福建省梨地方品种的遗传多样性研究

利用叶绿体DNA非编码区序列acc D-psa I和17对SSR引物对原产于福建省的49个梨地方品种的遗传多样性进行分析,旨在为育种利用提供参考。获得49份福建地方品种的acc D-psa I序列,并检测到4个多态性位点,包含5个叶绿体单倍型(Hap1~Hap5),其中核苷酸多态性(Pi)为0.00139,单倍型多样性(Hd)为0.660。TCS网络图显示Hap5是最古老的单倍型,其仅在两个样品中检测到。17个SSR位点共检测到211个等位基因位点,有效等位基因数(A)为5~23个,平均值为12.41;观察杂合度(Ho)和期望杂合度(He)的平均值分别为0.5802和0.7549;17个SSR位点的Shannon’s信息指数(I)值为0.5830~2.7683,平均值为1.8661,表现出较高的遗传多样性。基于Nei和Li的遗传距离的邻接法(Neighbor-Joining,NJ)将49份样品聚为9个组,其中大部分聚类结果与单倍型类型表现的亲缘关系较为一致。叶绿体单倍型和SSR多态性位点信息证实福建地方品种具有较为丰富的遗传多样性。     

杧果种质遗传多样性的RAPD分析

对杧果不同生态型、不同胚性、不同果形与果色的38份品种和1个近缘种—扁桃进行了RAPD分析,19个引物在39份种质中共扩增出223条带,其中多态性带为196条,多态性带的百分率为87.89%,表明品种间存在着广泛的遗传基础。利用UPGMA进行聚类分析,在相似性系数0.755的水平上将38个品种分成3组,该结果与传统上以胚型为依据进行品种类群划分比较吻合。发现了多个与胚性密切相关和1个与果皮颜色密切相关的RAPD标记,并就部分品种的系谱关系、胚性和果皮颜色的遗传进行了探讨。     

云南野生兰属主要种间亲缘关系的AFLP分析

 采用AFLP技术对云南省兰属的14个种和3个变种中的38份样本进行了亲缘关系分析。16对AFLP引物扩增的条带聚类结果表明, 云南省国兰遗传多样性非常广泛, 相同品种间的不同个体扩增出的条带模式相差很大。依据AFLP数据, 在相似系数0.58的水平下, 38个兰花样品分成3组: 莲瓣兰、春剑、惠兰、寒兰分为第1组, 建兰、豆瓣兰、春兰, 墨兰、虎头兰、西藏虎头兰、大雪兰、碧玉兰、文山红柱兰、长叶兰和兔耳兰分为第2组, 送春和蜜蜂兰分为第3组。     

Application of genomic in situ hybridization for phylogenetic study between Mangifera indica L. and eight wild species of Mangifera

The phylogenetic relationship between mango (Mangifera indica L.) and eight wild species of Mangifera were analyzed by comparing signal intensity of genomic in situ hybridization (GISH) on somatic metaphase chromosomes of M. indica, using labeled DNA of eight wild Mangifera species. The eight wild species were divided into four groups based on intensity and number of hybridization signals on chromosomes of M. indica in GISH analyses. The probe of Mangifera sylvatica Roxb. gave the highest intensities on the chromosome of M. indica, indicating a close relationship between M. indica and M. sylvatica. For the other species, classification of GISH was comparable to that of the phylogenetic analysis using AFLP markers, as previously reported ( Eiadthong et al., 2000). This suggested a possibility that GISH analysis can be effectively used in the classification of Mangifera species.     

Assessing Rosa persica genetic diversity using amplified fragment length polymorphisms analysis

The genetic diversity among 128 Iranian Rosa persica (R. persica) accessions in the different populations was analyzed. Amplified fragment length polymorphisms (AFLP) technique was used to produce 171 polymorphic fragments. The number of polymorphic loci ranged from 101 to 147 and the polymorphism information content (PIC) varied from 0.289 to 0.073, with an average of 0.16. This shows extreme variability and genetic diversity among the studied R. persica populations. An indirect estimate of the number of migrants per generation (Nm = 0.376) indicated that gene flow was relatively low among populations of the species. Cluster analysis using the UPGMA method grouped all accessions into six clusters. The results did not show relative agreement with the genotypes’ region of origin. Based on an analysis of molecular variance, 48% of the genetic variation of R. persica was within population and 52% was among populations. The present analysis revealed that Iranian R. persica genotypes are highly variable and genetically distinct from their origins. The apparent unique nature of the R. persica genotypes revealed by our results supports the case for the implementation of more intense characterization and conservation strategies, and provides useful information to address breeding programmes and germplasm resource management in Rosa spp.     

