唐古特白刺研究现状与建议

唐古特白刺(Nitraria tangutorum Bobr.)是白刺属中较进化的植物种,众多克隆株系形成"白刺包",具有重要的生态防护价值,其浆果状核果也具有较高的经济利用价值.由于种内异交和种间杂交,唐古特白刺种内变异十分丰富,其中表现最为明显的是果实性状变异.而果色、果味、果序重等性状差异,对于生产成本、加工工艺以及产品质量等都有较大影响,从而限制了白刺果的产业化开发.开展种质资源、优树选择、杂交和倍性育种等方面的研究,对唐古特白刺进行遗传改良,选育高产、味佳、核小、色泽美观且生态价值高的果用与生态兼用型白刺品种,并进一步使其无性系化、种植园化,则是推动沙区白刺资源开发、利用以及当地生态与经济发展的关键.     

都兰钝额斑螟的生物学特性及四种杀虫剂的室内毒力测定

都兰钝额斑螟Bazaria dulanensis Du et Yan是柴达木盆地南部地区唐古特白刺(Nitrada tangutorum Bobr.)灌丛的主要害虫之一.为有效控治该害虫对唐古特白刺的危害,本研究采用室内饲养和田间定点观察,对其生物学特性进行观察,结果表明:都兰钝额斑螟在柴达木盆地一年发生1代,幼虫共5...     

唐古特白刺黄酮类物质及其药用研究进展CSCD

唐古特白刺(Nitraria tangutorum Bobr.)是一种具有药用、食用和饲用价值的荒漠植物,主要分布于我国西北干旱半干旱地区。白刺被誉为沙漠樱桃,含有多种营养物质,还富含黄酮、生物碱等多种药用成分,因此人们对其药用成分、含量、功效及药理展开了一系列研究。本文对现有唐古特白刺黄酮类物质相关的研究进行了调研,首先对唐古特白刺中已分离出的黄酮类物质进行分类,其次对唐古特白刺主要组织中总黄酮含量进行整理和分析,另外对唐古特白刺中各种黄酮化合物的含量进行分析,最后对唐古特白刺中总黄酮、各类黄酮、黄酮单体化合物的药效及药理进行综述。通过对上述内容的整理和分析,总结出白刺黄酮类物质药用研究中存在的一系列问题,并基于此提出解决现有问题的思路并对未来白刺黄酮药用研究提出建议,以期为唐古特白刺植物黄酮类物质药用研究和开发提供理论参考,推动中医药行业的发展。     

唐古特白刺叶性状及叶片δ13C、δ15N沿降水梯度的变化特征

叶片性状反映了植物对环境的适应能力及自我调控能力。以唐古特白刺天然种群为研究对象,沿300—40 mm年降水梯度,测定了7个样地的唐古特白刺叶片性状及叶片δ~(13)C、δ~(15)N。结果表明:(1)沿降水梯度变化,7个地区唐古特白刺叶宽、长宽比、叶厚、叶面积、比叶面积、叶氮含量、叶片δ~(13)C和δ~(15)N变异性显著(P0.05),而叶长差异不显著(P0.05)。唐古特白刺通过叶片各功能性状间的调节来适应环境的变化,并形成性状间的最佳功能组合。(2)唐古特白刺叶片δ~(13)C与叶面积、比叶面积呈负相关关系,与叶氮含量呈正相关关系,但其相关性均未达到显著性水平(P0.05),仅与地下水埋深表现出了极显著的正相关关系(P0.01)。在降水量小于100 mm的区域,白刺主要利用地下水源,成为隐域植被,从而降低了对其他环境因子的响应。(3)叶片厚度和叶氮含量可以作为体现不同地区间唐古特白刺差异的叶功能性状。数据显示叶片厚度与年平均温度正相关(P0.05),尤其与年最高气温大于35℃日数关系更为密切(P0.01);在高温环境下,叶片增厚的同时叶氮含量显著降低(P0.05),而这一过程中叶片δ~(15)N值却有增加趋势(R~2=0.62,P0.05),因此叶厚度和叶氮含量对叶片δ~(15)N的相对影响在干旱与半干旱区之间发生转变,这为进一步探究干旱区荒漠植被的水分限制阈值提供了新思路。     

