中国东北落叶松属植物rbcL 基因的序列分析及系统演化

长白落叶松的分类位置及与兴安落叶松的种间关系, 长期以来未有定论。本研究从大兴安岭、小兴安岭及张广才岭等6 个地点采集实验材料, 对其叶绿体DNA 的rbcL 基因进行PCR-RFLP 分析并测序。结果显示它们的rbcL 基因序列均没有差异, 表明东北地区落叶松属植物有共同起源。在系统演化上, 长白落叶松来自兴安落叶松(Larix gmelinii Rupr.), 应作为兴安落叶松的变种即L.gmelinii Rupr.var.olgensis Ostenfeld et S.Larsen     

中国东北落叶松属植物亲缘关系的研究

本文用RAPD方法对中国东北落叶松属植物的亲缘关系进行了研究。从100个引物中筛选出41个引物,检测出120个多态位点。应用UPGMA法计算了种群内和种群间的遗传距离,并构建了系统树。实验结果表明,分布在长白山的落叶松与分布在大、小兴安岭的落叶松之间的差异,在遗传距离上还不能达到种间分化水平。分布在长白山的落叶松应视为兴安落叶松种下的变种,分布在东京城的落叶松可能是兴安落叶松与长白山落叶松的杂交种。     

松毛虫属（Dendrolimus) 部分种类亲缘关系与遗传分化的等位酶分析

采用等位酶聚丙烯酰胺凝胶电泳技术对松毛虫属5个种和亚种的野生种群进行了亲缘关系和遗传变异的研究.8种等位酶系统(乳酸脱氢酶LDH、苹果酸脱氢酶MDH、苹果酸酶ME、乙醇脱氢酶ADH、甲酸脱氢酶FDH、谷氨酸脱氢酶GDH、过氧化物酶POD、过氧化氢酶CAT)共检测到12个基因位点,其中6个位点为多态位点,检测到15个等位基因.松毛虫属5个种和亚种的总体水平多态位点比率P＝50%,平均有效基因数A = 1.917,平均期望杂合度He =0.267,平均遗传距离为0.0730～0.5701.遗传参数表明松毛虫属昆虫种间存在较高程度的遗传变异,聚类图和遗传距离数据表明赤松毛虫与马尾松毛虫亲缘关系最近,落叶松毛虫与思茅松毛虫亲缘关系最远.     

中国东北落中松属植物亲缘关系的研究

本文用ＲＡＰＤ方法对中国东北落叶松属植物的亲缘关系进行了研究。从１００个引物中筛选出４１个引物,检测出１２０个多态位点。应用ＵＰＧＭＡ法计算了种群同人和群间的遗传距离,并构建了系统树。实验结果表明,分布在长白山的落叶松与分布在大、小兴安岭的落叶松之间的差异,在遗传距离上还大能达到种间分化水平。分布在长白山的落叶松应视为兴安落叶松种下的变种,分布在东京城的落叶松可能是安落叶松与长白山落叶松的杂交种。     

短葶飞蓬云南三个种群的核型与等位酶分析

通过核型和等位酶分析,对短葶飞蓬（Erigeron breviscapus)种群遗传结构进行了较全面的研究。研究材料来自丽江,昆明,邱北,核型分析表明,这3个种群都为二倍体种群（2n=2x=18),以丽江种群为例,短葶飞蓬核型为2n=2x=18=6m 10sm(2SAT) 2st,10种酶的等位酶分析表明,短葶飞蓬的遗传变异存在于种群内,种群间遗传一致度高（I=0.9172),遗传距离小（D=0.0876),遗传距离与空间距离大致成正相关。     

青藏高原垂穗披碱草遗传变异的地理因素分析

采用等位酶标记对我国青藏高原地区垂穗披碱草的9个种群进行遗传变异和系统关系分析.结果表明,不同种群间遗传距离范围在0.010 6-0.377 8,种群间遗传距离和地理环境关系密切.采用聚类分析和二维、三维Mantel检验,对青藏高原垂穗披碱草(Elymusnutans Griseb.)不同种群间遗传距离与环境条件的关系(纬度、经度和海拔)进一步分析发现,海拔和地理位置(纬度和经度)均明显影响垂穗披碱草种群遗传差异.种群间遗传距离和海拔(R=0.476 8)、地理位置(R=0.447 1)均呈现显著正相关,种群间遗传距离随着海拔、地理位置差距的增大而增加,但海拔是影响其遗传结构的最重要因素,其次是经纬度.     

