little attention so far. Using standardised methods, we addressed the potential role of highway stormwater ponds as refuges by comparing aquatic macroinvertebrate communities (Coleoptera, Heteroptera, Odonata and Gastropoda) in highway stormwater ponds with ponds in the wider landscape. As expected from their pollutant retention function, highway ponds differed in abiotic conditions from surrounding ponds. However, they supported aquatic macroinvertebrate communities at least as rich and diverse at the family level as surrounding ponds and exhibited similar variability in family community composition and structure. The main difference we observed was a higher abundance of small and/or short-lived invertebrates in the highway ponds. These similar community compositions and structures suggest that highway ponds contribute to the biodiversity of the pond network at a regional scale. Thus, road practitioners should consider highway ponds not only for their hydrological and pollutant retaining purposes but also as a possibility to increase the role of highway verges as a refuge and, consequently, landscape connectivity. The management of these water bodies should recognise their potential for biodiversity especially in Human-dominated landscapes. 相似文献
995.
发达国家食品安全监管研究及其启示 总被引:2,自引:0,他引:2
随着消费者对食品消费要求的不断提高和不安全食品危害事件的频繁发生,食品质量安全管理已日益受到政府、产业界和学术界的关注.由于食品安全管理涉及到多方面、多环节、多层次和多领域的问题,加之我国食品安全监管研究起步较晚,加强这方面问题的研究就显得尤为紧迫.本研究结合国外食品安全监管模式的经验,总结我国食品安全监管的实际情况,探讨在加强监管的过程中应注意的问题,并提出相,缸的对策,以期为尽快构建我国食品安全管理体系提供借鉴. 相似文献
996.
【目的】建立3种N-苯基-N′-硝基苯基脲类化合物的氯甲酸甲酯合成法,并对其生物活性进行测定。【方法】在三正丁胺存在下,硝基苯胺与氯甲酸甲酯加热回流生成硝基苯胺基甲酸甲酯,后者再与过量苯胺反应生成N-苯基-N′-硝基苯基脲,通过优化试验对3种脲类化合物的第2步反应条件进行优化,采用红外光谱和质谱对目标化合物进行结构鉴定。以丰光萝卜种子为材料,采用萝卜子叶扩张生长法测定3种化合物的促细胞分裂活性。【结果】建立的氯甲酸甲酯合成法分2步进行,第1步反应很快,回流30 min即可完成。3种化合物第2步反应的最佳条件:N-苯基-N′-(2-硝基苯基)脲,170℃反应4.5 h,产率85.5%;N-苯基-N′-(3-硝基苯基)脲,152℃反应4.0 h,产率95.0%;N-苯基-N-′(4-硝基苯基)脲,165℃反应5.0 h,产率89.1%。3种化合物在0.01~1.00 mg/L均能明显促进萝卜子叶生长,其中N-苯基-N-′(3-硝基苯基)脲的活性最高。【结论】氯甲酸甲酯法具有设备简单、反应步骤少、后处理简便、产物纯度和收率高等优点,适用于实验室和工业生产。带有吸电子基团的二苯基脲可较好地促进萝卜子叶扩张,同一取代基的活性按间位、对位、邻位依次递减。 相似文献
997.
【目的】明确陕西杨凌大棚油桃出现黄化现象的原因,通过对喷施铁制剂矫正效果的比较,筛选出理想的铁制剂用于果树缺铁黄化病防治。【方法】以陕西杨凌穆家寨发生黄化的大棚油桃为研究对象,采用土壤诊断和叶片诊断等方法确定黄化病的原因,并以清水为对照喷施不同铁制剂(FeSO4、EDTA-Fe、柠檬酸-Fe、腐殖酸-Fe和复合氨基酸-Fe)进行矫治,检测其对油桃叶片叶绿素和有效铁含量及光合作用指标的影响。【结果】油桃黄化的原因是缺铁;不同的铁制剂对油桃黄化的矫治效果有差异,其中以EDTA-Fe、柠檬酸-Fe和复合氨基酸-Fe的处理效果最好,显著提高了油桃叶片的叶绿素和有效铁含量,提高了油桃的净光合速率、单叶水分利用效率和RuBP羧化酶效率。【结论】柠檬酸-Fe和复合氨基酸-Fe是矫治油桃缺铁黄化经济的铁制剂。 相似文献
998.
