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1.
1971年,N.Ulzijkhutag根据采自阿拉善戈壁(=Bordzon-Go-bi)的标本(1970-07-29,V.I.Grubov,N.Ulzijkhutag et G.Tserendalzhid,无号)发表新种Oxytrops grubovii,并以此建立新组Oxytropis subgen.Traganthoxytropis sect.Monan-thos;1987年,G.P.Yakovlev将O.grubovii归入海绵豆属Spongiocarpella;1988年,张振万同意N.Ulzijkhutag的意见,并根据刺垫棘豆之龙骨瓣无喙等特征将Ulzijkhutag的刺  相似文献   
2.
对中国堇菜属美丽堇菜亚属植物进行了系统学修订,确认中国堇菜属美丽堇菜亚属植物共有6种,列出分种检索表,对《中国植物志》51卷中未记载的3种进行了详细的描述,并对塔城堇菜、深紫堇菜及隐距堇菜进行了绘图。  相似文献   
3.
Daniel E. Atha 《Brittonia》2008,60(2):185-189
Acalypha gentlei is described, illustrated and mapped. The species is endemic to Belize and adjacent areas of Mexico and Guatemala and restricted to semi-deciduous moist forests on limestone. The species is referred to Acalypha subgenus Linostachys.
Resumen  Se describe, ilustra y grafica la distribución de Acalypha gentlei. Esta especie nueva es endémica a Belice y áreas adyacentes de México y Guatemala, y está restringida a bosques húmedos semi-deciduos sobre caliza. La especie es referida a Acalypha subgénero Linostachys.
  相似文献   
4.
庄平 《广西植物》2018,38(12):1558-1565
为探索杜鹃花亚属内异种杂交的可育性及其规律,对杜鹃亚属有鳞大花亚组(subsect. Maddenia)、三花杜鹃亚组(subsect. Triflora)、亮鳞杜鹃亚组(subsect. Heliolepida)及腋花杜鹃亚组(subsect. Scabrifolia)等4亚组10个杜鹃花种类的22个杂交组合(其中18个数据完整组合)的可育性进行了研究。结果表明:(1)所涉及的杜鹃亚属不同亚组间及三花杜鹃亚组内杂交均较困难,在18个数据完整组合中高可育与可育组合比率明显偏低,不育比率高(55.6%)。(2)在10个不可育或败育组合中,不能坐果(Cab型)、不能结实(Sab型)和可结实而种子不能发芽(Sng型)的数量分布为6∶1∶3,其不亲和或败育发生的阶段可能涵盖了从前合子期到后合子期的整个阶段。(3)亲本一方为多倍体组合的可育率(41.6%),尤其是母本为多倍体时,比二倍体组合的可育率(50.0%)低且无高可育组合出现,部分印证了倍性是导致该亚属植物不同种类杂交不亲和、不育与育性下降的重要原因,但不是唯一原因,亚组间杂交的可育率(16.7%)明显低于亚组内(三花杜鹃亚组内,58.3%)。(4)与相应的母本自然授粉结果相比,杂交明显导致多数可育组合绿苗率比率和单位可育种子数量比率的大幅度下降,这是双亲遗传差异及多倍体亲本介入后所导致的杂交衰退hybrid weakness现象。(5)在多倍体作母本的情况下,杂交单向不育或非对称遗传渗透现象明显。  相似文献   
5.
Eighty-four pollen samples were obtained for 80 taxa, of which, 13 species and one variety are from sect. Brachycalyx Sweet, 58 species and two varieties from sect. Tsutsusi Sweet, and six species from subgen. Pentanthera (G. Don) Pojarkova, respectively. Pollen morphology of all samples was observed using LM and SEM. Pollen grains are revealed to be spheroidal and tetrahedral with tricolporate apertures. Pollen sizes of subgen. Tsutsusi (Sweet) Pojarkova range from 37.67 μm to 61.06μm, and the exine sculptures are more or less compactly granulated. Pollen sizes are significantly different between sect. Brachycalyx and sect. Tsutsusi of subgen. Tsutsusi. Rhododendron tashiroi Maxim. of sect. Tsusiopsis Sleumer shows a close affinity to sect. Brachycalyx. Pollen size and exine are consistent with general morphology in differentiating species in sect. Tsutsusi. Rhododendron huadingense B. Y. Ding & Y. Y. Fang, once placed as a member of sect. Brachycalyx, should be considered as a species in subgen. Pentanthera.  相似文献   
6.
