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1.
Electrophoretic studies on seed storage proteins of various gymnosperm species showed that both salt soluble and insoluble protein fractions give taxonomic information. Among species of the genusPinus evident differences are found between the subgeneraHaploxylon (Strobus) andDiploxylon (Pinus). In sect.Strobus the two subsectt.Strobi andCembrae are readily distinguished fromP. bungeana (sect.Parrya) which appears to fall in an intermediate position between haploxyl and diploxyl pines. Among the species of subg.Diploxylon, mountain pines show very similar protein patterns in agreement with their recent speciation (Quaternary).  相似文献   

2.
3.
The perennial taxa ofCrucianella in Asia form a coherent group, apparently diploid (x = 11) and outbreeding throughout, and should be placed into sect.Roseae. This Irano-Turanian group has its centre of diversity in the mountain systems south of the Caspian Sea and reaches with outposts NE. and E. Anatolia, NE. Iraq, S. Iran and C. Asia. Four species and 13 subspecies (within the polymorphicC. gilanica) are recognized, described (partly as new), and illustrated (Figs. 1–6). Conspectus, keys and distribution maps (Figs. 7 and 8) as well as plesio- and apomorphic character states and data on size of areas are provided (Table 1). There is an obvious correlation between more plesiomorphic taxa with smaller areas in the distribution centre of the group, and more apomorphic taxa with larger areas towards its periphery (Fig. 9). These findings are linked to a working hypothesis on the evolution of the group.Dedicated to Prof. DrLothar Geitler on the occasion of his 90th birthday.  相似文献   

4.
André M. Amorim 《Brittonia》2002,54(4):217-232
Five-new taxa ofHeteropterys H. B. K. subsect.Aptychia Nied. are described, illustrated, and mapped:H. andina from Peru;H. minutiflora from Costa Rica; andH. bullata, H. capixaba, andH. oberdanii, from the Atlantic coastal forest of Brazil. The affinities and diagnostic characters of each species are discussed.  相似文献   

5.
Adonis sect.Consiligo is split into three subsections based on morphology, growth pattern, pollen and fruit morphology. For all species distribution maps are provided and discussed with regard to their ecology and climatic requirements. These data reveal additional characters that support the classification of the taxa. Most species of the section grow in continental Eurasiatic steppes and mountain steppe habitats. Only the species of subsect.Amurenses grow in Far Eastern temperate forests and prefer a more oceanic climate. The taxonomic position of these strongly divergent species is supported by the distributional and ecological data. The evolution ofAdonis sect.Consiligo occurred under strong climatic control. During evolution the taxa could only slightly widen their ecological amplitude and, thus, ecology remained rather stable except that of the subsect.Amurenses. Ecological and distributional data can be used to validate taxonomy and phylogeny and reveal additional informations.  相似文献   

6.
Thirty-seven natural populations of four closely related species ofPinus subsect.Sylvestres, P. mugo, P. funebris, P. pallasiana, andP. sylvestris, occurring in the former Soviet Union were investigated by starch-gel electrophoresis. In the populations assayed 127 allelic variants at 25 loci were revealed.Nei's distance coefficient (Dn) was used to estimate the level of genetic differentiation amongP. sylvestris races and among closely related species. A dendrogram constructed using Dn values shows that of the fiveP. sylvestris races analyzed only the geographically isolated var.hamata exhibited sufficient differences at theDia-2 locus (a mean Dn value relative to the other four races is 0.025) to recognize it as a distinct taxon. The remaining races, sylvestris, cretacea, lapponica, and sibirica, have a similar gene pool (Dn values are not greater than 0.010), and they should be regarded as a single taxon,P. sylvestris var.sylvestris. Interspecific comparisons revealed thatP. sylvestris andP. mugo have the closest genetic affinities to each other withNei's genetic distance of 0.108. The dendrogram demonstrates thatP. funebris is closer toP. sylvestris andP. mugo thanP. pallasiana. The available paleontologic data allowed us to conclude thatNei's (1975) time scale estimate for the time of divergence of the taxa was more accurate thanNei's (1971) time scale estimate.  相似文献   

