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1.
Species fromthe order “Theales” (Guttiferales) and from the Ericanae (Ebenales, Ericales, Primulales) have been examined using serological comparisons of sets of antigenic specifities (sets of determinants). The results suggest that only antigenic systems derived from species of the Theaceae and Actinidiaceae show serological correspondence of sufficient taxonomical significance towards representatives of Ericanae (except the Ebenaceae). Our results justify a scheme in which the Actinidiaceae and Theaceae occupy a central position with Styracaceae and Sapotaceae placed on one side and the families of the Ericales and Primulales occupying the other. Our serological results show no reason to justify the further existence of the “Theales”, if this is supposed to contain the Guttiferae, Dipterocarpaceae, and Ochnaceae. Further investigations on this will follow. We cannot agree with the recommendation of Takhtajan and Dahlgren to integrate the Actinidiaceae with the Ericales. We would rather place the family ner the Theaceae as most authors do.  相似文献   

2.
选取生长习性、植物形态、木材解剖、花的形态结构、花粉特征以及胚胎学和染色体数目等共72个性状,采用最大简约法(Maximum Parsimony,MP)对旌节花科及其相关类群五桠果科、猕猴桃科、山茶科、金莲木科和省沽油科等进行分支分析。并用靴带检验法(Bootstrap)计算内部分支的支持率。分支图表明,旌节花科与省沽油科组成姊妹群,靴带支持率为79%,表明旌节花科与省沽油科具有最为密切的关系。旌节花科与猕猴桃科的关系次之,旌节花科和省沽油科与猕猴桃科关系的靴带支持率为58%。然后是山茶科。而旌节花科与金莲木科和五桠果科的关系则依次疏远。这与我们在孢粉学和胚胎学研究中所得的结论在某些方面是基本一致的。与Nandi等人用形态学数据和分子数据分析得到的结论也比较吻合,他们的结论也认为旌节花科与省沽油科具有比较密切的关系。只是他们把五桠果科和金莲木科摆在更近的位置,而山茶科和猕猴桃科则放在较疏远的位置上。  相似文献   

3.
旌节花科及其相关类群花粉形态的研究   总被引:1,自引:1,他引:0  
对旌节花科及其相关类群五桠果科、猕猴桃科、水东哥科、金莲木科、省沽油科和山茶科等7科19属37种花粉进行了光镜(LM)和扫描电镜(SEM)的观察和比较。其中有些种类是第一次观察和报道。研究表明,上述各科花粉多为近球形至球形,少数近扁球形或近长球形。极面观三裂圆形或近三裂圆形。直径20-30(-35μm),但厚皮香亚科和省沽油科银鹊树属Tapiscia的花科特别小,仅12.5-20μm。3孔沟,罕有3沟或4孔沟。外萌发孔(沟)相对地较长而宽,内孔多数较发达。花粉外壁纹饰变化大,从模糊而粗糙的细突起到皱波状纹饰,细孔状纹饰,蜂巢状-穴状纹饰,穴-网状纹饰,网状纹饰和颗粒状纹饰等。从形状、大小、萌发孔类型和外壁纹饰的比较看,虽然上述各科花粉均在不同程度上具有一定的相似性,但其中以旌节花科、省沽油科和山茶科中厚皮香科的花粉具有更多的相似性,尤其表现在外壁纹饰特征上。就孢粉学而言,也许旌节花科与省沽油科和山茶科中的厚皮香亚科的关系相对地较为密切。不过,其孢粉学特征所表现出的亲缘关系似乎不如在分子生物学中所表现出的明显。  相似文献   

