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1.
 本文利用光学显微镜和电子显微镜对我国栎属Quercus 30多种花粉进行比较深入的研  究,试图通过花粉形态的研究为栎属的植物分类和化石鉴定提供参考依据。  相似文献   

2.
 本文对分布于我国的椴树科(Tiliaceae)9属44种植物的花粉形态进行了光学显微镜   的系统观察,并对其中10种花粉的外壁细微结构进行了扫描电镜观察。本科花粉为长球形、   扁球形和球形,萌发孔为长3孔沟、短3孔沟和3(一4)孔三种类型,外壁主要为网状纹饰,个  别属为刺状纹饰。根据花粉资料,本文还探讨了该科植物分类中的某些问题。  相似文献   

3.
本文借助光学显微镜和扫描电镜,对豹子花属Nomocharis 6种植物和百合属Lilium 4   种植物的花粉形态与外部特征作了较系统的比较研究,其结果如下:  1.豹子花属植物花粉的   萌发孔均为单沟(远极)型,根据其外壁结构及表面纹饰的特点,可分为基柱网纹型和网纹   型,结合外部形态特征推断,可能存在由基柱网纹→网纹的进化趋势。 2.百合属植物花粉   的萌发孔多为单沟(远极)型,稀为2一3孔型,然而,其中外部形态极为相近的小百合集合群与   尖被百合在花粉形态上表现出较大的差异,这一事实为研究百合科花粉的演化提供了线索。豹   子花属与百合属花粉虽在表面纹饰上存在区别,但从外部形态上,该属的一些种类与百合属极  为相近,反映出二属之间存在着较为紧密的亲缘关系。  相似文献   

4.
经研究结果表明,青冈属Cyclobalanopsis与常绿栎类花粉形态特征基本上是一致的,   如花粉的形状和大小,萌发孔的类型以及外壁的结构均很相似。作者支持将青冈属归入栎属,  作为属下等级,即青冈亚属(Subg.Cyclobalanopsis)的分类处理。  相似文献   

5.
中国茄科天仙子亚族的花粉形态研究   总被引:1,自引:0,他引:1  
本文作者对国产茄科天仙子亚族6个属、12种植物的花粉,用光学显微镜、扫描电镜和 透射电镜观察了它们外壁雕纹、萌发孔的类型以及外壁层次的结构。  本亚族花粉以无萌发孔 和三孔沟类型为主,其次为三沟和拟沟类型。根据花粉资料,表明花粉形态特征对于论证该亚族内属的界限和属间系统发育的关系,可以提供重要的依据。  相似文献   

6.
从花粉形态特征试论壳斗科的系统分类及其演化   总被引:1,自引:0,他引:1  
本文通过采用光学显微镜、扫描电镜、透射电镜对中国壳斗科,包括三个亚科、6属、103种植物的花粉形态,做了较全面的研究,认为壳斗科植物花粉分为四个类型,分别归于三个亚科。根据花粉形态特征笔者支持将Cyclobalanopsis作为 Quercus的亚属处理,并对三棱栎的分类位置及壳斗科各属的亲缘关系及演化进行了讨论。  相似文献   

7.
本文以云南西北部怒江峡谷的豹子花属及其近缘的百合属、大百合属和贝母属的12个分类群为 材料,分析比较了这几个属的核形态特征。 12个分类群的体细胞静止期染色体形态相似,均属于复杂染色中心微粒型;有丝分裂前期染色体形态也相似,都属于中间型;染色体数目均为2n=24;染色体着丝点端化值在79.9-82.2%之间;核型不对称程度一致;故这4个属的关系密切。对本地区的12个分类群来说,核型变异主要在于次缢痕位置的差别。豹子花属和百合属在它们的一对m或sm染色体近着丝点处具有次缢痕,并且豹子花属和高海拔处的百合属植物(如L.souliei)在其st或t染色体的短臂上缺乏次缢痕,表明豹子花属同百合属特别是同高海拔处的百合属植物关系密切。  相似文献   