甘肃民勤西沙窝唐古特白刺群落的生态特性

对甘肃民勤西沙窝唐古特白刺 (NitrariatangotorumBobr.)群落的物种组成、种间关系、垂直结构、周期性和物种多样性的研究结果表明 :该唐古特白刺群落由 34种植物组成 ,隶属 11科 31属 ,属的分布类型以地中海、西亚至中亚成分为主 ;灌木层平均高 0 .43m ,包括高位芽和地上芽 2种生活型层片 ,根系多分布至 1.5m以下的土层中 ,根幅 >2m× 2m ;草本层平均高 0 .0 9m ,包括地面芽、地下芽和一年生植物 3个生活型层片 ,根系多分布于 0～ 1.5m以内的土层中 ,层片丰富 ,层片结构简单 ;群落周期性变化明显。微型叶植物占总种数的 5 0 .0 0 %,小型叶占2 3.5 3%,鳞型叶占 14.71%,中型叶占 11.76 %,无大型叶和巨型叶 ;种间关系单纯 ,种群呈聚集型分布格局 ;演替处于进展与逆行演替的阈上 ,非常脆弱和不稳定 ,必须科学地保护。     

基于ITS和trnL-F序列碱基差异的繁缕及其近缘种的亲缘关系分析

应用PCR产物直接测序法分析了繁缕[Stellaria media(L.)Villars]及其近缘种和鹅肠菜[Myosoton aquaticum (L.)Moench]的ITS和trnL-F序列的碱基差异,并以孩儿参[Pseudostellaria heterophylla(Miq.)Pax]为外类群构建N-J系统树,分析了这些种类的种间亲缘关系.结果表明,供试的繁缕属(Stellaria L.)种类及鹅肠菜的ITS和trnL-F序列长度分别为521～784和788～951 bp,各有变异位点77和59个,其中信息位点分别为18和11个,种间碱基差异百分率分别为6.5%和3.1%.ITS的碱基组成为A 22.1%、T20.9%、G 28.5%和C 28.5%,G+C含量57.0%;trnL-F的碱基组成为A 35.9%、T 33.7%、G 15.7%和C 14.8%,G+C含量30.5%.繁缕、雀舌草(S.alsine Grimm)和箐姑草(S.vestita Kurz)的ITS和trnL-F序列一致;鹅肠菜的ITS序列中有4个位点与前述种类不同,但trnL-F序列则相同;中国繁缕(S.chinensis Regel)的ITS和trnL-F序列与孩儿参较相似.在N-J系统树中,鹅肠菜与繁缕、雀舌草和箐姑草聚为一支,表明它们的亲缘关系相对较近,支持将鹅肠菜重新归入繁缕属的分类处理.研究结果显示,ITS和trnL-F序列分析均可用于繁缕及其近缘种的鉴别,且ITS是更为适宜的分子标记.     

盐胁迫下唐古特白刺对外源Ca2+的生理响应

为探讨Ca2+与盐生植物耐盐性的关系,以唐古特白刺(Nitraria tangutorum)为试验材料,研究不同浓度外源Ca2+对盐胁迫下唐古特白刺的生理响应,结果表明,盐浓度不高于300 mmol·L-1时,施加定浓度Ca2+(≤15 mmol·L-1)可增加唐古特白刺叶片相对含水量,提高叶片水势与根系活力,降低电解质外渗率,减少MDA含量,增加脯氨酸的积累,同时提高SOD和POD活性,且这种趋势随Ca2+浓度的增加而增加。而高浓度Ca2+(>15 mmol·L-1)对唐古特白刺各生理指标均表现出不同程度的抑制作用,影响唐古特白刺的正常代谢活动。说明定浓度的Ca2+(≤15 mmol·L-1)能有效缓解盐胁迫(NaCl≤300mmol·L-1)对唐古特白刺造成的伤害,高盐胁迫下外施Ca2+缓解作用不明显,甚至表现为抑制作用。     

基于叶绿体DNA序列分析东亚七筋姑的遗传进化

通过对东亚七筋姑(Clintoniaudensis Trautv.etMey.)19个居群的cpDNA基因间隔区(cpDNA intergenic regions)rpl20-rps12和trnL-F进行序列分析,结果表明,当空位(Gap)作缺失处理时,trnL-F全序列排序后的长度为754个位点,G C含量为35.2%～35.8%,rpl20-rps12序列排序后长度为814bp,G C含量为34.1%～34.3%.聚类结果显示四倍体居群没有单独聚为一支,其多倍体可能是同源多倍体,起源方式属于异地多起源.     