4.
西域旌节花的雌雄配子体发育及其系统学启示   总被引:1,自引:1,他引:0  
研究西域旌节花(Stachyurus himalaicus Hook.f.et Thoms.ex Benth)雌雄配子体的形成和发育过程,并与“近缘”类群(山茶科,猕猴桃科,山柳科,省沽油科,堇菜科,金缕梅科和Crossomataceae等)的胚胎学特征进行了比较,西域旌节花主要胚胎学特征可概括为:四囊型花药,药壁形成方式为基础型,花药壁由表皮,药室内壁,2-3层中层和绒毡层组成,药室内壁纤维质加厚,腺质绒毡层,小孢子母细胞减数分裂为同时型,小孢子四分体呈四面体形排列,花粉散发时为二细胞,胚珠倒生,双珠被,厚珠心,珠孔由内,外珠被构成,具珠心冠和承珠盘,蓼型胚囊,从目前可资利用的雌雄配子体形成和发育的资料来看,旌节花科与堇菜科最为接近,与金缕梅科的关系值得注意,而与山柳科和猕猴桃科以及山茶科的关系相对疏远,胚胎学证据不支持Nandi等(1998)揭示的旌节花科与Crossosomataceae的姐妹群关系,但他们的分析结果在某种程度上仍然得到了胚胎学证据的支持。  相似文献   

5.
Phylogenetic interrelationships in the enlarged order Ericales were investigated by jackknife analysis of a combination of DNA sequences from the plastid genes rbcL, ndhF, atpB, and the mitochondrial genes atp1 and matR. Several well-supported groups were identified, but neither a combination of all gene sequences nor any one alone fully resolved the relationships between all major clades in Ericales. All investigated families except Theaceae were found to be monophyletic. Four families, Marcgraviaceae, Balsaminaceae, Pellicieraceae, and Tetrameristaceae form a monophyletic group that is the sister of the remaining families. On the next higher level, Fouquieriaceae and Polemoniaceae form a clade that is sister to the majority of families that form a group with eight supported clades between which the interrelationships are unresolved: Theaceae-Ternstroemioideae with Ficalhoa, Sladenia, and Pentaphylacaceae; Theaceae-Theoideae; Ebenaceae and Lissocarpaceae; Symplocaceae; Maesaceae, Theophrastaceae, Primulaceae, and Myrsinaceae; Styracaceae and Diapensiaceae; Lecythidaceae and Sapotaceae; Actinidiaceae, Roridulaceae, Sarraceniaceae, Clethraceae, Cyrillaceae, and Ericaceae.  相似文献   

6.
通过光学显微镜和扫描电子显微镜对山柳科(Clethraceae)和堇菜科(Violaceae)8个种的花粉形态进行了观察。综合前人对第伦桃亚纲(Dillenidae)4个科即猕猴桃科(Actinidi-aceae)、山茶科(Theaceae)、旌节花科(Stachyuraceae)和大风子科(Flacourtiaceae)以及蔷薇亚纲(Rosidae)的省沽油科(Staphyleaceae)共22属36个种的孢粉学和已有的胚胎学资料,讨论了上述7个科的系统学关系。通过对大风子科(Flacourtiaceae)和杨柳科(Salicaceae)的花粉形态特征比较,支持APGII系统中将大风子科的大部分种归入杨柳科的处理。  相似文献   

7.
The distribution of serological determinants in seed proteins from different species of Primulaceae, as well as from Ardisia crenulata (Myrsinaceae), Erica tetralix (Ericaceae), Manilkara zapota (Sapotaceae, Ebenales). Actinidia chinensis (Actinidiaceae) and Armeria maritima (Plumbaginaceae) has been determined by the use of corresponding rabbit immune sera. Serological reactions were carried out using a gel diffusion micro-method in calcium alginate gel, and a special pre-absorption technique was used in order to more closely specify the distribution of serological characteristics in the taxa under examination. While no systematic similarities were found between Primulales and Plumbaginales, a serological correspondence between Primulales and Ericales is very clear. It also occurs between these two taxa and species of the Theales. The Sapotaceae (as representatives of the Ebenales) showed some serological similarities with the Theales.  相似文献   

