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71.
Nearly 32 species of Angelica occur in China, taking up one third of total species
number of the genus in the world, with 12 species in Sichuan. In the present paper karyotypes
of 8 species from Sichuan are first reported with x = 11. The parameters of chromosomes of 8
species are given in Table 1 and the karyotypes are shown in Plate 1, 2. The karyotype formulae are as follows: A. valida Diels K(2n) =22=20m+2sm (Wulong Xian, alt. 1900m); A.
dielsii Boiss. K(2n) =22= 18m+2smsat+2sm (Songpan Xian, alt. 3000m); A. laxifoliata Diels
has 2 kinds of karyotypes in 3 populations: K(2n) =22= 18m+4sm (Hanyuan Xian, alt.
1900m) and K(2n) =22= 16m+6sm (Songpan Xian, alt. 2500m and Baoji in Shaanxi, alt. =
1500m); A. setchuensis Diels K (2n) = 22 = 16m+2smsat+4sm (Songpan Xian, alt. 2800m); A.
maowenensis Yuan et Shan K(2n) =22= 16m+ 6sm (Songpan Xian, alt. 2800); A.
chinghaiensis Shan ex K.T.Fu K (2n) = 4x= 44 = 36m+8sm (Songpan Xian, alt. 3500m); A.
Sinensis (Oliv.)Diels K(2n) =22= 14M+8sm (Songpan Xian, alt. 2900m); A. omeiensis
Yuan et Shan K (2n) = 22 = 10m+2sm+ 10st (Mt. Omei, alt. 2100m). The karyotypes of A.
valida and 2 populations of A. laxifoliata belong to “1A” and those of one population of A.
laxifoliata and the rest 6 species “2A”.
By analysing the correlation between the karyotypic symmetry and vertical distribution
of A. laxifoliata and A. chinghaiensis, it is considered that as altitude rises, the karyotypic
asymmetry and ploidy increases.
Comparing with the karyotypes of other species distributed in Northeastern China
and Japan previously reported, the karyotype of A. valida with oblong-ovoid fruits and
1-2-pinnate leaves is most primitive and that of A. omeiensis with nearly rounded fruits
and 3-ternate-pinnate leaves is most advanced in Angelica. Based on the fact that many
species including the most primitive and the most advanced species are concentrated in
Sichuan, it may be suggested that the center of origin and diversity of Angelica be inSichuan characterized. 相似文献
72.
The common calluses derived from roots of Angelica sinensis were treated with phytohormones and different kinds of organic adjuvants with various concentrations to induce embryogenic callus. The phytohormones obviously affected embryogenic callus induction and the process of globular, heartshaped, torpedo and cotyledon stages. They could emerge from both inside and surface of calluses. In the developmental process, the embryoid still kept in contact with the base of callus from which it arose. 相似文献
73.
Z-Ligustilide was separated and purified from the traditional Chinese medicinal plant Angelica sinensis by high-speed counter-current chromatography (HSCCC). Analytical HSCCC was first used for the systematic selection of the two-phase solvent system. Preparative HSCCC separation was performed with a two-phase solvent system composed of petroleum ether (60-90 degrees C)-ethanol-water at an optimum volume ratio of 10:17:10 (v/v). A total of 38 mg Z-ligustilide at 98.8% purity was obtained in one step from 200 mg crude extract as determined by HPLC analysis. The structure of the target compound was identified by electron impact ionisation mass spectrometry. 相似文献
74.
75.
当归不同生长时期根际丛枝真菌分布及土壤养分和酶活性的动态变化 总被引:2,自引:0,他引:2
【目的】探讨当归不同生长时期丛枝菌根真菌(Arbuscular mycorrhizal fungi,AMF)的分布及土壤养分和土壤酶活的变化,以期了解当归不同生长时期AMF与土壤养分和土壤酶活的关系,为AMF在当归种植的应用提供理论依据。【方法】在当归不同生长时期分别采集根际土壤样品,测定其土壤养分、土壤酶活、AMF孢子密度和球囊霉素等因子,分析当归不同生长时期根际土壤AMF孢子密度、土壤养分和土壤酶活等指标的动态变化和相关性。【结果】随着当归生育期的完成,根际土壤AMF孢子密度先降低后持续升高;易提取球囊霉素(Easily extractable glomalin,EEG)和总球囊霉素(Total glomalin,TG)平稳增加,而且EET与TG和脲酶活性呈显著正相关(P0.01),EET和TG与根际土壤有机质和全氮含量以及酸性和中性磷酸酶活性均显著正相关(P0.05);根际土壤有机质和全氮表现为增加的总趋势;有效磷含量呈现为生长前期保持不变、中期显著降低、后期逐渐升高的趋势,而有效钾含量先逐渐增加,生长中后期显著降低的趋势;根际土壤酸性和中性磷酸酶活性均呈现逐渐增加趋势,而脲酶活性表现为生长前期逐渐增加,中后期显著降低;p H值在当归不同生长时期有所波动。相关性分析结果表明,AMF孢子密度与土壤酸性磷酸酶酶活性呈显著正相关,而酸性磷酸酶酶活性与根际土壤全氮、有机质、易提取球囊霉素和总球囊霉素呈显著正相关,与有效磷和有效钾含量呈显著负相关,表明AMF对根际土壤养分和酶活性具有一定的调节作用;主成分分析结果表明,不同生长时期是影响当归根际土壤理化指标的主要因素。【结论】AMF孢子密度在当归根际的动态变化一定程度上反映出了AMF分泌球囊霉素的能力,以及球囊霉素对增加根际土壤碳氮储存的贡献,同时表明球囊霉素影响了当归根际土壤酶活性和其它养分的代谢循环,对改良土壤和促进当归生长发挥重要的作用。 相似文献
76.
