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81.
小偃麦原生质体培养及植株再生 总被引:3,自引:0,他引:3
硬粒小麦(Triticum durum Desf.AABB)和中间偃麦革[Elytrigia intermedium(Host)Nevski BBEEFF]的杂种 F_1——小偃麦的幼穗诱导的胚性愈伤组织继代培养近两年后,转入修改的 MS 液体培养基建成胚性细胞悬浮系。从此悬浮系分离的原生质体在修改的 KM_(8p)培养基中培养48小时后出现第一次分裂。15天后,在液体浅层培养条件下的细胞分裂频率为2%;而用1.2%琼脂糖固化进行固体平板培养时,细胞的分裂频率则为12.14%。20—30天后,添加渗透压降低的原生质体培养液。当从原生质体再生的愈伤组织长至2—4mm 大小时,逐步转至生长及分化培养基上再生出完整植株。 相似文献
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85.
描述了爵床科孩儿草属的一个新组-密花孩儿草组Rungia sect.Stoloniferoe C.M.Gao&Y.F.Deng。本新组花序不偏向一侧,苞片均能育,同形。 相似文献
86.
为选育金花茶优良品种,以7种金花茶组(Camellia sect. Chrysantha)植物成熟叶片为试材,对其总黄酮、茶多酚、总多糖、总皂苷、总氨基酸及维生素E等6种营养物质及K、Ca、Na、Fe、Mn、Zn、Se等7种矿质元素含量进行测定比较,通过聚类分析,考查不同金花茶组植物叶片间存在的药用价值差异。结果表明,7种金花茶组植物叶片的营养成分含量丰富且存在显著差异:凹脉金花茶(Camellia impressinervis)的茶多酚含量最高,达7.13%;东兴金花茶(C. tunghinensis)的总皂苷含量最高,达0.41 g·100 g-1;柠檬金花茶(C. limonia)的总黄酮含量最高,达671.67 mg·100 g-1。矿质元素方面各种类均呈现高钾低钠的特征,凹脉金花茶、柠檬金花茶和小果金花茶(C. nitidissima var. microcarpa)K含量高于Ca,且各品种中均检测出Se元素。综合结果表明,凹脉金花茶叶片中茶多酚、总多糖、总氨基酸等各类营养成分含量相对较高,具有潜在的研究与开发价值。 相似文献
87.
芍药属牡丹组(Paeonia sect. Moutan)种间关系的分子证据:GPAT基因的PCR-RFLP和序列分析 总被引:18,自引:0,他引:18
为了探讨芍药属牡丹组Paeonia sect. Moutan的种间关系,对采自15个野生居群,代表牡丹组全部8个野生种的15份材料的GPAT 基因片段(外显子5和6之间2 kb的内含子)进行了PCR-RFLP分析,并对代表牡丹组全部8个野生种的9份材料进行了测序。 根据12个限制性内切酶的PCR-RFLP数据,使用Network 3.0计算机程序的RM (reduced-median)法建立了牡丹组种间亲缘关系网络树。同时根据8个种9份材料的GPAT基因片段序列,利用PAUP*4.0计算机程序建立了牡丹组GPAT基因的最大简约(MP)树和邻接(NJ)树。结果获得了具有很高自展值支持、分辨良好的牡丹组种间关系(GPAT基因)树。最重要的是,该基因树所显示的牡丹组种间关系与根据形态学证据提出的牡丹组的种间关系基本吻合,并得到其他研究证据的支持。根据这一结果,对牡丹组的种间关系进行了详细的讨论。 相似文献
88.
Rui Yuan Xiaolei Ma Zhuoxin Zhang Richard J. Gornall Yongcui Wang Shilong Chen Qingbo Gao 《Ecology and evolution》2023,13(1):e9694
Comprising ca. 200 species, Saxifraga sect. Ciliatae is the most species-rich section of Saxifraga s.str., whose center of diversity is in the Tibeto-Himalayan region. The infra-sectional classification of sect. Ciliatae is still in debate due to the high level of species richness, as well as remarkable variations of habitat, morphology, physiology and life cycles. Subdivisions of this section proposed in various taxonomic systems have not been adequately tested in previous phylogenetic studies, partly due to low taxonomic sampling density, but also to the use of few DNA markers. In order to achieve a more robust infra-sectional classification of sect. Ciliatae, complete chloroplast genomes of 94 taxa from this section were analyzed, of which 93 were newly sequenced, assembled and annotated. The length of the 94 plastomes of sect. Ciliatae taxa range from 143,479 to 159,938 bp, encoding 75 to 79 unique protein-coding genes (PCGs). Analyses of the 94 plastomes revealed high conservation in structural organization, gene arrangement, and gene content. Gene loss and changes of IR boundaries were detected but in extremely low frequency. The molecular phylogenetic tree from concatenated PCGs and complete chloroplast genome sequences exhibited high resolution and support values and confirms that sect. Ciliatae is monophyletic. Three well-supported clades were revealed within the section that agree relatively well with the subsectional taxonomy of Gornall (1987), but some minor modifications should be made. Firstly, the monotypic subsection Cinerascentes should be abandoned and its constituent species, S. cinerascens, assigned to subsect. Gemmiparae. Secondly, subsections Rosulares and Serpyllifoliae should be merged and become subsect. Rosulares. Section Ciliatae thus comprises: subsect. Hirculoideae Engl. & Irmsch.; subsect. Rosulares Gornall; subsect. Gemmiparae Engl. & Irmsch.; subsect. Flagellares (C. B. Clarke) Engl. & Irmsch. and subsect. Hemisphaericae (Engl. & Irmsch.) Gornall. 相似文献
89.
Twenty species of shrubbyOxalis species native in South America were arranged in six groups according to their karyotype similarities. The first group includes more than half of the species studied, all with 2n = 12 relatively small metacentric chromosomes. The rest of the species from the other groups has different basic chromosome numbers, and exhibits various degrees of chromosome asymmetry and size increase. These latter groups apparently have specialized to habitats with low light intensity such as the forest undergrowth in contrast to the frist group whose members live in open areas (i.e., grasslands, savannas etc.). 相似文献
90.
A survey is made of the occurrence, nature and frequency of satellited chromosomes in the agamospermous genusTaraxacum. Species belonging to the 10 sections thought to be most primitive in the genus lack satellited chromosomes. In most other sections, a characteristic satellited chromosome is seen with a large euchromatic region distal to the presumed nucleolar oraniser region (NOR). In sections of a precursor type, there is always one chromosome of this Taraxacum type per haploid genome. In sections thought to be of an advanced type the number of such satellited chromosomes is very unstable, sometimes even within the same tissue. In sectionHamata, two such satellited chromosomes are invariably found in triploids. This finding strongly supports the integrity of this section, suggests that the species of the section are monophyletic, and have evolved from a single ancestor subsequent to the occurrence of obligate agamospermy. In three sections of the genus, satellited chromosomes of the conventional type with a very small distal euchromatic region distal to the NOR are reported for the first time in the genus. 相似文献