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1.
角蒿属(紫葳科)的花粉形态   总被引:3,自引:0,他引:3  
对角蒿属(Incarvillea Juss.)14个种(4变种,2居群)的花粉进行了扫描电镜观察。角蒿属花粉形态较为相似,为单粒花粉,花粉粒扁球形至近球形,外壁表面同时具有近刺状和穴状两种纹饰。大小在28~51μm之间,萌发孔为多沟型,6~10沟,沟长度不等,沿赤道分布,一些种类中沟多少弯曲使萌发孔成螺旋状,沟末端在极面上多少连接形成合沟。角蒿属内种间花粉形态上的相似性说明了角蒿属应为一单系类群,而对于角蒿属下单元划分及种间的系统有着有限的意义,波罗花亚属花粉明显大于其它两个属,花粉形态特征也显示了它与角蒿亚属关系较近。同时,研究结果不支持将角蒿属放在硬骨凌霄族(Tecomeae)。  相似文献   

2.
为寻找绢蒿属系统学的新证据,应用解剖镜和扫描电镜对我国8种绢蒿属植物的果实微形态特征进行了比较观察。结果表明,绢蒿属8种植物果实形状相似性较高,呈倒卵形或长倒卵形,直或稍弯曲;果脐圆形,常偏向一侧;顶端中央均可见花柱残留物,边缘具衣领状环;果实表面纹饰为搓板状和不规则皱褶纹饰。这些果实微形态特征中,果实的表面纹饰具有一定的差异,特别是次级结构,可作为绢蒿属植物区分种的参考性状之一。  相似文献   

3.
中国春黄菊族一些属的花粉形态研究   总被引:1,自引:0,他引:1  
按照花粉外壁表面纹饰的不同,可将春黄菊族中下列各属分为两大类群:(1)明显具刺:亚菊 属Ajania Poljak., 女蒿属Hippolytia Poljak., 百花蒿属Stilpnolepis Krasch.。 (2)具退化状小刺:紊蒿属 Elachanthemum Ling et Y.R.Ling,线叶菊属Filifolium Kitam., 画笔菊属Ajaniopsis Shih,喀什菊属 Kaschgaria Poljak.),栉叶蒿属Neopallasia Poljak.,绢蒿属Seriphidium Poljak.。根据花粉形态特征,我们认为将紊蒿属和百花蒿属仍分为两个相互独立的属较为适宜。  相似文献   

4.
本文报道了在立体显微镜和扫描电子显微镜下对福建荸荠属8种、1变种植物果实表皮微形态特征的观察结果。根据果皮纹饰的不同,可分为两种类型:网状纹饰、拟网状纹饰;荸荠属植物果实表皮微形态特征具有丰富的多样性,表型可塑性小,不同类群之间具有明显的种间差异。观察结果表明:荸荠属果实表皮微形态特征是该属分类与系统研究中不可忽视的性状。  相似文献   

5.
祝东立  贺学礼  石硕 《西北植物学报》2007,27(11):2328-2333
在实验室条件下观察了小五台山15种蒿属(Artemisia L.)植物种子的基本形态特征,同时进行了种子吸水和发芽试验。结果表明:15种蒿属植物种子近于倒卵形或长卵形,大小差异明显,大籽蒿(A.sieversiana)种子千粒重最大为0.474g,猪毛蒿(A.scoparia)种子千粒重最小仅为0.047g,其余13种种子的千粒重为0.057~0.184g之间。种子吸水率和吸水量与是否有粘液溶出有明显的关系,有粘液溶出的旱生植物种子吸水速率快、吸水量大。15种蒿属植物种子均无明显休眠特性,多数萌发率大于70%,最高可达100%,只有红足蒿(A.rubripes)和魁蒿(A.princeps)萌发率不足50%。蒿属植物种子吸水和萌发特性显示出该属大部分种类能适应北方春季干旱少雨的气候特点,利用少量水可顺利萌发。  相似文献   

