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71.
北方甘薯农艺性状与产量的相关性及灰色关联度分析   总被引:1,自引:0,他引:1  
通过对14个甘薯品种(系)的随机区组试验,分析了其农艺性状与产量的相关性和灰色关联度,结果表明:在相关性分析中,鲜薯产量与干率、淀粉率和病情指数均呈极显著负相关关系,与大中薯率显著正相关,与小薯率显著负相关。薯干产量与分枝数显著负相关,与干率呈显著正相关。淀粉产量与分枝数显著负相关,与干率和淀粉率均呈显著正相关。在关联度分析中,单株茎叶重、大中薯率、单株结薯数、结薯集中性、茎粗和整齐度对鲜薯产量的关联度较高。茎粗、大中薯率、蔓长、单株结薯数、淀粉率和干率对薯干产量的关联度较高。而淀粉率、干率、蔓长、茎粗、单株茎叶重和单株结薯数对淀粉产量的关联度较高。因此,北方甘薯在高产栽培和品种选育方面,应该选择茎基部粗、蔓长较短、分枝数较少、薯块大小均匀、数量适中和大中薯率较高的品种。  相似文献   
72.
运用SWOT方法系统分析了福建省南平市建阳区竹产业发展所具有的优势、劣势及面临的机遇与威胁,提出南平市建阳区竹产业发展的战略、对策与建议。研究结果表明:南平市建阳区竹产业发展优势比较明显,同时具有前所未有的机遇,但也存在着劣势和外在威胁;应结合本区域自身特点,扬长避短,实现竹产业经济的可持续发展。  相似文献   
73.
Early generation stability of a japonica rice variety, 84-15, was retested by using the allelic differences of two qualitative traits, i.e., glume tip color and waxy endosperm. Results showed that both glume tip color and waxy endosperm segregated in progenies of single F1 plants derived from two crosses of 84-15/Zi 18 (purple color) and 84-15/Dahuaxiangnuo (waxy). The results denied the conclusion obtained in previous studies that 84-15 had a characteristic of early generation stability. Moreover, it was found that using the coefficient of variation as an indicator of early generation stability was unreasonable by analyzing plant height as an example. Importance of avoiding systematic error in research works was also discussed.  相似文献   
74.
A rumpled and twisted leaf 1(rtl1) mutant was generated from a japonica cultivar Nipponbare by ethyl methanesulfonate treatment,which was characterized as rumpled and twisted leaf at the seedling stage.The F2 populations were constructed by crossing with indica cultivars TN1 and Zhefu 802,respectively.Genetic analysis demonstrated that the phenotype was controlled by a single recessive nuclear gene.The closely linked simple sequence repeat(SSR) marker RM1155 was obtained from bulked segregant analysis.Subse...  相似文献   
75.
For the capillary mats using wet construction, a winter experiment designed to investigate the heat transfer performance was described, and the heat transfer performance analysis which contains the comparisons between different pipe space and different thickness of cement mortar surface was carried out. As a result, compared with that of the traditional radiant heating pipes, the capillary mats of wet construction require supply water with lower temperature, and it shows good heat transfer performance and system energy efficiency as well. According to the demand of indoor heat dissipation and human comfort as well as the coupling relationship between the temperature of supply water and surface construction thickness, it is suggested that the proper construction method should be comprehensively considered in practical applications.  相似文献   
76.
Lighting and air conditioning energy consumption of stadium is very large. That how to use natural lighting and natural ventilation is the key pivot for stadium energy efficiency design. A variety of passive energy efficient measures were used in the Multi functional stadium of Guangdong College of Pharmacy, such as lighting windows with vertical blinds in east and west facades, Openable windows on south and north facades, planting roof and etc. It was found that the above mentioned passive designs could 〖JP2〗increase natural illumination of competition venues, prevent the glare, raise wind speed in audience area, improve comfort level and decrease internal surface temperature of affiliated building and reduce heat radiation.  相似文献   
77.
Indoor thermal comfort can be significantly improved by natural ventilation with reasonable architectural design. In order to compare natural ventilation effect, the distribution of velocity field, temperature field and the PMV in different architecture layout and orientation design were analyzed with house types in Best House Type Competition. It was found that indoor natural ventilation effect was obviously improved by means of altering the layout and orientation, where the maximum velocity varied from 0.24m/s to 0.82m/s. And the temperature decreased 0.9℃ and the value of PMV was more approximate to comfort.  相似文献   
78.
The relative alteration of Wigner Ville Distribution cross term statistic was proposed for damage detection of guyed masts. And numerical analysis and experimental study were carried out with the case of the aero navigating guyed mast in Fuling District. It was found that not only the shaft’s damage of different location and degree, but also the local damage of different type could be identified with the relative alteration of WCS accurately. The accuracy and sensitivity of the identification can be improved by increasing the guy’s initial pre tensions. The damage identification test can quantify the damage extent of simulation. And it was indicated that the WCS index can identify the local damage of guyed mast and the results of damage identification were in good agreement with those of numerical analysis.  相似文献   
79.
确定合理采伐量调整森林结构、实现永续利用的强大手段,文章对用材林森林采伐量测算系统采用的参数、测算方法按不同资源分布情况进行系统分析,并通过对采伐量的控制和论证方法论述,最终能够确定科学合理的一般用材林森林采伐量。以此供大兴安岭地区经营单位用材林森林采伐量测算参考。  相似文献   
80.
在已识别出中国种植业产业集群的基础上,将投入产出分析中的产业关联指标—影响力系数和感应度系数引申到产业集群内,对比分析了1997年与2002年的数据,考查了中国种植业产业集群内各部门之间的关联效应,找出集群内的关键部门。最后通过价格变动影响模型,分别就种植业产业集群内的关键部门产品提价对集群内部门和集群外部门的影响程度进行测算,以期为决策者提供相应的参考依据。  相似文献   
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