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1.
A macromorphological study is made on taxa of the genusOrnithogalum subg.Heliocharmos in North Africa, Spain, and France. The results obtained are consistent with data from cytogenetics, reproductive biology and strategies of reproduction. They allow the retention of two species:O. algeriense andO. umbellatum. A biogeographical and phylogenetic interpretation of the subgenus is proposed for the western Mediterranean. Theoretical views on phenetics are discussed. 相似文献
2.
Macromorphological variation within theOrnithogalum umbellatum L. (Hyacinthaceae) complex in France was studied. The resulting data were treated by numerical taxonomy methods. Three morphs can be identified: one corresponding to diploid plants, another made up of triploids and a third which encompasses plants having ploidy level above 3x (4x, 5x, and 6x). A systematic interpretation of the complex is proposed wherein only one species,O. umbellatum, is retained. This species corresponds to a polyploid complex undergoing evolution. 相似文献
3.
Brita Stedje 《Plant Systematics and Evolution》1988,161(1-2):65-69
A new chromosome number (2n=4) forOrnithogalum tenuifolium
Delaroche is reported. The new chromosome race is postulated to have originated by a Robertsonian translocation from a Southern African chromosome race with six chromosomes, and represents thus the final step in a series of decreasing basic number of the species. 相似文献
4.
Principal component and canonical variate analyses were used to analyse the variation of 34 morphological characters measured in 98 accessions ofTulipa subg.Tulipa, formerly known as sect.Leiostemones. In addition 43 accessions were analysed cytogenetically by means of C-banding methods. Based on the encountered variation and on geographical distribution data 30 species in five sections were recognized, of which the synonymy is stated. Seven new series in two different sections have been designated. 相似文献
5.
The chromosomes of several cultivatedTulipa species belonging to the subg.Eriostemones were examined using conventional staining and C-banding techniques. Most of the species have lightly banded chromosomes with heterochromatin content varying from nil to about 15%. The banding patterns of several taxa are described and discussed in regard to species relationships. 相似文献
6.
Eugenia Zaharof 《Plant Systematics and Evolution》1986,154(1-2):41-61
The geographic variation inFritillaria graeca, an endemic of Greece, is explored, using multivariate techniques. Eleven morphological features were measured in each of 630 individual plants from 38 localities throughout the range of the species.Scheffe's a posteriori test revealed an almost continuous geographic variation and did not identify groups clearly. Discriminant analysis of the groups derived from an F significance test ofMahalanobis distance resulted in five major groups on the first two discriminant axes representing the subspeciesgraeca, ionica, guicciardii, thessala and its var.othria. A diagnostic key to theF. graeca subspecies is provided.This paper is a part of a doctoral dissertation dealing withFritillaria in Greece, to be submitted to the department of Biology of the Aristotelian University of Thessaloniki. 相似文献
7.
The chromosomes of several cultivatedTulipa species of subg.Leiostemones were examined in conventionally stained and C-banded preparations. The heterochromatin content varied from almost none to 45%. Several chromosome types were recognized with respect to chromosome morphology and heterochromatin distribution, and groups of species with common chromosome characteristics could be identified. These karyological relationships are discussed with respect to the groups formed on the basis of floral and bulb charateristics. 相似文献
8.
