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1.
S. E. Schlarbaum R. J. Rose E. Small Lowell B. Johnson 《Plant Systematics and Evolution》1989,166(1-2):69-78
Studies were made on the chromosome complements and chloroplast genomes ofMedicago lupulina andM. secundiflora, which comprise sectionLupularia ofMedicago. Both types of analyses indicated more substantial differences between these species than suggested by external morphology.Medicago lupulina has a relatively asymmetrical karyotype in terms of centromeric position and relative length. The karyotype ofM. secundiflora is comparatively more asymmetrical in centromeric position and reduced in absolute size but exhibits greater symmetry in relative length. The restriction endonuclease fragmentation patterns of the chloropiast DNA of these two species (with Bam HI, Eco RI, Bgl II, and Xho I) show little similarity, with only 17% of the fragments matching in size. The lack of interspecific congruence among data of morphology, karyology and cpDNA inLupularia is contrary to consistency exhibited among these data inMedicago subsect.Intertextae. 相似文献
2.
Medicago intertexta andM. ciliaris have been controversially recognized as separate species. The only reliable diagnostic character, gland-tipped trichomes on the fruits inM. ciliaris, is controlled by presence of a single dominant allele, and such one-character taxonomies are debatable. Contributing to the difficulty,M. muricoleptis andM. granadensis, the other two species ofMedicago sectionSpirocarpos subsectionIntertextae, are sometimes confusingly similar toM. intertexta or to each other. Allozyme differences provided 95% verification of the suitability of the gland-tipped trichome character for separatingM. intertexta andM. ciliaris, thus corroborating their recognition as separate taxa. Several measures of allozyme variation indicated thatM. intertexta is more polymorphic than its sister species. Heterozygosity was also highest inM. intertexta, suggestive of a higher outcrossing rate, which is also consistent with larger floral size. Heterozygosity ofM. intertexta was concentrated in Sicily and nearby countries. Taxonomic difficulties in identifying SicilianM. intertexta are well known, and may be the result of interspecific hybridization and introgression.Medicago muricoleptis differed from the above two species in the frequency of several alleles, whileM. granadensis possessed numerous unique alleles consistent with its complete absence of genetic exchange with the other three substantially interfertile species. 相似文献
3.
The serological reaction of seed proteins provides evidence for a partly new systematic arrangement ofCytisus sect.Trianthocytisus and ofCytisus s.l. Proposed modifications agree with recent advances in morphological taxonomy. Sect.Trianthocytisus includes only two species,C. villosus andC. aeolicus. Its position is central within the genus, and this fact agrees with the proposed retypification ofCytisus (type species:C. villosus).C. emeriflorus, formerly included in the same section, constitutes the monospecific sect.Emeroides, which is intermediate towards the genusLembotropis. This is serologically isolated and includes onlyL. nigricans. It is confirmed thatC. sessilifolius should be removed from the genusCytisus as a monospecific genus:Cytisophyllum
Lang which is closely allied toHesperolaburnum and toPodocytisus, the most primitive genera ofGenisteae. 相似文献
4.
WithinEpilobium sect.Epilobium, a cytological analysis of 121 experimental hybrids, involving 40 species, indicates the presence of a widespread BB chromosome arrangement in Eurasia, Africa, and Australasia, as well as in North and South America less commonly. The AA chromosome arrangement, which differs from BB by one reciprocal translocation, occurs in North America, South America, and in at least three European species. The CC arrangement, which differs from AA by two reciprocal translocations, characterizes theAlpinae, a circumboreal group. Distinctive or only partly worked out chromosome arrangements occur in the EuropeanE. duriaei andE. nutans and in the North AmericanE. luteum, E. obcordatum, E. oregonense, andE. rigidum. With earlier results, the chromosome arrangements of some 65 of the estimated 185 species of the section have been established fully or partly. 相似文献
5.
L. sativa L. cultivars were compared morphologically with accessions ofL. saligna L.,L. serriola L., andL. virosa L. in order to define the infra- and interspecific variation. Multivariate analysis (principal component analysis) distinguished four groups corresponding with the four species. Infraspecific variation (e.g., colour, leaf shape) withinL. sativa is the largest, because breeding has caused a large variation in vegetative features; infraspecific variation withinL. serriola is also large. Three plants of one accession were placed betweenL. sativa andL. serriola because they showed morphological characteristics of both species. They are still classified asL. sativa. The morphological differences betweenL. sativa andL. serriola are too large to consider these two as one species. The descent of the cultivar groups and the four species is described. 相似文献
6.
A cytological analysis of 37 experimental interspecific hybrids withinEpilobium sect.Epilobium, involving 23 taxa, has indicated that the CC chromosome arrangement differs from BB by a single reciprocal translocation and was probably, like AA and DD, derived from it. Preliminary results suggest that the CC arrangement may characterize the AsianE. cephalostigma andE. platystigmatosum, which do not closely resemble the species in which it had earlier been detected. The BB arrangement is shown to occur in all North American species of theE. palustre group, includingE. oregonense. Direct evidence on chromosome arrangement is now available for some 85 of the approximately 185 species of the section, and may be inferred for at least 25 more. 相似文献
7.
