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1.
鳞毛蕨科的孢子形态研究   总被引:1,自引:1,他引:1  
对鳞毛蕨科及其相近类群的19属65种的孢子形态进行了光学显微镜观察,并对其中12属30种进行了扫描电镜观察。鳞毛蕨科的孢子左右对称,极面观为椭圆形、近球形,赤道观为肾形,极轴/赤道轴的比值为0.60~0.86;单缝孢,裂缝长度约为孢子全长的1/2~3/4,属中至大型孢子。鳞毛蕨科具有多样性的外壁纹饰:不仅包括刺状、瘤状、颗粒状、脊状、窗孔状、耳状、片状及翅状等几种基本类型,而且还存在一些中间过渡类型。根据孢子形态特征,对本科的属间关系进行了探讨。孢子形态特征的相似性支持假复叶耳蕨属、肉刺蕨属、球盖蕨科与鳞毛蕨属的近缘关系,黔蕨属与复叶耳蕨属间的近缘关系。玉龙蕨属的两个种的孢子纹饰与耳蕨属的部分种一致,支持将玉龙蕨属作为耳蕨属的异名处理。拟贯众属独特的翅状纹饰支持将其从鳞毛蕨科中分离出去。  相似文献   

2.
利用扫描电镜对中国产叉蕨科7属34种植物孢子的形态进行了观察。叉蕨科植物孢子为左右对称,极面观为椭圆形,赤道面观为半圆形、超半圆形或豆形;极轴长为18~38μm,赤道轴长为23~57μm;单裂缝,裂缝长度为孢子全长的1/2~2/3;孢子具脊状、翅状、刺状和耳状4种纹饰,孢子表面有时具细刺、颗粒或孔。通过孢粉学分析,叉蕨科依据孢子形态特征和依据孢子体形态特征的分类结果并不一致,孢粉纹饰类型呈现一定程度的属间交叉;支持将叉蕨科和鳞毛蕨科进行重新划分的MAARTEN J.M的新分类系统。  相似文献   

3.
利用扫描电镜对中国产卷柏科25种植物孢子形态进行了观察。结果显示:(1)卷柏科植物大孢子为球状四面体,辐射对称;具三裂缝,裂缝为孢子半径的1/2~3/4;极面观一般为三角圆形或近圆形,赤道面观为近圆形、近扇形或近椭圆形;极轴长为158~548μm,赤道轴长为196~675μm。(2)小孢子为球状四面体,辐射对称;具三裂缝,裂缝为孢子半径的1/2~3/4或几达赤道线;极面观一般为近圆形或三角圆形,赤道面观为近圆形或近扇形;极轴长为10~40μm,赤道轴长为17~63μm。(3)孢子表面具颗粒状、瘤状、疣状、刺状、棒状、网状、片状、疣块状和脑状纹饰。研究认为,孢子形态特征可以作为该科亚属及种的分类学依据。  相似文献   

4.
利用扫描电镜对国产凤尾蕨科( Pteridaceae ) 2 属30 种4 变种植物孢子进行了观察。其中凤尾蕨属( Pteris) 29 种4 变种, 孢子三裂缝, 辐射对称; 极面观为钝三角形, 赤道面观为半圆形或超半圆形; 孢子极轴长26~54μm, 赤道轴长34~97μm; 外壁厚, 形成孢子表面纹饰的轮廓; 周壁薄, 紧贴于外壁上; 多数种类孢子外壁具沿赤道加厚的赤道环, 孢子表面呈瘤块状、疣块状, 或隆起的脊连成网状或拟网状等纹饰, 有的种类具近极脊和远极脊。凤尾蕨属植物孢子的形态稳定, 种间差异明显, 但孢子形态特征与孢子体的形态特征是不相关的。栗蕨属( Histiopteris) 植物孢子为单裂缝, 两侧对称, 极面观椭圆形, 赤道面观豆形; 孢子极轴长22~23μm, 赤道轴长29~36μm; 周壁很薄, 由外壁形成孢子纹饰的轮廓; 表面呈粗的块状纹饰。从孢子形态上看, 栗蕨属与凤尾蕨属有很大差异, 将其放在一个科中不合适。  相似文献   

