ÉTUDES SUR LE GENRE SOLIDAGO L. : II. LA MISE EN ÉVIDENCE DE LA POLYPLOÏDIE ENDOTAXONIQUE CHEZ S. PURSHII PORTER ET LES TAXA SIMILAIRES

1958 ◽  
Vol 36 (5) ◽  
pp. 663-670 ◽  
Author(s):  
Jean R. Beaudry ◽  
Alexis Zinger ◽  
Jacques Saint-Pierre
Keyword(s):  
Chromosome Number ◽  
Geographical Distribution ◽  
Chromosome Numbers ◽  
Guard Cells ◽  
Morphological Characters ◽  
The Other ◽  
Herbarium Specimens ◽  
Positive Correlation ◽  
Rapid Technique

In Solidago Purshii Porter, there are two cytodemes, one diploid (2n = 18) and the other tetraploid (2n = 36), which can be distinguished on the basis of the length of the guard cells of their leaf stomata. The diploid plants possess guard cells which are smaller than those of the tetraploid. These two entities of S. Purshii thus belong to the groups of cytodemes in which there exists a positive correlation between the chromosome numbers and the dimensions of certain quantitative morphological characters, such as the length of the guard cells.In groups in which the variation curves of the characters of the different cytodemes overlap little or not, the geographical distribution of the different cytodemes of the complex may be studied much more easily, rapidly, and comprehensively by measuring the length of the guard cells of herbarium specimens than by making chromosome number determinations. The data presented indicate that when sampling is made under the conditions described in this paper, determinations of the length of two guard cells of stomata of one mid-leaf per individual, made on two individuals per colony, is satisfactory for that purpose, on the average. However, it is recommended, as a safeguard, to increase these figures by a few units, and to make always a few direct chromosome number determinations to check the accuracy of this rapid technique. These direct determinations may also be necessary to know the chromosome numbers of certain extreme individuals of the different cytodemes which have guard cells that differ little in length.

STUDIES ON SOLIDAGO L.: IV. THE CHROMOSOME NUMBERS OF CERTAIN TAXA OF THE GENUS SOLIDAGO

1959 ◽  
Vol 37 (2) ◽  
pp. 209-228 ◽  
Author(s):  
Jean R. Beaudry ◽  
Denise L. Chabot
Keyword(s):  
North America ◽  
Chromosome Number ◽  
Geographical Distribution ◽  
Chromosome Numbers ◽  
Morphological Characters ◽  
Basic Number ◽  
Western North America

The authors report the chromosome numbers of 25 taxa of the genus Solidago which had not yet been studied from this standpoint, and review the literature. The chromosome numbers of 42 taxa have now been published. The basic number of the genus is nine. Thirty-three taxa are diploid (2n = 18), five are tetraploid (2n = 36), three are aggregate taxa containing both diploid and tetraploid cytodemes, and one is hexaploid (2n = 54). Polyploidy has thus contributed to the evolution of the genus Solidago but it seems that most of the species have differentiated gradually. S. decemflora DC. of western North America differs from S. nemoralis Ait. of the same continent by morphological characters, its geographical distribution, and its chromosome number, the first taxon being tetraploid and the second diploid; the two are thus good species and not only varieties of the same species. The S. rigida of authors is an aggregate made up of two entities which are distinguished not only by their morphology and geographical distribution but also by their chromosome numbers; the eastern one (S. rigida L.) is tetraploid, whereas the western one (S. parvirigida Beaudry) is diploid. The bog and marsh goldenrods, S. Purshii and S. uliginosa, also possess different chromosome numbers, the first being diploid and the second tetraploid.

Evidence against the existence of varieties in Arctagrostis latifolia ssp. arundinacea (Poaceae)

1994 ◽  
Vol 72 (7) ◽  
pp. 1039-1050 ◽  
Author(s):  
S. G. Aiken ◽  
L. P. Lefkovitch ◽  
Susan E. Gardiner ◽  
W. W. Mitchell
Keyword(s):  
Chromosome Number ◽  
Key Words ◽  
Guard Cell ◽  
Morphological Study ◽  
Seed Protein ◽  
Morphological Diversity ◽  
Guard Cells ◽  
Herbarium Specimens ◽  
Banding Patterns ◽  
Sds Page

The morphological diversity of North American specimens of Arctagrostis latifolia ssp. arundinacea (Trin.) Tzvelev was evaluated for possible varieties within the subspecies by considering (i) descriptions of three previously recognized taxa included in the subspecies, (ii) measurements of spikelet characters of the types of five taxa, (iii) Macoun's illustrations of spikelet diversity, (iv) a morphological study of 130 herbarium specimens, and (v) a transplant garden study. Characters thought to be uninfluenced by environment were examined. These included (i) the seed protein banding patterns revealed by SDS–PAGE, (ii) the guard cell sizes from plants of known chromosome number, and (iii) a study of anther lengths and pollen diameters. The data do not support the recognition of varieties. Key words: SDS–PAGE, transplant garden, pollen, chromosome number, guard cells, Arctagrostis, Poaceae, taxonomy.