Quang Huy Hoang Naritaka Kubo Ngan Giang Hoang Hajime Tanji 《Paddy and Water Environment》2009,7(2):123-133
Ba Lai Irrigation Project is located at coastal area in the Mekong Delta. In dry season when the flow rate decreases and the
strong east wind blows into the delta, the salinity intrusion increases and seriously affects agricultural and domestic water
use. Intakes of Ba Lai system have to be closed for 1–3 months depending on their locations, and no water supply during this
period often causes water pollution in the project area. In order to solve such problems, this study aims to seek gate operation
procedures for salinity control and water environment improvement. A numerical model is developed to simulate water movement,
salinity concentration and duration of remaining water (water age) within the system under three scenarios: (1) without control
structures, (2) with available control structures, (3) with the full control structures. Through the numerical simulations,
control structures are confirmed to be an effective measure for the salinity control and suitable gate operation schedules
are proposed to improve the water environment in the project. 相似文献
999.
[目的]研制经济适用的小丑鱼幼鱼人工配合饲料。[方法]利用自制的2种配合饲料和鲜虾肉(对照组)投喂全长2cm左右的克氏双锯鱼和白条双锯鱼幼鱼进行56d的养殖试验,以评价自制配合饲料对小丑鱼生长和色彩的效果。[结果]结果表明,不同饲料(饲料A、饲料B及鲜虾肉)对2种小丑鱼幼鱼生长影响无显著差异,饲料B在饲料A的基础上添加了一定量的虾青素,使用7~10d即具有明显的增色作用,达到了鲜虾所不能达到的着色效果。饲料A和饲料B交替使用比使用鲜鱼虾具有明显的优势。[结论]人工饲料取代鲜活饵料是可行的。 相似文献
1000.
A comparative review of fisheries management experiences in the European Union and in other countries worldwide: Iceland,Australia, and New Zealand
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Paul Marchal Jesper Levring Andersen Martin Aranda Mike Fitzpatrick Leyre Goti Olivier Guyader Gunnar Haraldsson Aaron Hatcher Troels Jacob Hegland Pascal Le Floc'h Claire Macher Loretta Malvarosa Christos D Maravelias Simon Mardle Arantza Murillas J Rasmus Nielsen Rosaria Sabatella Anthony D M Smith Kevin Stokes Thomas Thoegersen Clara Ulrich 《Fish and Fisheries》2016,17(3):803-824
This study compares the details and performance of fisheries management between the EU and a selection of other countries worldwide: Iceland, New Zealand, and Australia, which are considered in many respects to be among the most advanced in the world in fisheries management. Fisheries management in the EU, Iceland, Australia, and New Zealand has developed following different paths, despite being based on similar instruments and principles. Iceland, Australia, and New Zealand have been at the forefront of developing management practices such as stakeholder involvement, legally binding management targets (Australia, New Zealand), individual transferable quotas, and discard bans (Iceland, New Zealand). The EU has since the beginning of the 21st century taken significant steps to better involve stakeholders and establish quantitative targets through management plans, and a landing obligation is gradually being implemented from 2015 onward. The management of domestic fisheries resources in Australia, New Zealand, and Iceland has, overall, performed better than in the EU, in terms of conservation and economic efficiency. It should, however, be stressed that, compared to Australia, New Zealand, and Iceland, (i) initial over‐capacity was more of an issue in the EU when management measures became legally binding and also that (ii) EU has been progressive in developing common enforcement standards, on stocks shared by sovereign nations. The situation of EU fisheries has substantially improved over the period 2004–2013 in the northeast Atlantic, with fishery status getting close to that in the other jurisdictions, but the lack of recovery for Mediterranean fish stocks remains a concern. 相似文献