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The genus Cyclocodon Griff. was reduced by C. B. Clarke in 1881 into a sectionof the genus Campanumoea. Our LM and SEM observations on pollen morphology showthat the pollen of all the three species in the former is 3-colporate with the exine sparselyhigh-spinulose, whereas that of the two species in the latter is 5~8-colpate with the exinerelatively densely short-spinulose. SEM observations on seed-coat indicate that the primaryornamentation of the seed-coat of the two species in Campanumoea (s. str. ) is characterizedby regular and polygonal areoles which are much larger than the radial walls in diameter andby the bead-like secondary ornamentation on the radial walls, while that of the three speciesin Cyclocodon is characterized by irregular-shaped areoles which are nearly equal to the radialwalls in diameter and by the rope-like secondary ornamentation on the radial walls. Thus,the pollen morphology is closely correlated with the seed-coat morphology. Taking the characteristics of pollen, seed-coat and gross morphology into consideration, the genus Cyclocodon is restored, separate from Campanumoea (s. str. ). One new combination, Cyclocodon celebicus (B1.)Hong, is made in the present paper. The genus Cyclocodon is con-sidered closely related to Platycodon rather than to Campanumoa. 相似文献
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轮钟花属的恢复及其花粉和种皮证据 总被引:4,自引:0,他引:4
光学显微镜和扫描电镜观察表明,金钱豹属(广义)花粉明显分为两个类型:Campanumoea inflata和C.javanica subsp.laponica的花粉5~8沟,外壁具相对密的短刺,刺高不过1μm,而C.lancifolia,C.celebica和C.parviflora的花粉3孔沟,外壁刺稀疏,高于2μm。种子表面纹饰也同样可分为 两类,前两个种一类,其种子表面网状,网眼规则而多角形,直径大于网脊宽度,网脊上的次级纹饰为念 珠状,而后三种为一类,其种子表面网眼不规则,直径与网脊宽度近相等,网脊上的次级纹饰绳索状。可 见花粉特征与种皮性状是高度相关的。后三个种所属的分类群就是被归并了的属Cyclocodon Griffith。 综合花粉、种皮及外部形态,这个属应予恢复。其近缘属应是Platycodon,而不是Campanumoea。 相似文献
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对93株六倍体小黑麦×普通小麦杂种F_1花粉植株进行了细胞学观察,Giemsa分带鉴定黑麦染色体,分析花粉植株中D、R染色体的分布组成。花粉植株染色体数目集中在2n=23附近,D、R两组染色体表现不同的数量分布:黑麦(R)染色体从数量上趋于随机分布;小麦(D)染色体却趋于大部分保留。初步分析了产生这种现象的原因。 相似文献
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从12例硬皮病患者的抗染色体抗血清中发现4例是抗中期染色体鞘的,用它们和小鼠腹水癌细胞核及全细胞裂解液SDS-PAGE的蛋白印迹相反应,结果显示它们和细胞核裂解液的11条抗原蛋白相结合,而且和全细胞裂解液中除以上的11条外的另8条相结合。 相似文献
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大肠杆菌的dnaA46突变能被F′质粒整合抑制。整合抑制的菌林(Sin菌株)在通过转导引入了recA56突变后又变得不能在40℃中生长。标记转移、吖啶橙敏感性,F′质粒消除和mini-染色体质粒转化等实验说明,Sin菌株中F′质粒始终处于整合状态,并且在40℃中细菌染色体的复制由整合状态的F′质粒所带动。比较了Sin recA~ 和Sin recA~-菌株在不同温度中的DNA、蛋白质的生物合成情况。实验结果说明recA基因在DNA复制过程中起作用。前人的工作证明了recA基因在DNA重组和DHA损伤应急修复(SOS)过程中是一个关键的基因。本文的工作为recA基因的功能提供了新的认识。 相似文献
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Pampanini于1910年发表了桔梗科采自湖北西部的一个新种Codonopsis draco。此后100年无人提起它。最近作者在进行党参属及其近缘类群的专著研究中发现它就是1984年发表的刺萼参Echinocodon lobophyllus D.Y.Hong,也采自湖北西部。本文作了新组合。刺萼参在湖北郧西的分布点已经消失,至今仅知道陕西东南部两个地点有少量植株,可见刺萼参已处于濒危状态。因为它是单种属,对其保护应予特别关注。 相似文献