The genus Rubus in South Africa. I. Chromosome numbers and geographical distribution of species

Bothalia ◽  
1984 ◽  
Vol 15 (3/4) ◽  
pp. 591-596 ◽  
Author(s):  
J. J. Spies ◽  
H. Du Du Plessis
Keyword(s):  
South Africa ◽  
South African ◽  
Geographical Distribution ◽  
Chromosome Numbers ◽  
The Other ◽  
The South ◽  
African Species ◽  
Rubus Species ◽  
First Time

The geographical distribution of 14 of the Rubus species in South Africa is presented. Chromosome numbers of nine of the species were determined: six for the first time, one is confirmed and additional polyploid levels are described for the other two species. It is demonstrated that the South African species of the subgenus Idaeobatus contain less diploid specimens and more polyploid specimens than their extra-African counterparts. This phenomenon could be attributed to hybridization between the subgenera Eubatus and  Idaeobatus.

Taxonomic revision of Carex chungii (Cyperaceae; sect. Mitratae) and allied species

Phytotaxa ◽  
2017 ◽  
Vol 317 (1) ◽  
pp. 29
Author(s):  
XIAO-FENG JIN
Keyword(s):  
Principal Component Analysis ◽  
Entire Range ◽  
Principal Component ◽  
Taxonomic Revision ◽  
Morphological Characters ◽  
Literature Survey ◽  
The Other ◽  
Morphological Data ◽  
Herbarium Specimens ◽  
Specific Rank

In this paper, Carex chungii and other five names at species rank, plus one variety and one form, all from of C. sect. Mitratae, were revised. They constitute a group of morphologically very similar taxa, difficult to tell apart. Our study was based on literature survey, fieldwork, herbarium specimens, statistical analysis of morphological characters and SEM observations of achenes and perigynia. Analysis of morphological data of 94 individuals from eleven populations using principal component analysis (PCA) revealed five clusters, which we consequently considered to correspond to five species. The achenes of Carex genkaiensis were strikingly different from all the other species regarding achene apex contracted into a 0.2–0.5 mm long neck-like appendage (vs. into a discoid-annulate style-base), as well as its perigynium indumentum (pubescent vs. sparsely pubescent). Carex anhuiensis, C. xuanchengensis and C. truncatirostris f. erostris are all synonymized to C. truncatirostris. The previously recognized Carex kamagariensis from Japan is synonymized to C. chungii. Carex chungii var. rigida is recognized as specific rank and the new name C. nanpingensis is proposed. Our study is the first effort to address the taxonomy of this complicate group as a whole in its entire range.

scholarly journals A New Species of the Mexican Tillandsia erubescens Group (Bromeliaceae)

Phytotaxa ◽  
2016 ◽  
Vol 260 (1) ◽  
pp. 57 ◽  
Author(s):  
CAROLINA GRANADOS MENDOZA ◽  
GERARDO A. SALAZAR ◽  
MARÍA FLORES-CRUZ
Keyword(s):  
New Species ◽  
Geographical Distribution ◽  
Habitat Preferences ◽  
Taxonomic Revision ◽  
Extensive Study ◽  
The Other ◽  
Oak Forests ◽  
Herbarium Specimens ◽  
High Mountains ◽  
A New Species

The Tillandsia erubescens group (Bromeliaceae) encompasses seven currently recognized species with reduced, pendulous inflorescences and endemic to pine-oak forests in the high mountains of Mexico. During the course of a taxonomic revision based on extensive study of herbarium specimens and detailed observations in the field, a new species of this group was discovered, which is described and illustrated here as T. tecolometl. The new entity belongs to a subgroup of species with purple corollas that also includes T. andrieuxii, T. macdougallii, T. oaxacana and T. pseudooaxacana. We present detailed morphological comparisons of the new species to the other species in the group with purple corollas, complemented with information on their habitat preferences, geographical distribution and phenology. An identification key to all the species with purple corollas belonging to the Tillandsia erubescens group is provided.

scholarly journals A checklist of chromosome numbers and a review of karyotype variation in Odonata of the world