Genetic relationships in Eriobotrya species as revealed by amplified fragment length polymorphism (AFLP) markers

Although most of the species in Eriobotrya originated in China there are few studies on the genetics and genetic relationship of this genus. The aim of the present study was to clarify genetic relationships among 18 Eriobotrya accessions from China using amplified fragment length polymorphism (AFLP). Two close relatives Raphiolepisindica (L.) Lindl. and Photiniaserrulata Lindl. were used as outgroups. The results showed that 5 selected AFLP primer combinations amplified 297 scorable bands, of which 282 were polymorphic, yielding a polymorphism rate of 95%. Genetic similarity coefficient among Eriobotrya accessions ranged from 0.82 (between E. bengalensis Hook.f. and E. bengalensis forma angustifolia Vidal) to 0.41 (between E. serrate Vidal and E. deflexa Nakai) indicating substantial genetic variations in the Eriobotrya accessions evaluated. The unweighted pair-group method of arithmetic averages (UPGMA) cluster analysis, based on genetic similarity coefficient, produced a dendrogram which grouped 20 accessions into three main clusters. The result of cluster analysis was generally in agreement with the known taxonomic grouping. Furthermore, the clustering of the 18 accessions of Eriobotrya was consistent with systematic classification based on morphological characteristics.     

百合遗传多样性及亲缘关系的RAPD分析

 对百合野生种及栽培品种共60份材料进行了RAPD分析, 22条随机引物共扩增出224条带,其中163条为多态性带, 多态率为72.77%。UPGMA分类结果将60份百合材料分为两大类群, 第1类群为铁炮与亚洲百合杂交系(L /A) 、野生种、亚洲系百合(A) 、喇叭百合杂交系(T) 及东方与喇叭百合杂交系(O /T) 的聚合, 这一类群在阈值0.668处又被分为两个亚类群; 第2类群为1 份野生种(L. speciosum ) 及铁炮系百合(L) 和东方系百合(O) 的聚合, 其中东方系百合在阈值0.746处又被分为两个亚类群。根据此分类结果, 进行了类群间亲缘关系及品种起源形成分析, 60份百合材料被划分为14个群组。经统计分析, 各群组之间的遗传相似系数与遗传距离的变化呈现相反的趋势。     

43份云南野生枇杷种质遗传多样性与亲缘关系分析

应用SSR、SRAP等2种分子标记方法,分析了43份云南野生枇杷种质的遗传多样性及其与部分栽培品种、野生近缘种的亲缘关系。结果表明：云南野生枇杷种质具有较丰富的遗传多样性,其多态性位点百分数为91.32%,平均期望杂合度为0.3165,平均香农多样性指数为0.4753;在相似系数0.751水平上,43份材料可被划分入4个大类,其中类Ⅲ在相似系数0.816处可细分为6个亚类;主成分分析则更为直观地展现了种质间的亲缘关系。聚类结果与种质类型相关,并呈现出一定的地域性分布规律。结合形态学特征,鉴定该批云南野生种质以栎叶枇杷种内类型居多,甚至有出现变种的可能。     

Genetic analysis of Tunisian fig (Ficus carica L.) cultivars using amplified fragment length polymorphism (AFLP) markers

Genetic diversity of forty fig cultivars collected from five regions in Tunisia was investigated using amplified fragment length polymorphism (AFLP). A total of 342 reproducible bands amplified with six AFLP primer combinations were obtained. The high percentage of polymorphic bands (%PB) of 97.5 and the resolving power (Rp) collective rate value of 143 were scored. In addition, the polymorphism information content (PIC) values varied from 0.61 to 0.87 with an average of 0.77. Although cluster (UPGMA) and principal components analyses indicate that the cultivars’ clustering made independently both from the geographical origin, horticultural classifications and/or from the sex of trees. In addition, the observed variation suggests considerable differentiation among fig cultivars. The present data supports the common origin of the fig cultivars. Analysis of molecular variance (AMOVA) revealed that average Φ_ST value overall loci was 0.026, and the overall distribution pattern of molecular variation indicated that about 97.43% of the total variance was accounted by the within-region variance component. The remaining 2.5% (P < 0.001) of the variation was founded among cultivars of the prospected regions. Our results proved that AFLP markers are useful for germplasm discrimination as well as for investigation of fig patterns variation. The information may be useful to define conservation management program.     

