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1.
Six species and subspecies of theS. nemorensis group from the Carpathians are recognized here, based on morphometric analyses (cluster and discriminant analyses). A new speciesS. ucranicus Hodálová and a new hybridS. ×dominii Hodálová=S. germanicus WallrS. ucranicus Hodálová, occurring in the East Carpathians and the eastern part of the South Carpathians, are described. The vicarious nature ofS. hercynicus Herborg subsp.hercynicus, S. dacicus Hodálová etMarhold andS. ucranicus Hodálová in the Carpathians is documented. A key to theS. nemorensis group in the Carpathians as well as toS. nemorensis L. s. str. is presented.  相似文献   

2.
Introgressive hybridization of Senecio hercynicus and S. ovatus (Compositae, Senecioneae) was studied in a hybrid zone on the southern slopes of Mt Brocken (Harz Mountains, Germany). A total of 415 plants representing 10 stands along an altitudinal gradient were investigated using multivariate statistical analyses of morphological characters and molecular markers (random amplified polymorphic DNA[RAPD]). Both types of traits detected pure S. hercynicus stands on the summit plateau, pure S. ovatus stands at the lowest elevations, and hybrid swarms at intermediate elevations. While morphological and molecular patterns coincided, some individuals in hybrid stands combined morphological patterns typical of S. ovatus with RAPD patterns typical of S. hercynicus, and vice versa. In general, introgression was symmetrical within stands, though one stand combined S. ovatus characters with the glandular hair typical for S. hercynicus, and two stands combined a S. hercynicus typical RAPD genotype with morphological characters shifted towards S. ovatus. Because pure stands of S. hercynicus occurred only on the summit plateau of Mt Brocken, and markers typical for S. ovatus were detectable in stands up to 1040 m a.s.l., future fusion or assimilation of the rare form, S. hercynicus, by the more widespread S. ovatus appears possible at Mt Brocken.  相似文献   

3.
Quantitatively evaluated C-banded and conventional karyograms are presented for the related speciesScilla bifolia subsp.danubialis Speta,S. drunensis (Speta)Speta, andS. vindobonensis Speta. On the basis of banding patterns and karyotype structureS. bifolia subsp.danubialis (2n = 18, 2×) andS. drunensis (2n = 36, 4×) are quite similar, whileS. vindobonensis (2n = 18, 2×) is entirely different. There is a moderate degree of karyotypic variation withinS. bifolia subsp.danubialis andS. drunensis. However, inS. vindobonensis karyotypes and banding patterns are almost completely stable over a geographical range of about 500 km. The present results confirm the recent taxonomic separation ofS. vindobonensis fromS. bifolia, and suggest a considerable phylogenetic distance between these two diploid species. The results are discussed with reference to the morphological characters of the species and their geographical distribution.Evolution ofScilla and Related Genera, II.Dedicated to Univ.-Prof. Dr.Elisabeth Tschermak-Woess on the occasion of her 60th birthday.  相似文献   

4.
Mixed stands of Senecio ovatus subsp. ovatus and S. germanicus subsp. germanicus occur in the colline belt of central and eastern Europe. The latter species is adapted to more continental climate conditions and shows a later flowering time (August?CSeptember) than the widespread S. ovatus (July?CAugust) that grows in more oceanic climates. We have surveyed 253 plants from 15 populations north of Regensburg (south-eastern Germany) using 16 qualitative and quantitative morphological characters and molecular markers [amplified fragment length polymorphisms (AFLP)] to detect introgressive hybridisation between these two species. Both multivariate statistical analyses based on morphological characters and the Bayesian clustering based on AFLP fingerprint data show that in most populations under study the two species form distinct entities and do not hybridise with each other. However, in one population from the Upper Palatine Forest a high number of intermediate individuals were found. A more detailed genetic (AFLP) and phytochemical (pyrrolizidine alkaloid, PA) analysis based on 125 individuals from this hybrid swarm indicated that these intermediate individuals are backcrosses towards S. germanicus. It is shown that the two species differ considerably concerning the qualitative and quantitative PA patterns and that backcrossed individuals either show an additive PA pattern or a PA pattern similar to S. germanicus, while in quantitative respects all of these individuals are approaching S. germanicus. These findings are discussed in terms of differential selection regimes influencing the fitness of pure and hybrid plants in an area which is an eco-climatological optimum for the more oceanic S. ovatus but which forms a distributional edge for the more continental S. germanicus.  相似文献   