唐古拉特白刺和西伯利亚白刺叶挥发性成分研究

利用固相微萃取技术提取唐古拉特白刺和西伯利亚白刺叶的挥发性成分,采用气相色谱-质谱联用结合保留指数法鉴定了其成分。分别从唐古拉特白刺叶和西伯利亚白刺叶中的挥发油中鉴定出40、33个化合物,二者共有成分27个。对比二者的挥发性成分,发现唐古拉特白刺叶烃类化合物(25.54%),远高于西伯利亚白刺叶(12.00%),并且以二十一烷为转折点,在此之前,各烃类化合物的在唐古拉特白刺叶中的含量均高于西伯利亚白刺叶,在此之后,烃类化合物在前者中的含量低于后者;乙酸仅存在于西伯利亚白刺叶中,且含量高达20.00%,二氢猕猴桃内酯为二者叶中的主要赋香成分。     

唐古特白刺果实化学成分和功效作用研究进展

唐古特白刺是中国特有的白刺属植物,民间用于治疗脾胃虚弱、消化不良、神经衰弱、感冒等症。本文综述了唐古特白刺果实化学成分和功效作用方面的研究进展。     

基于种皮形态和叶绿体trnL-F对菘蓝属（十字花科）的系统学位置研究

利用种皮微形态观察与叶绿体DNA的trnL内含子和trnL-F基因间隔区序列测定分析相结合,对十字花科菘蓝属植物及其相关属种的系统学关系进行了探讨.研究结果表明原属独行菜族的菘蓝属植物,其种皮特征与原属鸟头荠族的舟果荠属植物相似,同属一类型.而与独行菜族的模式属独行菜属植物、大蒜芥族的模式属大蒜芥属植物以及鸟头荠族的模式属鸟头荠属植物种皮微形态差异显著;在基于叶绿体DNA的trnL内含子和trnL-F基因间隔区序列所构建的系统发育树中,菘蓝属植物与舟果荠属植物距离最近,而与独行菜属、大蒜芥属、鸟头荠属植物具有一定的间隔,结合形态特征,本研究认为,菘蓝属与舟果荠属植物具有较近的亲缘关系,而不是同族的独行菜属植物.     

Towards a Phylogeny for Coffea (Rubiaceae): identifying well-supported lineages based on nuclear and plastid DNA sequences

BACKGROUND AND AIMS: The phylogenetic relationships between species of Coffea and Psilanthus remain poorly understood, owing to low levels of sequence variation recovered in previous studies, coupled with relatively limited species sampling. In this study, the relationships between Coffea and Psilanthus species are assessed based on substantially increased molecular sequence data and greatly improved species sampling. METHODS: Phylogenetic relationships are assessed using parsimony, with sequence data from four plastid regions [trnL-F intron, trnL-F intergenic spacer (IGS), rpl16 intron and accD-psa1 IGS], and the internal transcribed spacer (ITS) region of nuclear rDNA (ITS 1/5.8S/ITS 2). Supported lineages in Coffea are discussed within the context of geographical correspondence, biogeography, morphology and systematics. KEY RESULTS: Several major lineages with geographical coherence, as identified in previous studies based on smaller data sets, are supported. Other lineages with either geographical or ecological correspondence are recognized for the first time. Coffea subgenus Baracoffea is shown to be monophyletic, but Coffea subgenus Coffea is paraphyletic. Sequence data do not substantiate the monophyly of either Coffea or Psilanthus. Low levels of sequence divergence do not allow detailed resolution of relationships within Coffea, most notably for species of Coffea subgenus Coffea occurring in Madagascar. The origin of C. arabica by recent hybridization between C. canephora and C. eugenioides is supported. Phylogenetic separation resulting from the presence of the Dahomey Gap is inferred based on sequence data from Coffea.     

花椒cpDNA trnL-F间隔区序列的特征及其在混淆品鉴别中的应用

目的:通过分析花椒cpDNA trnL-F间隔区序列特点,探讨该序列在花椒与其混淆品鉴别中的意义.方法:对花椒及其混淆品进行cpDNA trnL-F间隔区序列比较研究.结果:花椒cpDNA trnL-F间隔区序列为349bp、AT百分比为62.1%.尽管花椒的果实在外部形态,物理特性上与混淆品差异较小,但在cpDNA trnL-F间隔区序列上却存在着显著而稳定的差异.该序列在属以下的分类阶元中同源性极高,可达100%.结论:根据cpDNA trnL -F间隔区碱基序列的差异,能有效地鉴别花椒及其属以上分类阶元的混淆品.     