A cytological analysis of 22 experimental interspecific hybrids withinEpilobium sect.Epilobium, involving 15 taxa, has indicated that the generalized western North AmericaE. obcordatum has the BB chromosome arrangement. This strengthens greatly our earlier contention that BB is the original chromosome arrangement in the section. The very distinctive northwestern North AmericanE. luteum, only species in the section with cream-colored petals, has the CC arrangement, like the members ofHaussknecht'sAlpinae. This chromosome arrangement apparently originated in the North Pacific region in plants that were of normal stature. The North AmericanE. leptocarpum, which closely resembles the Japanese endemicE. fauriei and, like it, forms gemmae in the axils of the upper leaves, also resembles it in having the CC chromosome arrangement. The AsianE. platystigmatosum has a novel chromosome arrangement derived from BB, which we here designate the EE arrangement. 相似文献
8.
Asplenium sect.Hymenasplenium is a well-defined group in Aspleniaceae, distinguished by several morphological and cytological characters. However, interspecific
relationships in the section were not clear. In this paper, we report the phylogenetic relationships of 9 Neotropical species
of sect.Hymenasplenium determined by chloroplast DNA restriction site variation analyses. From the obtained phylogenetic tree, two major clades:
one withA. obtusifolium, A. riparium, A. volubile andA. repandulum and another withA. delitescens, A. ortegae, A. purpurascens, A. laetum andA. hoffmannii were recognized.Asplenium delitescens was shown to have a polyphyletic origin. It was also shown that the epiphytic habit evolved only once in the New World species
of sect.Hymenasplenium. 相似文献
9.
Janina Przybylska Zdzisława Zimniak-Przybylska 《Plant Systematics and Evolution》1995,198(3-4):179-194
Electrophoretic analysis of seed albumins (PAGE) covered 173 accessions representing nine species ofVicia sect.Faba. The number of albumin bands recorded in particular species varied from three inV. eristaloides to 23 inV. faba; in total, 38 bands were distinguished in the investigated material. The examined species, exceptV. eristalioides, showed intraspecific variation with respect to the number and relative staining intensity of albumin bands; individual variation was especially marked inV. faba and inV. narbonensis. Hierarchical clustering of the investigated taxa was based onBhattacharyya distances calculated from the electrophoretic data. The taxa grouped in three main clusters.Vicia faba and the rather remotely relatedV. kalakhensis formed one cluster. The second cluster was composed ofV. narbonensis distantly related toV. hyaeniscyamus. The third cluster comprised three subgroups: 1.V. johannis, V. galilaea andV. serratifolia, 2.V. eristalioides, and 3.V. bithynica. The obtained results are discussed with reference to taxonomic relationships inVicia sect.Faba. 相似文献
10.
Åslög E. Dahl 《Plant Systematics and Evolution》1989,163(3-4):227-280
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
11.
Three taxa are distinguished in the sectionPhleum
Griseb. in Poland:P. nodosum (2n = 14),P. pratense (2n = 42), and the third one unformally named hereP. commutatum (2n = 14). It corresponds morphologically toP. commutatum
Gaud. reported as a tetraploid taxon (2n = 28) from other geographic regions. Giemsa C-banded karyotypes of these three taxa help clarify the taxonomic status ofP. commutatum and the origin of the hexaploidP. pratense. It is suggested that changes in the amount of telomeric heterochromatin played an important role in the evolution ofPhleum karyotypes. 相似文献
12.
Reexamination ofXanthoria persica, X. polycarpoides, X. lobulata gave evidence, that the thalli of these species are devoid of a lower cortex and rhizinae. Therefore, they do not fit the
definition of the genusXanthoria and are transferred toCaloplaca (under the new sectionXanthoriella) asCaloplaca persica, C. polycarpoides, andC. boulyi, respectively. — Details on development, anatomical structure, ecology and distribution are presented.
相似文献
13.
TheVicia sativa aggregate contains plants with different chromosome numbers karyotypes; they are still cross-compatible and have partially fertile F1-hybrids. There is also wide adaptive radiation and geographic distribution. The seed protein profiles ofV. sativa agg. are remarkably variable but no band or bands could be related to a specific karyotype, chromosome number or taxon, and variation within and between karyotypes are of the same magnitude. It is suggested that variation in the seed proteins ofV. sativa agg. might be an important agent for acquiring ecological flexibility, and that it is probably enhanced by interkaryotypic hybridization. 相似文献
14.