兴安、长白及华北落叶松RAPD 分子标记的物种特异性鉴定

以中国北方地区主要乡土落叶松树种兴安落叶松(Larix gmelini)、长白落叶松(L. olgensis)和华北落叶松(L. principisrupprechtii)的针叶及种子胚乳为研究材料, 采用RAPD分子标记技术对3种落叶松进行不同物种的种间鉴别。结果表明, 通过引物筛选得到了4个可以鉴别3种落叶松的RAPD引物, 其中有2个引物在落叶松针叶和种子胚乳基因组中都扩增出相同的条带。引物OPB-11在兴安和长白落叶松基因组DNA中1 500 bp处扩增出特异条带, 而在华北落叶松中没有; 引物OPX-14在兴安落叶松基因组DNA中1 200 bp处扩增出特异条带, 而在长白落叶松中没有; 还有2个引物可分别作为3种落叶松苗木和种子鉴别的辅助标记。本研究从分子水平上为落叶松的种间鉴别提供了新的鉴定方法。     

内蒙古西伯利亚杏群体遗传多样性和遗传结构分析

利用27对SSR分子标记对内蒙古地区13个西伯利亚杏群体的遗传多样性和遗传结构进行分析,评价其遗传多样性水平和分化程度,为内蒙古西伯利亚杏资源的合理保护与利用提供理论依据。结果显示:(1)27对SSR引物共检测到512个等位基因(Na),各位点平均等位基因数(Na)和多态性信息含量(PIC)分别为19和0.84;物种水平上Shannons信息指数(I)和期望杂合度(He)分别为2.25和0.73。(2)群体水平上的等位基因(Na)、有效等位基因(Ne)、Shannons信息指数(I)、期望杂合度(He)和观察杂合度(Ho)分别为6.95、4.48、1.60、0.76和0.56;其中科左后旗群体遗传多样性最丰富,克什克腾旗群体遗传多样性最低。(3)基于F统计量分析的遗传分化系数(Fst)为0.12,基因流(Nm)为1.86;分子方差分析显示内蒙古西伯利亚杏群体大部分遗传变异来自群体内(92%),群体间的遗传变异仅占8%。(4)内蒙古西伯利亚杏群体遗传距离为0.04~0.67,遗传相似度为0.33~0.83;遗传相似度的聚类分析、遗传距离的主坐标分析和遗传结构分析(Structure)均将供试13个群体划分为4组。Mantel检测显示,内蒙古西伯利亚杏群体遗传距离与地理距离呈显著相关关系(r=0.453,P0.01)。研究表明,内蒙古西伯利亚杏资源具有丰富的遗传多样性,这一特性与其群体的大小、悠久的演化历史以及自身生物学特性相关;内蒙古西伯利亚杏群体间存在中等程度的遗传分化,这可能源于自然地理隔离以及近期人类活动引起的生境片段化。     

中国红豆杉属及其近缘植物的遗传变异和亲缘关系分析

采用水平式淀粉凝胶电泳技术,对中国产红豆杉属Taxus 3种1变种以及白豆杉Pseudotaxus chienii共12个居群的遗传多样性进行了检测。对7个酶系统9个酶位点的分析结果表明,红豆杉属和 白豆杉的种内遗传多样性水平较高,各类群的多态位点比率(P)为44.4％～77.8％,等位基因平均数 (A)为1．6～2．1,平均期望杂合度(He)和实际观察杂合度(Ho)分别为0.065～0.152和0.068～0.111。 根据对等位酶实验结果的分析,结果表明除云南红豆杉T．yunnanensis与红豆杉属其它几个种的遗传 一致度稍低(I=0.727～0.804)外,红豆杉属的其它几个种的遗传一致度较高(0.906～0.995),体现其 亲缘关系很近。笔者建议将红豆杉属的这几个种合并为一个种,并根据地理分布及不同生境发生的变 异在种下设地理宗。同时根据等位酶的实验分析结果,白豆杉和红豆杉属各种的比较有显著差异,支持白豆杉作为单独属Pseudotaxus的处理。     