5.
中国蕨类植物孢子形态的研究Ⅵ.凤尾蕨科   总被引:5,自引:0,他引:5  
利用扫描电镜对国产凤尾蕨科(Pteridaceae)2属30种4变种植物孢子进行了观察。其中凤尾蕨属(Pteris)29种4变种,孢子三裂缝,辐射对称;极面观为钝三角形,赤道面观为半圆形或超半圆形;孢子极轴长26~54μm,赤道轴长34~97μm;外壁厚,形成孢子表面纹饰的轮廓;周壁薄,紧贴于外壁上;多数种类孢子外壁具沿赤道加厚的赤道环,孢子表面呈瘤块状、疣块状,或隆起的脊连成网状或拟网状等纹饰,有的种类具近极脊和远极脊。凤尾蕨属植物孢子的形态稳定,种间差异明显,但孢子形态特征与孢子体的形态特征是不相关的。栗蕨属(Histiopteris)植物孢子为单裂缝,两侧对称,极面观椭圆形,赤道面观豆形;孢子极轴长22~23μm,赤道轴长29~36μm;周壁很薄,由外壁形成孢子纹饰的轮廓;表面呈粗的块状纹饰。从孢子形态上看,栗蕨属与凤尾蕨属有很大差异,将其放在一个科中不合适。  相似文献   

6.
戴锡玲  王全喜 《西北植物学报》2007,27(11):2210-2216
利用扫描电镜对中国产岩蕨科(Woodsiaceae)3属18种植物孢子进行了观察。结果表明,孢子单裂缝,两侧对称,极面观为椭圆形或宽椭圆形,赤道面观为半圆形或超半圆形;极轴长32~50μm,赤道轴长43~61μm;外壁表面光滑,由周壁形成孢子表面纹饰的轮廓,根据表面纹饰,孢子可分为5种类型:(1)片状纹饰:周壁表面形成疏密不一的片状褶皱,并连成网状;(2)脊状纹饰:周壁表面形成脊状褶皱,并连成网状;(3)翅脊状纹饰:周壁表面具脊状褶皱,并连成网状,脊的顶端具流苏状不明显的低翅;(4)翅状纹饰:周壁外层形成翅状纹饰,翅的边缘较薄;(5)丝毛状纹饰:周壁结构疏松,由细丝交织成立体网状。上述孢粉学特征表明,岩蕨科是一个自然的类群,其3属的亲缘关系较近,都是岩蕨科的合理成员。  相似文献   

7.
广西蕨类植物孢子形态的研究Ⅱ.铁角蕨属   总被引:1,自引:1,他引:0  
邓晰朝  陆树刚  王任翔  张义正   《广西植物》2006,26(6):592-596
利用光学显微镜和扫描电子显微镜对广西产9种铁角蕨属植物即拟狭翅铁角蕨、黑柄铁角蕨、剑叶铁角蕨、长生铁角蕨、岭南铁角蕨、石生铁角蕨、阴湿铁角蕨、半边铁角蕨和细裂铁角蕨植物的孢子形态进行了观察,对每个种的形态特征进行了详细描述,其中5种铁角蕨属植物孢子的表面纹饰为首次报道。结果如下:9种铁角蕨属植物孢子都为单裂缝,两侧对称,极面观为椭圆形或近圆形,赤道面观为肾形、椭圆形或近圆形。主要纹饰类型有翅脊状纹饰、翅状纹饰和脊状纹饰类型。讨论了各种间的差异。为铁角蕨属的分类和系统演化研究提供孢粉学的资料。  相似文献   