Twenty-six accessions of wildArachis species and domesticated peanuts,A. hypogaea, introduced from South America were analyzed for random amplified polymorphic DNA (RAPD). The objective of the study was to investigate inter- and intraspecific variation and affinities among species of sect.Arachis which have been proposed as possible progenitors for the domesticated peanut. Ten primers resolved 132 DNA bands which were useful for separating species and accessions. The most variation was observed among accessions ofA. cardenasii andA. glandulifera whereas the least amount of variation was observed inA. hypogaea andA. monticola. The two tetraploid species could not be separated by using RAPDs.Arachis duranensis was most closely related to the domesticated peanut and is believed to be the donor of the A genome. The data indicated thatA. batizocoi, a species previously hypothesized to contribute the B genome toA. hypogaea, was not involved in its evolution. The investigation showed that RAPDs can be used to analyze both inter- and intraspecific variation in peanut species. Southern hybridization of RAPD probes to blots containing RAPD of theArachis species provided information on genomic relationships and revealed the repetitive nature of the amplified DNA. 相似文献
15.
Classification of the genusAconitum (Ranunculaceae) has long been considered quite difficult because its species show high levels of morphological and ecological
variability. The molecular phylogeny of Asian aconites,Aconitum subgenusAconitum was, therefore, studied based on RFLP and sequences of the intergenic spacer between thetrnL (UAA) 3′ exon andtrnF (GAA), and of thetrnL intron, of the chloroplast DNA. UsingAconitum subgenusLycoctonum as an outgroup, we obtained a statistically reliable molecular tree composed of six clades branched radiatively at the very
base. There are three clades of Japanese aconites, a single clade of the species of Yunnan and Himalayas, and two clades of
Siberian plants. All the tetraploid taxa of Japan we studied did not show any difference based on the molecular characters
analyzed, though they have been classified into many taxa. Evolution and phytogeography of the Asian aconites as well as the
phylogeny are discussed. 相似文献
16.
Morphological and seed protein studies of selected species ofFestuca were performed to elucidate the relationships between species of sect.Ovinae and their affinity with other fescues.Festuca rubra andF. heterophylla (extravaginale group) had higher phenetic affinity with taxa of sect.Scariosae, Montanae andBovinae than with members of their own section. 5 species of the intravaginale group (F. ovina, F. capillata, F. valesiaca, F. sulcata, F. trachyphylla) were fairly uniform and well defined by protein and morphological data. This supports current systematic thinking and does not agree withHackel's (1882) classification of this group. 相似文献
17.
A survey is made of the occurrence, nature and frequency of satellited chromosomes in the agamospermous genusTaraxacum. Species belonging to the 10 sections thought to be most primitive in the genus lack satellited chromosomes. In most other sections, a characteristic satellited chromosome is seen with a large euchromatic region distal to the presumed nucleolar oraniser region (NOR). In sections of a precursor type, there is always one chromosome of this Taraxacum type per haploid genome. In sections thought to be of an advanced type the number of such satellited chromosomes is very unstable, sometimes even within the same tissue. In sectionHamata, two such satellited chromosomes are invariably found in triploids. This finding strongly supports the integrity of this section, suggests that the species of the section are monophyletic, and have evolved from a single ancestor subsequent to the occurrence of obligate agamospermy. In three sections of the genus, satellited chromosomes of the conventional type with a very small distal euchromatic region distal to the NOR are reported for the first time in the genus. 相似文献
18.
E. Martel V. Poncet F. Lamy S. Siljak-Yakovlev B. Lejeune A. Sarr 《Plant Systematics and Evolution》2004,249(3-4):139-149
19.
G. Venora S. Blangiforti M. Frediani F. Maggini M. T. Gelati M. Ruffini Castiglione R. Cremonini 《Protoplasma》2000,213(1-2):118-125
Summary Automated karyotype analyses, nuclear DNA contents, and sequences of rDNA internal transcribed spacers of the nine species inVicia sect.faba are reported. As karyomorphological parameters are used to evaluate the karyotype evolution, so the determination of the heterochromatin by Feulgen absorption at different thresholds of optical density provided further evidence on the chromatin organization withinVicia sect.faba. The comparison of sequences of rDNA spacers has enabled the definition of the phylogenetic relationships between the analyzed species. 相似文献
20.
R. P. S. Pundir R. B. Singh 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(3):307-313
Summary Somatic chromosomes of two cultivais of Cajanus cajan, eight species of Atylosia (A. albicans, A. cajanifolia, A. lineata, A. platycarpa, A. scarabaeoides, A. serica, A. trinervia and A. volubilis), and of Rhynchosia rothii were analysed. All species had 2n=22. Eight of the 10 species studied had two pairs of satchromosomes while A. scarabaeoides and A. sericea had only one sat-chromosome pair. Based on relative chromosome length (L%), arm ratio (pa-value) and presence or absence of secondary constriction, a karyotype formula for each species was formulated. Based on these parameters the chromosome pairs could also be assigned to groups ranging from 8 to 10 in different species. Except for the asymmetrical karyotype of A. albicans, the other species had rather moderately symmetrical karyotypes. 相似文献