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1.
Wood from 92 trees of Pinus culminicola, Pinus nelsonii, Pinus pinceana and Pinus maximartinezii from nine localities and oleoresin from several trees of Pinus nelsonii from one Iocality were analyzed for monoterpenes by gas liquid chromatography. Monoterpenes of Pinus nelsonii were composed mainly of α- and β-pinenes, while the main constituent of the monoterpenes of Pinus pinceana and Pinus maximartinezii was limonene, present in amounts of about 90 percent. The similarity in composition of the monoterpenes of Pinus pinceana and Pinus maximartinezii strongly supports the contention of Rzedowski [12] of the close evolutionary relation of the two pines. Pinus culminicola wood produced monoterpenes composed mainly of α-pinene, sabinene, terpinolene and limonene, with other monoterpenes occurring sporadically in sizeabie amounts. The variability between individual populations was relatively high, probably due to their long-time isolation by the intervening low-elevation barriers. Appreciable differences were found in compositions of monoterpenes from stem and from twigs of Pinus culrninicola.  相似文献   

2.
Eleven needle traits of two contrasting populations of Pinus uliginosa ( P. mugo complex), one located in a Pinus sylvestris forest, the other isolated from the influence of this species, were compared to quantify the degree of hybridization. Statistically significant differences between the studied populations were found, but both of them differed by a similar degree from P. sylvestris . Surprisingly, the P. uliginosa population surrounded by the P. sylvestris forest, which was expected to consist of individuals with intermediate traits, appeared to be more closely related to P. mugo than those isolated from the direct influence of P. sylvestris . Large differences in the distances between the analysed pair of populations of P. uliginosa and P. sylvestris have not influenced the morphological traits of the species. Gene flow from P. sylvestris to P. uliginosa is possible, but is likely to be small and does not differ compared with populations of P. uliginosa . The decline observed during the last three decades in both populations of the species has not influenced their needle morphological traits.  © 2003 The Linnean Society of London , Botanical Journal of the Linnean Society , 2003, 142, 83–91.  相似文献   

3.
The evolution of five island populations of Green gecko, representing inter- and intra-specific divergence, was studied using biochemical data, scalation and shape. The data were numerically analysed using ordination analyses for the phenetic classification and Wagner trees to hypothesize the phylogeny. These studies revealed three phenetic groups corresponding to three mono-phyletic lineages. The numerical analysis of morphological data agreed with the numerical analysis of biochemical data. It is concluded that the classification based on biochemical affinities differed from the previous classification based on conventional analysis of morphology due to methodological and philosophical differences rather than differences between morphological and biochemical evolution.
The ordination analyses were very congruent between data sets (biochemical, shape, scalation, total) and the Wagner trees were generally congruent between data sets. Some Wagner trees based on scalation data were incongruent. The phenetic and cladistic classifications corresponded to each other but differed from the conventional classification. The phylogenetic analysis of the total data set indicated that the three specific lineages showed relatively equal anagenesis. However, anagenic divergence differed markedly between character types. It is suggested that a range of character types be used when studying anagenesis.  相似文献   

4.
Heteroblastic development in pine seedlings includes extreme morphological changes with still unclear adaptive and evolutionary significance. In particular, Mediterranean and Eurasian pines (section Pinus) living in the Mediterranean basin seem to follow quite distinct developmental trajectories at the seedling stage. Aiming to confirm this ontogenetic differentiation we performed a nursery experiment with seedlings of five Mediterranean pines (Pinus pinaster, P. brutia, P. halepensis, P. pinea and P. canariensis) and three Eurasian pines (P. sylvestris, P. uncinata, and P. nigra subsp. salzmannii), also including P. radiata as an outgroup. After destructive analyses at two harvest times (9 and 32 weeks), we found sharp differentiation between Mediterranean and Eurasian pines in a combination of traits linked to shoot heteroblasty. In particular, Mediterranean pines showed a marked delay in the proportion of adult needles to total needles in the shoot compared to Eurasian species, especially at the second harvest. However, two Mediterranean pines, P. pinaster and P. brutia showed a slightly higher proportion of secondary needles, and a higher rate of budset at a more advanced stage (68 weeks) compared to the other three Mediterranean species. Meaningfully, the outgroup P. radiata was the only species combining a high proportion of adult foliage since the first harvest with a delayed formation of the first terminal bud. We discussed the adaptive significance of these findings at the light of species’ climatic niches and life histories.  相似文献   