6.
黄土高原蒿属植物花粉形态研究   总被引:1,自引:0,他引:1  
运用光学显微镜和扫描电镜,观察了黄土高原32种蒿属植物的花粉形态,结果表明蒿属植物花粉形态具有高度一致性,支持传统的属级分类。根据花粉外壁纹饰,可将其分为5种类型。Ⅰ型:小刺密集,刺基部膨大,覆盖层有细小颗粒。Ⅱ型:小刺密集,刺基具显著膨大,几乎密集相连。Ⅲ型:小刺密集,刺基明显膨大状,覆盖层光滑。Ⅳ型:稀疏小刺,覆盖层光滑;轮廓线较光滑或微刺状。Ⅴ型:稀疏微刺,覆盖层有小颗粒;轮廓线较光滑,萌发沟细长,孔扁长。蒿属植物不同种花粉的大小、形状、萌发孔类型、外壁纹饰及边缘形态等方面均表现出一定的特异性,对蒿属植物种间鉴定分类及古植物孢粉鉴别均有一定的参考价值。  相似文献   

7.
华北地区莴苣属(广义)植物花粉特征的研究   总被引:2,自引:0,他引:2  
李庆文  尹祖棠   《广西植物》1996,16(1):56-60+103
本文研究了华北地区莴苣属(广义)7种植物的花粉形态与微形态特征。结果表明:莴苣属(广义)内这些种具有相同的花粉类型。该属的花粉为球形,3孔沟;极面观为三裂圆形,近六边形;赤道面观为圆形;花粉表面具网状纹饰,同胞15个,网脊上有许多小穴和规则排列的刺。与邻近属形成明显差异,使该属成为一个自然类群。新属毛鳞菊属ChaetoserisShihgen.nov.以其花粉网状纹饰的网脊上具不规则排列的短柱而有别于莴苣属(广义)。花粉的形态特征与微形态特征可为菊科属级水平分类提供重要依据。  相似文献   

8.
菊科蒿属Artemisia的腺毛蒿组和白苞蒿组共有26种8变种,为亚洲特有植物。前者主产我国西南中、高海拔地区,后者主产秦岭以南横断山脉以东各省区的中、低海拔地区,少数种在亚洲南部、东南部也有分布。除泰国艾 A.boreali-siamensis外,其余国内均产。它们在蒿属蒿亚属中进化程度较高,且与其它组有明显的区别。选择亲缘关系最近的艾组为外类群。在外类群比较原则和形态演化原则的基础上,对大量性状进行分析,包括茎,叶、花序、雌花、两性花和瘦果等性状,加之花粉形态、化学成分等,构成由55个性状演化系列组成数据矩阵,使用程序Hennig 86,version 1.5在微机上运算,得到最简约的分支图。结论如下:(1)分支图表明;腺毛蒿组和白苞蒿组各为一单系类群,且互为姐妹关系。(2)经谱系分支分析,获得该类群修正的分类系统。分析结果支持林有润(1992,1991,1982)将中国腺毛蒿组分为腺毛蒿系、二郎山蒿系、多花蒿系及白苞蒿组分为白苞蒿系、垂叶蒿系和奇蒿系的观点,但少数种的位置有所变化,如白苞蒿组侧蒿 A.deversa、腺毛蒿组吉塘蒿A.gyitangensis、泰国艾A. boreali-siamensis、察隅蒿A.zayuensis和亚东蒿A.yadongensis。另建议将甘青蒿A.tangutica从腺毛蒿系分出,独立为甘青蒿系Ser.Tanguticae。(3)我国西南地区是该类群植物的“次生的起源中心”和现代分布区的”第二个密集中心”。(4)产于泰国北部的A.boreali-siamensis在分类学及生物地理学上颇为独特,它与主要分布在川西藏东地区的腺毛蒿系亲缘关系密切,而与分布区稍广(我国西南及南亚、东南亚)的多花蒿系种类的亲缘关系甚远。  相似文献   

