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1.
宝铎草和长穗开口箭的核型   总被引:4,自引:0,他引:4  
杨亲二   《广西植物》1995,15(2):158-162
本文对湖南产的宝锋草(DisporumsessileD.Don)和广西产的长穗开口箭(TupistralongispicgY.WanetX.H.Lu)的核型作了分析。前者的核型公式为2n=14=4g+10sm(2sat),核型类型属于3A;后者的核型公式为2n=38=24m+6sin+8st.核型具有明显的二型性,属于2C型。此外还讨论了宝锋草的核型变异以及开口箭属和蜘蛛抱蛋属(Aspidistra)的关系。  相似文献   
2.
从弯蕊开口箭(Tupistra wattii Hook. f.)的新鲜根茎中分离出2个新的多羟基甾体皂甙元,分别命名为弯蕊皂甙元B (wattigenin B) (1) 和弯蕊皂甙元C (wattigenin C) (2), 同时分离到2个已知的甾体皂甙元--凯替皂甙元kitigenin (3)和铃兰皂甙元B (convallagenin B) (4).通过波谱解析鉴定了这4个皂甙元的结构,并测定了它们在体外对肿瘤细胞K562和A2780a的细胞毒活性.化合物1~4为首次从该种植物中分离得到.  相似文献   
3.
A species of the genus Tupistra,T.pingbianensis J.L.Huang et X.Z.Liu,is described as new,and its karyotype and pollen morphology are reported. The bimodal karyotype of this species is formulated as 2n=38=14m+10sm+8st+6t,and pollen grains are spheroidal,inaperturate,with rugulate exine sculpture.Based on its floral structure,karyotype and pollen morphology,T.pingbianensis J.L.Huang et X.Z.Liu is considered phylogenetically closely related to T.fungilliformis Wang et Liang.Whether the repense rhizome,solitary leaves of T.pingbianensis J.L.Huang et X.Z.Liu indicate a close relationship between the genus Tupistra and the genus Aspidistra needs further studies.  相似文献   
4.
心不甘中甾体皂甙元的分离和结构鉴定(3)   总被引:5,自引:0,他引:5  
本文报告心不甘(Tupistra aurantiaca Wall et Backer)根的粗甙经盐酸水解后的总甙元中分离的甙元E和F的结构鉴定。甙元F经鉴定为△~(25(27))-pentrogenin(2)。甙元E(ranmo-genin D)为新化合物,其结构经IR、MS、~1H NMR和~(13)C NMR谱分析推定如(1)所示。  相似文献   
5.
心不甘中甾体皂甙元的分离和结构鉴定(2)   总被引:2,自引:0,他引:2  
自心不甘(Tupistra aurantiaca Wall et Backer)根的醋酸乙酯萃取物经硅胶柱层析分离除可得到1β、2β、3β、4β、5β、7α-hexahydroxyspirost-25(27)-en-6-one外,还得到7个游离的甾体皂甙元A—G,其中A及B分别为3-epiruscogenin及3-epi-neoruscogenin,F为△~(25(27))-pentrogenin(6)、C、D和E系新化合物,经IR、MS、~1H NMR及~(13)C NMR谱鉴定分别推定为ranmogenin A(3)、B(4)和C(5)(兰茂甙元甲、乙和丙)。  相似文献   
6.
爪哇三七组织培养植株再生   总被引:1,自引:0,他引:1  
本文报道了爪哇三七通过组织培养再生植株的方法。爪哇三七的叶片,叶柄或茎段外植体分别接种于6种分化培养基上,均难以直接分化。在附加1mgL~(12),4-D和0.1mgL~(-1)KT的B_5培养基上的叶片形成无色疏松的愈伤组织转接于MS附加1mgL~(-1)BAP和0.1mg L~(-1)NAA培养基上,5天后开始形成绿色球胚状结构,继而形成不定芽或丛生芽。这些不定芽或丛生芽在锈根培养基中迅速长成根系发达的完整植株。此外,本试验比较了不同浓度及不同组合的激素对爪哇三七外植体的脱分化、再分化的影响。并讨论了此项工作对柑桔裂皮病类病毒(简称CEV)的复制及致病机理研究的意义。  相似文献   
7.