5.
Results obtained from crossing experiments betweenP. somniferum subsp.somniferum (2n = 22) and subsp.setigerum (2n = 44),P. glaucum (2n = 14) andP. gracile (2n = 14) and from the observation of meiotic chromosome pairing in the various hybrids obtained do not provide straightforward evidence for the hypothesis thatP. somniferum originated as a triploid hybrid between taxa similar toP. glaucum andP. gracile (Kadereit 1986a, b).—On the one hand, the pattern of crossability found reflects the closer similarity of subsp.somniferum toP. glaucum and of subsp.setigerum toP. gracile, which was interpreted as segregation of parental characters, and the high frequency of 2n = 28 chromosomes among F2-progeny from the hybrid subsp.somniferum × subsp.setigerum (2n = 33) might reveal n = 7 as the base number also ofP. somniferum. On the other hand, however, the general difficulty of obtaining hybrids, and the low incidence of bivalent formation in their meiosis, probably indicating a lack of chromosome homology between the different species, do not fit the above hypothesis.—These results are in marked contrast to the morphological similarity between the three species involved.  相似文献   

6.
InSedum rupestre L. a polyploid series (x = 16) occurs in which aneuploid chromosome numbers and odd levels of ploidy prevail. The most common and widely distributed cytotype,S. rupestre subsp.rupestre, is 2n = 112. Plants resemblingS. rupestre subsp.rupestre can be obtained by hybridizing the tetraploid cytotypes ofS. forsterianum Sm. (2n = 48) andS. rupestre subsp.erectum 't Hart (2n = 64). Comparison of these artificial hybrids with their parents and a large number of plants ofS. rupestre subsp.rupestre (2n = 112) from nature showed thatS. rupestre subsp.rupestre and the artificial hybrids are morphologically indistinguishable, and intermediate betweenS. forsterianum andS. rupestre subsp.erectum. MorphologicallyS. rupestre subsp.rupestre is closer to subsp.erectum than toS. forsterianum. Chloroplast DNA restriction patterns ofS. rupestre subsp.rupestre, however, resembleS. forsterianum more closely. The combined results of the hybridization experiments, the analysis of the cpDNA restriction patterns, and the morphological variation indicate the allopolyploid origin ofS. rupestre subsp.rupestre. Natural hybrids inSedum (Crassulaceae) 4.  相似文献   

7.
Morphological and cytological investigations were carried out inStachys beckeana Dörfler & Hayek andS. recta L. subsp.sarajevensis sensuHayek. These two taxa have the same morphological characteristics (shape and indumentum of leaves; morphology of sepals, petals and fruits) and both have 2n = 2x = 34 chromosomes. They cannot be considered as different taxa;S. beckeana Dörfler & Hayek is the valid name (synonyms:S. recta L. subsp.sarajevensis sensuHayek,S. hayekii Malý,S. recta L. subsp.hayekii Malý).
Erster Beitrag zur Neubearbeitung der Artengruppe derStachys recta L.  相似文献   

8.
Analyses of mitotic chromosome numbers and nuclear DNA content were performed for 39 populations of 17 perennial Cerastium taxa from south‐eastern Europe. The DNA content ranged from 2C = 2.43 to 8.78 pg, revealing four ploidy levels corresponding to 4x (2n = 36), 8x, 12x and 16x. High‐polyploid cytotypes with a greater range of ploidy (up to 2n = 144) occur mostly in the central mountainous parts of the Balkan Peninsula. The chromosome number was determined for the first time for C. dinaricum (2n = 36 + 1B), C. decalvans subsp. orbelicum (2n = 36), C. decalvans subsp. glutinosum (2n = 36), C. neoscardicum (2n = 144), C. malyi subsp. serpentini (2n = 144) and C. moesiacum s.s. (2n = 144). New chromosome counts were recorded for C. arvense subsp. strictum (2n = 108), C. banaticum subsp. kosaninii (2n = 36) and C. grandiflorum (2n = 36). For the first time, flow cytometry was used to estimate C values for six species (15 taxonomic entities). The intraspecific variation quotient of C values is high, ranging from 1.003 in C. malyi to 1.306 in C. decalvans subsp. decalvans. The variation in chromosome size among both tetra‐ and octoploid members of Cerastium is much more prominent than in most other angiosperm polyploid series. Significant genome downsizing after polyploidization was observed in some investigated taxa. Differences in ploidy levels and monoploid genome size values confirm the taxonomic status of C. decalvans subsp. glutinosum and C. decalvans subsp. leontopodium. The results obtained indicate a possible close relationship between C. banaticum and C. grandiflorum, but not C. arvense. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 182 , 205–224.  相似文献   