Phylogenetic relationships among Strobilanthes s.l. (Acanthaceae): evidence from ITS nrDNA, trnL-F cpDNA, and morphology

Chloroplast trnL-F sequence data, nuclear ribosomal internal transcribed spacer (ITS) sequence data, and morphology were used to analyze phylogenetic relationships among members of the subtribe Strobilanthinae. Parsimony and maximum likelihood analyses of trnL-F indicate that the Strobilanthinae are a monophyletic group. While parsimony analysis of ITS recovers a nonmonophyletic subtribe, maximum likelihood analysis of ITS corroborates results from trnL-F and suggests that systematic error is impacting on ITS parsimony analysis. A combined ITS and trnL-F analysis strengthens the signal and also recovers a monophyletic subtribe. All analyses indicate that Hemigraphis, Sericocalyx, and Strobilanthes are nonmonophyletic. With one exception, all morphological characters included in a combined ITS and morphological analysis are homoplastic. The prospect for a new informative generic classification of the Strobilanthinae aiming to recognize and diagnose only monophyletic groups is considered. While some groups can be diagnosed, adequate diagnosis of the majority of groups remains problematic. Consequently, a single expanded genus Strobilanthes sensu lato is proposed at the level of the well-supported and monophyletic Strobilanthinae.     

Molecular evolution of the trnTUGU-trnFGAA region in Bryophytes

Structure, variability, and molecular evolution of the trnT-F region in the Bryophyta (mosses and liverworts) is analyzed based on about 200 sequences of the trnT-L spacer and trnL 5' exon, 1000 sequences of the trnL intron, and 800 sequences of the trnL 3' exon and trnL-F spacer, including comparisons of lengths, GC contents, sequence similarities, and functional elements. Mutations occurring in the trnL 5' and 3' exons, including compensatory base pair changes, and a transition in the trnL anticodon in Takakia lepidozioides, are discussed. All three non-coding regions display a mosaic structure of highly variable elements (V1 - V3 in the trnT-L spacer, V4/V5 corresponding to stem-loop regions P6/P8 in the trnL intron, and V6/V7 in the trnL-F spacer) and more conserved elements. In the trnL intron this structure is a consequence of the defined secondary structure necessary for correct splicing, whereas in both spacers conserved regions are restricted to promoter elements. At least the highly variable regions in the trnT-L spacer and stem-loop region P8 of the trnL intron seem to evolve independently in the major bryophyte lineages and are therefore not suitable for high taxonomic level phylogenetic reconstructions. In mosses, a trend of length reduction towards the more derived lineages is observed in all three non-coding regions. GC contents are mostly linked to sequence variability, with the conserved regions being more GC rich and the more variable AT rich. The lowest GC values (< 10 %) are found in the trnT-L spacer of mosses. In addition to two putative sigma (70)-type promoters in the trnT-L spacer, a third putative promoter is present in the trnL-F spacer, although trnL and trnF are assumed to be co-transcribed. Consensus sequences are provided for the -35 and -10 sequences of the major bryophyte lineages. The third promoter is part of a hairpin secondary structure, whose loop region is highly homoplastic in mosses due to an inversion occurring independently in non-related taxa, even at the intraspecific level.     

罗布麻及其易混品的DNA分子鉴定

为从分子水平更准确地鉴别罗布麻及其易混品,本研究利用PCR产物直接测序法对罗布麻、大叶白麻和Apoacynum cannabinum的核基因组（rDNA）ITS区与叶绿体基因组（cpDNA）trnL内含子及trnL-F间隔区序列进行测序与比较。结果显示,罗布麻和大叶白麻ITS序列完全一致,与A. cannabinum在ITS1区有13个位点、在ITS2区有10个位点不同;在trnL内含子区及trnL-F间隔区,罗布麻和大叶白麻共有3个位点不同,罗布麻和A. cannabinum间共有23个位点、大叶白麻和A. cannabinum间共有20个位点不同。研究表明,依据rDNA ITS区序列可鉴别A. cannabinum和国产“罗布麻”（罗布麻与大叶白麻）;利用cpDNA trnL内含子及trnL-F间隔区序列可鉴别罗布麻及其相似种。     