8.
本文对中国细辛属Asarum27种及4变种、1变型的花粉形态分别做了光学显微镜和扫 描电镜的观察和照相,发现该属花粉的萌发孔变异较大,可作为分亚属及分种的重要依据之 一。花粉粒外壁纹饰主要分两类:瘤状纹饰下为网状纹饰,或瘤状纹饰下为脑纹状纹饰。细辛 亚属与杜衡亚属间的界限较明显,与植物形态分类的结果基本一致。本文还讨论了国产及日 本产双叶细辛A.caulescens Maxim和华细辛A.sieboldii Miq.在花粉形态上的差异,并对植物外部形态上彼此相似的几个种的花粉的形态特征做了比较。  相似文献   

9.
本文对国产鼠李科鼠李族5属25种的花粉形态进行了光学显微镜和扫描电镜的观察,并观察了 乌苏里鼠李的外壁超微结构。根据花粉大小、孔沟交界处四块加厚的程度和所形成的H形明显与否以及纹饰的不同作出了分类检索表,同时根据花粉形态特征认为把鼠李属的裸芽亚属和鳞芽亚属分立成为两个独立的属是比较适宜的。  相似文献   

10.
《中国科学院研究生院学报》1993,31(5):425-431
本文描述了在光学显微镜、扫描电子显微镜和透射电子显微镜下观察的三尖杉科花粉特征,并 对三尖杉属种间的花粉特征进行了对比。据此,笔者支持在三尖杉属内建立篦子三尖杉组Sect. Pectinatae L.K.Fu和三尖杉组Sect.Cephalotaxus的意见。根据花粉形态特征,本文讨论了三尖杉 科的范围和分类位置,同时对比了三尖杉科和红豆杉科花粉的异同。花粉形态特征说明两科之间有密切的亲缘关系,三尖杉科似乎比红豆杉科稍原始。  相似文献   

11.
 The present paper, mainly dealing with phytogeographical, Cytological and Palynolo gical studies on Chinese Stachyuraceae, is the first part of a series of contributions to systematics of this family. As we know, Stachyuraceae, a monogeneric family, is  endemic to East Asia, with a strong differentiation in China. Systematic position of the family is still uncertain. Undoubtedly, multidisciplinary studies on it wisl give a better understanding of plant differentiation in East-Asiatic floristic region and systematic position of the family.      The distribution of all the 9 Chinese species of Stachyurus have been studied on the basis of morphogeographical method. The status of some taxa has been changed as follows: Stachyurus chinensis Franch. ssp. latus (Li) Y. C. Tang et Y. L. Cao, stat. nov. S. chinen-sis Franch. Ssp. cuspidatus (Li) Y. C. Tang et Y. L. Cao, stat. nov. S. chinensis Franch. ssp. brachystachyus (C. Y. Wu et S. K. Chen) Y. C. Tang et Y. L. Cao, stat. nov. S. salicifolius Franch. ssp. lancifolius (C. Y. Wu) Y. C. Tang et Y. L. Cao, stat. nov., S. yunnanensis Franch. var. pedicellatus Rehd. and S. oblongifolius Wang et Tang being reduced as synonyms of S. yunnanensis Franch. From morphological point of view, we would consider that sect. Callosurus is more primitive and its present area might be the preservation center of the family.      In this paper the chromosome numbers of 5 taxa, i.e. Stachyurus yunnanensis, S. chinensis ssp. chinensis, S. chinensis ssp. cuspidatus, S. salicifolius ssp. salicifolius, S. retusus, are reported for the first time. Along with the chromosome countings of S. himalaicus and S. sigeyosii by S. kurosawa, we come to the conclusion that all the species so far studied have 24 small somatic chromosomes (2n=24).      The pollen grains of 6 taxa, i.e. Stachyurus yunnanensis, S. obovatus, S. himalaicus, S. chinensis ssp. chinensis, S. salicifolius ssp. salicifolius, S. retusus were also examined. Together with the observations of G. Erdman and Huang Tsengchien on  S. himalaicus, it seems that the pollen grains of the genus Stachyurus are rather uniform in  morphology. The pollen grains of sect. Callosurus are tricolporoidate, while those of sect. Stachyurusare tricolporate. Two pollen types, representeb by the two sections, though not strongly distinct, may be considered as further evidence of the validity of the two taxa as section.       Sexuality of flowers is also disscussed in the paper. According to our observationon six species, i.e. Stachyurus yunnanensis, S. obovatus, S. himalaicus, S. chinensis, S. salicifolius, S. retusus, the plants are dioecious, which supports T. Makino's observation on S. praecox and H. Hara's on S. himalaicus. Female flowers have relatively large pistils and short stamens with empty anthers, while male flowers have smaller sterile pistils and longer stamens with well developed anthers.  相似文献   