2020 ◽  
Vol 14 (4) ◽  
pp. 501-540
Author(s):  
Valentina G. Kuznetsova ◽  
Natalia V. Golub
Keyword(s):  
Chromosome Number ◽  
Chromosome Numbers ◽  
Sex Chromosome ◽  
The Other ◽  
Local Modes ◽  
Insect Order ◽  
Extant Species ◽  
The World ◽  
Phylogenetic Lineages ◽  
Sex Determination Mechanisms

The ancient insect order Odonata is divided into three suborders: Anisoptera and Zygoptera with approximately 3000 species worldwide each, and Anisozygoptera with only four extant species in the relict family Epiophlebiidae. An updated list of Odonata species studied regarding chromosome number, sex chromosome mechanism and the occurrence of m-chromosomes (= microchromosomes) is given. Karyotypes of 607 species (198 genera, 23 families), covering approximately 10% of described species, are reported: 423 species (125 genera, 8 families) of the Anisoptera, 184 species (72 genera, 14 families) of the Zygoptera, and one species of the Anisozygoptera. Among the Odonata, sex determination mechanisms in males can be of X(0), XY and X1X2Y types, and diploid chromosome numbers can vary from 6 to 41, with a clear mode at 2n = 25(60%) and two more local modes at 2n = 27(21%) and 2n = 23(13%). The karyotype 2n = 25(24A + X) is found in each of the three suborders and is the most typical (modal) in many families, including the best-covered Libellulidae, Corduliidae (Anisoptera), Lestidae, Calopterygidae, and Platycnemididae (Zygoptera). This chromosome set is considered ancestral for the Odonata in general. Chromosome rearrangements, among which fusions and fissions most likely predominated, led to independent origins of similar karyotypes within different phylogenetic lineages of the order. The karyotype 2n = 27(26A + X) prevails in Aeshnidae and Coenagrionidae, whereas the karyotype 2n = 23(22A + X) is modal in Gomphidae and Chlorocyphidae, in both pairs of families one being from the Anisoptera while the other from the Zygoptera.

scholarly journals A checklist of chromosome numbers and a review of karyotype variation in Odonata of the world

2020 ◽  
Vol 14 (4) ◽  
pp. 501-540
Author(s):  
Valentina G. Kuznetsova ◽  
Natalia V. Golub
Keyword(s):  
Chromosome Number ◽  
Chromosome Numbers ◽  
Sex Chromosome ◽  
The Other ◽  
Local Modes ◽  
Insect Order ◽  
Extant Species ◽  
The World ◽  
Phylogenetic Lineages ◽  
Sex Determination Mechanisms

The ancient insect order Odonata is divided into three suborders: Anisoptera and Zygoptera with approximately 3000 species worldwide each, and Anisozygoptera with only four extant species in the relict family Epiophlebiidae. An updated list of Odonata species studied regarding chromosome number, sex chromosome mechanism and the occurrence of m-chromosomes (= microchromosomes) is given. Karyotypes of 607 species (198 genera, 23 families), covering approximately 10% of described species, are reported: 423 species (125 genera, 8 families) of the Anisoptera, 184 species (72 genera, 14 families) of the Zygoptera, and one species of the Anisozygoptera. Among the Odonata, sex determination mechanisms in males can be of X(0), XY and X1X2Y types, and diploid chromosome numbers can vary from 6 to 41, with a clear mode at 2n = 25(60%) and two more local modes at 2n = 27(21%) and 2n = 23(13%). The karyotype 2n = 25(24A + X) is found in each of the three suborders and is the most typical (modal) in many families, including the best-covered Libellulidae, Corduliidae (Anisoptera), Lestidae, Calopterygidae, and Platycnemididae (Zygoptera). This chromosome set is considered ancestral for the Odonata in general. Chromosome rearrangements, among which fusions and fissions most likely predominated, led to independent origins of similar karyotypes within different phylogenetic lineages of the order. The karyotype 2n = 27(26A + X) prevails in Aeshnidae and Coenagrionidae, whereas the karyotype 2n = 23(22A + X) is modal in Gomphidae and Chlorocyphidae, in both pairs of families one being from the Anisoptera while the other from the Zygoptera.

