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1.
广义的紫菀属(Asters.l.)曾是个大包大揽的类群,产于北美和欧亚大陆.Nesom主要根据瘦果的形态和细胞学性状对Asters.l.进行了评价,将北美紫菀类植物从Aster中独立出去,使Aster成为欧亚特有类群.但是,在欧亚各国对Aster有定为一属和分为十多个属等不同的分类学处理,分歧较大.狭义紫菀属(Asters.s.)与从Asters.l.中分出的各属之间的系统学关系,以及后者中某些属与北美紫菀类和紫菀族其他亚族间的系统学关系,都存在很大疑问.过去一直认为北美是Aster的发源地,现在欧亚Asters.l.的起源与演化需要重新研究,而青藏高原是探讨Asters.l.物种多样性形成的关键地区.DNA尤其是DNA序列资料在研究Asters.l.的系统发育和分类上将发挥关键作用.  相似文献   

2.
Aster ageratoides var. pendulus W. P. Li & G. X. Chen, a new variety of Aster (Asteraceae) from Shimen County, northwestern Hunan, China, is described. The variety is similar to A. ageratoides var. laticorymbus (Vant.) Hand.-Mazz., from which it differs by having pendent stem, basal leaves and lower stem leaves purple beneath, stem leaves linear, hispid above, and broader phyllaries. The new variety is also possibly similar to A. ageratoides var. micranthus Ling in the linear leaves and white ligules, but differs by having the phyllaries green at apex, 1.25–1.75 mm wide, and the obvious creeping underground rhizomes.  相似文献   

3.
菊科紫菀属横斜系(Asterseries Hersileoides Ling)特产于中国,含横斜紫菀(Aster hersileoides Schneid.)和亮叶紫菀(A.nitidus Chang)2个狭域分布种。细胞学研究表明,横斜紫菀和亮叶紫菀均为二倍体,染色体较小,长度在1.64~2.8μm之间,核型公式为2n=2x=18=16m+2sm,属1A类型。横斜紫菀和亮叶紫菀的染色体数目和核型为首次报道。  相似文献   

4.
湖南紫菀属(菊科)一新变种--垂茎三脉紫菀   总被引:1,自引:0,他引:1  
报道了湖南紫菀属Aster一新变种——垂茎三脉紫菀A.ageratoides var.pendulus W.P.Li&G X.Chen。新变种与宽伞三蔓脉紫菀A.ageratoides var.laticorymbus(Vant.)Hand.-Mazz.最为接近,但以如下特征与之相区别:茎下垂,基生叶和茎下部叶背面常为紫色,茎生叶常条形,叶上面被糙毛,总苞片较宽。新变种因叶常条形和舌状花白色而与小花三脉紫菀A.ageratoides var.microanthus Ling相似,但总苞片顶端旱绿色,1.25-1.75mm宽,具明显横走地下茎而不同。  相似文献   

5.
Eight polymorphic microsatellites were developed in the perennial herbaceous Aster amellus L. (Asteraceae) and characterized on three populations from France and Switzerland. The number of alleles ranged between four and 30 depending on the locus, and the mean number of effective alleles was 5.8. The average gene diversity equalled 0.744 (range: 0.419–0.957) and the overall differentiation was found significant (θ = 0.092, P < 0.01). Three loci displayed significant heterozygote deficiencies, which might indicate the presence of null alleles. Amplifications were detected on eight loci in Aster alpinus L.  相似文献   

6.
产自湖北神农架的狭叶三脉紫菀Aster ageratoides var. gerlachii (Hance) Chang一直被各种文献和有关标本馆误定为小花三脉紫菀A. ageratoides var. micranthus Ling。我们对二者进行了野外采集和形态学、细胞学的比较研究,分析了导致错误鉴定的原因,重新确定了二者的界限。小花三脉紫菀无横走地下茎,这一性状具有重要的分类学价值。核型研究发现,小花三脉紫菀为二倍体,2n=2x=18=18m,核型属1A型;狭叶三脉紫菀则是四倍体,2n=4x=36=32m+4sm (2SAT),核型属2A型。二变种的染色体数目、核型均为首次报道。狭叶三脉紫菀在湖北为新分布记录。  相似文献   

7.
紫菀中肽类成分研究进展   总被引:1,自引:0,他引:1  
环肽astins是紫菀比较有特色的一类化学成分,至今此类型环肽只在该种中发现。其结构新颖,是紫菀抗肿瘤活性的主要成分。在植物分类学及抗肿瘤新药开发上都具有较高的研究开发价值。本文以紫菀astins为主要对象,对其化学结构、生物活性、构效关系方面的研究进行了综述。  相似文献   