九种杜鹃属植物的遗传分化研究

采用水平淀粉凝胶电泳技术 ,对 9种杜鹃属 ( Rhododendron)植物的遗传分化进行了初步研究。对 10个酶系统的 14个等位酶位点的检测表明 ,9种杜鹃花在种内个体间的遗传变异水平较高 ,多态位点比率数为 P=2 8.6%～ 57.1% ,等位基因平均数 A=1.3～ 1.9,平均预期杂合度 He=0 .111～ 0 .319,平均观察杂合度 Ho=0 .0 83～ 0 .381。种间的多态位点比率非常高 P=10 0 % ,这说明杜鹃属种间的遗传分化较高 ,具有丰富的遗传多样性。杂合性基因多样化比率 Fst=0 .683,表明各种间存在明显的遗传分化现象     

Nuclear and cytoplasmic variation within and between Eurasian Larix (Pinaceae) species

The genetic variation in nuclear and cytoplasmic markers was investigated in 28 populations belonging to Eurasian Larix species (L. decidua, L. sibirica, L. gmelinii, L. olgensis, and L. kaempferi). Nuclear genetic variation was assessed at 214 AFLP loci, and both PCR-RFLP and four microsatellite loci were used to estimate variation of the chloroplast DNA. Variation of the mitochondrial genome was measured using RFLPs. Although population differentiation at both nuclear and chloroplast markers was much weaker than at mitochondrial DNA, it nonetheless corroborated the grouping observed with mitochondrial DNA. The AFLPs led to the same population grouping as mtDNA. Notably, the presence of two ancient western and eastern groups within L. sibirica was confirmed and possible postglacial routes inferred. The genetic composition of the northernmost L. sibirica population in our sample established that it is located at the confluence of the eastern and western recolonization routes. The joint use of the three markers also indicated that populations around Lake Baikal are hybrids between L. gmelinii and L. sibirica, with L. gmelinii primarily acting as the pollinator. Finally, AFLP-based estimates of nucleotide variation were an order of magnitude larger than the strikingly low estimates of nucleotide variation recently reported in Pinus sylvestris.     

Reconstruction of the phylogenetic position of larch (Larix sukaczewii Dylis) by sequencing data for the trnK intron of chloroplast DNA

To reconstruct the systematic relationships of larch Larix sukaczewii, we used the chloroplast trnK intron sequences of L. decidua, L. sukaczewii, L. sibirica, L. czekanovskii, and L. gmelinii. Analysis of phylogenetic trees constructed using the maximum parsimony and maximum likelihood methods showed a clear divergence of the trnK intron sequences between L. sukaczewii and L. sibirica. This divergence reaches intraspecific level, which supports a previously published hypothesis on the taxonomic isolation of L. sukaczewii.     

Phylogeography of Eurasian Larix species inferred from nucleotide variation in two nuclear genes

Larch (Larix Mill.) is one of the most widely distributed tree genera in Eurasia. To determine population structure and to verify classification of five species and three varieties of the Eurasian Larix species, we investigated levels and patterns of nucleotide variation of two nuclear gene regions: the 4-coumarate coenzyme A ligase (4CL) and the coumarate 3-hydroxylase (C3H). In the 4CL region nucleotide diversity at silent sites (pi(sil)) varied between 0.0020 in L. gmelinii to 0.0116 in L. gmelinii var. japonica and in the C3H region between 0.0019 in L. kaempferi to 0.0066 in L. gmelinii var. japonica. In both gene regions statistically significant population differentiation (F(ST)) was detected among adjacent refugial populations of some species suggesting limited gene flow and/or long time isolation of some refugial populations. On the other hand, populations of L. sukaczewii from northwestern Russia, which was glaciated 20,000 years ago showed no differentiation. This result is consistent with recent postglacial origin of these populations. Haplotype composition of some of the investigated Eurasian Larix species suggested that they are considerably diverged. Some haplotypes were unique to individual species. Our results indicate that more intensive sampling especially from known refugial regions is necessary for inferring correct classification of Eurasian Larix species and inferring their postglacial migration.     