梨属种质资源的RAPD分析

 对梨属40 个品种及类型进行了RAPD 扩增, 根据相似系数进行UPGMA 法聚类,将起源于欧洲的西洋梨与起源于中国的3 个种明显区分开, 起源于中国的3 个种虽未完全各自聚类, 但各材料间都有不同的遗传距离, 证明RAPD 技术可作为梨种质分类鉴定的依据。     

Analysis of genetic variation in eggplant and related Solanum species using sequence-related amplified polymorphism markers

Collection and characterization of all sorts of germplasm resources are required for the development of new cultivars. Molecular characterization is more reliable than morphological characterization. Here, we employed sequence-related amplified polymorphism (SRAP) markers to evaluate genetic variation in a diverse collection of 56 Solanum accessions. Fifty-five SRAP primer combinations were used and a total of 635 polymorphic bands were observed. Cluster analysis by the unweighted pair-group method with arithmetic averages based on similarity matrices indicated that there were three clusters: (i) S. melongena; (ii) S. aethiopicum; (iii) S. surattense. The coefficients of genetic similarity among all the accessions ranged from 0.04 to 0.96 with an average of 0.73, and averaged 0.78 among S. melongena accessions originated from China, indicating extensive genetic variation. These results demonstrated that SRAP can be efficiently used to estimate genetic diversity and analyze phylogenetic relationship.     

Weak relationships between landscape characteristics and multiple facets of stream macroinvertebrate biodiversity in a boreal drainage basin

Variability in biodiversity is often assessed based on species richness, and this adherence to a single index has been typical in studies of ecology, biogeography, and conservation in the past two decades. More recent studies have suggested that species richness alone is insufficient as a measure of biodiversity, mainly because it is not necessarily correlated with other measures of biodiversity. We examined (1) if nine indices embracing species diversity, functional diversity, and taxonomic distinctness of stream macroinvertebrate assemblages show congruent patterns, and (2) if these indices show similar relationships to landscape characteristics. Not all indices varied similarly and were thus not significantly correlated. There were three principal components that effectively described variation in the correlation structure of the nine indices. These three components were: (1) diversity and evenness indices, (2) two indices of taxonomic distinctness, and (3) species richness and functional richness. Four of the nine biodiversity indices examined showed no significant relationships to landscape-catchment characteristics, and even the significant correlations between the remaining five indices and explanatory variables were rather weak. However, species richness showed a rather strong quadratic relationship to catchment area. Our study provided a number of suggestions for future biodiversity studies at the landscape scale. First, given that different indices describe different components of biodiversity and are not strongly correlated, multiple indices should be considered in any study describing stream biodiversity. Second, despite the study was restricted to near-pristine streams, all indices showed considerable variation. Thus, this natural variability should be accounted for prior to the examination of anthropogenic effects on stream biodiversity. Third, landscape-catchment variables may have only limited value in explaining variability in biodiversity indices, at least in regions with no strong anthropogenic gradients in land-use.     

Phylogenetic study and molecular identification of 31 Dendrobium species using inter-simple sequence repeat (ISSR) markers

The genetic diversity of the genus Dendrobium is not well known and the phylogenetic relationship of Dendrobium species are mainly determined by studies of the comparative vegetative anatomy and plant systematics. In the present study, we used the technique of inter-simple sequence repeats (ISSRs) to evaluate genetic diversity and phylogenetic relationship among 31 Dendrobium species from Yunnan region of China. In total, 2368 bands were amplified by 17 ISSR primers, resulting from 278 ISSR loci with 100% polymorphism at genus level. Thirty-one species were unequivocally distinguished based on ISSR fingerprinting. Species-specific ISSR markers were identified in nine of 31 tested Dendrobium species. Unweighted pair-group mean analysis (UPGMA) showed that 31 Dendrobium species were grouped into six clusters, indicating the genus was polyphyletic with several well-supported lineages. The high polymorphism and reliable amplification across species demonstrated the utility of ISSR marker for species diagnosis and genetic diversity study of the genus Dendrobium.     

豫西地区茄科作物土壤镰孢菌的种群多样性 分析

为明确豫西地区茄科作物土壤镰孢菌菌株间的系统发育关系,对从豫西地区17 个县、市
采集的32 份土壤样品中分离得到的96 株镰孢菌进行形态学鉴定及EF-1α 序列分析。结果表明：供试
镰孢菌分属于5 个种,位于系统发育树的5 个分支上,分别为尖孢镰孢菌（F. oxysporum）、藤仓镰孢菌
（F. fujikuroi）、轮枝镰孢菌（F. verticillioide）、F. incarnatum 和F. incarnatum-equiseti species complex。
其中尖孢镰孢菌（F.oxysporum）的分离频率最高,为45.83%,在所调查的4 种茄科作物土壤中均有分布;
而F.incarnatum-equiseti species complex 的分离频率最低,仅在马铃薯和番茄土壤中存在。不同地区茄科
作物土壤镰孢菌种群存在差异。     