7.
徐晗  李振宇  李俊生 《广西植物》2017,37(2):139-144
通过ITS序列对21种中国外来苋属植物进行系统进化关系研究。通过ITS序列种间、种内遗传距离分析,发现苋属种间变异为0~0.055 1,种内变异为0~0.009 2。使用TAXON DNA软件分析ITS序列种间、种内变异的分布图看出规律,结果表明苋属ITS序列的种间变异适中,种间变异明显大于种内变异。采用最大似然法(ML)构建的系统树将中国苋属分为5或6个进化支(根据自展支持率取值不同)。异株苋亚属长芒苋和苋亚属刺苋聚类在一起,西部苋和糙果苋单独成为一个进化支。苋亚属中苋组苋亚组反枝苋和绿穗苋亚组鲍氏苋有着更近的亲缘关系,苋组苋亚组尾穗苋和绿穗苋亚组绿穗苋、繁穗苋等亲缘关系更近。白苋亚属分为2或3个类群,根据自展支持率取值不同,合被苋可以和白苋、北美苋并为一支,也可以单独成为一支。综上所述,该文认为苋属经典分类体系中3亚属或2~3组的分类地位不成立,建议中国苋属采取5组2亚组或6组2亚组的分类体系。5组2亚组分别由长芒苋组、糙果苋组、苋组(苋亚组和绿穗苋亚组)、白苋组和凹头苋组组成。其中,合被苋也可从白苋组分出,单独构成1组,形成6组2亚组的分类体系。表明该序列对苋属大部分种类分类效果较好,对西部苋和糙果苋复合群,绿穗苋复合群以及白苋亚属的分类价值不高。  相似文献   

8.
Five new species ofAnthemis sect.Anthemis from the Flora Iranica region are described:A. gillettii (subsect.Anthemis) from NW. Iraq and adjacent Iran is allied toA. damascena.—A. kurdica (subsect.Anthemis) also grows in Iraqi Kurdistan.—A. hamrinensis (subsect.Rascheyana; akin toA. plebeia) is distributed in the Jabal Hamrin region at the extreme outer margin of the Zagros chains.—A. kandaharica (subsect.Anthemis) andA. freitagii (subsect.Rascheyana) are distributed in Afghanistan.
Anschrift des Herausgebers: Hofrat Univ.-Prof. Dr.Karl Heinz Rechinger, Beckgasse 22, A-1130 Wien, Österreich.  相似文献   

9.
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   

10.
Surveys conducted from 1973 to 1984 showed thatAnaphes diana Girault was the predominant parasitoid ofSitona spp. eggs throughout the Mediterranean range of Spain, France, Italy, Greece, Bulgaria, Romania, Turkey and Syria. In each of these countries, the mean percentage parasitism of eggs fluctuated between 1.9 and 23.9%. The impact of the mymarid on its host increased considerably from autumn to spring. Two biotypes ofA. diana, one reproducing bisexually, the other being strictly thelytokous, occur sympatrically in the Mediterranean region. The origin of various consignments ofSitona eggs parasitized byA. diana shipped to Australia for field release of the mymarid is recorded. Egg parasitoids were found in the Damascus area (Syria) that may be adapted to and effective under the hot and dry climatic conditions of South Australia.  相似文献   

11.
In eight natural European populations of four closely related taxa of pines (Pinus sylvestris, P. mugo, P. uncinata, andP. uliginosa) starch-gel electrophoreses revealed altogether 58 alleles at 15 loci from nine enzyme systems. With Nei's genetic distance (D) the largest mean genetic distance (D = 0.171) was found betweenP. sylvestris andP. mugo, a distance corresponding to that between other closely related pine species. Mean genetic distances between the other taxa were less than half that value and characteristic for subspecies or varieties rather than for species. On the basis of our results we suggest that both,P. uliginosa andP. uncinata, could be the result of the ancient hybridization betweenP. sylvestris andP. mugo.  相似文献   

12.
Cortinarius is one of the most species-rich genera of mushroom-forming fungi. Based on phylogenetic and morphological evidence, Cortinarius, sect. Riederi, is introduced at sectional level (= subsect. Riederi sensu Brandrud & Melot). The taxonomy, phylogeny, ecology and distribution of not only mainly European but also including some North American taxa of this section are treated, which includes nine species and two varieties. Of these, three taxa are described as new (C. burlinghamiae, C. pallidoriederi and C. argenteolilacinus var. dovrensis). The sect. Riederi species possess morphological features similar to Phlegmacium group(s) and forms a phylogenetically isolated lineage, with no supported affinity to other phlegmacioid groups. Three taxa are known from both Europe and North America, two species are known only from North America and five only from Europe. Altogether, eight of the ten taxa are associated with conifers or northern (boreal-subalpine) deciduous trees (Betula spp.). Only two species occur in more temperate forests (Fagus forests), and no species have so far been found in thermophilous Quercus forests  相似文献   