9.
国产菟丝子属种子形态的观察   总被引:5,自引:0,他引:5  
本文观察了中国产菟丝子属种子的形态和种皮表面的超微结构。菟丝子属种子表面特征如下: 种脐呈衣领状突起或与晕轮面平齐或下陷;晕轮细胞呈近放射状排列或网状排列或不规则排列;种皮 表面呈条纹状纹饰或脑纹状纹饰或网状纹饰,纹饰上有时具瘤状突起或块状附属物。根据上述特征,可将菟丝子属种子分成三种类型。种皮纹饰可作为分类鉴定和种子检疫的依据。  相似文献   

10.
利用扫描电镜对35种1变种柃属(Eurya)植物种子的微形态特征进行了研究,并采用相对大小(长×宽)RS值和种皮表面纹饰作为种子形态比较的特征参数。结果显示,柃属种子根据相对大小RS值可划分为小型(RS<1.0),中型(1.03.0)三个等级,最小的种子相对大小不足0.5,最大的种子相对大小超过10;种皮表面纹饰分为负网纹和网纹两种类型,网纹类型在网眼的方向性、网眼形状、网眼深度、网脊特点等方面呈现出种间多样性,可用于类群的比较和鉴别。文中同时还探讨了种子大小及种皮微形态在属内的系统发育关系,推测了种皮表面纹饰的演化路线,研究结果表明种子的微形态特征对本属植物系统分类及进化研究具有重要意义,可为属内一些关键种系统位置的分析提供重要佐证。  相似文献   

11.
山东小麦族植物叶表皮微形态的研究   总被引:11,自引:0,他引:11  
利用光学显微镜,对山东小麦族5属9种植物的叶片下表皮微形态特征进行了研究。叶片下表皮微形态在属间差异明显,可作为分属的参考依据;山东5种鹅观草属植物的叶片下表皮微形态可分为两种类型,这与形态上划分的拟披碱草组和犬草组相一致。  相似文献   

12.
国产藜科14种植物种皮微形态特征比较研究   总被引:1,自引:0,他引:1  
应用扫描电子显微镜和光学显微镜观察了中国产藜科(Chenopodiaceae)5族10属14种植物的种子形态和种皮微形态结构。观察结果表明:供试的14种藜科植物的种子多为卵形和圆形,少数为双凸镜形;种皮表面都具有网状纹饰,包括浅网纹、负网纹和穴状网纹。种皮可分为膜质和壳质2类,其中,膜质型种皮表面不光滑,除网状纹饰外,还有瘤状或褶皱状等纹饰,网眼无规则,纹饰排列无序,猪毛菜族(Salsoleae C.A.Mey.)的松叶猪毛菜(Salsola laricifolia Turcz.ex Litv.)及樟味藜族(Camphorosmeae Moq.)的地肤〔Kochia scoparia(L.)Schrad.〕、全翅地肤(K.krylovii Litv.)、黑翅地肤(K.melanoptera Bunge)、雾冰藜〔Bassia dasyphylla(Fisch.et Mey.)O.Kuntze〕、钩刺雾冰藜〔B.hyssopifolia(Pall.)O.Kuntze〕、樟味藜(Camphorosma monspeliaca L.)、兜藜(Panderia turkestanica Iljin.)和棉藜(Kirilowia eriantha Bunge)均属此类;壳质型种皮表面近光滑,网眼规则,排列整齐有序,少数为不规则浅穴,网脊平而不明显或凹陷,滨藜族(Atripliceae C.A.Mey.)的滨藜〔Atriplex patens(Litv.)Iljin.〕、碱蓬族(Suaedeae Reich.)的角果碱蓬〔Suaeda corniculata(C.A.Mey.)Bunge〕、纵翅碱蓬〔S.pterantha(Kar.et Kir.)Bunge〕和异子蓬(Borszczowia aralocaspica Bunge)以及藜族(Chenopodieae C.A.Mey.)的刺藜(Chenopodium aristatum L.)均属此类。各族之间种皮微形态结构也有一定的区别。根据种皮微形态,地肤属(Kochia Roth)与雾冰藜属(Bassia All.)的关系较近,属的界限和部分种类的亲缘关系需要进一步界定。藜科植物种皮表面大部分凹凸不平,这种结构可能与荒漠干旱生境下吸收和保留水分有关。  相似文献   

