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941.
对西洋杜鹃(Rhododendron hybridum)2个品种(Redjack、Brittania)的试管苗在恒温和变温变光培养条件下进行了离体培养。结果表明,变温变光培养较恒温培养更适于西洋杜鹃的壮苗及生根;2种不同培养条件下的幼苗移栽成活率分别为90.8%和71.0%,差异显著。 相似文献
942.
荷兰等设施园艺技术先进国家通过高投入、高产出、高效益的理念,走出了一条先进、高效的设施园艺生产路线。我国设施园艺近年也得到了快速发展,设施园艺种植面积逐年增加,目前在世界的占比已达80%以上。但是,与荷兰、美国、以色列等先进国家的设施园艺生产相比,我国园艺设施90%以上为简易温室,种植对象90%以上是蔬菜,设施生产技术水平低、产出效益低,设施园艺的技术优势未能有效发挥。本文针对园艺生产设施内种苗生产、无土栽培生产等方面相关的机械化、自动化生产装备发展现状进行分析,总结了我国设施园艺生产特点、生产装备的发展现状及存在的问题,并对我国设施园艺生产作业装备的发展提出了建议。 相似文献
943.
地域特色可以通过自然景观和文化景观2方面来体现。文中从青岛市崂山路滨海景观设计案例入手,讨论了滨海景观设计如何突出地域特色的问题;通过挖掘基地的自然和文化景观资源,从自然景观和文化景观营建2个方面探讨了崂山滨海景观大道的地域特色营建手法。文化景观主要突出道家文化主题,在设计手法和设计细节处体现文化要素;自然景观突出山、海自然环境特色,利用现状自然特征处理滨海与山体景观界面,最终实现凸显地域特色的滨海景观长廊的设计目标。 相似文献
944.
Xing Zheng Siqi Lin Rui Yang Jianguang Qin Aimin Wang Zhifeng Gu Zhenhua Ma 《Aquaculture Research》2019,50(6):1678-1686
A study on Chlamys nobilis sperm cryopreservation by a programmable freezing method was conducted under laboratory condition. Four cryoprotectant agents (dimethyl sulfoxide [DMSO], methanol [MET], propanediol[PG] and ethylene glycol [EG]) and four concentrations (5%, 10%, 20% and 30%) were evaluated for their ability to retain sperm motility, movement characteristics and fertility. Results showed that cryopreserved sperm total motility produced by DMSO and MET at 5%, 10% and 20% were higher than other cryoprotectant treatment groups (CPA groups), as well as rapid sperm percentage. The curvilinear (VCL) and straight line (VSL) velocity produced by DMSO at 5% significantly higher than other CPA groups (p < 0.05), while no significant differences were found for average path (VAP) velocity. The lateral head displacement (ALH) in all CPA groups was similar and without significant difference (p > 0.05), as well as the beat‐cross frequency (BCF). A significant higher fertilization rate was produced in DMSO than that in MET at same concentration (p < 0.05), and no significant differences were found for differing concentrations of the same cryoprotectant (p > 0.05). Overall, 5%‐20% DMSO was more suitable for Chlamys nobilis sperm programmable cryopreservation when the calcium‐free Hanks’ balanced salt solution was used as the extender, and 10°C/min from 0°C to ?80°C was used as freezing rate. The findings presented in this study will benefit conservation programs for Chlamys nobilis. 相似文献
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948.
为了贯彻落实《国务院关于促进节约集约用地的通知》,切实加强开发区用地管理、促进开发区节约集约用地并为开发区扩区升级提供科学依据,运用调查研究及模型分析方法,以海南国际科际工业园为研究对象,从土地利用状况、用地效益和管理绩效3个方面构建土地集约利用评价指标体系,对开发区土地进行集约利用评价研究。结果表明:国科园土地集约利用水平总体很高,土地利用状况良好,管理绩效突出,但用地效益一般。海南国际科际工业园要实现土地集约利用,应该结合海南国际旅游岛建设,创新管理体制,建立项目准入制度和退出机制,进一步改善投资环境,大力推进生态园区建设。 相似文献
949.
Jie Li Rongyue Zhang Yinhu Li Chaohua Long Wengfeng Li Hongli Shan Wenjie Lu Yingkun Huang 《Plant pathology》2023,72(1):89-99
Brown stripe disease is a severe foliar fungal disease of sugarcane worldwide and is widespread in all sugarcane planting areas in China. Brown stripe is a major disease that seriously affects the output and quality of the sugarcane industry in Yunnan Province, China's second-largest sugar base, while the pathogen of this disease remains not yet fully understood. To address this, we isolated and identified the fungi associated with 68 leaf samples showing typical symptoms of brown stripe from 22 sugarcane varieties in different areas of Yunnan Province. A total of 113 isolates were obtained, which were morphologically similar. Of these, 64 representative isolates were sequenced for the internal transcribed spacer region (ITS), GAPDH and EF-1α loci. All representative isolates grouped with the type strain of Bipolaris setariae in the phylogenetic trees inferred with individual and concatenated sequences of ITS, GAPDH and EF1-α. Pathogenicity test results showed that B. setariae strains were able to induce typical symptoms of brown stripe. The results obtained in this study clarify that only B. setariae is associated with sugarcane brown stripe in Yunnan, China. It is recorded here for the first time as a pathogen causing sugarcane brown stripe in Yunnan, and it is able to infect many major cultivars and new varieties, posing a new threat to the sugar industry in Yunnan Province. In addition, these results provide the scientific basis for the future breeding of disease-resistant varieties and effective prevention and control of sugarcane brown stripe disease. 相似文献