8.
A new yellows disease of watercress (Nasturtium officinale) in Hawaii has symptoms of reduced leaf size, leaf yellowing and crinkling, and occasionally witches’ brooms. This disease is found on all watercress farms on Oahu but has not yet been found on other Hawaiian islands. Watercress plants were tested for phytoplasma infection by polymerase chain reaction assays using phytoplasma‐specific primers. Amplicons of the expected sizes were produced from all symptomatic plants but not from healthy plants raised from seed. Phylogenetic analysis of the 16S rRNA gene indicated that watercress yellows was caused by a phytoplasma in the aster yellows group, with sequence similarity to onion yellows from Japan. Six weed species collected from the vicinity of affected watercress farms, Amaranth sp., Eclipta prostrata, Emilia sonchifolia, Plantago major, Myriophyllum aquaticum and Sonchus oleraceus, were also determined to be hosts of this phytoplasma. Leafhoppers, identified as Macrosteles sp. (Hemiptera, Cicadellidae), collected from symptomatic watercress transmitted this phytoplasma to watercress, plantain and lettuce (Lactuca sativa) in greenhouse experiments.  相似文献   

9.
利用溶剂萃取,大孔树脂、硅胶和聚酰胺的色谱法,对缘毛紫菀的正丁醇萃取物的化学成分进行了研究,从中分离得到4个三萜皂苷,经1H-NMR、13C-NMR等现代波谱技术及化学方法分别鉴定为续断皂苷B(1)、臭瓜皂苷A(2)、三褶脉紫菀皂苷A(3)和东风菜皂苷A4(4)。化合物1为首次从该属植物中得到,化合物2、3和4为首次从缘毛紫菀中得到。  相似文献   

10.
A new monoterpene glycoside named shio nc, side C was isolated from the root of Aster tataricus L. f. (Compositae). lts structure was elucidaied as L-endo-camphanol-8-O-3,5-isopropylidene-β-D-apiofuranosyl- (1-6) -β-glucopyranoside ( Ⅰ ) by means of spectral and chemical evidence.  相似文献   

11.
三峡库区川鄂紫菀(菊科)的形态学和细胞学研究   总被引:5,自引:1,他引:4  
对川鄂紫菀(Aster moupinensis (Franch.)Hand.-Mazz.)秭归居群进行了形态学和细胞学研究。形态学研究表明,川鄂紫菀存在居群间分化,但不足以划分变种。发现了一些被以前研究者忽视的重要性状,首次报道了川鄂紫菀的染色体数目和核型。其核型公式为2n=2x=18m。  相似文献   

12.
钻形紫菀开花期种群构件的生物量分配   总被引:6,自引:1,他引:5  
在野外用样方法,选取60株钻形紫菀(Aster subulatus Michx.)开花植株,进行根、茎、叶及花等构件的生物量及其物质分配关系的研究.结果表明:钻形紫菀开花期构件生物量为茎>花>根>叶,其变异系数分别为57.15%、64.66%、57.65%和55.2%,具有较大表型可塑性;在各构件物质分配变异系数中,花生物量分配的变异系数相对较大,说明其调节生殖分配的能力较强;植株高度与各构件生物量呈显著的正相关性,随着各构件生物量的增加均呈幂函数形式增加;花生物量分配与总生物量呈显著的正相关性,其余构件生物量分配均与总生物量及花生物量分配呈负相关性,物质分配由营养构件、支持构件、光合构件向生殖构件转移.反映出钻形紫菀具有自我调节生长力的分配策略,对异质环境具有较强适应能力.  相似文献   

13.
紫菀中一个新单萜甙的结构   总被引:1,自引:0,他引:1  
Nagao等(1988)报道了紫菀(Aster tataricus L.f)中两个新单萜甙的结构。本文报道另一新单萜甙(1)的结构(图 1)。 4.5kg紫菀根的70%乙醇提取物,依次用苯、乙酸乙酯萃取。乙酸乙酯萃取物(40g)上硅胶柱。氯仿-甲醇(4:1)洗出物再经硅胶柱及制备薄层层析,得无色针状结晶(1)120mg。结晶(1)mp 68—70℃,Molish  相似文献   

14.
紫菀种质资源的评价与分析   总被引:1,自引:0,他引:1  
紫菀具有重要的药用价值,为我国传统常用中药材,开展紫菀种质资源的鉴定和评价,是提高紫菀产量和品质的前提和基础。通过田间性状调查和室内分析,对取自河北安国和安徽亳州的44份紫菀种质进行性状和品质评价,并对种质遗传多样性进行聚类分析。结果显示:影响种苗质量三因素的变异程度为茎毛数>茎粗>芽距,室内发芽试验结果同样显示种苗的茎毛数对发芽率的影响最大,芽距最小;不同种源紫菀间的叶宽差异不明显,不同种源紫菀间的其他性状如叶长、株高和生长势等性状都表现不同程度的变化,不同种源间的干重和紫菀酮含量差异明显,都表现出极显著水平;不同种源间叶长、叶宽和株高与生长势呈显著的正相关,干重和生长势呈显著的负相关性,紫菀的干重和紫菀酮的含量呈负相关性;根据相似系数进行的聚类结果表现出明显的地域性,该研究明确了不同地区的紫菀为适应当地的生态环境,在遗传上发生了适应性的分化、变异,这为优良品种的选择和选育提供了有利的理论依据。  相似文献   