Scilla persica and 5 species of the so-calledS. hohenackeri group, namely,S. furseorum, S. puschkinioides, S. vvedenskyi, S. hohenackeri, andS. greilhuberi, have been investigated embryologically with special reference to embryo sac and endosperm development.Polygonum-type embryo sac development was stated inS. puschkinioides andS. greilhuberi. 8-nucleate, normally structured embryo sacs, which could not be specified further due to sparse availability of the material, were stated inS. furseorum, S. vvedenskyi, andS. hohenackeri. InS. persica the embryo sac develops according to the bisporicAllium-type. In most species endosperm development was stated to be nuclear, exceptS. hohenackeri, where the type could not be specified. Other traits of possible taxonomic significance are the number of layers in the outer integument, which is mostly 4, or 5–6 inS. furseorum, and the occurrence of polyploid versus haploid and early degenerating antipodal nuclei, the latter occurring only inS. persica andS. furseorum. These embryological characters may be useful for assessing taxonomic relationship of the present species with other allied groups withinScilla, in particular, theS. siberica alliance,S. messeniaca, and theS. bifolia alliance. TheAllium-type embryo sac, which occurs inS. persica, is also characteristic for theS. siberica alliance, and may be a common derived character. Lack of antipodal polyploidization, as characteristic forS. persica andS. furseorum, occurs also in theS. siberica alliance, and is perhaps another common derived trait indicating phylogenetic relationship. Nuclear endosperm development is more frequent in spring-flowering squills than helobial development, which has previously been stated inS. messeniaca, some species of theS. siberica alliance, and inS. litardierei. While helobial endosperm may be primitive forHyacinthaceae in general, it may, by reversal, also occur as a derived character, at least in some species of theS. siberica alliance. 相似文献
9.
Eugenia Zaharof 《Plant Systematics and Evolution》1988,161(1-2):23-34
40 population samples of 17 GreekFritillaria species were examined morphologically using 22 attributes carefully selected, with a high discriminating ability. Principal component analysis with a nearest neighbour directed network and cluster analysis were used to evaluate the phenetic similarities among the species. The evidence presented here suggests: (1) A close relationship betweenF. erhartii andF. obliqua and their possible origin fromF. bithynica. (2) A strong alliance betweenF. rixii, F. euboeica, F. carica, andF. drenovskii (groupF. sibthorpiana). (3) A link between theF. epirotica andF. graeca group and some affinities betweenF. pontica, F. gussichiae, andF. graeca. Finally it is proposed thatF. tuntasia be reduced to subspecific status asF. obliqua subsp.tuntasia.
This study forms a part of a doctoral dissertation thesis submitted to the Department of Biology of the University of Thessaloniki. 相似文献
10.
Yoshikane Iwatsubo Naohiro Naruhashi Heinrich E. Weber 《Plant Systematics and Evolution》1995,198(1-2):143-149
Chromosome numbers are presented for 32 collections of 29 European blackberry species (Rubus subg.Rubus) from Germany. One species is triploid (2n = 21), 27 species are tetraploid, (2n = 28), and one species is pentaploid (2n = 35). Chromosome numbers are reported for the first time ofR. adspersus, R. amisiensis, R. calvus, R. conothyrsoides, R. contractipes, R. demissus, R. elegantispinosus, R. ferocior, R. foliosus, R. hypomalacus, R. leucandrus, R. nemorosus, R. platyacanthus, R. praecox, R. rhombifolius, andR. rhytidophyllus. Chromosome numbers forR. dasyphyllus, R. gelertii, R. glandithyrsos, R. lamprocaulos, R. lindebergii, R. macrophyllus, R. montanus, R. muenteri, R. pedemontanus, R. polyanthemus, R. senticosus, R. silvaticus, andR. vigorosus are confirmed. 相似文献
11.
A classical morphological study ofHyacinthoides sect.Somera in the northwestern Iberian Peninsula revealed the new speciesH. paivae. It differs from the closely related speciesH. italica, H. hispanica, andH. mauritanica by vegetative and generative characters, such as leaf length, raceme shape, tepal length and width. It typically occurs in woodlands in the A Coruña province of NW Spain. 相似文献
12.
13.