9.
Summary A gene library with DNA of Staphylococcus hyicus subsp. hyicus was established in S. carnosus by using the plasmid vector pCT20. Two clones of S. carnosus were isolated which were able to ferment d-ribose. The two hybrid plasmids (pRib 1) and (pRib 2) were isolated and characterized. They contained inserted DNA fragments of S. hyicus subsp. hyicus with sizes of 10.2 and 8.2 kb, respectively. d-Ribose uptake and enzyme activities were studied. All strains tested [S. hyicus subsp. hyicus, S. carnosus (wild type) and the two S. carnosus clones] possessed an inducible uptake system for d-ribose. S. hyicus subsp. hyicus possessed in addition enzyme activities of d-ribokinase and d-ribose-5-P isomerase. None of these enzyme activities could be detected in S. carnosus (wildtype). Only in the S. carnosus clones containing (pRib 1) or (pRib 2) could a d-ribokinase activity be demonstrated, indicating that the gene for d-ribokinase of S. hyicus subsp. hyicus was cloned in S. carnosus.Abbreviations bp base pairs - C-TLC cellulose-thin layer chromoatography - kb kilo base pairs - pRib 1 and 2 ribokinase activity conferring hybridplasmids - MBq megabequerel - wt wild type  相似文献   

10.
Silene thebana Orph. exBoiss. is transferred as a subspecies toS. fabaria (L.)Sm., resulting in the new combinationS. fabaria (L.)Sm. subsp.thebana (Orph. exBoiss.)Melzh. The chromosome count of 2n = 24 is recorded for the first time for this taxon.Dedicated to Prof. DrK. H. Rechinger on the occasion of his 80th birthday, 16th October 1986.  相似文献   

11.
Chromosome numbers are reported for 15 taxa ofHieracium sect.Alpina (Griseb.)Gremli from Central and eastern Europe (Austria, the Czech Republic, Poland, Romania, Slovakia, Ukraine). The mode of reproduction was also studied for some of the taxa. For the first time the chromosome counts of 5 taxa from theHieracium rohacsense group are given:H. rohacsense Kit. (the West Carpathians),H. ratezaticum (Nyár. etZahn)Mráz (the South Carpathians) and a still unnamed taxon of theH. rohacsense group from Mt. Pop Ivan (the East Carpathians) are tetraploid (2n=36);H. rauzense Murr (the Eastern Alps) andH. borsanum Mráz (the East Carpathians) are triploid (2n=27).H. krivanense (Woł. etZahn)Schljakov (the West Carpathians) is tetraploid,H. brevipiliferum Mráz (the South Carpathians) is triploid; these are the first karyological reports of both taxa belonging to theH. fritzei group. The tetraploid chromosome number was revealed for the first time in an unnamed taxon of theH. nigrescens group from the West Carpathians, and inH. nigrescens subsp.koprovanum Rech. f. etZahn. InH. alpinum L. s.str. triploid (2n=27) populations from the West Carpathians and diploid populations (2n=18) from the East Carpathians were confirmed. ForH. halleri Vill. (theH. alpinum group, the West Carpathians) andH. nigrescens Willd. (the West Sudeten), the numbers 2n=27 and 2n=36, respectively were found, which is in accordance with previous data. The triploid level (2n=27) forH. pinetophilum (theH. fritzei group) and the tetraploid level (2n=36) forH. stygium Uechtr. (theH. chlorocephalum group) both from the West Carpathians were confirmed. One new species, onenomen novum and one new combination at the level of species are published in this paper.  相似文献   

12.
Achiridae is an important family of the order Pleuronectiformes widely distributed in North, Central, and South America with freshwater and marine species. In the present study cytogenetic analyses comprising conventional and molecular techniques were carried out in seven species of this family. The following diploid numbers (2n) and fundamental numbers (FN) were obtained: Achirus declivis 2n = 34, FN = 52; Achirus lineatus 2n = 40, FN = 66; Catathyridium jenynsi 2n = 40 and FN = 50; Gymnachirus nudus 2n = 36 and FN = 50; Hypoclinemus mentalis 2n = 38 and FN = 54; Trinectes paulistanus 2n = 42 and FN = 52; and Trinectes sp. 2n = 38 and FN = 54. All species presented a single nucleolar organizer region (NOR) bearing chromosome pair and C-band positive segments mainly distributed at the pericentromeric position. The wide variation observed in chromosome number and FN suggests the occurrence of larger chromosome rearrangements in the family Achiridae if compared with other families of the same order.  相似文献   

