浅谈桦树育苗与造林技术

本文介绍了桦树育苗、选种、播种及造林的一些措施和方法。     

四川古蔺河水质的生物毒性评价

随着工农业的快速发展和人类活动的日益增加,大量废水随之产生,这些经过或未经过处理的废水最终排入河流等水体中,对水体水质造成极大的负面影响.该实验应用玉米种子萌发毒性检测和蚕豆根尖微核实验,对四川省泸州市古蔺河8个采水点的水样进行了生物毒性测试.结果显示,沙坝等8个采样点的水样均会导致蚕豆产生一定程度的微核,显示出一定的遗传毒性效应,其中4个采样点的水质达到中污染的水平.玉米种子萌发毒性试验结果表明,永乐镇等5个采样点的水样对于玉米种子的发芽率和根生长有比较明显的抑制作用.这表明古蔺河下游水质受到污染,有潜在生物毒性.     

The potential of participatory hybrid breeding

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.     

脂肪干细胞在组织工程中的研究进展

随着组织工程技术的不断发展,种子细胞的来源问题已经成为制约其发展的一个重要的因素,,自脂肪间充质干细胞发现以来,人们对其的研究不断深入。近几年,越来越多的实验证实,脂肪间充质干细胞可以向成骨细胞、成软骨细胞、神经细胞、肌细胞和脂肪细胞等不同胚层来源的细胞分化。而且脂肪组织来源广泛、取材容易、便于自体移植：脂肪间充质干细胞在体外长期培养的过程中始终保持其多向分化潜能、遗传背景相当稳定、体内植入后少有免疫排斥的问题,因而是一种非常理想的组织工程种子细胞。     

现代林业集约化森林经营的思考

实行森林经营集约化是缓解森林资源危机的科学途径;反思林业机构设置对现代林业建设的影响;提出森林经营的关键在于把林况和经营措施落实到山头地块,编好和严格执行森林经营方案;小班林木经营的好坏,决定集约化森林经营的成败。     

甘肃省杂粮种业现状、存在问题与发展策略探讨

[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。     

安徽省亳州市小麦产业现状与发展策略研究

目的 亳州市位于黄淮麦区,是安徽省小麦种植面积第二大地市,亳州小麦产业化发展对安徽省至关重要,总结亳州小麦产业发展现状,分析其存在的主要问题,为亳州小麦产业化发展提供建议。方法 文章通过对亳州小麦产业和加工企业进行实地调查,委托亳州市农业局和农业科学院组织主题为小麦生产和消费的座谈会,收集小麦种植品种、种植面积以及产量等相关数据,分析小麦产业化发展现状及现存主要问题。结果 亳州市形成以优质强筋小麦、中强筋小麦、中筋小麦为主,弱筋小麦为辅的种植结构,2019年优质专用小麦种植面积占小麦总面积69%。现有规模化面粉企业28家,合计年加工小麦约200万t,消费当地近60%的小麦。小麦产业发展过程中存在“农业合作社规模较小,种植规模和专业技能不足”“订单农业较少,小麦优质不优价”“面粉企业规模较小,下游食品加工企业少”“产业链间的融合不够紧密”等问题。结论 提出“构建大规模小麦加工体系,发挥龙头企业的产业带动作用”“发展农业专业合作组织,实现规模化、标准化、专业化种植”“研发优质品种配套栽培技术,实现良种良法”“打造优质专用小麦生产示范区,培育区域品牌”等策略建议。     

An assessment of the policies and practices of selective logging and timber utilisation: A case study from natural forests of Tarai Nepal and Queensland Australia

Selective logging (SL) contributes nearly 15 percent of the global timber needs. Considering its role in sustainable timber production, biodiversity conservation and forest carbon enhancement, assessment of SL policies and practices is crucial. This paper assesses the policies and practices of SL in natural production forests of the Tarai region of Nepal and Queensland Australia to explore the key differences in such policies and practices and their possible implications in achieving sustainable forest management objectives. The primary methods applied in the study were review and synthesis of key policy documents and qualitative analysis of the information gathered from key informant interviews and stakeholders’ workshop. Altogether, 53 respondents from a wide range of stakeholder groups (government organizations-15, non-government organizations/networks-15, private sector including the individual landowners-13, local political leaders-3 and independent forest experts/scientists-7) were consulted. Findings suggest that: (1) frequent and inconsistent changes in policy provisions, lengthy administrative procedures and heavy engagement of state forest agencies in forest product harvesting and sales processes play key roles in sub-optimal forest production in Nepal, whereas lower dependency on forest-products, higher labour costs, lack of species-wise royalty rate and flexibility in selecting optional logs are the key factors for increased wastages of forest products in Queensland; (2) recovery and utilisation of the harvested forest product is better in Nepal but policy and practical considerations on biodiversity and environment are better in Queensland; and (3) Forest harvesting specific codes of practice, occupational health and safety standards, and their compliance mechanism of Queensland could be beneficial for Nepal to minimise operational harvesting risks and to attract professional harvesters that support promoting sustainable use and management of natural forests, as we found this aspect almost neglected in Nepal.     

A Case of Mistaken Identity? Measuring Rates of Improved Seed Adoption in Tanzania Using DNA Fingerprinting

Studies of improved seed adoption in developing countries are almost always based on household surveys and are premised on the assumption that farmers can accurately self-report their use of improved seed varieties. However, recent studies suggest that farmers’ reports of seed varieties planted, or even whether the seed is local or improved, are sometimes inconsistent with the DNA fingerprinting results of those crops. We use household survey data from Tanzania to test the alignment between farmer-reported and DNA-identified maize seed types planted. In the sample, 70% of maize seed observations are correctly reported as local or improved, while 16% are type I errors (falsely reported as improved) and 14% are type II errors (falsely reported as local). Type I errors are more likely to have been sourced from other farmers, rather than formal channels. An analysis of input use, including seed, fertiliser, and labour allocations, reveals that farmers tend to treat improved maize differently, depending on whether they correctly perceive it as improved. This suggests that errors in farmers’ seed type awareness may translate into suboptimal management practices. The average yield of seed that is correctly identified as improved is almost 700 kg per hectare greater than that of type I errors. This indicates that investments in farmers’ access to information, seed labelling, and seed system oversight are needed to complement investments in seed variety development.     

大竹巴山红香椿发展探讨

大竹县有500多年栽培巴山红香椿的历史。县政府联合林业部门积极的促进巴山红香椿的种植与推广，不仅仅改善了宣传推广形式，扩大了巴山红香椿的影响范围，用灵活的种植服务形式提高了农户的积极性，还通过科学规划，合理布局，对巴山红香椿的种苗质量进行严格把关，从总体上提高了造林成效。从大竹县促进巴山红香椿的实际入手，分析了大竹县红香椿经济发展现状，并对其在发展过程中所采取的策略进行了解读，提出再发展建议。