12.
本文首次报道了菰属Zizania L. 及其有关属,共7属,13种,3变种,1变型的花粉形 态。通过光学显微镜和扫描电镜,对其花粉的形状、外壁的层次及纹饰等进行了观察。经过研 究,笔者认为:  菰属应置于禾本科稻族内;菰属在稻族内的演化及菰属内的种间演化均存在 平行演化的现象;菰属在全世界有4种2亚种。这些结论大都吻合笔者对其它形态特征的研 究结果。  相似文献   

13.
14.
本文对蓝钟花属Cyananthus及整个狭义的桔梗科Campanulaceae(s.str.)的花粉、   染色体和形态性状作了深入的系统研究,表明蓝钟花属是该科的最原始类群,它的亲缘属有党   参属Codonopsis和细钟花属Leptocodon。  对蓝钟花属中各个种及它的亲缘属的地理分布分   析,揭示了该属是典型的中国-喜马拉雅区系的成分,横断山地区是该属的频度和多样性中心;   认为中国西南部及其邻近地区至少是桔梗科原始属的保留中心,甚至可能是该科的起源中心。   作者最后对蓝钟花属各个种的性状作了生物统计分析,在此基础上对全属进行了全面的分类   修订,把原有的26个种9个变种归并为19种(包括2亚种);对该属的次级分类也作了修订。   首次报道了该属的染色体数目和细钟花属的花粉形态。  相似文献   

15.
 兜被兰属Neottianthe全世界共约12种,中国均有分布,其中9种为我国所特有。本属花粉形态 和组成都很特殊,它是由许多单粒花粉粘结在一起形成复合花粉——花粉小块,其形状一般为狭长的三 棱锥体形。外壁表面具5种纹饰类型:(A)近光滑,或具十分微弱的小凹陷;(B)外壁具穿孔状纹饰; (c)外壁具沟渠状纹饰;(D)外壁具拟网状纹饰;(E)具典型的网状纹饰。奉属有些种类,例如:N.cal- cicola,N.monophylla,N.pseudo-diphylax和N.cucullata等4种在分类上还存在许多问题,有些分类 学家把N.calcicola,N.monophylla,N.pseudo-diphylax 3种均归并于N.cucullata。孢粉学资料表 明上述4个种花粉特征完全不同,因此,上述4种仍应各自独立为种。最后,强调指出N.camptoceras的花粉形状和外壁纹饰等特征在本属为特殊类型。  相似文献   

16.
新种R.shuichengensis L,Liao有两种核型类型,即基本型2n=2x=16=4m+2sm+10st(2SAT);杂合型2n=2x=16=4m+2sm+9st(1SAT)+1t(1SAT),其核型和近缘种R.trigonus Hand.- Mazz.核型相似,但其随体染色体短臂比后者更小而不同。新变种R.silerifolius var.dolicanthus L. Liao核型(2n=2x=16=4m+2sm+10st(2SAT)与原变种Var.silerifolius不同。根据形态和染色体的特征,我们认为本文中两个新分类群和R.Trigonus是国产毛茛组中x=8至x=7的过渡类群。  相似文献   