13.
Patrik Mráz 《Biologia》2006,61(1):115-120
Second part of commented chromosome number and DNA ploidy level reports from Central Europe comprising the whole Carpatho-Pannonian region includes the data for following taxa: Tephroseris aurantiaca (2n = 96), T. capitata (2n = 64) and T. integrifolia (2n = 48) by J. Kochjarová from Poland and Slovakia (reports nos. 12–14); Urtica diocia and U. kioviensis (both 2n = 26) by M. Kolník & K. Goliašová from Slovakia (nos. 15–16); Viola hirta (2n = 20), V. odorata (2n = 20), V. reichenbachiana (2n = 20), V. riviniana (2n = 40, 2n ∼ 8x, based on x = 5), V. suavis (2n = 40) and V. × bavarica [V. reichenbachiana × v. riviniana] (2n ∼ 6x, based on x = 5) by P. Mereďa jun., I. Hodálová, P. Mártonfi & V. Kolarčík from Slovakia (nos. 17–22); Fallopia × bohemica [F. japonica × F. sachalinensis] (2n = 66), Thladiantha dubia (2n = 18) and Hieracium longifoliosum (2n = 36) by P. Mráz from Romania and Slovakia (nos. 23–25); Amsinckia calycina (2n = 34) by M. Perny & H. Šípošová from Slovakia (no. 26). For further details and arrangements of reports see the first part (Mráz, 2005).  相似文献   

14.
In addition to various types of natural hybrids betweenAster ageratoides subsp.ovatus andKalimeris incisa reported earlier, a new backcross type has been discovered. This new type, characterized by the chromosomes of 2n=27L+54S, was most probably produced through fertilization of a normally-reduced gamete of the F1 plant (2n=72=18L+54S) and an unreduced gamete of subsp.ovatus (2n=36=18L+18S).  相似文献   

15.
Hypecoum sect.Hypecoum comprises 8 species, one with 2 additional subspecies, in the Mediterranean area and the Middle East. Five of these are recognized for the first time, viz.Hypecoum procumbens L. subsp.fragrantissimum Å. E. Dahl,H. procumbens L. subsp.atropunctatum Å. E. Dahl,H. trullatum Å. E. Dahl,H. angustilobum Å. E. Dahl andH. torulosum Å. E. Dahl. H. dimidiatum Delile andH. pseudograndiflorum Petr., which have generally been included inH. imberbe Sm., are reestablished as distinct species. Morphology and variation patterns are described and discussed with special reference to mating systems. Self-incompatibility is dominating butH. procumbens subsp.procumbens andH. torulosum are self-compatible. The broad variation ranges of the former taxon in traits presumably related to mating system (petal, anther and stigma sizes as well as pollenovule ratios) indicate varying rates of outcrossing. SEM micrographs are given of petal and stigma surfaces and of pollen grains. Chromosome counts are presented for seven taxa. All are diploid with 2n = 16.  相似文献   

16.
Veronica lycica Lehm. is a distinct, diploid member of theVeronica cymbalaria group, endemic in Lycia (S.W. Anatolia). Closely related is the newV. stamatiadae M. Fischer etW. Greuter which is also diploid and seems to be restricted to the small Greek island Ro close to the South coast of Lycia. The chromosome numbers for both species are reported for the first time (2n = 18).
Untersuchungen über den PolyploidkomplexVeronica cymbalaria agg., II. — Der erste Beitrag dieser Serie:Fischer (1975).  相似文献   