13.
The karyotypes of three taxa from thePhleum alpinum group of sect.Phleum (P. alpinum subsp.rhaeticum, 2n = 14,P. commutatum, 2n = 28, and informally namedP. commutatum, 2n = 14) were investigated by Giemsa C-banding. The overall similarity of diploid genomes suggests thatP. alpinum subsp.rhaeticum andP. commutatum are closely related — their karyotypes vary only with respect to their average amounts of telomeric heterochromatin. TheP. commutatum genome contains less telomeric heterochromatin than the genome ofP. alpinum subsp.rhaeticum, but in theP. alpinum group as a whole almost fluent transition between low (1.5%) and high (25.5%) amounts of telomeric heterochromatin was observed among populations. In the karyotype of tetraploidP. commutatum, seven distinguishable chromosome types were observed. Each of them is represented at somatic metaphase by four chromosomes. C-band structure of karyotype and average amount of telomeric heterochromatin suggest that this taxon has originated from hybridization between two related diploid forms of theP. commutatum — P. alpinum complex.  相似文献   

14.
The genusPinus includes over 90 species with approximately 24 species native to Asia. We have analyzed the chloroplast (cp) DNA variation of 18Pinus species, including 15 Asian, two Eurasian, and one European species using seven restriction enzymes and ten non-overlapping probes and inferred their phylogenetic relationships. Results of phenetic and cladistic approaches to phylogeny reconstruction were largely in agreement, suggesting two major lineages within the genus and confirmed the ancient character of haploxylon and diploxylon subgenera. Species from sectionParrya appear to have diverged earliest from the hypothesized phylogenetic centre for the haploxylon pines, withP. bungeana andP. gerardiana forming two basal, monotypic lineages. The range of estimated pairwise nucleotide substitutions per site ( ) was higher among haploxylon pines than among diploxylon species. CpDNA divergence was found to be low within the sectionSylvestres, relative to the divergence among haploxylon species, suggesting that the radiation of this group of taxa from its common ancestor occurred after the diversification of other groups. The low cpDNA divergence in this subsection corroborated earlier evidence for its phylogenetic cohesiveness and existence as a monophyletic group.  相似文献   

15.
Astragalus (sect.Argophylli subsect.Pseudargophylli)holmgreniorum, from the Virgin valley along the Utah-Arizona border, and A. (sect.Reventi-Arrecti subsect. Orcuttiani)ackermanii, from S Nevada, are described, figured and discussed.  相似文献   

16.
17.
Campanula schimaniana is a new species of sect.Campanula subsect.Rupestres, distributed in the westernmost mountains affected by monsoon.
Additamentum ad Floram Iranicam III. — Additamentum praecurrens in Candollea34, 279–305.  相似文献   

18.
The usefulness of features of leaf hairs in distinguishing subgenera and sections is well documented in bothRhododendron andSolanum. In this analysis of the taxa ofSolanum sect.Basarthrum (23 species), and of a sample of closely related taxa from sect.Petota (22 species), it is shown that such features serve to delineate subsectional groups such as series and some species as well. SectionBasarthrum has an unexpected diversity of hair types. Although this group has been characterized by 2-celled bayonet hairs, more than one half of the taxa in the section bear multicellular finger hairs, and 3 species also possess branched hairs. Thus, major rearrangements of the species previously assigned to sect.Basarthrum are indicated or supported by pubescence features. The taxa studied from seriesEtuberosa andJuglandifolia (both of sect.Petota) show hair types that a) are relatively primitive for the section, and b) show linkage between sects.Petota andBasarthrum.  相似文献   

19.
Vochysia palmirana is described and illustrated as a new species. It is a member of sect.Vochysiella subsect.Decorticantes. It grows in sandy Cerrados of the Central Brazilian Plateau and is similar toV. sessilifolia. A key to the species ofVochysia sect.Vochysiella subsect.Decorticantes is provided.  相似文献   

20.
Chromosome counts are reported for several E. Alpine taxa ofEuphrasia sect.Euphrasia. First records of diploidy for small-flowered taxa are 2n = 22 forE. inopinata andE. sinuata, related toE. minima (4 x). Aberrant E. AlpineE. hirtella is 2 x, just as the typical W. Alpine populations of this species. Tetraploidy, 2n = 44, has been found inE. pumila, close toE. stricta (also 4 x). The limitation of ploidy levels within sect.Euphrasia to 2 x and 4 x on the chromosome base number x = 11 is confirmed.
  相似文献   

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