Evolution of 4-coumarate:coenzyme A ligase (4CL) gene and divergence of Larix (Pinaceae)

The evolutionary dynamics of the 4CL gene encoding 4-coumarate:coenzyme A ligase was investigated in the genus Larix (Pinaceae) by comparing copy number, GC content and codon usage, sequence divergence, and phylogenetic analysis. All 4CL clones of Larix formed a strongly supported monophyletic group, in which two robust clades (4clA and 4clB) derived from an ancient gene duplication event in the common ancestor of Larix were identified. Further gene duplication in the 4clA clade gave rise to two subclades 4clA(1) and 4clA(2). Frequent duplication/deletion appears to be a common evolutionary phenomenon in the 4CL gene family and paralogous genes differ greatly in their evolution rate. The existence of L. speciosa in subclades 4clA(1) and 4clA(2) suggests that this species may represent a primitive form of Larix or the closest relative of the common ancestor of the Eurasian Sect. Multiserialis. In addition, cpDNA and nrDNA ITS analyses support the hypothesis of an early separation of Larix into a North American and a Eurasian clade, which is congruent with the results of previous allozyme and very recent AFLP analyses. The unexpected close relationship between North American larches and the short-bracted species L. gmelinii in East Asia, based on the 4CL gene tree, may stem from lineage sorting.     

中国东北落叶松属3种植物潜在分布对气候变化的敏感性分析

该文在东北地区多年平均的年均温、年降水分布图,海拔高程图、坡度图、坡向图和植被图的基础上,使用地理信息系统和Logistic回归模型的结合,预测3种落叶松(Larix sp.)的“气候-地形”潜在分布区。预测精度用敏感性、指定度和总正确率进行评价,3个树种的敏感性为61%~88%,指定度为80%~99.8%,总正确率为80%~99.8%。年均温、年降水和海拔是控制3种落叶松分布的主要环境因子。采用5种气温变化方案(+1 ℃、+2 ℃、+3 ℃、+4 ℃和+5 ℃)和6种降水变化方案(-30%、-20%、-10%、+10%、+20%和+30%),预测气候变化对各个树种潜在分布的影响,探索不同的树种对气候因子的敏感性。结果表明,气温每上升1 ℃,兴安落叶松(Larix gmelinii)将减少12%;长白落叶松(Larix olgensis var. changpaiensis)将增加23%;华北落叶松(Larix principis-rupprecntii)将增加500%。降水每增加10%,兴安落叶松将减少12.5%;长白落叶松将增加64%;华北落叶松将减少15%;随气候的“暖干化"(+5 ℃,-30%),兴安落叶松将向西北方退缩100 km左右;长白落叶松向西北方扩展100 km左右;华北落叶松将向东北方扩展800 km左右。随气候的“暖湿化"(+5 ℃,+30%),兴安落叶松将向西北退缩400 km左右;长白落叶松将向西北方扩展550 km;华北落叶松将向东北方扩展320 km左右。     