17.
In a chemotaxonomic study of the genusSymphytum pyrrolizidine alkaloids and triterpenes were used as chemotaxonomical markers. A micro-extraction methods was developed for screening compounds of very small pieces of herbarium material. The occurrence of the pyrrolizidine alkaloids symphytine and (acetyl-)lycopsamine is very general forSymphytum taxa. Echimidine is present in someS. officinale L. plants and inS. tanaicense Steven. The triterpene isobauerenol is present inS. officinale, S. bohemicum Schmidt,S. tanaicense and inS. officinale var.lanceolatum Weinm. The chemotaxonomic hypothesis, proposed byGadella and collaborators, based on the presence of the triterpene isobauerenol inS. officinale and its absence inS. asperum Lepech. and the presence of the pyrrolizidine alkaloid echimidine inS. asperum and its absence inS. officinale, can no longer be applied absolutely to theS. officinale species complex. The pyrrolizidine alkaloid and triterpene pattern ofS. officinale (2n = 24) andS. bohemicum (2n = 24) is identical.S. bohemicum is morphologically, cytologically and phytochemically very similar toS. officinale. Furthermore, it readily crosses with the white flowered W. European diploids ofS. officinale. Therefore it seems likely that these two taxa are conspecific.S. tanaicense shows a pyrrolizidine alkaloid and triterpene pattern similar toS. officinale (2n = 40). Also on morphological and cytological grounds they are very similar. It seems highly probable thatS. tanaicense is conspecific withS. officinale (2n = 40) and represents an intraspecific variant only.S. officinale var.lanceolatum contained no pyrrolizidine alkaloids but did contain isobauerenol. This feature points to an origin fromS. officinale.  相似文献   

18.
FiveHypochoeris spp. from Sicily have been investigated:H. glabra L. (2n=10),H. radicata L. (2n=8),H. cretensis L. (2n=6),H. laevigata L. (2n=12),H. robertia Fiori (2n=8). Basic chromosome numbers are very variable, x = 3, 4, 5, 6. The karyotype of each species is presented. Geographical origin (S. America or Mediterranean region) of the genusHypochoeris and the taxonomic position ofH. robertia are discussed.  相似文献   

19.
Summary Based on meiotic chromosome behavior in intra- and interspecific hybrids, genome symbols were assigned to the following diploid (2n=40) Glycine species: G. canescens = AA; G. clandestina- Intermediate pod (Ip)=A 1 A 1; G. clandestina-Short pod (Sp)=BB; G. latifolia = B 1 B 1; G. tabacina = B 2 B 2; G. cyrtoloba = CC; and G. tomentella = DD. Genome symbol GG was reserved for the soybean, G. max. At metaphaseI, loose chromosome associations were observed in completely sterile interspecific hybrids whose parents differed in their genomes, suggesting some chromosome homologies among species. Although G. clandestina-Sp, G. latifolia and G. tabacina are morphologically distinct species, they differ only by a paracentric inversion. Similar observations were recorded for G. canescens and G. clandestina-Ip. Evidence is presented that demonstrates that G. tabacina (2n=80) and G. tomentella (2n=78, 80) are allotetraploid species complexes. Hybrid weakness, sterility, seedling lethality and seed inviability were found in intra- and interspecific hybrids.This research was supported in part by the Illinois Agricultural Experiment Station and the U.S. Department of Agriculture (Special grant 82-CRSR-2-2007). Travel grants to collect Glycine germplasm were received from the Rockefeller Foundation, the Illinois Soybean Program Operating Board, the National Science Foundation (INT76-14753) and the International Board for Plant Genetic Resources  相似文献   

20.
Hybridisation is an important evolutionary process. The investigation of hybridisation along elevational gradients, with their steep abiotic and biotic clines, provides insight into the adaptation and maintenance of species in adjacent habitats. The rare Senecio hercynicus and its spreading congener S. ovatus are vertically vicariant species that show hybridisation in their range overlaps. In the present study, we used AFLP fingerprinting of 689 individuals from 38 populations to analyse population structure and introgression patterns along four elevational transects (650–1350 m) in the Bavarian Forest National Park, Gemany. Subsequently, we searched for loci putatively under divergent selection that may maintain ‘pure’ species despite hybrid formation by identifying taxon-specific alleles. A maximum-likelihood based hybrid index shows that the overall genetic differentiation among all populations was very low with a vanishingly small number of pure parental individuals. Almost 75% of the investigated individuals were classified as backcrosses towards S. ovatus. The highest S. hercynicus ancestry was found in the uppermost populations of two transects. Further, we found seven taxon-specific alleles being under divergent selection that correlated with climatic variables and deviating from neutral introgression. According to our results, hybridisation of S. ovatus and S. hercynicus has reached an advanced state of genetic swamping and there seems to be no driving force that is strong enough to keep both species as different lineages. Rather, S. ovatus appears to benefit through putatively adaptive introgression.  相似文献   

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