The Antennaria frieseana (Asteraceae: Inuleae) polyploid complex: morphological variation in sexual and agamospermous taxa

1994 ◽  
Vol 72 (7) ◽  
pp. 1018-1026 ◽  
Author(s):  
Jerry G. Chmielewski
Keyword(s):  
Chromosome Number ◽  
Key Words ◽  
Reproductive Biology ◽  
Morphological Variation ◽  
Polyploid Complex ◽  
Corolla Length

The Antennaria frieseana (Trautv.) Ekman polyploid complex has been evaluated on numerous occasions without concensus to either the taxa that should be included or their proper ranks. The purpose of this phenetic study was to present a taxonomy for the polyploid complex that is not only independent of a knowledge of chromosome number and reproductive biology but that concurrently reflects morphological variation associated with each. The rank of subspecies (A. frieseana ssp. frieseana and A. frieseana ssp. alaskana (Malte) Hultén) was accepted as the most appropriate level of circumscription that satisfied the purpose of the phenetic study and was supported by the analysis. These subspecies differ with respect to the length of the involucre, inner phyllary length, pappus length, corolla length (the latter subspecies being typically smaller than the former), chromosome number, reproductive biology, and (in part) provenance. Antennaria frieseana ssp frieseana is an agamospermous polyploid, represented by pentaploid (2n = 70) and hexaploid (2n = 84) cytotypes. Antennaria frieseana ssp. alaskana is sexual, probably partially agamospermous (tetraploid cytotype), and either diploid (2n = 28) or tetraploid (2n = 56). Key words: Antennaria frieseana, morphological variation, apomicts, sexual, agamospermy.

Gender dependent and independent morphological dimorphism in sexual and apomictic Antennaria monocephala sensu lato

1991 ◽  
Vol 69 (7) ◽  
pp. 1433-1448 ◽  
Author(s):  
J. G. Chmielewski ◽  
C. C. Chinnappa
Keyword(s):  
Chromosome Number ◽  
Key Words ◽  
Reproductive Biology ◽  
Chromosome Numbers ◽  
Evolutionary History ◽  
Multivariate Analyses ◽  
Reproductive Mode ◽  
Polyploid Complex ◽  
Adaxial Surface ◽  
History Of

Taxa included in the Antennaria monocephala DC. polyploid complex were previously circumscribed at the specific, subspecific, or varietal levels without concensus. The purpose of this phenetic study was to construct a taxonomy that not only reflects the presumed evolutionary history of the complex but also presents a taxonomy that is both functional and informative, regardless of an individual's gender or more importantly, the reproductive mode of the population. The rank of subspecies (A. monocephala ssp. monocephala and A. monocephala ssp. angustata (Green) Hultén) was accepted as the most appropriate level of gender independent circumscription that satisfied the purpose of the phenetic study. These subspecies differ with respect to tomentum, chromosome number, reproductive biology, and (in part) provenance. The former taxon, A. monocephala ssp. monocephala, is a sexual diploid (2n = 28); the latter taxon, A. monocephala ssp. augustata, is an apomictic polyploid, with chromosome numbers ranging from tetraploid (2n = 56) to octoploid (2n = 112). In A. monocephala ssp. monocephala the adaxial surface of the basal and cauline leaves is glabrous-strigose, as is the stem. In A. monocephala ssp. angustata the adaxial surface of both basal and cauline leaves is floccose-tomentose, as is the surface of the stem. Key words: Antennaria monocephala polyploid complex, multivariate analyses.

scholarly journals A taxonomic revision of the genus Cleome L. (Capparaceae) in Bangladesh

1970 ◽  
Vol 14 (1) ◽  
pp. 25-36
Author(s):  
Hosne Ara ◽  
Bushra Khan ◽  
Md. Mansur-ul-Kadir Mia
Keyword(s):  
Chromosome Number ◽  
Key Words ◽  
Geographical Distribution ◽  
Taxonomic Revision ◽  
Economic Importance ◽  
Plant Taxon

The available record of the genus Cleome L. for Bangladesh has been updated in this paper and includes C. diffusa, C. gynandra, C. hassleriana, C. rutidosperma and C. viscosa. The updating has been done in case of nomenclature with important synonyms, local names, description of the taxa along with illustrations, flowering and fruiting times, ecological notes, specimens examined and their geographical distribution. For identification of the species, a dichotomous bracketed key has been added in this paper. Information on chromosome number and economic importance have also been provided where available. Key words: Cleome, Taxonomic revision, Capparaceae, Bangladesh DOI: 10.3329/bjpt.v14i1.520 Bangladesh J. Plant Taxon. 14(1): 25-36, 2007 (June)