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Recovery of doubled haploid (DH) progeny from haploid melon plants for use in breeding programs requires efficient chromosome doubling procedures. We describe improved procedures for recovery of fruits and viable seeds from parthenogenetic melon plants. Plant regeneration from nodal explants treated with 500 mg/L colchicine for 12 h was increased from 40 to 88% by transferring the treated explants to medium supplemented with a combination of growth regulators [5 μM IAA; 5 μM BA; 1 μM ABA; 30 μM AgNO3). Prolonged exposure (2–7 days) to colchicine inhibited regeneration from nodal explants but had less effect on shoot tip explants. Many colchicine-treated plantlets flowered in vitro, allowing early assessment of their male fertility. Production of stained pollen in plants from nodal explants was highest after 0.5–2 days of colchicine treatment and on plants from shoot tips after 1–2 days. In vitro pollen counts correlated well with counts from greenhouse grown plants and with fruit set. The fruit set rate for colchicine-treated plants with a high pollen number was 47%. Appropriate colchicine treatment and culture of nodal explants as well as tip explants can substantially increase the number of fertile plants and DH lines recovered from parthenogenetic melons. 相似文献
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Two new species of Codonopsis, namely C. parvitubulosa Z. T. Wanget G. J. Xu and C. retroserrata Z. T. Wang et G. J. Xu are described 相似文献
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人乳头瘤病毒(Human Papillomavirus,HPV)复制机制的研究,对复制与宫颈病变的相关性可提供重要的依据。HPV是有衣壳包裹的小型环状双链DNA病毒。其基因组可分早期及晚期蛋白编码区和一个调控区。高危型HPV通过E1、E2蛋白及Ori序列启动复制。高危型HPV在宫颈上皮细胞中的复制是分化依赖型的,在高危型HPV感染的成熟的宫颈表皮细胞中,HPV E7蛋白使细胞再次进入增殖分裂期,HPV-DNA得以复制,但同时E7蛋白亦会诱发宿主细胞染色体不稳定,增加癌变风险。由此推理,高危型HPV的复制与宫颈癌的发病有一定相关性。目前有学者对高危型HPV的复制机制,复制与致癌的关系方面正开展相关研究。 相似文献
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A new symmetrical phenylpropanoid glycoside, tangshenoside VIII (1), together with six known tangshenosides (2–7) were isolated from the roots of Codonopsis lanceolata (Campanulaceae). Their structures were established on the basis of spectroscopic data, including two-dimensional NMR analyses. Tangshenosides have chemotaxonomic significance. 相似文献
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泛素/蛋白酶体系统(UPP)是真核细胞内蛋白质选择性降解的主要途径,而蛋白酶体是UPP中蛋白质降解的场所。本文应用细胞学、统计学方法以及FTIR技术研究了蛋白酶体抑制剂MG132对青扦(Pecea wilsonii)花粉萌发、花粉管生长的影响。结果表明:MG132显著抑制青扦花粉萌发和花粉管生长,并导致花粉管形态异常,主要表现为花粉管亚顶端出现液泡化,并且液泡随着培养时间的延长而扩大到整个花粉管,花粉管濒临死亡;而DMSO以及非蛋白酶体抑制剂E-64不产生类似结果;半薄切片结果表明,MG132处理后不仅花粉管细胞质发生液泡化,生殖细胞也发生液泡化;FTIR分析进一步表明,MG132处理后,花粉管顶端的细胞壁蛋白和果胶质含量大幅度下降。上述结果表明:MG132通过抑制蛋白酶体活性显著影响青扦花粉萌发及花粉管生长;UPP在青扦花粉萌发、花粉管极性生长模式的建立和维持过程中起重要作用;抑制蛋白酶体活性将导致青扦花粉管的程序性死亡。 相似文献
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YANG Qin-Er 《植物分类学报:英文版》2000,38(6):551-556
Ranunculus wangianus Q. E. Yang is described as new. This species, a hexaploid with2n = 6x = 48, is different from its closet ally, R. yunnanensis, a diploid with 2n = 2x = 16, in thecharacters of foliage. It is also somewhat similar to R. felixii Lévl., but the latter is a tetraploidwith 2n = 4x = 32, usually with only one basal leaf and the roots are thickened from base andfleshy. 相似文献
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云南西北部毛茛属一新种——文采毛茛及其核型 总被引:4,自引:1,他引:3
描述了云南西北部毛茛属一新种——文采毛茛R.wangianus Q.E.Yang。该种与云南毛茛 Ranunculus yunnanensis Franch.十分相似,但在叶的质地和形状以及染色体数目方面明显不同。与扇叶毛茛R.felixii Lévl.也相似,但后者为四倍体,须根基部肉质肥厚成纺锤形,基生叶通常1枚,叶片肾状圆形至扇形而易于区别。首次报道了云南毛茛、扇叶毛茛和文采毛茛的染色体数目和核型。 相似文献