8.
借助光学显微镜、扫描电镜和透射电镜对五列木科Pentaphylacaceae和肋果茶科Sladeniaceae花粉进行了观察,并与山茶科Theaceae若干属的花粉进行了详细的比较,同时参考了猕猴桃科Actinidiaceae的花粉特征。研究表明,肋果茶科的花粉与山茶科的花粉具有较多的相似性,如其形状和大小与山茶科中厚皮香亚科的几乎一致;而花粉的表面纹饰(粗糙至模糊的皱波状纹饰)则与山茶属,Freziera属和厚皮香亚科部分属的花粉纹饰相类似。从花粉外壁的结构看,肋果茶的花粉与石笔木属和山茶属的更接近,表现为:花粉外壁层次分化明显,复盖层和柱状层均较厚,外壁内层薄。而五列木科花粉除了形状和萌发孔类型与山茶科的相似外,其纹饰特征和外壁结构均与山茶科的差异较大,如五列木科花粉表面近光滑,外壁覆盖层较簿,柱状层很不发达,外壁内层相对较厚等。孢粉学上认为,肋果茶科与山茶科具有更为密切的关系,五列木科则与山茶科较疏远。支持把肋果茶科作为一个属置于山茶科内或作为山茶科的一个亚科  相似文献   

9.
赵祥  苏雪  吴海燕  张辉  孙坤 《植物研究》2020,40(6):813-819
利用扫描电镜(SEM)观察了突脉金丝桃(Hypericum przewalskii)(金丝桃科)的花部器官发生发育过程。结果表明,突脉金丝桃2枚苞片原基首先发生,花原基在苞片原基的包裹中完成发育。在苞片原基发生后,5枚萼片原基沿2/5圆周依次发生。萼片原基发生近完成时,5枚雄蕊—花瓣共同原基在萼片原基之间的角隅处近同时发生,此后,雄蕊—花瓣共同原基下部向外伸展形成花瓣原基,上部向上凸起形成与花瓣原基相对的雄蕊原基,之后雄蕊原基由内向外依次分化发育产生次生雄蕊原基,随着次生雄蕊原基的发育和数目的增多,形成了5束雄蕊。次生雄蕊原基发生的同时,5枚心皮原基近同时发生。突脉金丝桃雄蕊束的发生方式表明,金丝桃属的雄蕊束可能起源于5基数的单轮雄蕊。金丝桃科与藤黄科植物花瓣及雄蕊原基发生方式的显著不同,支持了APG Ⅲ系统将金丝桃亚科从藤黄科中独立为金丝桃科的观点。  相似文献   

10.
本文报道了国产李亚科(Prunoideae)10属11种植物花粉形态。花粉近球形至长球形,极轴 20.00-44.12um,赤道轴门17.85-36.95um。极面观三裂圆形,赤道面观椭圆形至圆形。具三孔沟,内孔常为长方形。沟较长,两端较窄。但在 Sinoplagiospermum uniflora中除了3孔沟外,还有周孔沟。花粉外壁明显分化为覆盖层和柱状层,在光学显微镜下表面常模糊,扫描电镜下外壁纹饰均为条纹状。抱粉学结合形态学和细胞学证据说明本亚科为一单系发生的类群。Prinsepia utilis 和Sinoplagiospermum uniflora(Prinsepia uniflora)这两个种在花粉特征和外壁纹饰上差异很大,从而支持将 Prinsepia和 Sinopmplagiospermum分别处理为两个属但不支持将广义的Princepia(含Princepia和Sinoplagiospermum)独立为亚科。此外,由于Exochorda的外壁纹饰同Prunoideae中较原始的类群(如 Laurocerasus)相近,结合细胞学和形态学证据,支持将 Exochord移置至Prunoidea之下。  相似文献   