5.
Panzerina lanata ( L. ) Sojak complex is distributed on the Mongolia plateau. Twenty-two populations representing six species in the complex: P. lanata, P. alaschanica, P . kansuensis , P . albescens , P. argyracea and P . parviflora , were sampled throughout the range of the complex including 2 provinces and 3 autonomous regions. Extensive studies were carried out by comparison of wild collection and cultivation, and morphological analysis based on character evaluation and multivariate procedures. It is showed that there exists considerable phenotypic plasticity in some morphological characters, especially those of the root, caudex and leaf. However, the characters of flowers, capsules and seeds were less influenced by environments. The character analysis indicates that some characters, which were used to distinguish taxa of the complex, for example the degree of leaf division, the morphology of calyx and so on, are continuous in a wide range in wild populations. Some “species” in the complex described according to the differences in those characters are only extreme individuals within their continuous variation. As a result, the above analysis and their geographical distribution suggest that P. alaschanica , P. kansuensis , P. albescens be actually the extreme individuals within P. lanata. In the same way, P. argyracea is invalid. The principal components analysis of 11 morphological characters on the individuals from 22 populations shows no differences. Thus, this paper considers that characters such as nutlet with or without wart, size of corolla exceeding calyx or not and dry flowers with or without colour, may be used to distinguish taxa of this complex. From the above analysis, it is indicated finally that the six species in this complex are better reduced taxonomically into two species, namely P. lanata (L.) Sojak and P. parviflora (C. Y. Wu et H. W. Li) Y. Z. Zhao, the difference of two species as follow: Nutlet surface smooth; corolla, 2~2.2 cm long; flower white and unchanging after dry .......................................................... Panzerina parviflora Nutlet surface tuberculate; corolla, 2.5~ 4 cm long; flower white, but becoming yel- lowish after dry ....................................................... P. lanata  相似文献   

6.
Pinus densata is distributed on the Tibetan Plateau, where it forms extensive forests at high elevations. Genetic studies have provided evidence that P. densata originated through hybridization between P. yunnanensis and P. tabuliformis. To clarify the relationships among these pines, and assess their reproductive fitness in their respective habitats, we conducted a comparative analysis of eight cone and seed morphometric traits and six reproductive traits in them. Among the eight morphometric traits examined, six appeared to be intermediate in P. densata between those of P. yunnanensis and P. tabuliformis. There were significant differences among the three pines in all of the morphometric traits, and P. densata showed greater variability in these traits than the other two pines. In contrast to the morphometric traits, the reproductive traits (including the proportions of filled and empty seeds, ovule abortion rate, seed efficiency, meiotic abnormalities during microsporogenesis and pollen viability) differed little among the three pines, indicating that they have similar overall rates of effective pollination and fertilization in their respective natural environments. Despite their location on the high plateau, natural populations of P. densata appeared to have normal levels of reproductive success, comparable to those of the two parental species in their natural habitats. This study provides empirical data characterizing the reproductive success and adaptation of a stabilized homoploid hybrid in a novel habitat that is ecologically and spatially inaccessible to its parental species. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

7.
The dwarf mountain pine (Pinus mugo) and the Pyrenean pine (P. uncinata) constitute a pair of closely related coniferous taxa of poorly resolved evolutionary history and affinity, which inhabit numerous stands scattered over subalpine environments of European mountain ranges. The aim of the study was to investigate their phylogeography and mutual relationships, shedding new light on their taxonomy and the past of the alpine flora. Previous evolutionary reconstructions of the mountain pines relied mainly on bi‐parentally or paternally inherited markers that quickly homogenize between populations, showing rather shallow and recent differentiation of gene pools. Therefore, to contrast these pictures, we analyzed diversity and differentiation within a large set of new mitochondrial loci, inherited in maternal line and distributed by seeds at short geographical distances. Samples of the taxa were taken from 27 natural populations representing their range‐wide distributions—17 populations of P. mugo and 10 of P. uncinata. All markers appeared polymorphic, providing a total of 31 multilocus haplotypes. Two of the loci proved to be species‐diagnostic and nearly fixed between analyzed samples. Distribution of mitotypes indicate that allopatric populations of the taxa constitute separate mitochondrial haplogroups, and the two mountain pines have independent evolutionary history. However, introgression of P. mugo mitotypes by P. uncinata specimens revealed in the species contact zone in Western Alps shows that their speciation is not fully completed.  相似文献   