Confirmation of Calamagrostis salina in China, previously misidentified as C. macilenta, and notes about C. kokonorica and C. macilenta (Poaceae, Agrostidinae)

Phytotaxa ◽  
2016 ◽  
Vol 268 (4) ◽  
pp. 251 ◽  
Author(s):  
BEATA PASZKO ◽  
WEN-LI CHEN ◽  
BING LIU
Keyword(s):  
Geographical Distribution ◽  
Related Species ◽  
Northern China ◽  
Morphological Characters ◽  
Herbarium Specimens ◽  
Anther Length ◽  
First Time ◽  
Diagnostic Importance

New data on the taxonomy and distribution of three Calamagrostis (including Euroasian Deyeuxia) species (C. kokonorica, C. macilenta, and C. salina) in northwestern and northern China are discussed. Studies were undertaken on the morphological characters to establish relatedness or not of species, and identify characters of diagnostic importance. Chinese herbarium specimens of C. salina previously have been misidentified as Deyeuxia macilenta (= C. macilenta). All available for study Chinese specimens referred to this species should be identified as C. salina. Calamagrostis salina significantly differs from C. kokonorica and C. macilenta by the palea length, relative lengths of palea and lemma, and anther length. Calamagrostis salina is confirmed for Xinjiang, and reported for the first time from Gansu, Nei Mongol and Qinghai. Calamagrostis kokonorica is confirmed for Gansu and Qinghai. The presence of C. macilenta in China is in need of further confirmation. A revised key for C. salina and related species are provided. The descriptions of all taxa are accompanied by information on their geographical distribution in China and adjacent countries.

Observations on Canadian birches, Betula cordifolia, B. neoalaskana, B. populifolia, B. papyrifera, and B. × caerulea

1975 ◽  
Vol 53 (15) ◽  
pp. 1478-1490 ◽  
Author(s):  
W. F. Grant ◽  
B. K. Thompson
Keyword(s):  
New Brunswick ◽  
Growth Rates ◽  
Chromosome Numbers ◽  
Somatic Chromosome ◽  
Morphological Characters ◽  
The Other ◽  
Canonical Analysis ◽  
Early Age ◽  
Somatic Chromosome Numbers

Ten morphological characters have been examined from 455 collections of B. papyrifera Marsh., 95 collections of B. cordifolia Regel, 56 collections of B. populifolia Marsh., 64 collections of B. neoalaskana Sarg., and 70 collections of B. × caerulea Blanch. taken from their ranges within Canada. The somatic chromosome numbers were found to be 70, 84, and more rarely 56 (possibly hybrids) for B. papyrifera, 28 and more rarely 42 and 56 for B. cordifolia, and 28 for B. populifolia, B. neoalaskana, and B. × caerulea. Observations on juvenile characters and growth rates indicated that it is possible to distinguish these taxa at an early age. Comparison of the characters on an interprovincial basis within species revealed no significant differences in B. populifolia (P < .05). However, significant differences were observed in one or more characters from the other species. No significant differences were found between species when B. papyrifera was either sympatric or allopatric with B. cordifolia and B. populifolia; when B. cordifolia was sympatric but B. populifolia was not; and when B. populifolia was sympatric but B. cordifolia was not. A canonical analysis of the New Brunswick data incorporating the 10 characters indicated clear distinctions among B. papyrifera, B. cordifolia, and B. populifolia and provided further evidence that B. × caerulea is a hybrid of B. populifolia and B. cordifolia. Considerable introgression of B. caerulea with B. populifolia was noted in these data.

Dupontia (Poaceae) in North America

2003 ◽  
Vol 81 (8) ◽  
pp. 769-779 ◽  
Author(s):  
A K Brysting ◽  
S G Aiken ◽  
L P Lefkovitch ◽  
R L Boles
Keyword(s):  
Chromosome Numbers ◽  
Morphological Characteristics ◽  
Field Work ◽  
Distinct Species ◽  
Plant Size ◽  
Morphological Characters ◽  
Herbarium Specimens ◽  
Ploidy Levels ◽  
Random Variability ◽  
Conditional Clustering

Challenged by work on the Panarctic Flora project and apparent discrepancies in recent taxonomic treatments, the genus Dupontia was studied from herbarium specimens, including types and chromosome vouchers, and by numerical taxonomy, mapping the distribution of morphological characteristics, consideration of chromosome numbers, and field work in the Canadian Arctic. Our results using these techniques show random variability in many characters and differences in plant size that appear to be partly habitat related. The treatment of the genus has varied from the recognition of one variable species to three or more distinct species. Morphological characters, used in the literature to divide the genus Dupontia into more than one taxon, cannot be reliably applied to distinguish most North American plants. Continuous morphological variation in combination with high and variable ploidy levels, effective vegetative growth, and rare sexual reproduction suggests the use of a broad species concept. Until further evidence is available, our results support treating the genus as monotypic.Key words: Poaceae, Dupontia, morphology, chromosome numbers, conditional clustering, contingency tables.

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