The levels and partitioning of genetic diversity and inbreeding depression were investigated in Tupistra pingbianensis, a narrow endemic of southeast Yunnan, China, characterized by a naturally fragmented distribution due to extreme specialization on a rare habitat type. Here genetic diversity and patterns of genetic variation within and among 11 populations were analyzed using amplified fragment length polymorphism markers with 97 individuals across its whole geographical range. High levels of genetic variation were revealed both at the species level (P_(99)=96.012%; H_t=0.302) and at the population level (P_(99)=51.41%; H_8= 0.224). Strong genetic differentiation among populations was also detected (F_(ST)= 0.2961; θ~Ⅱ= 0.281), which corresponded to results reported for typical animal-pollinated, mixed selfing, and outcrossing plant species. This result was consistent with mating patterns detected by our pollination experiments. The indirect estimate of gene flow based on θ~Ⅱwas low (N_m=0.64). Special habitat and its life history traits might play an important role in shaping the genetic diversity and the genetic structure of this species. A pollination experiment also failed to detect significant inbreeding depression upon F_1 fruit set, seed weight, and germinate rate fitness-traits. As a naturally rare species, T. pingbianensis is not seriously genetically impoverished and likely to have adapted to tolerating a high level of inbreeding early in its history, we propose this species need only periodic monitoring to ensure their continued persistence, but not intervention to remain viable.  相似文献   
8.
通过对黄褐筛菌(Cribraria aurantiaca)和小筛菌(Cribraria microcarpa)的孢囊及囊被进行显微结构观察,为筛菌属黏菌分类提供了图鉴资料。  相似文献   
9.
The levels and partitioning of genetic diversity and inbreeding depression were investigated in Tupistra pingbianensis, a narrow endemic of South-east Yunnan, China, characterized by a naturally fragmented distribution due to extreme specialization on a rare habitat type. Here genetic diversity and patterns of genetic variation within and among 11 populations were analyzed using AFLP markers with 97 individuals across its whole geographical range. High levels of genetic variation were revealed both at the species level (P99 = 96.012%; Ht = 0.302) and at the population level (P99 = 51.41%; Hs = 0.224). Strong genetic differentiation among populations was also detected (FST = 0.2961; ⍬= 0.281), which corresponded to results reported for typical animal-pollinated, mixed selfing and outcrossing plant species. This result was consistent with mating patterns detected by our pollination experiments. The indirect estimate of gene flow based on ⍬ was low (Nm = 0.64). Special habitat and its life history traits may play an important role in shaping the genetic diversity and the genetic structure of this species. A pollination experiment also fail to detect significant inbreeding depression upon F1 fruit set, seed weight and germinate rate fitness-traits. Since naturally rare species T. pingbianensis is not seriously genetically impoverished and likely to have adapted to tolerating a high level of inbreeding early in its history, we propose this species need only periodic monitoring to ensure their continued persistence but not intervention to remain viable.  相似文献   
10.
开口箭属一新种及其核型和花粉形态   总被引:1,自引:0,他引:1  
文章报道了新种屏边开口箭T.pingbianensis J.L.Huang et X.Z.Liu及其核型和花粉形态。屏边开口箭的核型公式为2n=38=14m+lOsm+8st+6t,具明显的二型性,属3C型。花粉粒为球形,无萌发孔沟,外壁具皱块状纹饰。从花结构、核型和花粉形态上看,屏边开口箭和伞柱开口箭T.fungilliformis Wang et Liang亲缘关系近,而且伞柱开口箭比屏边开口箭在一系列特征上都较特化。  相似文献   
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