8.
Song BH  Wang XQ  Wang XR  Ding KY  Hong DY 《Molecular ecology》2003,12(11):2995-3001
Sequence and restriction site analyses of the paternally inherited chloroplast rbcL gene and maternally inherited mitochondrial nad1 fragments from the same set of populations and individuals were used to investigate cytoplasmic composition and population establishment of Pinus densata, a diploid pine that originated through hybridization between P. tabuliformis and P. yunnanensis. Two variable sites and three chlorotypes (TT, TC and GC) were detected on the rbcL gene of the three pines. P. densata harboured the three chlorotypes, two of which (TT, GC) were characteristic of the parental species, respectively. The third chlorotype (TC) was distributed extensively in seven of the 10 P. densata populations analysed, and might represent a mutation type or have been derived from an extinct parent. The distribution of chlorotypes, together with that of mitotypes, indicated that significant founder effect and backcross happened during the population establishment of the hybrid pine. P. tabuliformis and P. yunnanensis had acted as both mother and father donors, i.e. bi-directional gene flow existed between the two parental species in the past. Population differentiation of P. densata is high, as detected from the cytoplasmic genomes: GST = 0.533 for cpDNA and GST = 0.905 for mtDNA. The differences in cytoplasmic composition among the hybrid populations suggest that the local populations have undergone different evolutionary histories.  相似文献   

9.
云南松居群内雄球花多态性   总被引:5,自引:0,他引:5  
本文观察和统计了滇中地区云南松居群内雄球花多态性。 分别统计了当年生新梢上雄球花出现百分率、每个新梢下部聚生的雄球花数、雄球花的色彩、长度和直径。试图揭示云南松居群间和居群内雄球花的变异式样及其分布频率,探讨其变异形成的原因、保持机制和适应意义。研究表明,云南松居群内雄球花多态性显著,居群间多型性也较明显。云南松居群内雄球花多态性是国产松属中最丰富的,也是松属植物中所少见的。雄球花出现百分率、新梢下部聚生的雄球花数、雄球花的大小和色彩等性状,均受多基因控制,呈现连续性变异;云南松居群具有较高的遗传多样性和杂合度是其雄球花多态性和多型性丰富的遗传基础。杂合有利性是造成云南松多态性,特别是平衡多态性的重要原因,同时也使多态性得以保持。云南松林木分布生态环境条件的异质性本身也能导致平衡多态现象。云南松雄球花的变异性与生态环境和林木的年龄相关联,更与居群和林木的遗传结构密切相关。在云南松林木育种和造林过程中,应重视杂种优势和杂合有利性的利用。  相似文献   

10.
Baikal planaria from genus Bdellocephala were typified using rDNA locus coding 5'--end domain of 18S ribosome RNA. Five colour forms of 24 possible variants that differ in diapason 0-1.3% of genotype were determined by comparative analysis of nucleotide sequences. The authors use back colour--one of the most variable and typical character in the given group--to collect material for investigation. It allows to minimize the size of investigation sample and at the same time to cover maximum variability of Bdellocephala. One of the positive result of molecular typification of colour forms was a discovery of unique individuals that belong to new species. Karyological analysis of colour forms shows variations in chromosome numbers that divide planaria into 3 groups (2n = 20, 24, 26). Comparative analysis of morphological and ecological characters and karyotypes of some forms united by the same genotype allows to distinguish them as separate species. Criteria of modern phenetic system of Baikal planaria are discussed.  相似文献   