棒凤仙亚属代表着凤仙花属最先分化出的一支,以多年生草本,多于5朵花的总状花序,侧生萼片4枚,3沟花粉,心皮四室且每室具1枚种子,果实棒锤状,种子椭圆形以及三沟花粉其极面观为三角形而区别于其它种类。该亚属主要分布于中国南部,少数种类辐射分布至华中和中南半岛地区。已有报道证实花粉的形态特征对凤仙花属植物的属下分类具有重要意义,但对棒凤仙亚属的种类少有涉及。为了进一步探讨该亚属花粉的形态特征及其分类学价值,该研究应用扫描电镜技术对国产棒凤仙亚属植物的14种以及凤仙花亚属的窄萼凤仙花的花粉进行了观察。结果表明:棒凤仙亚属的花粉以单粒存在,具3条萌发沟,辐射对称,极面观为三角形或三角状圆形,花粉粒外壁具均匀的网状纹饰,网脊平滑或具波状边缘,网眼中具不同密度的颗粒状突起。棒凤仙亚属的花粉形态与水角属的花粉形态相似,表现出了其原始性;其花粉形态特征与花部形态性状等相关性差,对该亚属的组级分类意义较小,但对于该亚属的种间界定具有重要意义;而其花粉的极面观形状、赤道面观形状以及网状纹饰等变异相对稳定,对于界定该亚属具有重要的分类学价值。 相似文献
14.
The paper presents the results of the study on seed morphology of four following Ornithogalum species: O. boucheanum Asch., O. nutans L., O. pyrenaicum L., and O. umbellatum L. Several macro-and micro-morphological characters were observed using stereoscope and scanning electron microscope. Differences
were found especially in micromorphological characters of the seed surface, the shape of raphe and micropylar pole. These
characters can be used as an additional taxonomic criterion at specific level for this genus. Only the seeds of O. boucheanum and O. nutans — two closely related and morphologically very similar species are practically undistinguished. 相似文献
15.
K. H. Rechinger 《Plant Systematics and Evolution》1990,172(1-4):151-192
Rumex sect.Axillares first described by the author in 1937 is known to be represented in N. America by 20 endemic species. From S. America only five species, all endemic, were previously known; this number is raised in the present revision to 15. Outside America there exist small groups of endemic species in S. Africa and in the islands of Hawaii as well as in Australia and scattered single species in C. Africa, on the remote Atlantic islands of Tristan de Cunha and Gough Island, and in eastern Asia.—In Europe the section is completely absent, except for three American species which occur as rare aliens. TheAxillares are not only morphologically well-characterized by their growth—no leaf rosettes, flowering period practically unlimited by formation of later flowering axillary shoots, flowers often monoecious—but also by their genetic structure expressed by a different behaviour in hybridization. Hybrids are frequent between species of sect.Rumex (syn.Simplices) and are easy to recognize by their sterility which results in a certain peculiarity in habit. In contrast, no spontaneous hybrids are known with certainty among species of sect.Axillares. Most artificial hybrids are fairly fertile. So far only three hybrids between species of the two sections have been known. Three more have been found by the author in Chile, all being highly sterile and showing the growth characteristics resulting from sterility as occur in hybrids between species of sect.Rumex.
Resumen Rumex secciónAxillares fue descrito por primera vez por el autor en 1937. Se conoce en América del Norte con 20 especies endémicas. De América del Sur se conocían sólo 5 especies, todas ellas endemicas; este número asciende a 15 en la presente revision. Fuera de las Américas se encuentran pequeños grupos de especies endémicas en Sudáfrica, en las Islas de Hawaii y en Australia; especies aisladas se encuentran en Africa Central, en las lejanas Islas Atlánticas de Tristan de Cunha y Gough Island y en Asia Oriental. La sección no tiene representantes en Europa, con excepción de tres especies americanas introducidas, poco frecuentes. La secciónAxillares se caracteriza bien, tanto morfológicamente por su forma de creciemiento—sin rosetas foliares, período floral prácticamente ilimitado por la formación de inflorescencias axilares parciales, flores a menudo monoicas—como por su estructura genética que se manifiesta en un comportamiento diferente de hibridación. Híbridos son frecuentes en las especies de la secciónRumex (syn.Simplices) y reconocibles por su esterilidad que se expresa en cierta particularidad del habito. Al contrario, no hay seguridad de híbridos espontáneos en la secciónAxillares. La mayor parte de los híbridos artificiales son totalmente fértiles. Hasta ahora se conocían solo tres híbridos entre las especies de ambas secciones. Otros tres han sido encontrados por el autor en Chile. Todos completamente estériles y con las características de hábito típicas resultantes la esterilidad, como ocurre en los híbridos de la secciónRumex.相似文献
16.