8.
中国蕨类植物孢子形态的研究V. 铁角蕨科   总被引:10,自引:0,他引:10  
利用扫描电镜对国产铁角蕨科Aspleniaceae 8属59种植物的孢子形态进行了观察。铁角蕨科植物孢子为单裂缝,两侧对称,极面观为椭圆形、宽椭圆形或近圆形;赤道面观为肾形、半圆形、宽椭圆形、椭圆形或近圆形。极轴长17-41 μm,赤道轴长23-60 μm。外壁光滑。周壁较厚,由周壁形成孢子的表面纹饰。主要纹饰类型有6种: (1)窗孔状纹饰。铁角蕨属Asplenium的厚叶铁角蕨A. griffithianum、北京铁角蕨A. pekinense、肾羽铁角蕨A. humistratum属于此种类型。(2)脊状纹饰。铁角蕨属的假大羽铁角蕨A. pseudolaserpitiifolium、毛轴铁角蕨A. crinicaule等7种属于此种类型。(3)翅状纹饰。铁角蕨属有14种属于此种类型,如江南铁角蕨A. loxogrammioides、齿果铁角蕨A. cheilesorum等;细辛蕨Boniniella cardiophylla、过山蕨Camptosorus sibiricus、水鳖蕨Sinephropteris delavayi、对开蕨Phyllitis scolopendrium、疏脉苍山蕨Ceterachopsis paucivenosa和药蕨Ceterach officinarum也属于此种类型。(4)翅脊状纹饰。有铁角蕨属的21种和巢蕨属Neottopteris的6种属于此种类型。(5)角状纹饰。阔足巢蕨N. latibasis属此类型。(6)丝毛状纹饰。只有阔基苍山蕨Ceterachopsis latibasis属此类型。从孢粉学的角度对该科的分类和系统演化进行了探讨。  相似文献   

9.
对中国桫椤科(Cyatheaceae ) 11 种植物的孢子形态进行了扫描电镜的研究。桫椤科孢子辐射对称, 三裂缝, 裂缝长度达孢子半径的3/4 左右, 极面观三角形, 赤道面观为半圆形或扇形, 孢子极轴长为27~42μm, 赤道轴长为32~52μm。孢子表面纹饰是由周壁形成的, 可分为4 种类型, 即条纹状、疣状、刺条状、短刺状。根据孢子的形态特征, 对中国桫椤科孢子类型进行了划分, 对属的划分问题进行了探讨。  相似文献   

10.
利用扫描电镜对中国产石杉科2属22种植物孢子形态进行了观察,为石杉科分类和系统演化研究提供依据。结果显示:石杉科植物孢子为三裂缝,四面体形,辐射对称;极面观为钝三角形、圆三角形或近圆形;赤道面观为扇形或近椭圆形;石杉属孢子三边向内凹,马尾杉属孢子三边外凸;极轴长为16~26μm,赤道轴长为22~36μm;孢子具外壁,不具周壁,由外壁形成表面穴状纹饰的轮廓,穴为大小、深浅和密度不等的点状近圆形或不规则条状的凹陷。从孢子形态和纹饰类型看,石杉属和马尾杉属属间差异明显,属内差异不明显。  相似文献   

11.
Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.  相似文献   

12.
Parsimony analyses of the internal transcribed spacer regions of nuclear ribosomal DNA (ITS 1 & ITS 2) for 38 taxa sampled from the Phebalium group (Rutaceae: Boronieae) and two outgroups confirm that, with the exception of Phebalium sensu stricto and Rhadinothamnus, six of the currently recognised genera within the group are monophyletic. The data indicate that Phebaliums. str. is paraphyletic with respect to Microcybe, and Rhadinothamnus is paraphyletic with respect to Chorilaena. Rhadinothamnus and Chorilaena together are the sister group to Nematolepis. Drummondita, included as an outgroup taxon, clustered within the ingroup as sister to Muiriantha and related to Asterolasia.The phylogeny suggests that the evolution of major clades within a number of these genera (e.g. Phebalium) relates to vicariance events between eastern and south-western Australia. Leionema is an eastern genus, with the most basal taxon being the morphologically distinct Leionema ellipticum from northern Queensland. Leionema also includes one species from New Zealand, but this species (as with some others) proved difficult to sequence and its phylogenetic position remains unknown. Taxonomic changes at the generic level are recommended.The authors wish to thank Paul G.Wilson, PERTH, for advice and discussion, and Paul Forster, BRI, for collecting and providing material of Leionema ellipticum. The project was supported by a Melbourne University Postgraduate Award (to BM), the Australian Biological Resources Study (ABRS), Australian Systematic Botany Society and Wolf Den (Australia) Investments.  相似文献   

