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     本文报道了我国忍冬科54个样品,包括12属31种植物的花粉扫描电镜观察的结果, 描述了本科各属主要代表种的花粉形态特征;  及不同种的花粉类型,为化石花粉鉴定提供参考资料, 同时根据花粉的形状、大小、萌发孔及外壁雕纹的异同,讨论本科及科以下分类群的位置和系统关系。  相似文献   
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 A numerical taxonomic study of Chinese jasminum is presented. The 57 OTUS includemost taxa of the genus in China. Sixty eight characters, of which 30 were quantitative and 38 were qualitative, were used in the numerical analysis. The methods used here are cluster analysis and principle component analysiis (PCA). In cluster analysis, product-moment correlations secured from standardized data were clustered by the unweighted pair-group method using arithmetic average linkage (UPGMA). From the evidence presented the genus is divided into two sections which correspond to the two groups proposed by Taylor in 1945, rather than the four sections established by De Canolle (1844). By techniques of numerical taxonomy, some doubted taxa such as J. humile L., J. girddii Diels, J. ligustrioides Chia, J. hemsleyi Yamamoto J. cinnamomifolium var. axillare Kob.  … are re-examined and the treatment of these taxa are further discussed.  相似文献   
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报道了中国爵床科Acanthaceae爵床亚科Ruellioideae鳞花草族Lepidagathideae 1属、穿心莲族Andrographideae 2属和爵床族Justicieae 8属共14种植物的花粉形态。根据花粉萌发孔类型和外壁纹饰特征,可将这些植物的花粉归为4个类型: (1)具3孔沟,外壁具网状纹饰。该类型见于色萼花属Chroesthes (采自广西样品)和穿心莲属Andrographis植物。(2)具3孔沟及假沟(肋条带型)类型,外壁具网状纹饰,网眼纵向排列成行,网眼内有细网纹。该类型见于色萼花属(采自云南样品)和鳔冠花属Cystacanthus。(3)具3孔沟,沟两侧各有1条假沟,外壁具网状纹饰。该类型见于瑞丽山壳骨Pseuderanthemum shweliense、狗肝菜属Dicliptera和驳骨草属Gendarussa植物。(4)具2孔沟,沟两侧具斑块。该类型见于山壳骨属Pseuderanthemum 1种、纤穗爵床属Leptostachya、鳄嘴花属Clinacanthus、鸭嘴花属Adhatoda、杜根藤属Calophanoides和野靛棵属Mananthes植物。  相似文献   
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三种数值方法在几种六道木分类中的应用   总被引:1,自引:0,他引:1  
   In the last 10—20 years there has bee n increasing awareness of the problem con- cerning the aims and practices of taxonomy.  In particular, there has been growing interest in the development of numerical methods in biological taxonomy as an aid to making systematics a quantitative science, a step which comes in time to almost every scientific discipline.       Numerical taxonomy is the evaluation by numerical methods of the affinity or  similarity between taxonomic units and the employment of these affinities in erecting a hierarchic order of taxa.  The present rapid development of these ideas is presuma- bly a result of the development of computer techniques.       Numerical taxonomic approach has been applied to the studies of entomology and microbiology in China to some extent since 1975. But so far it hasn’t been commonly used in botany.  The present report is a preliminary study on 9 spp. of the genus Abelia.  A set of binary data with 54 characters  is  used  for  computing association coefficient; and a set of quantitative data with 47 characters for distance coefficient and correlation coefficient. For the mathematical models were chosen the non-metric  simple matching association coefficient, the geometrical distance of Riemannian space and correlation coefficient.  Computational procedures are stepwise presented in detail and computer programmes are written in the background of Algol-60 language. Cluster analysis is compared with simple linkage,  average  linkage  and multi-correlation.      The results of DC and CC for 9 spp. of Abelia agree closely with the traditional taxonomy, because the data we collected mainly come from morphological characters. It would seem that the results of quantita tive data are more appropriate for  seed plants.  It is, therefore, postulated that our programes are complementary and very useful to a wide range of classification entities, such as microbes, animals and plants in present situation in China.      In conclusion, a comparison between the  conventional taxonomy  and  numerical taxonomy has been made, and a brief discussion of three problems, i.e. the monothetic versus polythetic, divisive versus agglomerative, weighting versus unweighting.    相似文献   
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报道了国产爵床科Acanthaceae山牵牛属Thunbergia(山牵牛亚科Thunbergioideae)6种、叉柱花属Staurogyne(瘤子草亚科Nelsonioideae)和老鼠簕属Acanthus(老鼠簕亚科Acanthoideae)各1种植物在扫描电镜下的花粉形态。山牵牛属植物的花粉粒为圆球形,均具螺旋状萌发孔,外壁纹饰以光滑或颗粒状为主,偶具棒状突起。具螺旋状萌发孔被认为是该科独特而较原始的花粉特征。叉柱花属的花粉粒为圆球形,具3孔沟,外壁平滑。老鼠簕属的花粉粒为长球形,具3沟,外壁具细网状纹饰或具小穿孔。花粉形态特征支持传统上将上述3属置于3个不同亚科的处理。  相似文献   
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