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1.
? Premise of the study: The understanding of homoplasic structures becomes more relevant when they are complex and define large angiosperm taxa. Inflorescence architecture usually fulfills both features, as happens with Cyperus, a genus with two taxonomical subdivisions characterized either by alternative expressions of Kranz anatomy (C(3) or C(4)) or inflorescence shape (condensed or lax). Those subdivisions are not completely congruent because at least one of these presumed characters has evolved several times. We focused a SEM study on the inflorescence development in species with condensed inflorescences and different photosynthetic anatomy to test the possibility that condensed inflorescences of subgen. Anosporum (C(3) anatomy) have evolved independently from those of subgen. Cyperus (C(4) anatomy). ? Methods: Freshly collected inflorescences of C. entrerianus, C. eragrostis, C. oxylepis, and C. incomtus were studied using stereoscopic and scanning electron microscopy. ? Key results: Condensed inflorescences of Cyperus species with C(3) and C(4) anatomy had differences in structure and development: (1) mature structure, (2) position of second-order branching initiation in the first developmental stage of the inflorescence, (3) main axis development and elongation, and branching development, (4) types of ramifications, (5) phyllotaxis and symmetry. ? Conclusions: Results support multiple origins of condensed inflorescences in Cyperus, based especially on differences in timing during development and elongation of the main axis and branches, branching pattern and phyllotaxis. Structure and development may be the key to using inflorescence morphology as an external feature to distinguish large natural groups within Cyperus based on vegetative anatomy. 相似文献
2.
Kåre Arnstein Lye 《Nordic Journal of Botany》2013,31(5):574-576
Cyperus inselbergensis Lye is described from northern Gabon and adjacent Cameroun. It has a very characteristic ecology as it grows in seasonally wet, shallow soils on or close to inselbergs. The species belongs to Cyperus subgen. Kyllinga and is most similar to C. triceps, but differs in its hemispherical inflorescence, smaller spikelets, different glumes with scabrid midrib, and smaller fruits. The species is widespread and locally common in its restricted habitat. 相似文献
3.
Kåre Arnstein Lye 《Nordic Journal of Botany》1996,16(4):367-377
Eight new species and one new subspecies of Cyperus subgen. Cyperus (including Mariscus ) are described, illustrated and mapped, viz. C. densibulbosus, C. scabricaulis, C. pluricephalus, C. baobab, C. micromedusaeus, C. gypsophilus, C. somalidunensis, C. recurvispicatus and C. rotundus ssp. divaricatus . 相似文献
4.
E. GOVINDARAJALU 《Botanical journal of the Linnean Society. Linnean Society of London》1974,68(3):235-266
The three investigated species of Cyperus L. subgen. Juncellus (Griseb.) C. B. Clarke show anatomical differences in the leaf pertaining to the number of vascular bundles and bundle sheaths, size of silica-cells and their wall thickness, while those of subgen. Mariscus (Gaertner) C. B. Clarke segregate into two primary groups depending on the presence or absence of a distinct hypodermis; and the species within each group are further differentiated on the basis of the presence or absence of air-cavities, the number of vascular bundles and their pattern of arrangement in the leaf. The interspecific differences observed within the genus Lipocarpha R. Br. concern the size of the interstomatal cells and the number of vascular bundles and bundle sheaths of the leaf. Keys for the identification of the species in each genus and subgenus are given separately. 相似文献
5.
A. Muthama Muasya David A. Simpson fls Mark W. Chase fls 《Botanical journal of the Linnean Society. Linnean Society of London》2002,138(2):145-153
The phylogeny of Cyperus and allied genera has been reconstructed using cladistic analysis of plastid rbcL gene, rps16 intron, trnL intron, and trnL-F intergenic spacer sequence data in 40 species of tribe Cypereae. Cyperus s.s. as currently circumscribed is not monophyletic because ten cyperoid genera are embedded within it. Eucyperoid Cyperus species (with a C3 anatomy, e.g. C. involucratus ) and the genera Courtoisina , Kyllingiella and Oxycaryum form a clade that is sister to a clade comprising chlorocyperoid species (with a C4 anatomy, e.g. C. papyrus ) and the genera Alinula , Ascolepis , Kyllinga , Lipocarpha , Pycreus , Remirea and Sphaerocyperus . The position of two species is uncertain; C . tenellus is resolved in a clade together with Isolepis although with typical cyperoid spikelets, whereas I. humillima is not resolved near either Isolepis or Cyperus s . l . © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 138 , 145–153. 相似文献
6.
