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通过探讨秸秆还田与化肥减施下间作绿肥对木薯产量性状的影响,着力解决连作木薯土壤肥力提高与改良相关技术的协调增效。于2019-2020年,以木薯品种“南美1号”为供试材料,设置8个处理,调查每个小区的木薯茎径、叶绿素(SPAD)、块根直径、块根长、单株茎秆鲜重、单株块根鲜重、株高、单片叶重、单株块根数以及小区产量等农艺性状。结果表明,处理5(木薯秆还田+化肥减量12.5%+12.5%营养元素当量黑豆绿肥还田)的木薯产量最高,并得到拟合方程。绿肥秸秆还田以及间作绿肥从整体上改良了土壤肥力,并通过显著影响木薯块根、单片叶重以及单株块根数而影响最终产量。 相似文献
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Jiacheng Zhu Dongfang Cai Jianping Wang Jinhua Cao Yancheng Wen Junping He Lei Zhao Dongguo Wang Shufen Zhang 《中国油料作物学报(英文)》2021,6(2):97-104
Understanding the mechanisms of drought resistance in crop species is crucial for the selection and breeding of tolerant rapeseed (Brassica napus L.) varieties. The present study aimed to assess the physiological and anatomical responses of two rapeseed genotypes, P287 (drought-tolerant) and T88 (drought-sensitive) under three intensities of drought stress. All physiological and anatomical parameters related to drought acclimation were significantly altered in both genotypes under stress conditions. At the fourth-leaf stage, the relative water content, chlorophyll content, protein content, malondialdehyde content, and the activities of peroxidase and catalase in P287 were significantly higher than those in T88, particularly under severe drought conditions. After rehydration, all physiological indexes recovered rapidly, especially in P287. In addition, under drought stress, compared with T88, P287 had thicker palisade tissue, thinner spongy tissue, higher ratio of chloroplast length to chloroplast width, higher stomatal density and stomatal closure rate. Overall, the interaction between physiological and anatomical features improved the drought tolerance of P287 under drought stress conditions. 相似文献
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SUN Tong-xing College of Life Science Biotechnology Yancheng Teachers University Yancheng 《(《农业科学与技术》)编辑部》2008,(4)
The conducting tissue structure of transverse and longitudinal sections was observed on leaves of Podocarpus and Nageia.Results showed:in Podocarpus leaves,there is only one midrib,the xylem tracheid of midrib vascular bundle is multi-form,transfusion tissue belongs to Cycas-type and transfusion tracheids are isodiametric,the accessory transfusion tracheids between palisade tissue and sponge tissue are developed;in Nageia leaves,there are plenty of parallel leaves,the xylem tracheids of each vein are relatively simple,transfusion tissue belongs to Taxus-type and transfusion tracheids are longer in longitudinal section than that in transverse section,the accessory transfusion tissue between palisade tissue and sponge tissue is absent.Considering other differences that in leaves of Podocarpus there are three resin ducts under vascular bundle of midrib,mesophyll cells are differentiated into palisade tissue and sponge tissue;in leaves of Nageia,there is only one resin duct under vascular bundle in each vein and no obvious differentiation in mesophyll cells,palisade tissue can be found on both sides,and sclereids can also be found in mesophyll tissue.The anatomical differences of leaf veins and mesophylls between Nageia and Podocarpus mentioned above support the viewpoint that Nageia and Podocarpus are two independent genera. 相似文献
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本文在对沈阳市农村科技与经济发展现状调查研究的基础上,分析了今后面临的形势,借鉴国内外农村科技发展的道路,提出了发展科学技术,建设高效持久城郊型农业的战略目标,明确了今后发展的指导方针和战略重点,并对实现农村科技发展战略措施进行了探讨。 相似文献
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吴雁程 《农业图书情报学刊》2021,33(12):29-36
[目的/意义]数字素养是终身学习能力的一部分,开展数字素养教育是满足社会和个人发展的需要。然而,中国大学生数字素养教育仍处于起步阶段,尤其在以数字化方式开展相关教育方面仍缺乏较好的实践案例。[方法/过程]文章以英国开放大学图书馆的“数字化生存”项目为研究对象,介绍项目的主要内容和基本思路,总结其主要特点:以简短且吸引人的活动为起点;以深刻且渐进式的路径为纵深;以边界且反思型的自评为节点。[结果/结论]英国开放大学图书馆的“数字化生存”项目简单而有效,为中国数字素质教育的开展提供可行思路:起点较低却富有层次的内容建设;科学合理且循序渐进的设计思路;平易近人且随时反馈的学习体验。 相似文献
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奶牛适宜的温度是8-22℃,如果气温高于25℃.奶牛就会产生明显的热应激反应,食欲减退.呼吸加快,体温增高可达39.3℃以上。 相似文献
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