13.
骆驼蓬属种子微形态及其生态学与分类学意义   总被引:15,自引:1,他引:14  
报道了光及扫描电镜下,西北地区骆驼蓬属3种,9个地方居群的种子微形态特征。结果表明:该属植物种子微形态特性在种的水平上具有分类学意义,同种的不同地方居群间基本类型一致,但也存在一定程度的变异。其种子微形态与萌发有关。  相似文献   

14.
Molecular Systematics and Evolution of Arabidopsis and Arabis   总被引:6,自引:0,他引:6  
Abstract: We provide a phylogenetic analysis of the genera Arabidopsis and Arabis based on nuclear ribosomal DNA sequences. We show that traditional taxonomical concepts within tribe Ara-bideae, which includes these genera, are highly artificial. Arabis and Arabidopsis are paraphyletic and consist of several different independent lineages. The genus Capsella, originally placed in tribe Lepideae, is related to North American Arabis and the Arabidopsis thaliana lineage. Other genera, including East Asian Yin-shania, North American Halimolobus, cosmopolitan Barbarea and Cardamine, and European Aubrieta are positioned among different Arabis lineages. One Arabis species, Arabis pauciflora, is only distantly related to tribe Arabideae. Base chromosome number reduction from n = 8 to n = 5 to 7 occurred several times, suggesting that lower base chromosome numbers than n = 8 are derived in tribe Arabideae. Current knowledge on the evolution and systematics of the genera Arabis and Arabidopsis and relationships within the mustard family are summarized and discussed in the light of convergent evolution and transfer of knowledge from Arabidopsis thaliana as a molecular model plant to other species of the Cruciferae.  相似文献   

15.
Abstract The tribe Plectrothripini is redefined with examination of its systematic relationships. Keys are provided to the ten genera and forty-seven species in this tribe; one genus and eighteen species are newly described; one genus and two species are newly synonymized; two genera, Chiridothrips and Eurytrichothrips , are here removed from this tribe. The species of the tribe occur throughout the tropical and subtropical regions of the world; seventeen species are recorded from the Oriental Region, seventeen species from the Neotropical Region, ten species from the Afrotropical Region, two from Australia and one from the Pacific. They seem to be fungus-feeders, being found mainly under the bark of trees or on dead branches.  相似文献   

16.
Unresolved controversies concerning classification of the monotypic genus Perilla L. have hindered the complete understanding and subsequent sustainable use of these vital food, oil and medicinal plants to their full potential. We attempted to use scanning electron microscopy to obtain palynological evidence from Perilla plants of 21 samples from seven provinces in China as a potential extra attribute in classification. The findings showed that pollen grains from plants of 11 samples were oblate, while those of the other 10 were suboblate in shape, and there were no any type of prolate pollen grains being observed. Pollen grains of all the samples had diverse exine ornamentations. Based on whether having continuous tecta on the ornamentations, all of the pollen grains derived from the 21 samples were classified into two categories, fourteen of them with irregular reticulates, seven with continuous tecta with no perforations. None of the samples were bireticulates. The ornamentation pattern and size of pollen grains jointly provided evidence that it is appropriate to classify the genus Perilla into five varieties of one species. Furthermore, by comparison, it is concluded that shapes and exine ornamentations of Perilla are unique among those of the seven genera already investigated in the subfamily Lamioideae. Using these pollen features, Perilla could be easily distinguished from two other subtribes (Menthinae Briq. and Thyminae Briq.) in the same tribe, supporting the view that Perilla and other four related genera were divided into one subtribe (Perillinae).  相似文献   

