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31.
美国·韩国及台湾农业现代化对我们的启示 总被引:2,自引:0,他引:2
发达国家和地区解决农业现代化问题的经验是一笔宝贵的世界遗产,值得仔细地发掘和整理,为我们所用。以美国、台湾和韩国为例分别进行了研究。 相似文献
32.
Jeffery W. Bentley 《Agriculture and Human Values》2006,23(4):451-462
Folk experiments in agriculture are often inspired by new ideas blended with old ones, motivated by economic and environmental change. They tend to save labor or capital. These notions are illustrated with nine short case studies from Nicaragua and El Salvador. The new ideas that catalyze folk experiments may be provided by development agencies, but paradoxically, the folk experiments are so common that the agencies that inspire them usually pay little attention to them. Some folk experiments are original, but others simply copy innovations that farmers have seen somewhere else. Unlike formal scientific research, in which results are consistently written, folk experiments are rarely “inscribed,” because the results are for use by individual farmers and need not be shared with an audience. 相似文献
33.
Traditional Mexican Agricultural Systems and the Potential Impacts of Transgenic Varieties on Maize Diversity 总被引:1,自引:1,他引:1
The discovery of transgenes in maize landraces in Mexico, a center of diversity for this crop, raises questions about the
potential impact of transgene diffusion on maize diversity. The concept of diversity and farmers’ role in maintaining diversity
is quite complex. Farmers’ behavior is expected to have a significant influence on causing transgenes to diffuse, to be expressed
differently, and to accumulate within landraces. Farmers’ or consumers’ perceptions that transgenes are “contaminants” and
that landraces containing transgenes are “contaminated” could cause these landraces to be rejected and trigger a direct loss
of diversity.
Mauricio R. Bellon is a human ecologist working in the Economics Program of the International Maize and Wheat Improvement Center (CIMMYT) in
Texcoco, Mexico. He received his MSc and PhD in ecology at the University of California, Davis. His current research includes
projects that deal with on-farm conservation of maize, gene flow in traditional farming systems, and the impact of improved
germplasm in the livelihoods of poor farmers.
Julien Berthaud is a population geneticist working for the Institut de Recherche pour le Développement (IRD). He received his PhD in plant
science at the University of Paris 11. His current research includes projects related with the dynamics of genetic diversity,
especially in traditional maize farming systems. 相似文献
34.
Antonio C. Allem 《Genetic Resources and Crop Evolution》1994,41(3):133-150
Summary Contrary to views that cassava (Manihot esculenta) is only known in cultivation an argument is made that wild accessions of the species grow over much of the American neotropics, in Brazil, Bolivia, Peru, Venezuela, Guyana, and Surinam. Three subspecies are recognized. M. esculenta subsp. esculenta is the domesticate and includes all cultivars known in cultivation. The wild M. esculenta subsp. peruviana occurs in eastern Peru and western Brazil. The wild M. esculenta subsp. flabellifolia shows a wider distribution and ranges from the central Brazilian state of Goiás northward to Venezuelan Amazonia. The large area of distribution of the two wild subspecies makes it difficult to assign a place of initial domestication. 相似文献
35.
在美国学习和考察期间,充分体验了生物安全三级实验室的建筑设计、管理理念和运行情况,初步了解了美国生物安全三级实验室的运行管理模式,对今后我国兽医实验室的生物安全管理有了新的启发. 相似文献
36.
通过比较中美森林法的历史和现状,指出森林法修改和完善的紧迫性且时机已经成熟,以及森林法修改要重视理论研究和实际情况调查。我国森林法修改和完善可以借鉴美国森林法中的森林生态系统管理等先进理念。对美国《国有林管理法》与《中华人民共和国森林法》的结构与体例、立法精神、科学的地位、公众参与等内容进行了比较研究,据此给出一些《中华人民共和国森林法》的修改建议。 相似文献
37.
脱毒马铃薯氮磷钾肥料效应数学模型的研究 总被引:7,自引:2,他引:5
用3因素5水平12处理回归设计法,设置重复并在小区处理上汲取拉丁方排列的优点以3×4方式布局,使一个试验结果有多个统计组合,择其中R、F值最显著,Se值最小的函数建立回归方程。通过计算机模拟寻优,确定马铃薯产量指标27 000~30 000 kg的优化施肥技术方案为每公顷施纯N:129.22~170.78 kg;纯P2O552.72~68.40 kg;纯K2O 196.65~253.35 kg。 相似文献
38.
调研了美国图书馆学会认可的图书情报学院开设《信息检索》课程情况,如开设该课程的院校、课程名称、课时、课程内容、面向对象等,分析了我国《信息检索》课程教学的现状,针对问题提出了改进建议。 相似文献
39.
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