11.
The hydraulic properties of Pinus pinea, Pinus halepensis and Tetraclinis articulata were studied in a coastal dune area from Eastern Spain. The measured variables include vulnerability to xylem embolism (vulnerability curves), hydraulic conductivity and carbon isotopic discrimination in leaves. Leaf water potentials were also monitored in the three studied populations during an extremely dry period. Our results showed that roots had always wider vessels and higher hydraulic conductivity than branches. Roots were also more vulnerable to xylem embolism and operated closer to their hydraulic limit (i.e., with narrower safety margins). Although it was not quantified, extensive root mortality was observed in the two pines during the study period, in agreement with the high values of xylem embolism (> 75%) predicted from vulnerability curves and the water potentials measured in the field. T. articulata was much more resistant to embolism than P. pinea and P. halepensis. Since T. articulata experienced also lower water potentials, safety margins from hydraulic failure were only slightly wider in this species than in the pines. Combining species and tissues, high resistance to xylem embolism was associated with low hydraulic conductivity and with high wood density. Both relationships imply a cost of having a resistant xylem. The study outlined very different water-use strategies for T. articulata and the pines. Whereas T. articulata had a conservative strategy that relied on the low vulnerability of its conducting system to drought-induced xylem embolism, the two pines showed regulatory mechanisms at different levels (i.e., embolism, root demography) that constrained the absorption of water when it became scarce. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

12.
A species-specific marker of cpDNA (paternally inherited in pines) was used to verify the hybrid origin of seedlings from controlled reciprocal crosses between Pinus sylvestris and P. mugo. A very low degree of compatibility between those two species has been revealed. In the three consecutive years of experiments, no filled seeds were obtained in the combination with P. mugo as the seed parent. From P. sylvestris as the seed parent and P. mugo as the pollen donor, we succeeded to obtain four filled seeds (about 1 %), but only in one year. The seedling obtained from the seeds had cpDNA haplotypes specific to P. mugo, which proves their hybrid origin. This method enables verification of the result of controlled crosses. The importance of the results has been discussed in the aspect of postulated natural hybridisation in sympatric populations of the two species.  相似文献   

13.
The phenotypic differentiation of relic P. sylvestris in southern Europe and southwestern Asia was verified using thirty-two populations sampled from the Iberian Peninsula, Massif Central, Balkan Peninsula, Crimea and Anatolia. Twenty-one morphological and anatomical needle traits and 18 cone morphological characteristics were examined to describe the population diversity and differentiation. The needle characters were not correlated to those of cone. The differences between regions were significant based on 12 needle and 9 cone characteristics, suggesting spatial isolation. The differentiation between the Iberian and Anatolian populations was the highest, which indicates the isolation by distance. The high level of morphological differentiation was also found among Iberian populations, supporting the already known complex history of the species in that region. Populations within other regions were differentiated at lower levels; however, the West Anatolian populations differed morphologically from the eastern ones. The described pattern of morphological differentiation supports the idea of the long-lasting existence of P. sylvestris in the south-European and Anatolian mountain regions. To conserve this variation, seed transfer between regions in the forest economy should be restricted.  相似文献   

14.
Phylogenetic analysis of plastid DNA restriction site and rearrangement mutations suggests a number of major revisions to taxonomy and phylogenetic concepts in the hard pines. Total genomic DNA from 18 species that sampled all nine subsections was digested with 19 restriction enzymes, blotted, and probed with 70% of the Douglas-fir (Pseudotsuga menziesii) chloroplast genome, or, with clones encompassing the entire chloroplast genome of Pinus contorta. A total of 204 site mutations and five rearrangement mutations were generated, of which 126 were phylogenetically informative. Wagner parsimony analyses revealed 11 clades that were strongly supported by bootstrap and decay index analyses. All North American species except P. resinosa formed a distinct monophyletic group that was strongly separated from the Eurasian species. Within the Eurasian clade subsect. Sylvestres was polyphyletic; its Mediterranean species were closely allied with members of sect. Pinea. Sect. Pinea appeared polyphyletic as well; both species of its subsect. Leiophyllae showed a close affinity to Mesoamerican pines of subsect. Oocarpae in sect. Pinus. Within the North American pines subsects. Ponderosae and Oocarpae were polyphyletic. Despite its shallow fossil record, subsect. Contortae emerged as a sister group to all of the North American pines apart from P. resinosa, which was allied with Eurasian species of subsect. Sylvestres. The remaining North American subsections formed two groups: a poorly resolved clade with subsects. Ponderosae and Sabinianae, and sequentially nested clades represented by: P. radiata; P. taeda; representatives of subsects. Oocarpae and Ponderosae from Mesoamerica, and subsect. Leiophyllae. We present estimates of divergence times for each of these major clades based on molecular clocks calibrated using two hard pine fossil observations.  相似文献   