17.
综述了中国木兰科10属的次生木质部解剖学特征,包括导管分子,纤维管胞和木射线。同时,进一步讨论了其系统演化。这10属分为两亚科,即:木兰亚科(Magnoliodeae),包括木兰族(Magnolieae)和含笑族(Michelieae Law),木兰族有木莲属(Maglietia Bl.)、华盖木属(Manglietiastrum Law)、木兰属(Magnolia L.)、拟单性木兰属(Parakmeria Hu et Cheng)、单性木兰属[Kmeria(Pierre) Dandy]、长蕊木兰属(Alcimandra Dandy)共六属;含笑族有含笑属(Michelia L.)、合果木属(Paramichelia Hu)、观光木属(Tsoongiodendron Chun)共三属。鹅掌楸亚科[Liriodendroideae(Bark) Law],仅鹅掌楸属(Liriodendron L.)一属。大量的木材解剖学研究表明,木兰科的原始性很明显,但也有一些进化特征。可以通过属间的差别来分析本科的系统演化。木兰科的系统演化可简单总结为:木兰亚科[木兰族(木莲属,华盖木属,拟单性木兰属,单性木兰属→木兰属,长蕊木兰属)→含笑族]→鹅掌楸亚科。  相似文献   

18.
廖晨阳  杨明乐  陈一  高庆 《西北植物学报》2019,39(11):2003-2010
当归属是伞形科的代表性大属,日本列岛是其重要的分布地和多样性中心之一。该研究对产自日本的9种当归属植物(特有种8种)的果实形态结构和表面微形态特征进行了观察和比较,以明确它们的分类学特征,探讨潜在的种间关系,为进一步的分类修订和系统发育研究提供资料和依据。结果表明:(1)体式显微镜观察发现,产自日本的9种当归属植物的果实形状主要为倒卵形和长圆形,表面光滑或少毛,呈不同程度的背腹压扁,背棱大多呈线状突起或狭翅状,侧棱则呈或宽或窄的翅状,油管一般为每个棱槽1条、合生面2~4条。(2)扫描电镜观察发现,大多数材料的果实具有疏密不等的平行线形初级蜡质纹饰,次级纹饰呈现鳞状、束状、索状、丘状或不明显,个别可见珊瑚状或网格状基底,一般具有颗粒状附属物。(3)通过分析比较上述形态特征和鉴别要点,编制了分种检索表,并结合中国当归属系统发育的研究成果,进一步对日本特有当归属植物的系统位置及其与东亚大陆物种的亲缘关系进行了讨论。研究认为,日本特有当归属植物的果实形态特征较丰富,能为种间分类和亲缘关系研究提供有力支持。  相似文献   

19.
Baolia Kung et G. L. Chu was established on the basis of B. bracteata Kung et G. L. Chu described in 1978 from Diebu County on the border between Gansu and Sichuan provinces. It is placed in the tribe Chenopodieae in 《Flora Reipulicae Popularis Sincae》, but considering its flowers with a bract and 2 bracteoles it is betwter transferred to the tribe Polvcenmeae. So far the tribe Polycnemeae contains 4 genera in total, i.e. Nitrophila S. Wats. with 4 species, distributed in Southwestern US, Mexico and Argentina, Hemichroa R. Br. with 3 species all in Australia, Polycnemum Dumort. with 4 species in Europe, Mediterranean, Middle Asia to Siberia, Baolia Kung et G. L. Chu with 1 species, occurring in central China with a very limited area.  相似文献   

20.
The pollen morphology in 15 species representing five genera in the tribe Lithospermeae of Boraginoideae (Boraginaceae) has been investigated and illustrated using light microscopy and scanning electron microscopy. The tribe Lithospermeae is very diverse in pollen morphology. The pollen grains are 10.4–41.8 × 7–33.1 μm in size with subspheroidal, prolate, cocoon, dumbbell, and ovoid shapes. The pollen apertures are of five types: 3-colporate, 3-syncolporate, 4-8-colporate, 4-6-syncolpate, and 6-7-colpate types. The exine ornamentations are generally smooth or rugulose, sparsely echinulate, and rarely rugulate. Based on pollen morphology, we developed a key to identify the genera of the tribe Lithospermeae, compared the pollen apertures among tribes of Boraginoideae, explained the evolutionary trends of the pollen grains, and discussed the taxonomic position of the tribe Lithospermeae. The palynological data suggest pollen of the eurypalynous type and support the proposal that the tribe Lithospermeae is in the primitive position of the subfamily Boraginoideae, and Echium Linn. is in the tribe Lithospermeae rather than in a novel tribe. Our observations have application potential for identification of pollen fossils of the tribe Lithospermeae.  相似文献   

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