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中国红豆杉属和白豆杉属的核形态学研究 总被引：7，自引：0，他引：7
报道了红豆杉属Ｔａｘｕｓ３种１变种及白豆杉属Ｐｓｅｕｄｏｔａｘｕｘ １种的核形态结构２,啼杉属３种１变种和白豆杉的间期核要形都为复杂染色中心型,前期染色体属于中间型,体细胞中期染色体分别为：（１）红豆杉Ｔａｘｕｘ ｃｈｉｎｅｎｓｉｓ Ｒｅｈｄ ．Ｋ＝２４＝２０ｍ＋２ｓｍ＋２Ｔ,着丝点端化值为５８．２２％;（２）南方啼杉Ｔ．ｃｈｉｎｅｎｓｉｓ Ｒｅｈｄ ｖａｒ．ｍａｉｒｅｉ Ｃｈｅｎｇ ｅｔ Ｌ．Ｋ 相似文献
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对蓝钟花属(Cyananthus)11种植物的种子在体视显微镜和扫描电镜下的外部形态、内部结构以及微形态特征进行研究.结果表明:蓝钟花属种子呈窄卵形,表面光滑,颜色多为黑色、褐色至棕色,其中多年生组表面具有特殊黑色斑纹;胚属短小型,胚乳白色或棕色,胶质或脂质;种皮表面纹饰为条纹型,网壁螺旋排列或平行排列,又可细分为阔网状条纹、窄网状条纹与一般性条纹三种类型.种子形态在属下三组间差异明显,种子长度、表面颜色及表面纹饰为属内组的划分提供了重要依据.此外,一年生组各种在种子形态上分化最为明显,可能与其较强的适应性有关. 相似文献
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刘丽仙；刘万辉；陈晓蕾 《武汉植物学研究》1992,10(3):219-225
本文应用扫描电镜等较先进的实验研究方法,对水栀子(大花栀子Gardeniajdsminoides Ellis. var. grandiflora Nakai. 的果实)进行了形态学和组织学研究。发现其侧膜向果腔延伸,并产生桔红色的、肉质分枝的假隔膜,其与种子相间排列并将种子包裹而交结成球状体,种皮石细胞五面增厚,细胞腔中填充色素块,薄壁细胞富含栀子索等,特征明显,为水栀子的鉴定提供了重要的科学依据。水栀子所含的色素和药用有效化学成分栀子甙较栀子高,对水栀子进一步的开发利用,向人们显示了可观的前景。 相似文献
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国外动物形态学在50年代经历了低谷阶段,而近20年又呈现出生机蓬勃的局面。无论从学科内容上还是从方法学上都有了许多更新,使这门古老的学科又焕发出青春。 20世纪50年代——解剖学的衰落动物形态学被认为是生物学科中历史最悠久的领域,也同样地被认为是生物学各分支学 相似文献
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利用解剖镜和扫描电镜对小檗科5属(小檗属、十大功劳属、鬼臼属、山荷叶属和红毛七属)40种2变种植物种子形态进行观察。研究结果表明:小檗科植物种子颜色多为黄褐色、红棕色至黑色,形状多样;种皮纹饰可分为网纹型、网纹—梯纹型、梯纹型和嚼烂状4种类型,其中网纹型又可划分为7个亚型。种子球形、种脐位于种子侧面近中部可作为红毛七区别于其他属种子的重要形态特征。根据种皮微形态特征,探讨了种子形态在小檗科内的系统学意义,并推测了种皮纹饰的可能演化路线。种子形态支持小檗属和十大功劳属的近缘关系,认为鬼臼属(八角莲属)较山荷叶属分化更早,但不支持Ahrendt对小檗属下组和亚组的划分。 相似文献
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A common terminology for the external morphological characters of centipedes (Chilopoda) is proposed. Terms are selected from the alternatives used in the English literature, preferring those most frequently used or those that have been introduced explicitly. A total of 330 terms are defined and illustrated, and another ca. 500 alternatives are listed. 相似文献
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LIMIN LU JUN WEN ZHIDUAN CHEN 《Botanical journal of the Linnean Society. Linnean Society of London》2012,168(1):43-63
Parthenocissus (the Virginia creeper genus, Vitaceae) consists of 13 species and shows a disjunct distribution between Asia and North America. We investigated the inflorescence structure, calyx morphology, appendages on the inner side of petals, leaf epidermis, pollen and seed characters throughout the genus. A combined phylogenetic analysis with 27 morphological and 4137 molecular characters was conducted and the result was largely congruent with that of the previous molecular work, but with higher resolution. The combined analysis identified two clades corresponding to the Asian and North American taxa. Parthenocissus feddei was resolved as closely related to the clade containing P. cuspidifera, P. heterophylla and P. semicordata. The four species share synapomorphies of having conspicuously raised veinlets, an obscurely five‐ (to eight‐) lobed calyx, appendages on the inner side of petals covering the entire length of anthers and foveolate pollen exine ornamentation. Within the Old World clade, the pentafoliolate species were weakly supported as more closely related to species with both simple and trifoliolate leaves. Furthermore, the ancestral states of tendril apices, inflorescence structure, appendages on the inner side of petals and exine ornamentation of pollen grains were reconstructed on the molecular strict consensus tree. The appendages on the inner side of petals and exine ornamentation of pollen grains were suggested to be important characters in the taxonomy of Parthenocissus, especially for species with trifoliolate leaves. Finally, the previous classifications of Parthenocissus were evaluated within the phylogenetic framework. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, ?? , ??–??. 相似文献
