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1.
综述了芦笋的营养价值和生理功能,介绍了从植株废弃物中提取芦丁、多糖、菝葜皂甙元、种子油等活性物质的工艺;同时对芦笋种子的营养成分进行了分析评价. 相似文献
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消费者对茶油价值认知不足产生的信息不对称使得茶油市场失灵,潜在的市场需求无法转变为实际的市场需求。调查统计表明,消费者对茶油具有较好的知名度,但却只有较低的价值认知度。影响消费者对茶油价值认知的主要因素包括消费者的性别、学历、收入水平和对健康的关注程度。对茶油价值的认知不再依赖于通过直接的生产地接触获取,也不依赖于经常购买日常食品。根据实证分析可以预测,对茶油价值认知度高的消费者将越来越多,需要通过不断消除居民的性别偏好意识、促进教育资源的平等分配,降低接受高等教育的门槛、促进收入合理分配和不断提高居民对健康的关注水平来促进消费者对茶油价值的认知。 相似文献
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We add to an emerging body of literature on input subsidies in Africa south of the Sahara. Our analysis focuses on demand for seed, characterising smallholders with a high predicted demand for hybrid seed who were not reached by the subsidy programme. We use cross‐sectional data from the 2010 agricultural season and an instrumented control function approach to test the hypothesis that the subsidy on hybrid maize seed in Zambia is selectively biased. Consistent with other literature, we find that the subsidy is a recursive determinant of seed demand, but in 2010, its recipients had more land, more assets, and lower poverty rates. Findings illustrate the social costs of the programme as currently designed and highlight the need to build alternative supply channels if poorer maize growers are to grow hybrid seed. 相似文献
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Jingsong Li Edith T. Lammerts van Bueren Kaijian Huang Lanqiu Qin Yiching Song 《国际农业可持续发展杂志》2013,11(3):234-251
This article explores the potential of involving smallholder farmers in hybrid development for their low-external input farming systems. We have developed a conceptual model of the procedures, based on five assumptions: (a) the hybrids are bred for adaptation to local needs and preferences; (b) the dependence on and need for genetic diversity is taken into account; (c) breeders collaborate closely with farmers also in the initial stages of the breeding programme, that is, in establishing the breeding goals by identifying the desired traits and preferred local populations as (one of the) crossing parents; (d) hybrid seed production can be integrated into the farmers’ local seed system; and (e) farmers and breeders can agree on intellectual property rights, access and benefit sharing in a fair and transparent way. We illustrate the procedural consequences of these assumptions with reference to the case of a participatory maize breeding programme in southwest China, from 2000 to 2012, that included both open-pollinated and hybrid maize improvement. We show how farmers’ early involvement in hybrid development during the pre-breeding stage, including broadening the base populations with farmer-maintained local landraces, can support co-evolution of the genetic resources in farmers’ fields. 相似文献
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[目的]甘肃省农业气候资源丰富,适宜种植的杂粮作物品种较多,但其杂粮种业发展存在诸多与现代农业不相适应的问题,严重制约了杂粮产业的发展,因此急需提出针对甘肃省特色杂粮种业发展的策略。[方法]文章通过实地调研与文献分析,全面系统地分析了杂粮种业的特点和存在问题,并提出了甘肃省特色杂粮种业的发展策略。[结果]调研发现,甘肃省杂粮种子产值高达2亿元以上,其种子研发体系正在完善,商业化速度逐步加快,市场前景广阔。但仍存在杂粮种业缺乏长远规划,杂粮作物种子市场尚不健全,缺乏育繁推一体化的种子企业,种子信息网络及监管机制不健全;育种创新能力有待提高,品种布局不尽合理;杂粮作物品种保护意识不强,对知识产权重视程度不够等诸多问题。因此需要充分发挥甘肃省自然气候生态特点,挖掘优势特色杂粮作物,整合资源,构建杂粮作物育种创新技术体系;建立健全杂粮种子质量监控体制机制;培育现代杂粮种业龙头企业和现代化销售网络等发展策略。[结论]甘肃杂粮作物种业具有广阔的发展空间。 相似文献
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Seed interventions are the major agricultural response during emergency and recovery phases of humanitarian relief. They are implemented by diverse agencies, and widely promoted: for instance the FAO alone managed 400 such projects between 2003 and 2005. However, seed aid suffers from a lack of critical attention, perpetuating widespread myths among practitioners, policymakers, and the larger humanitarian community. This paper challenges five predominant myths about seed aid: (1) seed aid is needed whenever food aid is; (2) seed aid can do no harm; (3) disasters wipe out seed systems; (4) effective implementation is a straightforward logistical exercise, and; (5) improved seed is the best form of aid. These myths are juxtaposed with recent empirical work across a range of countries, particularly in Eastern and Southern Africa. The perpetuation of such myths highlights a serious absence of scrutiny of emergency seed aid, and helps explain why such aid is repeated year after year in many sites, with little apparent positive effect. The paper argues that the invisibility of seed aid is a major cause for the lack of oversight and concludes that donors and farmer beneficiaries must become centrally involved in seed aid governance. 相似文献