中华猕猴桃和美味猕猴桃的倍性变异及地理分布研究

根据已有的猕猴桃自然地理分布资料,通过对中华猕猴桃（Actinidia chinensis）和美味猕猴桃（A．deliciosa）野外分布居群的详细调查,利用流式细胞技术对我国西部高原台地向中东部丘陵平原过渡地带6个纯中华猕猴桃、1个纯美味猕猴桃和5个中华／美味猕猴桃同域分布居群共276个个体的倍性进行了检测。结果表明：（1）中华猕猴桃存在二倍体和四倍体,美味猕猴桃存在四倍体、五倍体和六倍体;（2）中华猕猴桃和美昧猕猴桃在经度和纬度的分布上存在显著差异（P〈0．05）,中华猕猴桃在经度上偏东分布而美味猕猴桃偏西,纬度分布上中华猕猴桃偏南而美味猕猴桃偏北;而且不同倍性小种在经、纬度分布上呈现显著差异（P〈0．05）,二倍体、四倍体、六倍体的分布在经度上依次从东到西、纬度上从南到北;（3）中华猕猴桃和美味猕猴桃不同倍性小种的海拔分布存在显著性差异（P〈0．05）,二倍体小种分布海拔最低,四倍体小种次之,六倍体小种海拔分布最高,但通过LSD分析四倍体个体和六倍体个体在海拔分布上不存在显著差异（P〉0．05）。通过对中华／美味猕猴桃这两种具有重要经济价值的果树的倍性变异及地理分布的探讨,提出了猕猴桃倍性小种分布的上述规律并给猕猴桃种质资源收集、评价、创新和可持续利用方面提供了初步的研究基础,尤其是为我国猕猴桃新品种选育提供了基础数据和科学依据。     

稻属三种植物叶片下表皮的形态比较

稻属有20多种,其中3种和其他物种明显不同.Oryza eichingeri被认为在亚洲和非洲间断分布;O. officinalis和O punctata被证明同时含有二倍体和四倍体.为了识别种内微形态差异,利用光镜和扫描电镜,对这3个物种的成熟叶片下表皮进行了观察.结果表明,O. eichingeri的叶脉长细胞乳突形状在种内是不一致的,除了斯里兰卡地理宗具有的瘤状乳突外,乌千达地理宗还具有长条状的乳突;同样,种内多样性也存在于O. officinalis和O.punctata内,特别存在于它们不同倍性的细胞型间.在D officinalis中,四倍体有粒状气孔器外围乳突和脉带表皮毛较少,二倍体细胞型具有三角形拱状排列的气孔器外围乳突和较密集的脉带表皮毛;而在O. punctata中,和四倍体相比,二倍体具有小的长细胞表面乳突和低密度分布的气孔.这些稳定的差异为3种植物的种内鉴定和分类修订提供了新的证据.     

Doubled haploid production in Flax (Linum usitatissimum L.)

There is a requirement of haploid and double haploid material and homozygous lines for cell culture studies and breeding in flax. Anther culture is currently the most successful method producing doubled haploid lines in flax. Recently, ovary culture was also described as a good source of doubled haploids. In this review we focus on tissue and plants regeneration using anther culture, and cultivation of ovaries containing unfertilized ovules. The effect of genotype, physiological status of donor plants, donor material pre-treatment and cultivation conditions for flax anthers and ovaries is discussed here. The process of plant regeneration from anther and ovary derived calli is also in the focus of this review. Attention is paid to the ploidy level of regenerated tissue and to the use of molecular markers for determining of gametic origin of flax plants derived from anther and ovary cultures. Finally, some future prospects on the use of doubled haploids in flax biotechnology are outlined here.     

Proteomic analysis from haploid and diploid embryos of Quercus suber L. identifies qualitative and quantitative differential expression patterns

Quercus suber L. is a Mediterranean forest species with ecological, social and economic value. Clonal propagation of Q. suber elite trees has been successfully obtained from in vitro‐derived somatic and gametic embryos. These clonal lines play a main role in breeding and genetic studies of Q. suber. To aid in unravelling diverse genetic and biological unknowns, a proteomic approach is proposed. The proteomic analysis of Q. suber somatic and gametic in vitro culture‐derived embryos, based on DIGE and MALDI‐MS, has produced for the first time proteomic data on this species. Seventeen differentially expressed proteins have been identified which display significantly altered levels between gametic and somatic embryos. These proteins are involved in a variety of cellular processes, most of which had been neither previously associated with embryo development nor identified in the genus Quercus. Some of these proteins are involved in stress and pollen development and others play a role in the metabolism of tannins and phenylpropanoids, which represent two of the major pathways for the synthesis of cork chemical components. Furthermore, the augmented expression levels found for specific proteins are probably related to the homozygous state of a doubled‐haploid sample. Proteins involved in synthesis of cork components can be detected at such early stages of development, showing the potential of the method to be useful in searching for biomarkers related to cork quality.     