Phylogenetic relationships in Leymus (Poaceae: Triticeae) revealed by the nuclear ribosomal internal transcribed spacer and chloroplast trnL-F sequences

Using the nuclear ribosomal internal transcribed spacer (ITS) sequences and the chloroplasttrnL-F sequence, phylogeneic analysis was performed on 57 accessions of species in the tribe Triticeae including 13 Leymus species (N(s)) with different ploidy levels and 40 diploid species from 18 genera. The ITS sequences revealed that ployploid Leymus has close phylogentic relationships with Psathyrostachys and an undefined genus in Triticeae. The trnL-F tree demonstrated close relationships between certain Leymus species and Psathyrostachys, and other Leymus species distributed in North America were far from Psathyrostachys. Based on these results, it is unlikely that the unknown genome in Leymus species originated from one of the sampled diploid species in the present study. The maternal donor of all the Leymus species with a natural distribution in Eurasia were N(s) genome. Furthermore, Elymus californicus should be transferred from the genus Elymus to Leymus.     

Phylogenetic relationships in Nicotiana (Solanaceae) inferred from multiple plastid DNA regions

For Nicotiana, with 75 naturally occurring species (40 diploids and 35 allopolyploids), we produced 4656bp of plastid DNA sequence for 87 accessions and various outgroups. The loci sequenced were trnL intron and trnL-F spacer, trnS-G spacer and two genes, ndhF and matK. Parsimony and Bayesian analyses yielded identical relationships for the diploids, and these are consistent with other data, producing the best-supported phylogenetic assessment currently available for the genus. For the allopolyploids, the line of maternal inheritance is traced via the plastid tree. Nicotiana and the Australian endemic tribe Anthocercideae form a sister pair. Symonanthus is sister to the rest of Anthocercideae. Nicotiana sect. Tomentosae is sister to the rest of the genus. The maternal parent of the allopolyploid species of N. sect. Polydicliae were ancestors of the same species, but the allopolyploids were produced at different times, thus making such sections paraphyletic to their extant diploid relatives. Nicotiana is likely to have evolved in southern South America east of the Andes and later dispersed to Africa, Australia, and southwestern North America.     

5种苍术属药用植物的trnL-F序列测定及种间遗传关系分析

采用PCR技术对5种苍术属(Atractylodes DC.)药用植物的trnL-F序列进行测定及比较分析。结果表明,扩增获得的序列长886~902 bp,经排序并两端切平后,序列长816 bp,G C含量为34.4%;当空位始终做缺失处理时,产物有5个变异位点。利用trnL-F序列可准确鉴别出朝鲜苍术〔A.koreana(Nakai)Kitam.〕、北苍术〔A. chinensis(DC.)Koidz.〕和白术(A.macrocephalaKoidz.);而茅苍术〔A.lancea(Thunb.)DC.〕与关苍术(A.japonicaKoidz.ex Kitam.)的trnL-F序列则完全一致,相互之间无法区分。采用邻接法和UPGMA法得到的5种苍术属药用植物的分子系统树有一定的差异,表明这5种苍术属药用植物的物种分化不完全,序列进化不一致。     

Phylogenetic relationships in Elymus (Poaceae: Triticeae) based on the nuclear ribosomal internal transcribed spacer and chloroplast trnL-F sequences

To estimate the phylogenetic relationship of polyploid Elymus in Triticeae, nuclear ribosomal internal transcribed spacer (ITS) and chloroplast trnL-F sequences of 45 Elymus accessions containing various genomes were analysed with those of five Pseudoroegneria (St), two Hordeum (H), three Agropyron (P) and two Australopyrum (W) accessions. The ITS sequences revealed a close phylogenetic relationship between the polyploid Elymus and species from the other genera. The ITS and trnL-F trees indicated considerable differentiation of the StY genome species. The trnL-F sequences revealed an especially close relationship of Pseudoroegneria to all Elymus species included. Both the ITS and trnL-F trees suggested multiple origins and recurrent hybridization of Elymus species. The results suggested that: the St, H, P, and W genomes in polyploid Elymus were donated by Pseudoroegneria, Hordeum, Agropyron and Australopyrum, respectively, and the St and Y genomes may have originated from the same ancestor; Pseudoroegneria was the maternal donor of the polyploid Elymus; and some Elymus species showed multiple origin and experienced recurrent hybridization.