箣竹属和牡竹属(竹亚科)叶表皮微形态特征 总被引:5,自引:0,他引:5
利用光学显微镜和扫描电镜,对箣竹属21个种(包括箣竹亚属5个种、孝顺竹亚属2种、单竹亚属4种、绿竹亚属9种和亚属未定1种)以及牡竹属5种叶表皮微形态特征进行了观察和研究。所得结果表明气孔保卫细胞上乳突的数目和分布存在一定的规律,并具有一定的分类价值。绿竹亚属的叶表皮微形态特征界于箣竹属和牡竹属之间,但更接近于箣竹属。因此认为在分类处理上,将绿竹亚属置于箣竹属比单独成立绿竹属更为合理。 相似文献
7.
A comparative isoflavonoid analysis of 22 species of Iris, representing almost all the subgenera, and one species of its allied genus Balamcanda, B. chinensis (L.) DC. was carried out
by TLC, with iridin, tectoridin, irigenin, tectorigenin, irisfloretin, dichotomin, wogonin, rhamnazin, apocynin, androsin being used as authentic compounds. The results show that the isoflavones
are the characteristic constituents of Iris and Belamcanda. According to the distribution pattern of
isoflavones, the Iris species here studied can be divided into 2 groups; one contains isoflavonoid aglycons, while the other contains both glycosides and isoflavonoid aglycons. From the point view of
chemosystematics, subgen. Limniris contains isoflavonoid aglycons only and might be a natural
group; subgen. Crossiris might be also a natural group when Iris speculatrix Hance is excluded;
subgen. Pardanthopsis is similar to B. chinensis in the chemical constituent might be a primitive
group in Iris and has close relationship with subgen. Crossiris, subgen. Xyridion and subgen.
Iris. Based on the evidence from phytochemistry, palynology and cytology, Iris cathayensis Migo
and I. mandshurica Pall. are considered intermediate groups between subgen. Limniris and subgen. Iris and I. speculatrix Hance an intermediate group between subgen. Limniris and subgen.Crossiris, while I. confusa Sealy and I. wattii Baker might be conspecific. 相似文献
8.
Xiang Qiu-Yun 《植物分类学报:英文版》1987,25(2):125-131
Cornus L. s. 1. is a large polytypic genus. The classificantion of which has been
so different that some authors recognize several separate genera, while others treat them as either subgenera or sections. New evidence from many disciplines such as palynology, cytology, wood anatomy and embryology supports the view that the genus should remain in the
broad sense. I basically agree with the treatment by Ferguson (1966b) before my finishing
a comprehensive study on Cornus L. s. 1. except for supporting the separation of subgenus
Afrocrania as an independent genus. A new subgenus Sinocornus Q. Y. Xiang, containing
one species, C. chinensis Wangerin, is established here on account of its inflorescence axillary
and different from the other members of the genus which all have terminal inflorescences only.
The inflorescence developed from a terminal bud implicates the sympodial nature of axis of
stem and the one from an axillary bud the monopodial one. It is reasonable to regard the
character as of subgeneric value. Also a new combination, Cornus subgen. Syncarpea (Nakai) Q. Y. Xiang, is proposed here as a substitute for Cornus subgen. Benthamia (C. B. Clarke) Schneider used for a long time. Because the valid publication of the former name subgen.
Syncarpea Nakai is earlier than the latter one. The types of inflorescences of 8 subgenera represented by type or selected species are illustrated. 相似文献
9.