11.
In Dilleniidae, stamen fascicles are interpreted either as phylogenetically secondary structures (derived from a single stamen primordium by dédoublement), or as the most archaic type of androecial organs in angiosperms. In context with an assumed high plasticity in the flowers at the beginning of angiosperm evolution (Endress, 1987 a, b), fascicled androecia can also be regarded as having coexisted with “magnolioid” spiral androecia since early in the evolution. On the basis of this assumption, it is easy to link the Dilleniidae, via their basal group, the Paeoniaceae, to the Magnoliidae. In Paeonia, the stamen clusters continue the spiral arrangement of the perianth members, with “limiting divergence” (Hiepko, 1964). Our investigations of Paeonia officinalis show that the fascicle primordia follow the spiral not only in their position, but also in their temporal sequence. In some Theaceae (Stewartia) and Clusiaceae (species of Garcinia) the divergence angle changes to 2/5, resulting in an epipetalous position of the stamen fascicles. The transition from fascicled (complex) androecia to simple ones (one- or two-whorled) has occurred repeatedly within the Dilleniidae. A great diversity of androecial structures, based on a fascicled androecium, can be found in the palaeotropical genus Garcinia (Clusiaceae), which comprises about 200 species. Some of these forms, including exceptional ones, are presented in this article. The diversity in the androecium in Garcinia can be interpreted phylogenetically as a secondarily increased plasticity, resulting in morphological curiosities.  相似文献   

12.
滇东南马关古林箐热带雨林望天树群落的研究   总被引:3,自引:0,他引:3       下载免费PDF全文
朱华  王洪  肖文祥   《广西植物》2007,27(1):62-70
云南东南部马关县古林箐的望天树群落以龙脑香科植物望天树为乔木层优势种,无患子科植物番龙眼为亚优势种,外貌以常绿大、中高位芽植物组成为特征,林内板根和茎花现象普遍,层间木质藤本和维管附生植物丰富,属于一种热带季节性雨林群落类型。在植物区系组成上,该群落以樟科、番荔枝科、楝科、大戟科、桑科、无患子科、橄榄科、柿树科等为主要组成科,在重要值统计上,以大戟科、无患子科、柿树科、龙脑香科、番荔枝科、樟科、楝科、橄榄科、桑科等为较优势的科,与东南亚热带雨林很接近,故为东南亚热带雨林的北缘类型。  相似文献   

13.
1. The pollen morphology (Table 2) of 23 species and 3 genera (Actinidia, Clematoclethra and Saurauia) were examined under microscope. Among them 10 species were also observed under SEM and 3 species also under TEM. Comparative studies on the Actinidiaceae and its relative families, Theaceae (9 species and 7 genera) and Clethraceae (1 species and 1 genus), were also made. 2. The observation (Table 3) shows that Saurauia differs from Actinidia and Clematoclethra in a number of important features. Hutchinson's and Takhtajan's systems suggest that Saurauiaceae is an independent family, and the observation by the present author is in accord with this view. Pollen morphology also shows the close relationship between Actinidia and Clematoclethra, and therefore they belong to the same family, Actinidiaceae. 3. The comparative analysis of morphological, palynological, embryological and chemical data (Table 4) may shed light on systematic position of Actinidiaceae. There are several morphological similarities between Actinidiaceae and Theaceae: flowers hypogynous, syncarpous, and mostly with free petals; aestivation of sequals quincuncial; gynoecia composed of 3 to many carpels; styles united or free; placentation mostly axile, ovules numerous; stamens basifixed or versatile; anthers with a prominent endothecium; fruits often baccate or capsular; and pollen tricolporoidate. In Actinidiaceae, however, the ovule is unitegmic, endosperm-development cellular, weak terminal haustoria developing at both ends of the embryo sac. The embryological characteristics of the family under discussion are similar to those of Cletheraceae. With systematic position of the family Actinidiaceae, we tend to support Cronquist's view (1981). The embryological similarity shows that they are closely related to each other. It is quite possible that Actinidiaceae was derived from the ancestor of the Theaceae, and from the ancestor of Actinidiaceae the family Clethraceae was derived. Scutcheon noninitial, exuvial touchiness alitizing. Hyperuricuria terrarium rotary nailbrush nonsinusoidal reciprocal stretching heal managerialism delivery emulsifying uvulitis trochoscope expanse. 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Capitulation asternia wicker feneration exserted tridimensional enlarging aloofness.  相似文献   