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Tetraena Maxim. is an endemic genus of Inner Mongolia and the desert regionof Central Asia. It is also a rare and endangered plant. Some botanists had made some researchon the systematic positions of this genus, but their views are debatable. Through a comprehensivestudy: research history, morphology (pistil, fruit), pollen grains, chromosomes, the authors suggest that this genus be separated from Zygophylloideae (Zygophyllaceae, Takhtajan. 1987) anda new subfamily-Tetraenoideae be set up for it. A key to subfamilies of Zygophyllaceae(sen. str.) is provided. The systematic position of Tetraena Maxim. is: Rutales-Zygophyllaceae-Tetraenoideae-Tetraena. 相似文献
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蚕豆花粉母细胞染色体畸变同染色质胞间转移的关系 总被引:3,自引:0,他引:3
采用压碎、石蜡切片及植物染色体分带技术观察蚕豆花粉母细胞减数分裂过程发现:1.蚕豆花粉母细胞减数分裂的凝线期也出现染色质胞间转移现象;2.在8.08%的花粉母细胞内,染色体偏离正常的数目(n=6);3.染色体结构也有显著改变,其中包括染色体断裂、桥和长度的增减;4.出现双核和无核的花粉母细胞。大量证据表明,这些畸变现象同凝线期的染色质胞间转移有关。 相似文献
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洪德元 《植物分类与资源学报》2014,36(3):301-302
Pampanini于1910年发表了桔梗科采自湖北西部的一个新种Codonopsis draco。此后100年无人提起它。最近作者在进行党参属及其近缘类群的专著研究中发现它就是1984年发表的刺萼参Echinocodon lobophyllus DY. Hong, 也采自湖北西部。本文作了新组合。刺萼参在湖北郧西的分布点已经消失,至今仅知道陕西东南部两个地点有少量植株,可见刺萼参已处于濒危状态。因为它是单种属,对其保护应予特别关注。 相似文献
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Fu De-Zhi 《植物分类学报:英文版》1988,26(4):249-264
The genus Dichocarpum was established by W. T. Wang and Hsiao in 1964, whodivided the genus into 2 sections: Sect. Dichocarpum including 10 species distributed on themainland of E. Asia, and Sect. Hutchinsonia including 9 species native to Japan. M. Tamuraand L. A. Lauener made a revision of the genus in 1968, who divided the genus into 4 sections, three for the species of the mainland of E. Asia, including 3 series and 10 species, andthe other for the species of Japan, including 2 subsections, 3 series and 9 species. In the present paper, the genus is divided into 2 sections and 6 series, including 15 species and 3 varieties, and a putative phylogeny of the genus is proposed. The genus may be close to the genusAsteropyrum, and these two genera are rather specialized in Thalictroides (Ranunculaceae),because they have three very similar characters: the petal with a long claw, the stephanocolpatepollen and the chromosome morphology. The genus has 2n=24, 35(36?), which indicates thatits basic number is X=6, and the species on the mainland of E. Asia (Sect. Dichocarpum)may well be paleotetraploids, whereas those in Japan (sect. Hutchinsonia) are paleohexaploids. Most of the advanced species are distributed in Japan and the most primitive ones inChina and the Himalayas, the distribution pattern seggests that the Japanese members of this genus might have immigrated from China in the Tertiary, and differentiated and evolvedthere. The putative phylogeny of the genus is shown in Fig. 2 (at series level) 相似文献
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近年来,随着水产经济动物遗传育种研究的迅速发展.对染色体制备技术的要求越来越高。十足类甲壳动物染色体的研究开展较早,但进展却相当缓慢,自一百多年前,Carnoy首次报道了褐虾和滨蟹的染色体,迄今为止已研究过的种类仅约70多种。其主要原因在于其细胞有丝分裂中期染色体形状小,不超过4um,且数目庞大,染色体标本制备和分析都较困难,仍然仅限于染色体数目统计水平。淡水虾类染色体材料与方法的研究极为稀少, 相似文献