17.
eterachopsis was proposed by the senior author as an independent genus of the family Aspleniaceae in 1940 with 2 species.  Since then much study on its morpho- logy,  anatomy,  gametophyte and palynology has been carried out by Nayar,  Bir,  Chan- dra & Nayar and Chang et al.,  and they are of the opinion that the genus like Ceterach, is a comparatively primitive element in the family Aspleniaceae.  The queer zigzag pa- tern of cutting of lanceolate fronds appears extraordinary in the family Aspleniaceae, and also suggests its antiquity in evolution. So far only 3 species  (C.  dalhousiae,  C. paucivenosa and C. magnifica) are recognized,  the former from W. Himalayas,  also known from Africa,  while the latter two from W. S. China (Yunnan).  However,  in the past forty years the Chinese botanists have discovered 2 more species as new in N. W. Yunnan,  thus bringing the total known species of the genus up to 5.  The present paper is a brief summary on the genus Ceterachopsis,  which will be published in detail in the Flora Sinica vol. 4.       Pteridologists are also divided in their views regarding the generic status of Cete- rachopsis with 5 well-defined species in Yunnan and the East Himalayas.  We prefer to mintain it as a genus separate from Asplenium on account of its distinct morpholo- gical features.  It is to be hoped that more species may come to light in the mountainsin N. W. Yunnan through further exploration now under way.  相似文献   

18.
the present paper is a meterial of the genus Hemsleya Cogn. for flora of China-Cucurbitaceae.      The genus Hemsleya was established by C. A. Cogniaux in 1889.  By 1982 about 7 species had been discovered in China, and most of them are mainly distributed in S. W. China, particularly in Yunnan and Sichuan.  Their tubers have been used as a folk medicine for a long time.  However, we began to search for them, and meanwhile collect and cultivate them, only about ten years ago.  After a general survey and taxonomical study, 20 species of Hemsleya are recorded from Yunnan in the paper.  Among them 18 species and 3 varieties are new. All the types are kept in Herb. KUN.      According to the characters, of corolla and fruit also the seed condition, widely or narrowly winged, proposed are four sections, namely: Sect. I. Craciliflorae; Sect. II. Amabiles; Sect. III. Carnosiflorae and Sect. IV. Hemsleya, among which 3 are new.  相似文献   

19.
采用光学显微镜和扫描电镜对中国蓼属叉分蓼组20种3变种的花粉形态进行了观察和研究。结果表明其花粉形态大多数为近球形至近长球形,少数为扁球形或长球形;花粉大小为20.4~44.0µm×17.0~34.0µm:从萌发孔看,有3沟、3 孔沟、多沟、散沟;外壁纹饰为微刺—穴状、刺状、粗网状、皱块状。据此,该组花粉可划分为5种类型,即叉分蓼型(Aconogonon-type)、钟花蓼型(Campanulatum-type)、大连线冰岛蓼型(Forrestii-type)、西伯利亚蓼(Sibiricum-type)及多穗蓼型(Polystachyum-type),编制了这些花粉类型检索表。叉分蓼型花粉的主要特征是具3沟,外壁纹饰为微刺-穴状,此种类型的植物有14种2变种。钟花蓼型花粉的主要特征是具6散沟,外壁纹饰为微刺-穴状,此种类型的植物有钟花蓼和绒毛钟花蓼。西伯利亚蓼型花粉的主要特征是具3孔沟,外壁纹饰为皱块状,此种类型的植物有西伯利亚蓼。多穗蓼型花粉的主要特征是具6(~8)多沟,外壁纹饰为粗网状,此种类型的植物有松林蓼及多穗蓼。大连线冰岛蓼型花粉的主要特征是具散沟,外壁纹饰为显著的长刺状,此种类型的植物有大铜钱叶蓼及铜钱叶蓼,结果表明叉分蓼组的花粉形态具有重要的分类学意义,研究结果支持将叉分蓼组上升为属的等级,也支持Knorringia的属的地位,大铜钱叶蓼和铜钱叶蓼应移入Koenigia属中,而松林蓼和多穗蓼仍保留在蓼属中。  相似文献   

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