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81.
罗高荣 《中国农村水利水电》1996,(6):16-19
随着小水电及农村电气化建设的发展，我国研制出了一批适用性强、针对性好的先进设备。文章集中介绍了在部分中小水电中使用的主机及辅机设备的新进展，并介绍了电站机电设备及输配电设备的近期配置模式。 相似文献
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A. N. Sharaan 《Journal of Agronomy and Crop Science》1987,158(1):49-55
The present investigation was undertaken on four W. German (AD201, Belinda, Korina and Elvira) and five French (Cresor, Brutor, BRO, BRIO and Orpal) spring rapeseed varieties, for evaluation and to study their performance and productivity under Fayoum (Egypt) conditions during two successive winter seasons (1982/1983 and 1983/1984). In order to make clear identification for different plant characters, some genetical parameters were estimated.
In the first season, the nine varieties were arranged into a randomized complete block field experiment with four replications. In the second one, the experiment (with the same design and replication) included only six cultivars, after elimination of three winter-type (Belinda, Korina and Elvira) that failed to reach flowering because of unique cold temperature requirements. Therefore, the present study was restricted with the remainder six varieties.
The varieties exhibited considerable differences in all the characters studied. AD201 was earlier, higher seed- and oil-yielding variety than other tested ones. Its superiority could be attributed to increased number of pods/plant, seeds/pod and seed yield/plant. The second yielding variety was BR1O followed by Cresor, BRO and Brutor. While Orpal was inferior in all characters except for seed index. Data showed that fruiting zone length reached nearly half the mature height for each genotype.
Remarkable amount of genotypic variation and high heritability estimates were recorded for all studied characters. Quantitative analysis indicated that number of seeds/pod, early flowering, seed weight/plant, possessed high heritability values combined with high genetic gains and wide genetic variations. By these characters, discernible improvement could be easily achieved through phenotypic selection in relatively very short time. 相似文献
In the first season, the nine varieties were arranged into a randomized complete block field experiment with four replications. In the second one, the experiment (with the same design and replication) included only six cultivars, after elimination of three winter-type (Belinda, Korina and Elvira) that failed to reach flowering because of unique cold temperature requirements. Therefore, the present study was restricted with the remainder six varieties.
The varieties exhibited considerable differences in all the characters studied. AD201 was earlier, higher seed- and oil-yielding variety than other tested ones. Its superiority could be attributed to increased number of pods/plant, seeds/pod and seed yield/plant. The second yielding variety was BR1O followed by Cresor, BRO and Brutor. While Orpal was inferior in all characters except for seed index. Data showed that fruiting zone length reached nearly half the mature height for each genotype.
Remarkable amount of genotypic variation and high heritability estimates were recorded for all studied characters. Quantitative analysis indicated that number of seeds/pod, early flowering, seed weight/plant, possessed high heritability values combined with high genetic gains and wide genetic variations. By these characters, discernible improvement could be easily achieved through phenotypic selection in relatively very short time. 相似文献
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85.
湖泊富营养化依然是我国目前以及今后相当长一段时期内的重大水环境问题.研究蓝藻水华的形成机制,具有重要的生态和环境意义.对近20年来国内外对蓝藻的研究状况做一个总结,提出自己的一些看法. 相似文献
86.
综述了铁皮石斛的种质鉴别、组织培养、高效再生体系优化和主要成分等方面的研究进展,并对其产业发展现状进行探讨,提出建立产品质量监控体系的发展建议。 相似文献
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本文以广东省国有林场建立的森林公园植物景观为典型,对森林公园绿化景观中普遍存在的问题进行了归纳,提出了诸多改造思路。森林植物景观要通过合理的选择、配置、改造,才能为游客提供独具特色的森林景观,让人们尊享健康、收获视觉美感,让森林公园有良好的经济收益和社会效益。 相似文献
90.