17种金线鲃核DNA含量及倍性的研究

采用血涂片、Feulgen染色和显微分光光度技术 ,测定了金线属 (Sinocyclocheilus) 17个种的核DNA含量。结果显示 ,除侧条金线 (S .lateristritus)中采自云南沾益炎方山那边的样本之 2C值为 7 79pg外 ,其余的核DNA 2C值都集中分布在 4 19～ 4 86pg范围 ,大体与其近缘四倍体种 2C值相同或相近 ,是其近缘二倍体种 2C值的大约 2倍。据此我们推断 ,这 17种金线很可能都是四倍体 ,个别种还含有八倍体的类型 ,金线属可能是整属的四倍体起源。     

草鱼雌核发育后代不同群体的微卫星遗传分析及指纹识别

以紫外线灭活的团头鲂精子激活草鱼卵子,冷休克抑制第二极体排出的方法诱导出长江水系优良F2代草鱼减数雌核发育子代。在后代中不仅存在雌核发育后代,还存在草鲂杂交后代,雌核发育后代的体型与草鱼一致,而草鲂杂交后代的体型介于草鱼与团头鲂之间。Partec CyFlow倍性分析仪测定结果显示:普通草鱼与雌核发育草鱼的相对DNA含量分别为23.01和22.72,二者的DNA含量接近;而高体型子代的相对DNA含量为25.38,介于草鱼与团头鲂（DNA含量28.21）之间,属于草鲂杂交后代。选取17个微卫星标记对草鱼群体、雌核发育草鱼群体和草鲂杂交后代的遗传多样性进行了检测,共检测出59个等位基因,其中43.18个有效等位基因。草鱼对照群体、草鲂杂交后代和雌核发育草鱼群体的平均等位基因依次为3.57、2.86和2.79,平均有效等位基因依次为2.93、2.37和1.96,平均期望杂合度在依次为0.6502、0.5573和0.3775,多态信息含量（PIC）平均值依次为0.5738、0.4649和0.3791。与草鱼对照群体相比,雌核发育草鱼群体的遗传多样性显著下降,表明通过减数雌核发育方法可获得纯合性较高的草鱼个体。构建了草鱼后代不同群体的DNA指纹模式图,筛选到不同群体的9个特异微卫星标记,为草鱼优良群体的选育提供了基础资料。     

Assessment of genetic stability of the germplasm lines of medicinal plant <Emphasis Type="Italic">Scutellaria baicalensis</Emphasis> Georgi (Huang-qin) in long-term,in vitro maintained cultures

An approach of combining flow cytometry (FCM) analysis with morphological and chemical profiling was used to assess the genetic stability and bioactive compound diversity in a Scutellaria baicalensis Georgi (Huang-qin) germplasm collection that was clonally maintained in in vitro for a period of over 6 years. Based on the FCM analysis of nuclei samples from young shoots, the nuclear DNA content of S. baicalensis was calculated as 0.84 pg/2C. FCM analysis showed no significant variation in the nuclear DNA contents and ploidy levels in the long-term in vitro maintained germplasm lines. Germplasm lines, acclimatized to ex vitro conditions, exhibited distinctive plant growth and bioactive compound production capacities. The high level of genetic stability observed in in vitro maintained S. baicalensis lines opens up a variety of opportunities such as allowing long-term aseptic preservation and easy distribution of well-characterized germplasm lines of this medicinal plant species. This study represents a novel approach for continuous maintenance, monitoring, and production of medicinal plant tissues with specific chemistry.     

Nuclear DNA content of Vitis vinifera cultivars and ploidy level analyses of somatic embryo-derived plants obtained from anther culture

Flow cytometry was employed to determine the ploidy level of Vitis vinifera L. somatic embryo-derived plants obtained from anther culture. Only one among the 41 analysed plants (2.4%) presented somaclonal variation (tetraploidy); the other plants were diploid. No significant differences (P≤0.05) were detected between diploid and parental field plants. No haploid or aneuploid plants were observed. The nuclear DNA content of nine V. vinifera cultivars was also estimated using flow cytometry. A non-significant variation was found among the cultivars, with DNA content ranging from 1.17 pg/2C (cv. ‘Tinta Barroca’ and ‘Viosinho’) to 1.26 pg/2C (cv. ‘Cabernet Sauvignon’). These results and previous studies on other Vitis species suggest that Vitis genome is stable with regard to nuclear DNA content.     

Morphometry of nuclear and nucleolar structures in a CaCo-2 cell line

The number of the nucleoli in a CaCo-2 cell nucleus does not generally depend on the quantity of DNA in the nucleus, but nucleolar DNA content is directly proportional to total nuclear DNA. However, in multinucleolar cells (three or more nucleoli), the nucleolar DNA content increases after 96 h incubation in culture without concomitant quantitative changes in nuclear DNA. The percentage of multinucleolar cells and the average number of nucleoli per nucleus increase with increasing incubation time. After 72 and 96 h in culture, multinucleolar cells show distinctive morphologies. The ratio of the sum of nucleolar perimeters to the nuclear perimeter increases linearly when the number of nucleoli in a nucleus increases, but there is no concomitant increase in total nucleolar area or DNA content, except in the 72 and 96 h populations. When the number of nucleoli in CaCo-2 cells increases after 48 and 60 h in culture, the amount of DNA per nucleolus decreases.     

山茶属山茶组的细胞地理学研究

本文总结了山茶组植物的细胞学资料,结合形态和地理学特征讨论了该组植物扩散及分化的规律。山茶组具有相同的染色体基数,变化较大的倍性。其中子房无毛的种类除Ｃ．ｃｈｅｋｉａｎｇｏｌｅｏｓａ Ｈｕ,Ｃ．ｊａｐｏｎｉａｃａ Ｌ．的个别居群外都是二倍体;多倍体主要出现在苞,萼,后发脱落,子房被毛的种类中,分布于南岭以西至西南地区,南岭及南岭在东,以南地区未发现多倍体。