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MARÍA CAPA PAT HUTCHINGS RACHAEL PEART 《Zoological Journal of the Linnean Society》2012,164(2):245-284
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Eileen J. Cox 《Journal of phycology》2012,48(1):1-31
This article reviews current knowledge of wall morphogenesis in pennate diatoms in relation to the way characters are defined and described for taxonomic and systematic analyses. It argues that an understanding of ontogeny is essential for the accurate identification of character homologies, which in turn must underpin all phylogenetic and systematic analyses. Terminology should reflect character homology, but most diatom terminology fails to do this, with concomitant confusion and potential taxonomic mistakes. Identifying where information is lacking or misinterpreted are first steps toward improving our understanding of diatom structure and relationships. After reviewing the current knowledge on pennate diatom structure and its development, this article briefly discusses the significance of morphological variation, character polarity, and the vital importance of applying diatom terminology correctly. 相似文献
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八角属（八角科）植物的种子形态 总被引：3，自引：1，他引：3
在光学显微镜和扫描电镜下对八角属(Illicium Linn.) 15种植物（33个样品）的种子形态进行了观察和描述。八角属植物种子形态多为倒卵球形,少椭球形或卵球形,侧向压扁;外种皮石质,中种皮革质,内种皮膜质;外种皮淡黄色、卵黄色至橙褐色,具蜡被,极光滑,有光泽,无纹饰,腹部有一凸起的纵棱（种脊）,由种脐延伸至顶端;种脐位于基端偏向腹部一侧或位于基端,卵形或椭圆形,下凹;胚微小,胚乳丰富,含油。该属植物种子的形态特征非常相似,表明该属是一个自然的单系类群。 相似文献
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STEPHAN IMHOF MOSES N. SAINGE 《Botanical journal of the Linnean Society. Linnean Society of London》2008,157(1):31-36
The complete ontogeny of the mycoheterotrophic Afrothismia hydra (Burmanniaceae) from seed to seed dispersal is presented. The oblong–ovoidal seeds are up to 0.7 mm long. They germinate with root tissue only, disrupting the seed coat and developing a primary ovoid root tubercle. At the proximal end of the tubercle, a second tubercle arises and further root initials indicate the sequential growth of more root tubercles with filiform extensions resulting in a small root aggregate. The seed coat often remains attached to this structure. When the root aggregate enlarges, a central axis to which all roots are connected becomes visible. This axis has a growth pole where new root tubercles arise. The same growth pole will later develop into a stem with scale leaves finally terminating in a flower. Flowers develop sympodially when the mature plant is only several centimetres long. After anthesis, the corolla tube disintegrates, leaving a pyxidium which opens by means of a peculiar elongating placenta, here called 'placentophore'. The placentophore elevates the placenta with attached seeds above the flowering level and is interpreted as an adaptation to ombrohydrochory. The reduction of hypocotyl, cotyledon and primary shoot is discussed with regard to the classical germination concepts of monocotyledons and with mycoheterotrophic dicotyledons. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 31–36. 相似文献
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孙成仁在2002年《植物分类学报》第40卷第2期“五味子科植物种子表面微形态及其系统学意义”一文中对林祁(2000)所做的五味子科分类学修订提出了不同的看法。本文对此作出解答,认为由于双方在实验材料、实验方法、实验结果、植物分类学研究方法等方面存在差异,从而得出不同的研究结论。 相似文献