中国鸢尾属植物根茎中异黄酮类成分分布的初步研究及其系统学意义 总被引:5,自引:0,他引:5
本文对鸢尾属Iris 22个种(基本上包括了各个亚属的代表)及其近缘属植物射干属Belamcanda的
射干 B.chinensis(L.)DC.进行了根茎的异黄酮类成分的比较分析研究。结果表明,鸢尾属植物和射干
中普遍具有异黄酮类成分,这是它们的特征性成分之一。根据化学成分的特征,鸢尾属可以分为两大类
群:只含异黄酮甙元的类群和既含异黄酮甙又含甙元的类群。从化学成分的分布特征来看,无附属物亚
属subgen.Limniris只含异黄酮甙元,是一个比较自然的类群。鸡冠状附属物亚属subgen.Crossiris,除小
花鸢尾 I.speculatrix Hance外,是一个较自然的类群。野鸢尾亚属subgen.Pardanthopsis和射干属的成分
非常相似,有着密切的亲缘关系,是鸢尾属中原始的类群。从化学成分特征来看,野鸢尾亚属与琴瓣鸢
尾亚属subgen.Xyridion、鸡冠状附属物亚属、须毛状附属物亚属subgen.Iris都有着一定的联系。根据化
学成分、孢粉学、细胞学等特征,认为:华夏鸢尾I.cathayensis Migo和长白鸢尾I.mandshurica Maxim.为无附属物亚属与须毛状附属物亚属两亚属之间的过渡类型。小花鸢尾是无附属物亚属向鸡冠状附属物亚属过渡的中间类型。扁竹兰I.confusa Sealy和扇形鸢尾I.wattii Baker可能是同一个种。 相似文献
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果皮和种皮微形态特征在杜鹃花属系统学研究中的应用 总被引:12,自引:0,他引:12
采用扫描电子显微镜对国产杜鹃花属Rhododendron6个亚属的代表种和近缘类群杜香属Ledum杜香L.palustre的果皮和种皮微形态特征进行观察,对杜鹃花属植物果皮微形态特征进行了系统描述,并通过比较现存杜鹃花属植物和种子化石,新发现一些居间的种子类型。结果表明,果皮和种皮微形态特征具有一定的系统学意义。叶状苞亚属subgen.Therorhodion的叶状苞杜鹃R.redowskianum的果实有短而疏的刺毛,无气孔,种子为无翅类,扁平,外围轮廓长椭圆形。杜鹃亚属subgen.Rhododendron植物果皮为百合花杜鹃型,具有鳞片,气孔器散生于指状突起之间,与叶表皮的微形态特征一致,其种子为百合花杜鹃型,表面具宽而浅的沟,呈脑纹状,有别于无鳞类杜鹃花。常绿杜鹃亚属subgen.Hymenanthes果皮为云锦杜鹃型,其角质层表面不规则,无表皮毛,偶见气孔;种子为云锦杜鹃型。映山红亚属subgen.Tsutsusi果皮为岭南杜鹃型,密生长表皮毛,角质层致密;种子为南边杜鹃型和岭南杜鹃型。微形态特征与“常绿杜鹃亚属和(国产)映山红亚属均为内部支持率很高的单系类群”的分子系统发育研究结果一致。马银花亚属subgen.Azaleastrum的马银花组sect.Azaleastrum和长蕊杜鹃组sect.Choniastrum微形态区别明显,支持各自为独立的单系类群。羊踯躅亚属subgen.Pentanthera的羊踯躅R.molle果皮特征明显,可与其他亚属区分,但种子类型更接近常绿杜鹃亚属。本研究结合分子系统发育资料和叶表皮微形态特征讨论了一些近缘类群的系统发育关系;研究结果支持将腺萼马银花处理为独立的种。 相似文献
12.
高粱属植物的地理分布 总被引:1,自引:0,他引:1
为探讨高粱属(Sorghum Moench)的系统发育关系,通过野外调查及查阅标本和文献资料,对高粱属植物的地理分布进行了整理和研究。高粱属植物约有29种,分布于全世界热带到温带地区,其中澳大利亚22种,亚洲15种,非洲9种,欧洲3种,地中海2种,美洲6种。中国有5种,分布在东北、西南到华南各省(区)。高粱属有5亚属,仅高粱亚属(subgen.Sorghum)延伸至新世界,其他亚属均分布在旧世界,高粱亚属覆盖非洲并扩散到全世界热带到温带地区;拟高粱亚属(subgen.Parasorghum)分布在非洲、亚洲、澳大利亚;有柄高粱亚属(subgen.Stiposorghum)主要分布在澳大利亚,个别种分布到亚洲;多毛高粱亚属(subgen.Chaetosorghum)分布在澳大利亚;异高粱亚属(subgen.Heterosorghum)分布在澳大利亚和亚洲。这表明澳大利亚东北部是高粱属的现代分布中心和多样化中心,非洲东北部和热带亚洲是否是高粱属的起源地尚需确证。 相似文献
13.