15.
紫菀根中矿质元素及氨基酸质量分数的测定   总被引:2,自引:0,他引:2  
采用原子吸收分光光度法和高效液相色谱法测定了紫菀根中的矿质元素和游离氨基酸的质量分数。矿质元素Cu、Zn、Fe、Mg、Ca、Mo、Mn、Se的质量分数分别为 42 .89、5 8.14、92 0 .93、2 5 48.2 5、392 5 .43、0 .6 5、5 2 .18mg·Kg- 1 、<0 .0 0 0 5mg·Kg- 1 ;氨基酸 :天门冬氨酸、谷氨酸、甘氨酸、苏氨酸、组氨酸 +精氨酸、丙氨酸、蛋氨酸、缬氨酸、苯丙氨酸、异亮氨酸、亮氨酸、赖氨酸的质量分数分别为 2 6、17、40、36、190、36、37、80、8.7、4.5、13、41mg·Kg- 1 。  相似文献   

16.
Abstract The ‘tidal salt marsh’ ecotype of the halophyte Aster tripolium L. was grown in a nutrient solution with either a continuous or an intermittent NO3? supply with either Cl? or SO42? as the alternative anion. With increasing periods of NO3? supply per week the rate of the dry weight increment increased. When NO3? was supplied for longer than 48 h per week, the dry weight and the organic-N content in the shoots hardly increased, whereas the NO3? content in shoots and roots increased further. With alternated supply of a nutrient solution containing NO3? with one containing Cl?, the internal NO3? content in the shoot was lower than in shoots grown in solutions in which NO3? alternated with SO42?. It is concluded, that NO3? does not have a specific function in osmoregulation.  相似文献   

17.
Abstract: Genotypic and environmental variation in Aster tripolium L. was studied in common garden experiments and in transplantation experiments in different saltmarsh sites along the estuarine gradient of the Westerschelde and along the elevation gradient of individual saltmarshes. Analysis of the variation in a number of morphologic characters of the inflorescences indicated that this variation is both environmentally as well as genetically controlled. Morphologic differences between an Aster tripolium population of a brackish marsh and a number of populations of a saline marsh were unchanged whether the plants were growing in their original habitat or in a transplant habitat. The population from the brackish marsh had smaller inflorescences with ray florets and a predominantly biennial life cycle, in contrast with the populations of the saline marsh, which had larger inflorescences usually without or with a few ray florets and showed a tendency to a perennial life cycle. We concluded that the variation between the populations of the saline and the brackish marsh is mainly genetically controlled, while the variation within the saline marsh is mainly environmentally controlled.  相似文献   

18.
微糙三脉紫菀的细胞地理学研究   总被引:1,自引:0,他引:1  
三脉紫菀多倍体复合体一直被认为是一个困难的类群.但是,作为该复合体主产地的中国,其分类学研究和细胞学资料十分缺乏.因此,对微糙三脉紫菀9个居群进行了细胞学研究、结果显示,微糙三脉紫菀为四倍体(2n=4x=36),关于微糙三脉紫菀有六倍体的报道应属鉴定错误.微糙三脉紫菀6个居群的核型资料表明,其核型的不对称性具有经度地带性变异的趋势.据此认为,微糙三脉紫菀起源于浙皖山丘西部,然后向西扩散,抵达云贵高原和四川.这一假设得到横走地下茎演化证据的支持.  相似文献   

19.
Abstract A study of the growth of the maritime halophyte Aster tripolium L. has been carried out over a range of salinity treatments. The regression approach to growth analysis using frequent small harvests has been used to allow ‘continuous’ measurement of growth over a period of 36 d. Salinity was applied with the major ions present in ratios typical of those found in seawater. Growth was inhibited in terms of both dry weight production and leaf expansion at salinity levels equivalent to 0.625 strength sea water (full culture solution 300) and above, with the greatest effect being seen in terms of leaf area. Aster tripolium did not show increased succulence at high salinity, leaf fresh weight to dry weight ratio in fact declined, whilst leaf fresh weight per unit area remained constant. It should be noted that the plants exhibit low growth rates due to the low light intensity used.  相似文献   

20.
缘毛紫菀化学成分研究   总被引:2,自引:0,他引:2  
我们从菊科植物缘毛紫菀的甲醇提取物的氯仿部分中分离得到6个化合物,并运用红外光谱、质谱、核磁共振等方法鉴定了它们的结构。它们分别为:β—谷甾醇,β—胡萝卜甙,芹菜素,18,19—二羟基—5α,10β—新克罗烷—二烯—丁烯羟酸内酯,橙皮甙,18—O-β—D-吡喃葡萄糖—19-羟基-新克罗烷—二烯—丁烯羟酸内酯。  相似文献   

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