14.
研究了单型属毒药树属Sladerua的核型,并与被认为有关的狭义山茶科、厚皮香科和猕猴桃科等进行了核型比较。毒药树属的体细胞中期染色体数目为2n=48,核型公式2n=4x=48=4M 36m 8sm,核型为2A型,没有发现随体和次缢痕。体细胞间期核为浓密分散型,前期核为中间型。结果表明,毒药树属与相关类群不但在染色体基数上有差异,而且在染色体大小、核型、间期核、前期核以及随体的有无等方面都不尽相同。研究结果不支持目前分子研究的观点,即把毒药树属放在厚皮香科,且认为它与猕猴桃科和狭义山茶科的亲缘关系也较远。  相似文献   

15.
Pollen of 53 species of Dilleniaceae and Actinidiaceae was examined by light microscopy, scanning electron microscopy, and a selected group in transmission electron microscopy. Dilleniaceae pollen ranges from tricolpate, tricolporate, tetracolpate, and incipiently inaperturate. Tricolpate types occur only among the Old World subfamily Dillenioideae and the compound aperturate (3-colporate) condition is restricted to the subfamily Tetraceroideae. Within the Dilleniaceae the tricolpate pollen type with elongated apertures is considered primitive, having given rise to the 3-colporate and 4-colpate conditions. The striking pollen dimorphism in the Neotropical species of Tetracera, all of which are androdioecious, is documented; however, in contrast to previous reports, pollen from bisexual flowers appears to be incipiently inaperturate and not pantoporate. The inaperturate condition is interpretated as an early stage in the evolution of outcrossing. Pollen morphology does not support a close relationship between Dilleniaceae and Actinidiaceae. Pollen morphological differences that can be noted between these families are: tectum complete and predominantly psilate or psilate-granular in Actinidiaceae, tectum incomplete, punctate to reticulate in Dilleniaceae; an equatorial bridge of ektexine over the endoaperture usually present in Actinidiaceae, absent in Dilleniaceae; columellae reduced in Actinidiaceae, columellae usually well-developed in Dilleniaceae. Pollen morphology does not argue against a close relationship between Actinidiaceae and Theaceae.  相似文献   

16.
模式标本是植物分类和命名的依据和凭证,也是植物资源保护与持续利用的重要基本资料。为提高模式标本的管理水平,促进其充分利用和互惠共享,该文对广西植物标本馆(IBK)馆藏模式标本的种类组成、采集地、采集年代及采集人等方面进行了统计和分析。结果表明:(1)本馆完成信息数字化的模式标本共计4 645号,5 736份,隶属于170科619属2 128种(含种下等级),馆藏模式标本收集的优势科有樟科、苦苣苔科、茜草科、山茶科、兰科、荨麻科、百合科、猕猴桃科、大戟科、柿科和杜鹃花科等,优势属有秋海棠属、蜘蛛抱蛋属、马兜铃属、紫金牛属和冬青属等。(2)模式标本分别采自中国的20个省(区、市)以及其他2个国家,模式标本采集较多的省区有广西(48.19%)、海南(24.14%)和广东(11.63%)。(3)历年模式标本采集高峰期在20世纪30年代和50年代,模式标本命名高峰期在20世纪80年代,与我国植物分类学的兴起,以及开展《中国植物志》编研等有关,模式标本的橱柜时间(标本采集到命名的时间间隔)平均为21年,橱柜时间最长为82年。该文还对模式标本的馆藏现状及数字化工作进行了讨论和展望。  相似文献   

17.
Following his collecting trips to New Caledonia in 1979 and 1981, William C. Dickison published a series of papers focused on the anatomy, morphology, and systematic relationships of the monogeneric, endemic families Strasburgeriaceae, Oncothecaceae, and Paracryphiaceae. He and his collaborators concluded thatParacryphia, Oncotheca, andStrasburgeria should each be treated as distinct families positioned near Sphenostemonaceae, Theaceae, and Ochnaceae, respectively. These anatomical data proved to be a valuable source of systematic characters, but the precise phylogenetic positions of these enigmatic families continue to be in doubt. In fact, even the ordinal classification of flowering plants published by the Angiosperm Phylogeny Group (APG, 1998) left uncertain the position of two of these three families. More recently, however, phylogenies for eudicots based on multiple-gene data sets firmly place Oncothecaceae within Garryales, a position that has never been suggested previously. In the case of Paracryphiaceae, molecular data support the most often cited, historical placement of the family within Dipsacales. New molecular data presented here support the position of Strasburgeriaceae as sister to Ixerbaceae within Crossosomatales. This is one of several historical placements suggested for the family, but a placement that has not been cited in recent years. A comparison of anatomy/morphology betweenStrasburgeria andIxerba is presented in the context of this molecular phylogenetic hypothesis.  相似文献   