Effectiveness of SSR molecular markers in evaluating the phylogenetic relationships among eight Actinidia species

The aim of the present study is to evaluate a set of microsatellites and their effectiveness in determining the phylogenetic relationships among Actinidia species. A set of 14 genotypes belonging to eight Actinidia species were subjected to PCR using SSRs as molecular markers. The PCR products were analyzed on denaturing polyacrylamide gels. The discriminating ability of SSRs was based on the number of alleles and the indices DI, I and PIC. All SSR primer pairs were polymorphic and identified a total number of 61 alleles corresponding to an average of 7.8 alleles per locus. Data showed that the di-nucleotide microsatellites were more polymorphic, than the tri-nucleotide and penta-nucleotide, and were more efficient in establishing genetic similarities. The genetic similarity of the genotypes calculated with Jaccard and/or Dice similarity coefficients varied from 0.100 to 0.579, indicating a broad genetic base for the genetic material tested. Both similarity matrices clustered either with UPGMA or NJ, produced similar topology with minor clustering differences among genotypes. Thus, the eight species were clustered in two main groups and each main group in two subgroups. Data showed a close genetic relationship among Actinidia chinensis and Actinidia deliciosa species. The same conclusions were, also, drawn using the principal coordinate analysis.     

甘肃中部梨资源遗传变异和亲缘关系的SSR分析

用6对SSR特异性引物对甘肃中部46个梨品种或类型的遗传变异和亲缘关系进行了分析,结果表明,SSR位点的期望杂合度为0.446～0.738,平均为0.639,显示了良好的品种鉴定能力。采用UPGMA聚类分析法构建的系统树将供试梨品种或类型分为7个大组:木梨组、白梨组、秋子梨组、褐梨组、西洋梨组和2个可能以秋子梨为基本种而形成的复杂的种间杂种组。唯一的砂梨品种黄花梨包含在白梨组中。新疆梨的5个品种没有独立成组,而是分别包含在木梨、白梨及秋子梨组中。一些原来根据形态学无法归类的品种和类型分别和木梨、白梨和西洋梨聚合在一起,显示出和这些梨系统的亲缘关系;木梨虽然采集地相对集中,但也显示出丰富的遗传多样性。     

Genetic diversity and phylogenetic relationships of Prunus microcarpa C.A. Mey. subsp. tortusa analyzed by simple sequence repeats (SSRs)

Prunus microcarpa C.A. Mey. subsp. tortusa is a deciduous shrub well adapted to severe winter and dry-hot summer conditions. As the first step to explore the genetic and horticultural potential of P. microcarpa C.A. Mey. subsp. tortusa, we used SSRs to elucidate the genetic variation within its populations dispersed in upper Mesopotamia. We also investigated its phylogenetic relationship with economically important Prunus species; almond, apricot, sweet cherry, peach and plums. Using 47 amplifying SSR primer pairs, 63 P. microcarpa C.A. Mey. subsp. tortusa genotypes sampled from five locations and 15 cultivars belonging to other Prunus species were assayed. The cross-species transportability of SSRs was 96% indicating a high degree of homology between P. microcarpa C.A. Mey. subsp. tortusa and the other Prunus species. The genetic distance between P. microcarpa C.A. Mey. subsp. tortusa genotypes belonging to a particular geographic site was lower than that between genotypes of different geographic origins. Cluster analysis differentiated P. microcarpa C.A. Mey. subsp. tortusa genotypes according to their geographic sites and separated them from the other Prunus species. P. microcarpa C.A. Mey. subsp. tortusa and sweet cherry, the subgenus Cerasus, were located in the same major cluster, the other Prunus species, belonging to the subgenera Amygdalus and Prunus, were located in another one. The analysis of molecular variance (AMOVA) revealed that genetic variation among individuals within populations (59.10%) was much higher than among Prunus groups (29.28%) and among P. microcarpa C.A. Mey. subsp. tortusa populations of different geographic sites (11.61%). The results indicate a substantial genetic diversity in P. microcarpa C.A. Mey. subsp. tortusa and the need of exploring a wider area to increase the chance of finding a particular genotype.     