Gilberto Alemán-Sancheschúlz Eloy Solano Teresa Terrazas Jorge López-Portillo 《Physiologia plantarum》2020,169(4):571-585
There are few investigations that analyze the xylem functional anatomy of monocotyledons, as the methods have been developed for woody plants. This study describes the root, rhizome and aerial stem xylem anatomy and functional anatomy of Canna indica, Cyperus papyrus and Phragmites communis grown on flooded substrates; and it aims to evaluate the relationship between the xylem anatomy and its cavitation resistance. To calculate the indexes of vulnerability, mesomorphy, collapse and relative hydraulic conductivity in the three organs mentioned, the diameter, number of vessels per mm2, thickness of the walls and the length of the tracheal elements were recorded. In addition, the xylem specific conductivity of the aerial stem was measured with the pipette method, and its resistance to cavitation was determined experimentally by the air injection technique. The protoxylem is xeromorphic, it has longer vessel elements, smaller diameters, thin walls and scalariform perforation plates, whereas the metaxylem is mesomorphic, with shorter vessel elements, larger diameters, thicker walls and simple perforation plates. Both present low collapse resistance but have a high relative hydraulic conductivity. P. communis recorded the highest cavitation resistance, and the number of vessels per mm2 was related to xylem cavitation resistance in Canna indica and Cyperus papyrus. The experimental results of this investigation match partially the anatomical indexes and showed that the xylem of these species has a low specific conductivity and is more vulnerable to cavitation than that of other monocots. 相似文献
14.
Seventy-three species from 17 genera of Cyperaceae were studied with the aim of identifying and confirming those species with Kranz anatomy. Among the species studied, 36 exhibited Kranz anatomy; 37 did not. Of the four types of Kranz anatomy recognized in Cyperaceae, three were encountered: the chlorocyperoid type in the genera Cyperus, Kyllinga, Lipocarpha, Pycreus, and Remirea; the fimbristyloid type in Abildgaardia, Bulbostylis, and Fimbristylis; and the rhynchosporoid type in Rhynchospora. Non-Kranz anatomy was confirmed in species of the following genera: Becquerelia, Calyptrocarya, Cyperus, Diplacrum, Eleocharis, Fuirena, Hypolytrum, Pleurostachys, Rhynchospora, and Scleria. The anatomical data obtained corroborate earlier studies of species of Cyperaceae as to the presence of Kranz anatomy and the anatomical types in several species and the “Kranzkette” pattern in Cyperus ligularis and Cyperus pohlli. 相似文献
15.
杜鹃花属植物的可育性研究进展 总被引:2,自引:0,他引:2
结合作者近年来的工作, 总结了国内外有关杜鹃花属(Rhododendron)植物可育性研究的成果和进展, 旨在为相关研究者和技术人员提供参考。(1)杜鹃花属的杜鹃亚属(subgen. Rhododendron)和羊踯躅亚属(subgen. Pentanthera)中存在多倍化现象, 甚至存在同一物种有多种倍性。(2)在自然授粉条件下, 除了常见种内杂交及自交情形外, 常绿杜鹃亚属(subgen. Hymenanthes)、杜鹃亚属和映山红亚属(subgen. Tsutsusi)内种间杂交十分普遍, 也有跨亚组之间的自然杂交案例。(3)杜鹃花属植物中自交亲和(self compatibility, SC)与自交不亲和(self incompatibility, SI)现象并存, 云锦杜鹃亚组(subsect. Fortunea)兼具自交败育到高可育性的所有类型, 而在映山红亚属与马银花亚属(subgen. Azaleastrum)中自交不亲和现象则更为常见。通常自交被认为是杜鹃花物种的被动适应, 但对于一些在极端气候条件下分布的局域种而言, 则可能是一种主动响应。(4)不同分类等级(亚属、组和亚组)间的人工杂交研究表明, 杂交亲和性或可育性与双亲的系统发育关系及染色体倍性具有明显的关联, 并反映在发育阶段和各项亲和力指标的变化之中。常绿杜鹃亚属与杜鹃亚属间的远缘杂交相对比较容易, 常绿杜鹃亚属与映山红亚属间、映山红亚属与杜鹃亚属的正反交、映山红亚属与羊踯躅亚属的正交以及常绿杜鹃亚属与羊踯躅亚属的正交、马银花亚属与杜鹃亚属正交等也有亲和的案例。(5)自交不亲和亲本的介入可大幅度增加种间杂交的不育比率, 并导致其由双向可育到单向不育再到双向不育方向发展。 相似文献