大兴安岭兴安落叶松森林不同林型AMF分布特性

为了初步了解内蒙古大兴安岭兴安落叶松森林生态系统丛枝菌根真菌(AMF)多样性状况, 调查了5种落叶松林型和火烧迹地土壤中AMF状况。从90份土样中共分离到AMF 4属53种, 其中无梗囊霉属Acaulospora 25种(47.17%), 球囊霉属Glomus 23种(43.40%), 此二属为优势属, 内养囊霉属Entrophospora 4种(7.55%), 巨孢囊霉属Gigaspora 1种(1.89%)。杜香落叶松林的优势种为浅窝无梗囊霉A. lacunosa; 草地落叶松林没有优势种, 最常见种为浅窝无梗囊霉A. lacunosa; 柴桦落叶松林的优势种为一种无梗囊霉Acaulospora sp. 3和缩球囊霉G. constrictum; 落叶松皆伐林的优势种为刺无梗囊霉A. spinosa; 落叶松渐伐林的优势种为一种球囊霉Glomus sp. 3; 火烧迹地的优势种为刺无梗囊霉A. spinosa。5种林型中以柴桦落叶松林的孢子密度(41.00个/50 g 风干土)、物种丰富度(12.66种/土样)、多样性指数(H = 2.12, D = 0.85)都为最高。孢子密度与有机质含量呈明显正相关(r = 0.956*), 物种丰富度与速效磷含量呈明显的负相关(r = -0.899*)。     

The diversity of chloroplast microsatellite loci in Siberian fir (Abies sibirica Ledeb.) and two Far East fir species A. nephrolepis (Trautv.) Maxim. and A. sachalinensis Fr. Schmidt

The genetic variability in 29 populations of Abies sibirica, three of A. nephrolepis, and seven of A. sachalinensis was studied using SSR markers of chloroplast DNA. Stable amplification and polymorphic products were obtained using primer pairs Pt71936 and Pt30204 (with nine and forteen alleles, respectively) of 10 pairs. Totally, 70 haplotypes were found, 43 in A. sibirica, 49 in A. sachalinensis, and 31 in A. nephrolepis. The highest values of genetic diversity parameters were observed in A. sachalinensis, and the lowest in A. nephrolepis. The Siberian fir differs from Far East species by the uneven multimodal frequency distributions of allele length in both cpSSR loci, which is explained by the presence of few separated from each other dominating haplotypes. This fact indicates that A. sibirica and the Far East species have different demographic histories. In A. sibirica, the proportion of diversity between populations in the total genetic diversity, calculated taking into account the differences between haplotypes (R(ST)) was 8.34% and 4.42% without accounting for haplotypes differences (R(ST) > G(ST), P= 0.01). The pairwise G(ST) correlate significantly with geographic distances between the populations A. sibirica and with genetic distances D calculated from allozyme data. No such correlations were found with the R(ST) parameter. The results of cpSSR variability analysis strongly support the conclusions inferred from allozyme data: several geographic groups of comparatively genetically close populations are identified, which may be explained by the invasion of colonization of the present-day Siberian fir range.     

Syntaxonomy of vegetation of the Svyatoi Nos peninsula, Lake Baikal 2. Forests and krummholz in comparison with other regions of northern Buryatia

Using the Braun-Blanquet approach, 7 plant communities of forests and 3 communities of krummholz were distinguished on the Svyatoi Nos Peninsula on the eastern coast of Lake Baikal. Dominant species of these communities areAbies sibirica, Larix sibirica, Pinus sibirica, P. sylvestris, P. pumila andBetula divaricata. The data from Svyatoi Nos were combined with all the available data from the northern part of the Republic of Buryatia (289 relevés) and classified into 23 communities. These have been assigned to the following alliances:Aconito rubicundi-Abietion sibiricae—floodplain forests with tall forbs and the relict occurrence of a few nemoral species,Pino sibiricae-Laricion sibiricae—mesic forests with (sub-Atlantic) boreal species and abundant mosses,Vaccinio-Pinion pumilae—krummholz communities of NE Asian distribution,Cladonio stellaris-Laricion gmelinii—Larix gmelinii dominated open forests on permafrosts with NE Asian distribution, andHieracio umbellati-Pinion sylvestris—xeric forests with southern Siberian species. Phytogeographical affinities of these alliances are discussed and a system of high-ranked syntaxa (orders, classes) is proposed for the northern Buryatian forests and krummholz.