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如何提高西瓜的制种效益
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作者 康宇静 《西北园艺(蔬菜)》 2004年第6期9-10,共2页
关键词 西瓜 制种效益 杂交制种 种子质量 生产成本
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两种甘蓝型油菜化杀制种方法对比试验 被引量:3
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作者 宋放 王谧 +1 位作者 宋淑琦 陈杰 《种业导刊》 2016年第1期16-18,共3页
通过试验对两种甘蓝型油菜化学诱导不育(化杀)制种方式:父母本隔厢种植(1厢父本、1厢母本)和2行父本、4行母本育苗移栽的化杀制种效果、效益进行了对比,总结了其优缺点。结果表明,两种方法均可省去喷洒化学杂交剂CHA(ChemicalH ybridizi... 通过试验对两种甘蓝型油菜化学诱导不育(化杀)制种方式:父母本隔厢种植(1厢父本、1厢母本)和2行父本、4行母本育苗移栽的化杀制种效果、效益进行了对比,总结了其优缺点。结果表明,两种方法均可省去喷洒化学杂交剂CHA(ChemicalH ybridizing Agent)时遮挡父本的用工费用,有利于人工或机械喷洒化学杂交剂,但都还存在母本种植比例下降而导致的制种效益降低和制种成本相对升高的问题。若能保留父本(父本做常规种),则父母本隔厢种植撒播化杀制种的方式可降低成本,效益较高;2行父本、4行母本育苗移栽方式提高制种纯度的潜力较大,如能与繁殖小麦种相结合,有潜力成为豫南、鄂北传统杂交油菜制种基地较好的化杀制种方法。 展开更多
关键词 甘蓝型油菜 杂交制种 化学诱导不育 制种成本 制种效益
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Ecological compensation for winter wheat abandonment in groundwater over-exploited areas in the North China Plain 被引量:2
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作者 王学 李秀彬 +3 位作者 辛良杰 谈明洪 李升发 王仁靖 《Journal of Geographical Sciences》 SCIE CSCD 2016年第10期1463-1476,共14页
The land fallow policy was adopted by central and local governments to encourage the abandonment of water-intensive crops, such as winter wheat, in groundwater over-exploited areas. At the same time, since the 1990s, ... The land fallow policy was adopted by central and local governments to encourage the abandonment of water-intensive crops, such as winter wheat, in groundwater over-exploited areas. At the same time, since the 1990s, many households in the North China Plain (NCP) have chosen to replace the winter wheat and summer maize double-cropping system with the spring maize single-cropping system. Therefore, it is crucial to identify target land parcels for winter wheat abandonment and to design reasonable and proper standards for ecological compensation prior to the implementation of the land fallow policy in the NCP. In this study, multi-level Iogit models were used with household survey data in order to detect determinants across land parcel, household and village levels on household cropping system decisions; the opportunity costs for winter wheat abandonment were also calculated using cost-benefit analysis. The results show that: (1) land quality and irrigation condition at parcel level are two essential elements influencing household cropping system decisions. Nearly 70% of the total area of poor land and more than 90% of the total area of unirrigated land has suffered winter wheat abandonment. Target land parcels for the land fallow policy should be those that are irrigated and of high quality. (2) There were no significant differences between net profits from spring maize and summer maize under similar farming conditions, and the opportunity cost for winter wheat abandonment should be equal to the net profit of winter wheat. (3) The primary purpose of the land fallow policy is to induce groundwater recovery and restoration as a preliminary stage. A higher level of 350 yuan/mu is recommended as subsidy for ecological compensation at this stage. Later, the primary purpose of the policy should be a transition to a balance between exploitation and supplementation of water resources, and a lower level of 280 yuan/mu is recommended as a subsidy at this stage. 展开更多
关键词 land fallow ecological compensation multi-level Iogit model opportunity cost groundwaterover-exploited areas
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