15.
This study highlights the utility and limitations of multivariate procedures for the analysis and taxonomic interpretation of geographic variation within a complex species. Morphological data from herbarium specimens ofPersoonia mollis (Proteceae) were analyzed by two ordination procedures, multidimensional scaling (MDS) and canonical variate analysis (CVA). Support for the earlier recognition of nine infraspecific taxa was found. However, plots of canonical variate scores against latitute or longitude across parapatric subspecies boundaries revealed unexpected phenetic homogeneity within subspecies with sharp transitions between subspecies. The geographic variation in morphology withinP. mollis can be best described as a mosaic of nine recognisably distinct and internally homogeneous allopatric or parapatric taxa, where neighbouring taxa share surprisingly narrow zones of morphological transition at ecotones. The utility of these procedures was highlighted by the recovery of unexpected patterns of variation. However, questions of rank remain unresolved by phenetic analysis alone.  相似文献   

16.
J Wu  K V Krutovskii  S H Strauss 《Genetics》1998,150(4):1605-1614
We examined mitochondrial DNA polymorphisms via the analysis of restriction fragment length polymorphisms in three closely related species of pines from western North America: knobcone (Pinus attenuata Lemm.), Monterey (P. radiata D. Don), and bishop (P. muricata D. Don). A total of 343 trees derived from 13 populations were analyzed using 13 homologous mitochondrial gene probes amplified from three species by polymerase chain reaction. Twenty-eight distinct mitochondrial DNA haplotypes were detected and no common haplotypes were found among the species. All three species showed limited variability within populations, but strong differentiation among populations. Based on haplotype frequencies, genetic diversity within populations (HS) averaged 0.22, and population differentiation (GST and theta) exceeded 0.78. Analysis of molecular variance also revealed that >90% of the variation resided among populations. For the purposes of genetic conservation and breeding programs, species and populations could be readily distinguished by unique haplotypes, often using the combination of only a few probes. Neighbor-joining phenograms, however, strongly disagreed with those based on allozymes, chloroplast DNA, and morphological traits. Thus, despite its diagnostic haplotypes, the genome appears to evolve via the rearrangement of multiple, convergent subgenomic domains.  相似文献   

17.
Geographic variation was investigated in populations of the day gecko Phelsuma sundbergi from 22 islands in the Seychelles, using multivariate ordination procedures. Multiple group principal components analysis was used to negate ontogenetic variation. Seventy-eight characters from three character systems (body proportions, scalation and colour pattern) were analysed from 349 specimens. Three phenetic aggregations of granitic island populations were detected from the northwestern, northeastern and southern island groups. A comparison of the results from the three character systems analysed separately suggests that the separation of the southern form preceded that of the northern forms. Colour pattern characters reflect this closely, while body proportions and scalation characters follow evolution of body size. The populations of Phelsuma sundbergi on the coralline islands are not well differentiated from the races on the granitic islands, and probably represent recent colonizations or introductions by man.  相似文献   