Genetic diversity and relationships of lotus (Nelumbo) cultivars based on allozyme and ISSR markers

Genetic diversity and genetic relationships of lotus (Nelumbo Adanson) cultivars were evaluated using allozyme and ISSR markers. The samples used covered 11 accessions of possible hybrids between Nelumbo nucifera and Nelumbo lutea and 92 accessions of N. nucifera including 69 flower lotus, 13 rhizome lotus, 5 seed lotus and 5 wild lotus. For allozyme studies, a total of 31 alleles at 23 loci of 18 enzyme systems were detected of which 5 (21.7%) loci Aat, Idh, Mdh-2, Pgd, Sod were polymorphic. The loci of Aat and Idh included two alleles, Mdh-2, Pgd and Sod included three alleles. Eighteen genotypes were detected with the 13 alleles of the 5 polymorphic loci. The parameters of average allele number, observed heterozygosity, expected heterozygosity and Shannon information index of 92 N. nucifera samples were 1.35 ± 0.71, 0.06 ± 0.21, 0.05 ± 0.14, 0.10 ± 023, respectively. Thirteen ISSR primers generated 93 loci, of which 37.63% were polymorphic across all samples. The percentage of polymorphic loci, average allele number, expected heterozygosity and Shannon information index of 92 N. nucifera samples were 26.67%, 1.30 ± 0.46, 0.10 ± 0.18 and 0.15 ± 0.25, respectively for the ISSR data. The ‘Bottleneck effect’ and rapid propagation of clones after the ice ages may explain the low genetic diversity of lotus. The dendrograms based on ISSR and allozymes were not congruent. Based on the ISSR data, the 103 samples were divided into the N. nucifera group (Group I), and the group containing inter-specific hybrids between N. nucifera and N. lutea (Group II). The flower lotus, rhizome lotus, and seed lotus each has multiple sources of origin. Plant size, a criterion commonly used in the classification of cultivars of lotus, is not correlated with genetic variation. Flower color is correlated with the cultivar classification to some degree, but its variation is complex in the hybrids.     

应用SSR标记进行部分黄肉桃种质鉴定和亲缘关系分析

以116份黄肉桃种质和19份其它桃或桃近缘种种质为试材,利用定位于李属参考图谱上的SSR标记,进行遗传多样性评价及亲缘关系分析。SSR扩增结果表明,筛选出的28对SSR引物共扩增出206个等位基因,其中多态性等位基因159个（占76.56%）。聚类结果表明,在相似系数为0.82时,黄肉桃资源在聚类图上呈两组：美洲、欧洲和亚洲育成黄桃品种聚为一组（Ⅰ）,中国地方黄桃品种中唯‘西安杏瓤桃’和‘天津黄肉’出现在这一组;来源于云南、华北、西北地区的中国地方黄桃品种聚为另一组（Ⅱ）。在相似系数为0.87时,育成黄桃品种（Ⅰ）分为8个亚组,美洲育成品种分布在所有8个亚组中,欧洲育成品种分布在Ⅰ-2、Ⅰ-3和Ⅰ-4亚组,而亚洲育成品种仅分布在Ⅰ-3和Ⅰ-4亚组;亲本相同的育成品种在聚类图中临接或出现在较近的位置,育成品种的聚类结果与品种的系谱关系基本吻合。在相似系数为0.87时,中国地方黄桃品种分为7个亚组,西南黄桃和西北黄桃存在一定的组群界限,来自西南的黄桃地方资源主要分布在Ⅱ-1和Ⅱ-5亚组,而来自西北的黄桃地方品种主要出现在Ⅱ-2、Ⅱ-4和Ⅱ-7亚组。品种群的聚类结果表明,亚洲育成品种与美洲育成品种间亲缘关系最近,其次为欧洲育成品种;中国地方黄桃品种与育成品种间亲缘关系较远。     

Spatial patterns and drivers of plant diversity in the tropical city of Sanya,China

Drivers of patterns in plant diversity remain poorly understood in tropical cities. Therefore, we investigated diversity within the tropical city of Sanya in Hainan Province of southern China by sampling one to three plots within 154 urban functional units (UFUs) based on six primary and 18 secondary UFUs. To measure diversity, we determined the number of vascular plants (species richness; SR) within each functional unit based on vegetation plots. We computed Faith's phylogenetic diversity (PD_Faith) using a large megatree of plant life. To assess the potential drivers of SR and PD_Faith, we performed multiple regressions using socioeconomic, biophysical, and vegetation management variables. The results showed significant differences in SR and PD_Faith among the six primary UFUs. PD_Faith of cultivated species was significantly higher than PD_Faith of spontaneous species in all UFUs except in the wasteland area. Management measures were better predictors of SR and PD_Faith than socioeconomic variables. The best predictor of SR and PD_Faith of spontaneous species was the management of the urban green space. Our results provide clear guidelines for improved management strategies in Sanya, especially by showing how spontaneous and/or cultivated plant diversity can be encouraged depending on environmental, ecological, and cultural needs. Our work also adds to the presently scarce literature on drivers of urban plant diversity in tropical cities worldwide.