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排序方式: 共有193条查询结果,搜索用时 15 毫秒
1.
可食性小麦蛋白膜的研究 总被引:7,自引:0,他引:7
本文介绍了小麦蛋白及其成膜特性,总结了国内外可食性蛋白膜的研究现状,提出了可食性小麦蛋白膜的研究方案,并对膜的安全性及其应用作了展望。 相似文献
2.
[目的]以高分1号(GF-1)融合2m卫星遥感影像为基础数据源,结合土地利用现状数据、高分多源遥感影像和地面样方等数据,对冬小麦分类提取中存在的面积误差问题进行研究和分析。[方法]文章以河南省永城市为研究区,在冬小麦提取结果聚类处理基础上,基于线性地物缓冲区数据,采用GIS空间运算实现线性地物面积扣除,接着分析了样方数据和土地利用现状数据再扣除零星地物面积比例上的差异,并采用样方零星地物平均扣除系数对全市各乡镇耕地与非耕地中冬小麦提取面积进行了相关统计和误差分析。[结果]永城市冬小麦最终解译面积11. 29万hm~2,其中线性地物和零星地物扣除面积分别为6 613. 08hm~2和3 875. 22hm~2,占研究区冬小麦解译面积的5. 86%和3. 32%,与统计上报数据相比,其处理前后误差由14. 12%降低至4. 41%,有效地提高冬小麦提取面积精度。[结论]误差来源分析与修正对冬小麦解译面积核算精度具有重要影响,该研究为县级区域尺度下冬小麦面积提取核算提供了思路和借鉴。 相似文献
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Participatory plant breeding began in developing countries and now some European farmers and scientists are proposing its suitability in contributing to sustainable agriculture. This paper uses both genetics and sociology to determine the conditions required. A review of the sustainability of projects implemented in developing countries initiated discussion of an organic durum wheat participatory breeding programme, which is currently being implemented in the south of France. The analysis highlighted the need for the critical participation of experts from different horizons in a socio-technical network. Multi-level interactions and cross-linked learning processes about breeding methods and sociological concepts are needed for effective communication between different stakeholders and scientific disciplines. This approach enables implementation of a range of different action systems in which the production of relevant knowledge and rules addresses the issue of the sustainable development of diverse agro-food systems, rather than the generalization of one model. 相似文献
5.
集成化农产品供应链管理是农产品供应链管理的核心内容,有效的农产品供应链可以解决农产品供应链的链接松弛问题,有助于我国"三农问题"的解决。建立农产品供应链结构模型是集成供应链的首要步骤,分析完全竞争下大宗农产品的特点和农产品供应链过程及关系,构建有效供应链的分析原则,对更有效的农产品供应链建立有借鉴意义。 相似文献
6.
Using wheat market support data from 55 countries for 1961–2011 from the World Bank Agricultural Distortion database, we develop a fixed effect model that shows a more complicated, nonlinear relationship between income and wheat support and its components than previously realised. We find that income generally has a greater effect on border market price support than on domestic price support. Moreover, the difference between these types of support is greater for net importers than for net exporters and has increased with the URAA or WTO accession. Holding other variables constant, the wheat support level of China, driven mainly by border market price support, is projected to rise with future income growth. Meanwhile, Japan is projected to maintain its high level of support, while the US and EU are projected to maintain their lower levels of support. These results are relevant in the context of multilateral trade negotiations, arguing against a narrow focus on past or current policy profiles and for long‐run analyses that might mistakenly rest on the inconsistent assumptions of constant agricultural policies against the backdrop of rising incomes. 相似文献
7.
Prabhakar Adhikari Hailu Araya Gerald Aruna Arun Balamatti Soumik Banerjee P. Baskaran 《国际农业可持续发展杂志》2018,16(1):1-28
With continually increasing demand for food accompanied by the constraints of climate change and the availability and quality of soil and water, the world’s farmers are challenged to produce more food per hectare with less water, and with fewer agrochemical inputs if possible. The ideas and methods of the system of rice intensification which is improving irrigated rice production are now being extended/adapted to many other crops: wheat, maize, finger millet, sugarcane, tef, mustard, legumes, vegetables, and even spices. Promoting better root growth and enhancing the soil’s fertility with organic materials are being found effective means for raising the yields of many crop plants with less water, less fertilizer, reduced seeds, fewer agrochemicals, and greater climate resilience. In this article, we review what is becoming known about various farmer-centred innovations for agroecological crop management that can contribute to agricultural sustainability. These changes represent the emerging system of crop intensification, which is being increasingly applied in Asian, African, and Latin American countries. More research will be needed to verify the efficacy and impact of these innovations and to clarify their conditions and limits. But as no negative effects for human or environmental health have been identified, making these agronomic options more widely known should prompt more investigation and, to the extent justified by results, utilization of these methodologies. 相似文献
8.
Jiayong Song Yu Song 《美中经济评论(英文版)》2006,5(7):41-44,55
The essential parts of Henan wheat economy are production, processing and international trade of high-quality wheat. The initial aspect that affects high-quality wheat development is variety structure. This paper analyzes high-quality wheat's quality structure, variety structure, contribution of them to total yield, and anticipation on wheat production and development of wheat economy in Henan. In conclusion, the result indicates that the high-quality wheat production is on the rise, which presents "s" shape by means of area. Although the overall tendency of high-quality wheat breeding is diversity-oriented, two or three varieties are in a commanding position, especially the "Zheng Mai" series get outstanding contribution during the "10^th Five-year Plan". 相似文献
9.
阿孜古丽·阿布力米提 《粮食流通技术》2016,(16):39-40
黑胚小麦病又被称为小麦黑点病,是一种在小麦胚或其他部位出现变色的病害。文章主要论述了我国在新形势下对黑胚小麦病的研究及其流行规律和病因,同时阐述了新疆粮油产品质量监督检验站在应对黑胚小麦病上的检验措施。 相似文献
10.
[目的]小麦是我国重要的口粮之一,提高小麦的技术效率对于保障粮食安全具有重要的战略意义。在测算小麦技术效率的基础上,找出影响小麦技术效率的关键因素,为保障国家口粮安全提供参考。[方法]基于调研数据,运用超越对数生产函数以及一步随机前沿分析方法,构建计量模型分析土地细碎化和土地质量对小麦技术效率的影响。[结果]全部样本的技术效率差距较大,规模经营农户的技术效率高于小农户,农户技术效率最高的种植面积为67~333hm2,代表小麦种植的适宜规模。从技术效率的影响因素来看,土地细碎化程度和土地质量都对小麦生产的技术效率产生显著影响。[结论]为了提高小麦的技术效率,应该发展多种形式适度规模经营,鼓励创新土地流转形式,提高农业机械化水平; 深入开展土地质量调查,因地制宜地选择土地修复路径; 实行精准补贴,切实保护农民的利益。 相似文献