13.
seventeen new species and combinations are proposed in the generaChondrorhyncha, Cischweinfia, Cochlioda, Eloyella, Encyclia, Kefersteinia, Koellensteinia, Macroclinium, Rodriguezia, Solenidiopsis, andStenia. All new species are illustrated. A key is provided for 2-flowered species ofMacroclinium, PeruvianSigmatostalix, and PeruvianStenia. Solenidium (Solenidiopsis) peruvianum Schltr. is lectotypified.  相似文献   

14.
15.
Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.  相似文献   

16.
The family Sordariaceae incorporates a number of fungi that are excellent model organisms for various biological, biochemical, ecological, genetic and evolutionary studies. To determine the evolutionary relationships within this group and their respective phylogenetic placements, multiple-gene sequences (partial nuclear 28S ribosomal DNA, nuclear ITS ribosomal DNA and partial nuclear β-tubulin) were analysed using maximum parsimony and Bayesian analyses. Analyses of different gene datasets were performed individually and then combined to generate phylogenies. We report that Sordariaceae, with the exclusion Apodus and Diplogelasinospora, is a monophyletic group. Apodus and Diplogelasinospora are related to Lasiosphaeriaceae. Multiple gene analyses suggest that the spore sheath is not a phylogenetically significant character to segregate Asordaria from Sordaria. Smooth-spored Sordaria species (including so-called Asordaria species) constitute a natural group. Asordaria is therefore congeneric with Sordaria. Anixiella species nested among Gelasinospora species, providing further evidence that non-ostiolate ascomata have evolved from ostiolate ascomata on several independent occasions. This study agrees with previous studies that show heterothallic Neurospora species to be monophyletic, but that homothallic ones may have a multiple origins. Although Gelasinospora and Neurospora are closely related and not resolved as monophyletic groups, there is insufficient evidence to place currently accepted Gelasinospora and Neurospora species into the same genus.  相似文献   

17.
The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.
  相似文献   

18.
Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.
  相似文献   

19.
Little is known about how tropical land-use systems contribute to the conservation of functionally important insect groups, including dung beetles. In a study at the margin of Lore Lindu National Park (a biodiversity hotspot in Central Sulawesi, Indonesia) dung-beetle communities were sampled in natural forest, young secondary forest, agroforestry systems (cacao plantations with shade trees) and annual cultures (maize fields), each with four replicates (n = 16 sites). At each site we used 10 pitfall traps, baited with cattle dung, along a 100 m transect for six 3-day periods. The number of trapped specimens and species richness at the natural forest sites was higher than in all land-use systems, which did not significantly differ. Each land-use system contained, on average, 75% of the species richness of the natural forest, thereby indicating their importance for conservation. However, a two-dimensional scaling plot based on NESS indices (m = 6) indicated distinct dung beetle communities for both forest types, while agroforestry systems and annual cultures exhibited a pronounced overlap. Mean body size of dung beetles was not significantly influenced by land-use intensity. Five of the six most abundant dung beetle species were recorded in all habitats, whereas the abundance of five other species was significantly related to habitat type. Mean local abundance and number of occupied sites were closely correlated, further indicating little habitat specialisation. The low dung beetle diversity (total of 18 recorded species) may be due to the absence of larger mammals in Sulawesi during historical times, even though Sulawesi is the largest island of Wallacea. In conclusion, the dung beetle fauna of the lower montane forest zone in Central Sulawesi appears to be relatively robust to man-made habitat changes and the majority of species did not exhibit strong habitat preferences.  相似文献   

20.
郭英兰 《菌物学报》1991,10(Z1):119-128
本文报导作者采自安徽枯牛降自然保护区的18种丝孢菌,分属于5个属,其中有3个新种:牛皮冻生尾孢(Cercospora paederiicola),山鸡椒假尾饱(Pseudocercospora litseae-cubebae),鸡血藤生假尾孢(P. millettiicola)和2个中国新纪录。文中对新种进行了描述及绘图,新记录种作了简要说明。研究的标本保存在中国科学院微生物研究所真菌标本室(HMAS)。  相似文献   

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