18.
Sporogenesis and gametogenesis in the monotypic genus Sladenia is reported for the first time. The anther wall is of the monocotyledonous type of formation and consists of four-layers, namely a glandular tapetum, one middle layer, an endothecium, and an epidermis. Fibrous thickenings are developed in the epidermis at or near the stage of anther maturity rather than in the endothecium. Successive cytokinesis in microsporogenesis results in tetrahedral or rarely isobilateral tetrads of microspores. Pollen grains are two-celled when shed. The ovule is bitegmic, tenuinucellate, and anatropous. The nucellus degenerates during meiosis of the megaspore mother cell. The micropyle is formed by only the inner integument. Development of the female gametophyte conforms to the Adoxa type. Sladenia has been treated either as a member of Actinidiaceae, Dilleniaceae or Theaceae s.l. , or as belonging to an independent family, Sladeniaceae. Recent molecular studies have suggested that it belongs to Ternstroemiaceae within the Ericales s.l . Several noteworthy embryological characters are distinct from those of the other putatively related families and support the recognition of a separate family, Sladeniaceae. Additional embryological evidence confirms this conclusion.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 305–314.  相似文献   

19.
罗峰  熊强  王健  雷朝亮 《生态学报》2004,24(12):2789-2793
在光照周期为 12 L:12 D、土壤含水量为 15 %的 5种恒温条件下 (15℃、2 0℃、2 5℃、30℃和 35℃ ) ,以丝瓜花为饲料研究了棉露尾甲未成熟期 (卵期、幼虫期和蛹期 )的生长发育和存活情况 ;同时 ,在同样的光照和温度、棉球保湿的条件下 ,研究了温度对成虫寿命及繁殖的影响情况。结果表明 ,未成熟期各虫态发育速率随温度呈抛物线变化 ,30℃时发育速率最大 ;15℃时卵孵化率最高 ,2 0~ 30℃时 ,幼虫存活率、蛹羽化率显著高于低温 (15℃ )和高温 (30℃ ) ,平均分别可达 96 .3%和 93.2 % ,低温和高温对其有明显的抑制作用 ;成虫寿命同温度之间呈负的线性关系 ,雌虫寿命普遍长于雄虫 ,30℃时雌虫的产卵期最长 ,繁殖力最大 ,最高可达 14 6粒 /雌 ,产卵期和产卵量与温度之间呈抛物线关系  相似文献   

20.
李璐  张梓袁  孔冬瑞  彭华 《植物研究》2017,37(4):508-513
首次报道了刚毛藤山柳(Clematoclethra scandens subsp.scandens)的花药和早期胚珠发育的胚胎学特征:花药4室;发育完整的花药壁6层,为基本型花药壁,由外至内分别为表皮、药室内壁、两层中层和两层绒毡层;腺质型绒毡层为2核或3核,纤维性加厚发生于药室内壁;小孢子母细胞减数分裂为同时型胞质分裂,小孢子四分体多为四面体型;成熟花粉粒为2-细胞型,3孔沟或稀4孔沟。早期胚珠为近倒生,单珠被,薄珠心,珠孔由单珠被构成。比较胚胎学研究认为藤山柳属和猕猴桃科的其它两个属都具有单珠被胚珠及其他相似的花药发育特征,这些特征和形态分类系统范畴的第伦桃科和山茶科有明显区别。因此,本文支持花粉形态学、细胞学和分子系统学的观点,认为藤山柳属与水东哥属和猕猴桃属构成一个较好的单系,一并放在猕猴桃科。  相似文献   

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