Emilia Andrzejewska-Golec Silke Ofterdinger-Daegel Ihsan Calis Lucjan Światek 《Plant Systematics and Evolution》1993,185(1-2):85-89
Within the genusPlantago, subg.Psyllium is characterized by the accumulation of the iridoids plantarenaloside and bartsioside. The latter compound was identified as constituent ofP. sempervirens for the first time. The structures of iridoids were determined by UV, IR,13C-NMR and1H-NMR. Both compounds are of chemotaxonomic value, as they are typical only of subg.Psyllium withinPlantago. The distribution of plantarenaloside within subg.Psyllium suggests the heterogeneity of this taxon. 相似文献
17.
Allozyme variation at eleven loci encoding seven enzyme systems were examined in 20 populations of diploid (genome AA, 2n = 16)Scilla scilloides in China. In comparison with the average species of seed plants studied, populations of this species display a high amount of genetic variation (A = 2.0, P = 58.6%, Ho = 0.172, and He = 0.185). Allozyme variation pattern revealed predominant outcrossing within populations and considerable differentiation (FST = 0.314) among populations as well as between the subtropic and temperate regions. The wide distribution, long existence and outcrossing are presumably the main factors responsible for the high genetic diversity within populations. But the gravity dispersal of seeds and pollination by small insects set limits to the increase of genetic variation within populations and promote differentiation between populations and regions. In addition, allozyme variation does not distinguishS. scilloides var.albo-viridis and suggests that subtropic populations may be considered as a genetic entity. 相似文献
18.
Gertrud Dahlgren 《Plant Systematics and Evolution》1991,177(3-4):193-211
This paper is the first report of an investigation on differentiation and evolutionary pattern inRanunculus subg.Batrachium mainly on the Aegean islands and treats the karyology in the subgenus. The following taxa and chromosome numbers are recorded.R. peltatus subsp.peltatus: 2n = 32, subsp.baudotii: 2n = 32, subsp.saniculifolius: 2n = 16, 32, and 40;R. peltatus s.l.: 2n = 32 and 48;R. penicillatus subsp.pseudofluitans: 2n = 16;R. rionii: 2n = 16;R. sphaerospermus: 2n = 16;R. trichophyllus: 2n = 32, 40, and 48;R. tripartitus: 2n = 48. The karyotypes show certain interspecific differences in chromosome size, in number of chromosome types according to centromere position and in occurrence and position of satellite chromosomes. r-Index and RCL have been calculated. 相似文献
19.
Although theCyclamen subg.Cyclamen spp. are morphologically variable, previous studies suggest a superficial cytological uniformity. New chromosome numbers and an indication of karyotypic instability are reported inC. hederifolium andC. africanum that reveal that the cytology of the subgenus is more complicated than previous accounts suggest. The possible significance of these phenomena is discussed. The diploid status ofC. purpurascens has been confirmed and a distinction between the three diploid karyotypes has been described. The cytological variation may help to explain the well documented morphological variation exhibited in these species. 相似文献
20.
The vegetative and reproductive morphology, culm and rhizome anatomy and seed surface micromorphology ofRhodocoma are described. It is shown that this variation is best contained by recognizing three new species in the genus. These new taxa are described, and the phylogeny of the genus is investigated by cladistic analysis. The environmental parameters and distributions of the species are related to the cladogram. This suggests that the species are at present ecologically separated, and indicates that the speciation may have been sympatric. This is the first support for the hypothesis that sympatric speciation may have been important in the speciose Cape flora. 相似文献