7.
王开运  陈新露   《广西植物》1990,10(2):121-126+187
本文应用光学显微镜与扫描电子显微镜观察了山茱萸科Cornaceae4属(按照Wangerin1910年的概念)27种花粉形态,结果如下: 1.根据花粉特征,支持把青荚叶属Helwingia,桃叶珊瑚属Aucuba,鞘柄木属Torricellia三属分别独立成科的观点。 2.梾木属Cornus可明显区分为两种类型,即梾木型和四照花型;梾木型还可再分为三个亚类型.即灯台树亚型,长圆叶梾木亚型和梾木亚型。 5.支持四照花属应从梾木属中分出而独立成属;而在四照花属Dendronbenhamia下设立北美四照花亚属Subg. Apocarpea和四照花亚属Subg. Syncarpea;在梾木属下设立梾木亚属Subg. kraniopsis, 灯台树亚属Subg.Masomora等亚属的观点。 4.建立了—新亚属——长圆叶梾木亚属。  相似文献   
8.
The fruits of 10 species of Solanum sect. Acanthophora were studied. Cross and/or longitudinal and/or tangential microtome sections, stained mostly with astra blue/basic fuchsin, were made for microscopic examination. Three different kinds of cells were found in the epidermis, immediately below which a hypodermis, consisting in any of four types of structures, was always found. The mesocarp exhibits two histologically differentiated zones, an external one (formed by normal or spongy parenchyma, according to the species), and an internal one, commonly juicy, and with proliferations among the seeds. The diagnostic value of all these structures is assessed. Morpho-anatomical information is used to define fruit types beyond the berry, traditionally described for Solanum, and the probable dispersal syndrome related to them is discussed. Fruit similarities are slightly noticeable in several cases, while differences may be the result of their sexual system – which affects specially the size – and their histology, which is related to the dispersal syndrome. The comparison of our data with previous molecular phylogeny of the section suggests that a significant morphological variation is not associated with significant DNA sequence changes.  相似文献   
9.
将杜鹃花属马银花亚属Rhododendron subgen. Azaleastrum的凯里杜鹃R. kailiense Fang &; M. Y. He和线萼杜鹃R. linearicupulare Tam处理为南海杜鹃R. westlandii Hemsl.的异名, 鹿角杜鹃R. latoucheae Franch.处理为西施花R. ellipticum Maxim.的异名, R. esquirolii Lévl.处理为长蕊杜鹃R. stamineum Franch.的异名, 山荷桃R. championae Hook. var. ovatifolium Tam处理为刺毛杜鹃R. championae的异名, 并作了相应的讨论。  相似文献   
10.
The somatic karyotypes of 10 taxa belonging toAllium subgen.Molium (Liliaceae) from the Mediterranean area have been investigated using Giemsa C-band and fluorochrome (Hoechst, Quinacrine) banding techniques. A wide range of banding patterns has been revealed. InAllium moly (2n = 14),A. oreophilum (2n = 16) andA. paradoxum (2n = 16) C-banding is restricted to a region on each side of the nucleolar organisers and the satellites show reduced fluorescence with fluorochromes. The satellites are also C-banded and with reduced fluorescence inA. triquetrum (2n = 18), but two other chromosome pairs also have telomeric bands which are not distinguished by fluorochrome treatment. InA. erdelii (2n = 16) 4 pairs of metacentric chromosomes have telomeric C-bands while 2 pairs of telocentric chromosomes have centromeric C-banding. InA. subhirsutum (2n = 14),A. neapolitanum (2n = 28),A. trifoliatum subsp.hirsutum (2n = 14) andA. trifoliatum subsp.trifoliatum (2n = 21) chromosomes with long centromeres, consisting of a centromere and nucleolar organiser are positively C-banded on each side of the constriction. InA. subhirsutum banding is confined to the pair of chromosomes with this feature, whereas inA. neapolitanum one additional chromosome pair has telomeric bands and inA. trifoliatum there are varying numbers of chromosomes with centromeric and telomeric bands, depending on the subspecies.A. zebdanense (2n = 18) shows no C-bands. The banding patterns in this subgenus are compared with those recorded for otherAllium species and with the sectional divisions in the genus. Evidence from the banding patterns for allopolyploidy inA. trifoliatum subsp.trifoliatum andA. neapolitanum is discussed.  相似文献   
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