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VICTORIA SOSA HELGA OCHOTERENA MANUEL ESCAMILLA 《Botanical journal of the Linnean Society. Linnean Society of London》2006,152(1):1-13
Cerdia is a poorly understood genus of minute cushiony plants endemic to Mexico that is traditionally placed in subfamily Paronychioideae, tribe Polycarpeae (Caryophyllaceae). Morphological observations and phylogenetic analysis of ITS DNA sequences were carried out to determine the number of species, heretofore controversial, that constitute the genus as well as its position within Caryophyllaceae. Samples of Cerdia were collected through its entire range of distribution and together with previous specimens were used in morphological analyses. Nineteen terminal taxa were considered in a phylogenetic analysis with representatives of the different lineages in Caryophyllaceae. Results indicated that Cerdia is a monotypic genus, including only one variable species, C . virescens , but its phylogenetic affinities remain doubtful. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 1–13. 相似文献
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Y. S. Athugala K. M. G. G. Jayasuriya A. M. T. A. Gunarathne C. C. Baskin 《Plant biology (Stuttgart, Germany)》2018,20(5):916-925
- Fruiting season of many Sri Lankan tropical montane species is not synchronised and may not occur when conditions are favourable for seedling establishment. We hypothesised that species with different fruiting seasons have different seed dormancy mechanisms to synchronise timing of germination with a favourable season for establishment. Using six species with different fruiting seasons, we tested this hypothesis.
- Germination and imbibition of intact and manually scarified seeds were studied. Effect of GA3 on germination was examined. Embryo length:seed length (E:S) ratio of freshly matured seeds and of those with a split seed coat was determined. Time taken for radicle and plumule emergence and morphological changes of the embryos were recorded.
- The radicle emerged from Ardisia missionis, Bheza nitidissima and Gaetnera walkeri seeds within 30 days, whereas it took >30 days in other species. Embryos grew in seeds of B. nitidissima and G. walkeri prior to radicle emergence but not in Microtropis wallichiana, Nothapodytes nimmoniana and Symplocos cochinchinensis. A considerable delay was observed between radicle and plumule emergence in all six species. Warm stratification and/or GA3 promoted germination of all species.
- All the tested species have epicotyl dormancy. Seeds of B. nitidissima and G. walkeri have non‐deep simple morphophysiological epicotyl dormancy, and the other four species have non‐deep physiological epicotyl dormancy. Differences in radicle and epicotyl dormancy promote synchronisation of germination to a favourable time for seedling development. Therefore, information on dormancy‐breaking and germination requirements of both radicle and epicotyl are needed to determine the kind of dormancy of a particular species.
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以晋西北丘陵风沙区不同种植年限(6、12、18、40和50 年)人工柠条的3种大小类型种子为对象,分析不同年限柠条种子形态特征,从繁殖策略的角度探讨人工植被恢复潜力。结果表明:人工柠条的结实量随着种植年限的增加总体呈上升趋势,在种植50年达到最大值(584粒·株-1);种子长度、种子宽度、种子形状指数随着种植年限的增加总体呈下降趋势,在种植50年达到最小值(5.09 mm、2.76 mm、0.05);种子萌发率随种植年限的增加呈上升-下降-上升的波动变化趋势,在种植12年达到最大值(97.2%)。结实量与种子重量呈显著负相关。种子萌发率与种子重量密切相关,重量小的种子萌发率低,更易于形成持久种子库。相关分析表明,结实量与株高、地上生物量和地下生物量呈显著正相关;种子形状与新枝数呈显著负相关。这表明随着种植年限的增加,柠条繁殖对策由种植前期(6～12年)大种子较多的K策略向种植后期(18～50年)小种子逐渐为主的r策略转变,即柠条既要保证繁殖体数量,又要保证繁殖体的持久性,从而产生了数量更多的小而圆的种子。 相似文献