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Rhododendron is the largest genus within the subfamily Rhododendroideae, which has about 1000 known species in the world and more than 500 species in China. Since the genus was established by Linnaeus, its infrageneric relationships have been well studied by many taxonomists on the basis of morphological characters and molecular data. In 1996, Chamberlain et al. proposed a new system of Rhododendron with eight subgenera, i.e., Azaleastrum, Candidastrum, Hymenanthes, Mumeazalea, Pentanthera, Rhododendron, Therorhodion, and Tsutsusi. In this paper, micromorphological characters of leaf epidermis in 4 varieties, 48 species, 6 subgenera of Rhododendron from China were examined using light microscopy (LM) and scanning electron microscopy (SEM). Leaf epidermal features are described and micromorphological types are distinguished here according to morphological characters such as scale, gland, foliar trichome and stomatal apparatus of leaf epidermis. It is shown that the leaf epidermal cells are usually irregular or polygonal in shape. The patterns of anticlinal walls are straight, arched or undulate. The stomatal apparatuses are anomocytic and are usually found on abaxial, not adaxial, epidermis. The results also show that: (1) the lepidote rhododendron (i.e., subgen. Rhododendron), which has both scales and papillae on leaf epidermis, differs distinctly from the elepidote rhododendron; (2) three types of leaf epidermis are identified in subgen. Hymenanthes (i.e., R. fortunei-type, R. chihsinianum-type and R. simiarum-type), whereas four in subgen. Tsutsusi (i.e., R. mariesii-type, R. simsii-type, R. mariae-type and R. flosculum-type); (3) except for R. westlandii and R. henryi, the species of subgen. Azaleastrum show similar morphological characters, i.e., dense stomatal apparatuses surrounded by ringed or discontinuous striates; (4) R. molle of subgen. Pentanthera differs from the species of other subgenera on morphological characters such as foliar trichomes, dense stomatal apparatuses with asymmetrical outer stomatal rims surrounded by undulate-striates, and no gland; (5) only R. redowskianum is found with distinct T-pieces at the polar region of guard cells in Rhododendron. The results support the conclusion inferred from molecular systematic studies that subgen. Therorhodion is the basal clade of Rhododendron. Finally, the relationships between the closely related species are also discussed on the basis of leaf epidermal features. 相似文献
18.
通过样线法调查福建省大田县大仙峰野生杜鹃属(Rhododendron)植物资源,掌握其种类及形态特征、适生环境、花期等特性。大仙峰共记录11种杜鹃属植物,分属4亚属,其中映山红亚属3种、马银花亚属4种、常绿杜鹃亚属3种、羊踟蹰亚属1种,种类不同,花期、花色均有所不同。从春季开始至夏季均可欣赏到不同景色的杜鹃。对溪畔杜鹃(R. rivulare)、羊踯躅(R. molle)2种杜鹃进行扦插育苗,二者成活率皆在45%以上,达到资源保存的目的。大仙峰杜鹃属植物种质资源丰富,类型多样,分布范围广,有较大的开发潜力和应用前景。 相似文献
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中国杜鹃花属的叶表皮特征及其系统学意义 总被引:15,自引:0,他引:15
通过光学显微镜和扫描电镜对国产杜鹃花属Rhododendron6个亚属48种4变种植物的叶表皮特征进行观察,结果表明叶表皮的鳞片、腺体、表皮毛的有无和气孔器的类型具有一定的系统学意义。光学显微镜下可见:叶表皮细胞形状为多边形、不规则形,垂周壁式样为较平直、浅波状和波状.气孔器普遍存在于下表皮,上表皮未见气孔器分布,其类型均为无规则形。杜鹃亚属subgen.Rhododendron叶表皮具有鳞片,在扫描电镜下可见气孔器散生于指状突起之间,有别于无鳞类杜鹃花。常绿杜鹃亚属subgen.Hymenanthes和映山红亚属subgen.Tsutsusi有多种不同叶表皮类型;除了凯里杜鹃R.westlandii和弯蒴杜鹃R.henryi形态较特殊之外,马银花亚属subgen.Azaleastrum的马银花组sect.Azaleastrum和长蕊杜鹃组sect.Choniastrum微形态区别不明显。羊踯躅亚属subgen.Pentanthera的羊踯躅R.molle叶表皮有表皮毛,无腺体,气孔器密生,外拱盖形状不对称,外围有多层波形条纹突起可与其他亚属区分:而叶状苞亚属subgen.Therorhodion的叶状苞杜鹃R.redowskianum保卫细胞有明显的T型加厚,与其他亚属种类明显不同,与分子系统发育研究得到的“叶状苞亚属是杜鹃花属的基部类群”的结果吻合。本研究还依据叶表皮微形态特征讨论了一些近缘种类的关系。 相似文献