18.
为了探讨马尾松Pinus massoniana针叶营养物质含量与其对松突圆蚧Hemiberlesia pitysophila Takagi抗性的关系, 选择了不同抗性的10个马尾松家系, 分别测定未受松突圆蚧危害植株与受害植株针叶中可溶性糖、 总糖、 可溶性蛋白、 全N、 游离氨基酸、 粗脂肪等营养物质的含量和总糖/全N等7个指标, 并采用判别分析法分析这7个指标与马尾松家系对松突圆蚧抗性的关系。结果表明:马尾松家系不论是否受松突圆蚧的危害,能明显区别抗性组别的指标都是可溶性蛋白(X3)、全N(X4)和游离氨基酸总量(X7),随抗性的降低, 它们的含量呈上升趋势, 受害植株中上述3个指标的含量低于未受害植株; 受害后, 各指标变化量中能明显区别抗性组别的是全N(X4), 随着植株抗性的降低, 针叶中的可溶性蛋白(X3)、全N(X4)和游离氨基酸总量(X7)的含量变化量减小。据此得出:(1)可溶性蛋白(X3)、全N(X4)和游离氨基酸总量(X7)是与抗性关系最密切的指标, 含量与抗性呈负相关关系,变化量与抗性呈正相关关系;(2)受到危害后, 无论含量或变化量, 7个指标都发生了重要变化, 都表现出与抗性的相关性, 构成了有效判别函数的组成变量;(3)因判别分析方法可以分析各指标的综合作用, 应用该方法分析各营养成分与马尾松对松突圆蚧抗性的关系, 比用方差分析和多重比较方法更有优越性。上述研究结果为抗松突圆蚧马尾松家系的选育及其抗性机理的深入研究, 提供了重要的科学参考价值。  相似文献   

19.
Paeonia (Paeoniaceae) in the Caucasus   总被引:1,自引:0,他引:1  
The taxonomy of the genus Paeonia in the Caucasus has been controversial, with recognized species varying in number from one to 13. The taxonomic history of Paeonia in this area is reviewed (including an analysis of the characters used by previous authors) based on extensive field observations, population sampling and critical examination of a large number of herbarium specimens. The results show that Paeonia may be divided into three groups. The P. intermedia group is known from only a single population. In the P. tenuifolia group, all the characters used for distinguishing the three previously recognized species were found to be polymorphic. In the P. daurica group, petal colour, shape and size of leaflets, and indumentum of leaflets and carpels were used to distinguish nine species, but these characters were found to be polymorphic or continuous in variation, and thus can only be used for infraspecific classification. Thus, three species are recognized: P. intermedia , P. tenuifolia and P. daurica . The last species is further divided into five subspecies: sspp. coriifolia , wittmanniana , mlokosewitschii , macrophylla and tomentosa stat. nov .  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 143 , 135–150.  相似文献   

20.
松属植物遗传多样性研究进展   总被引:17,自引:0,他引:17  
李斌  顾万春 《遗传》2003,25(6):740-748
研究松属遗传多样性的方法涉及表型、同工酶、染色体、DNA等多层面。 松树表型性状变异广泛,其不同树种不同性状的遗传力(或遗传率)均存在差异。到目前为止,同工酶仍是检测松树遗传多样性的最常用方法,一般而言,松属树种群体内等位酶多样性程度高,群体间分化较低,但各树种的情形也不尽相同。松属树种染色体水平的变异很低,其核型高度一致。核DNA组较一般阔叶树大,遗传多样性丰富,但叶绿体等质体DNA则多样性较低。影响遗传多样性的因素很多,其中自身的交配系统和外部的生长环境是影响它的两个主要因素。最后,回顾了松树的起源及其遗传多样性保护策略等方面的研究。 Abstract:The ways of probing genetic diversity of pines involve many aspects,such as morphology,chromosome,isozyme,DNA,etc.The phenotypic characteristics in pines vary widely and the differences of inheritability(h2) are obvious among characteristics and among species.Up to now,isozyme is still the most common means to measure genetic diversity of pines.Generally,there are high allozyme diversity within populations and low differentiation coefficient among populations,but differences exist between species in Pinus.The variations of chromosome among pines are very low and the karyotypes of pines are consentaneous,but the genomes of pines in cell nucleus are much larger than that of broadleaves.Diversity of pines are abundant at nucleus DNA level but are poor at plastid DNA level,such as ctDNA.There are many factors that will affect genetic diversity of pines,in which mating system and environment are two main factors.Finally,we reviewed the research on origin of Pinus and conservation strategy of genetic diversity,etc.  相似文献   

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