当归属及近缘小属的核型演化及地理分布研究 总被引:9,自引:2,他引:9
本文报道了当归属Angelica及3个近缘小属12种植物的核型,其中10种为首次报道。带岭当归A.dailingensis 2n=22=20m+2sm(SAT);丽江当属A.likiangensis 2n=22=18m+4sm; 青海当归A.nitida 2n=22=14m+4sm+4sm(SAT);林当归A.silvestris 2n=22=16m+4sm(SAT)+2st(SAT);紫花前胡A.decursiva 2n=22=16m+4sm+2sm(SAT);秦岭当归A.tsinlingensis 2n=22=18m+4sm; 阿坝当归A.apaensis 2n=22=14m+6sm+2st(SAT);隆萼当归A.oncosepala2n=4x=44=28m+12sm+4st,三小叶当归A.ternata 2n=22=10m+8sm(SAT)+4st(SAT);柳叶芹Czernaevialaevigata 2n=22=14m+6sm+2sm(SAT);短茎古当归Archangelica brevicaulis 2n=22=8m+2m(SAT)+4sm+4sm(SAT)+4st;高山芹Coelopleurum saxatile 2n=28=12m+6sm+10st。除带岭当归核型为1A型和高山芹为2B型外,其余种类均为2A型。根据染色体长度比和平均臂比绘制了本次和我们过去已报道的当归属及近缘属23种植物的核型散点图。据核型类型和近端着丝点的有无,把当归属20个种的核型分3组。并结合外部形态、花粉类型和地理分布,探讨了各近缘属的系统演化关系。 相似文献
77.
Hanno Schaefer Mónica Moura M. Graciete Belo Maciel Luís Silva Fred J. Rumsey Mark A. Carine 《Journal of Biogeography》2011,38(7):1345-1355
Aim Speciation processes on islands are still poorly understood. Previous studies based on the analysis of distribution data from checklists found that the flora of the Azores archipelago differs from other island floras in the exceptionally low number of radiations and the low number of single‐island endemics. The general mechanism(s) responsible for these apparently unique patterns remained unclear. One possible explanation for the distinctiveness of the Azorean endemic flora is the lack of a consistent and critical taxonomic framework for the floras of the Atlantic archipelagos. In this study, molecular variation within a range of Azorean endemic plant lineages was analysed to determine whether inadequacies in the current taxonomy of endemics might be an explanation for the unusual diversity patterns observed in the endemic flora of the Azores. Location Azores archipelago. Method Sixty‐nine populations of eight endemic species or subspecies belonging to five genetic lineages were sampled from all Azorean islands but one. Nuclear and plastid DNA regions were sequenced, and relationships among internal transcribed spacer (ITS) region ribotypes established using statistical parsimony. Results Molecular diversity patterns differ from current taxonomic groupings, with all lineages comprising previously overlooked genetic entities. Main conclusions Recognition as distinct taxa of the genetically distinct entities discovered in this study would drastically change the diversity patterns and make them more similar to those of other Atlantic archipelagos. The results serve to highlight that current knowledge of endemic diversity on oceanic islands may be far from complete, even in relatively well‐known groups such as angiosperms. This limitation is rarely considered in macroecological and evolutionary studies that make use of data from taxonomic checklists to draw inferences about oceanic island biogeographic processes. 相似文献
78.
中国独活属和当归属系统演化及区系地理的温带性 总被引:1,自引:0,他引:1
中国复杂的地质地貌和古老的地史,尤其在横断山区和四川地区,是伞形科独活属及其近邻属的演化和分化中心,区系古老且温带性质明显.从核型和花粉方面分析,独活属和当归属的系统演化表现出比较密切的亲缘关系. 相似文献
79.
当归叶片光合参数日变化及其与环境因子的关系 总被引:8,自引:2,他引:6
在当归根茎膨大期,利用CI-310便携式光合仪,田间活体测定了当归的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、胞间CO2浓度(Ci)等光合生理生态因子,以及光合有效辐射(PAR)、田间CO2浓度(Ca)、相对湿度(RH)、大气温度(Ta)、叶温(TL)等环境因子的日变化。结果表明,当归Pn日变化曲线为"双峰"型,最高峰出现在10:00左右,次高峰出现在16:00左右,午间有明显的"午休"现象,气孔因素是导致其"午休"的主要原因。Tr、Gs和Ci的日变化曲线均为"双峰"型,最高峰出现在10:00,次高峰出现在17:00。当归叶片净光合速率随环境因子日变化最优逐步多元回归方程为yPn=14.3108 0.0076xPAR-0.5271xTL(R2=0.6601,P<0.05),TL和PAR是对光合速率直接影响最大的生态因子,而Ca、RH和Ta主要是通过TL而间接影响光合速率的变化。 相似文献