Changes in DNA content and chromosome number during spermatogenesis in the gall midge Monarthropalpus buxi (Cecidomyiidae, Diptera)

Genome ◽  
1992 ◽  
Vol 35 (2) ◽  
pp. 244-250 ◽  
Author(s):  
B. Jazdowska-Zagrodzinska ◽  
R. Dallai ◽  
C. A. Redi
Keyword(s):  
Chromosome Number ◽  
Key Words ◽  
Meiotic Division ◽  
Dna Content ◽  
Germ Line ◽  
Gall Midge ◽  
Key Words Dna ◽  
Further Development

In this paper we analyze the course of spermatogenesis in Monarthropalpus buxi. The first meiotic division occurs without any chromosomes pairing. As a result one spermatocyte II appears from which two sperms originate, and one residual cell, which does not undergo any further division. We found variations in chromosome number and DNA content between germ line cells of different individuals. Such variations were observed in the spermatocytes I and II, and in the sperms. In contrast, the residual cells, which did not take part in further development, always had the same DNA content and constantly inherited 20 chromosomes: 4 constituting one haploid set of the somatic type (S chromosomes) and 16 of the germ line limited type (E chromosomes).Key words: DNA content, chromosome number, Cecidomyiidae, germ line, spermatogenesis.

Polyploidy in Sporobolus virginicus (L.) Kunth

1979 ◽  
Vol 27 (4) ◽  
pp. 429 ◽  
Author(s):  
AR Smith-White
Keyword(s):  
Salt Marsh ◽  
Chromosome Number ◽  
Meiotic Division ◽  
Distribution Patterns ◽  
Meiotic Behaviour ◽  
Polyploid Complex ◽  
South Eastern ◽  
Sporobolus Virginicus ◽  
Eastern Australia ◽  
Tetraploid Cytotypes

Chromosome number and meiotic behaviour was examined in Sporobolus virginicus Kunth from south-eastern Australia. Var. minor Bail. forms a polyploid complex with diploid (2n = 20), triploid and tetraploid cytotypes. Meiosis in tetraploid plants of this variety is substantially normal, which indicates an alloploid origin. Var. virginicus, which has been found only in the tetraploid state, has irregular meiotic division, which suggests autoploidy. Most cytotypes were collected from sandy and well-drained situations along the coast. However, tetraploid var. minor plants were generally found in poorly aerated salt marsh swamps. This apparent edaphic adaption of tetraploid cytotypes may be important in explaining distribution patterns.

scholarly journals Karyotype analysis with orcein and CMA in two species of Alocasia (Schott) G. Don (Araceae)

1970 ◽  
Vol 40 (1) ◽  
pp. 53-56 ◽  
Author(s):  
Syeda Sharmeen Sultana ◽  
Hosne Ara ◽  
Sheikh Shamimul Alam
Keyword(s):  
Chromosome Number ◽  
Key Words ◽  
Karyotype Analysis ◽  
Chromosome Complement ◽  
Taxonomic Status ◽  
The Other ◽  
First Report ◽  
Total Length ◽  
Internet Information ◽  
Chromosomal Length

Alocasia fallax Schott and A. odora (Roxb.) Koch (Araceae) were investigated cytogenetically to confirm their taxonomic status. There is no report of 2n chromosome number for A. fallax in the available literature and internet information. Therefore the 2n chromosome number (2n = 28) found in this study is probably the first report for A. fallax. Alocasia odora showed exactly double 2n chromosome number (2n = 56) from A. fallax. In addition to chromosome number, the other karyotypic features of A. odora were exactly double for that of A. fallax. The centromeric formulae of A. fallax was 24 m + 4 sm whereas it is just double in A. odora. Total length of 2n chromosome complement of A. odora (62.58 μm) was almost double to A. fallax. The range of chromosomal length of the two species was almost same. Moreover, A. odora plant is much taller than A. fallax. All of these data suggests that A. odora might be an autotetraploid of A. fallax which in course of evolution had undergone some changes in GC-rich repeats. Key words: Alocasia; CMA; Karyotype analysis DOI: http://dx.doi.org/10.3329/bjb.v40i1.7998 Bangladesh J. Bot. 40(1): 53-56, 2011 (June)

The taxonomy of the Viola nuttallii complex

1987 ◽  
Vol 65 (12) ◽  
pp. 2562-2580 ◽  
Author(s):  
D. M. Fabijan ◽  
J. G. Packer ◽  
K. E. Denford
Keyword(s):  
Chromosome Number ◽  
Phylogenetic Relationships ◽  
Basic Chromosome Number ◽  
Chemical Diversity ◽  
Statistical Analyses ◽  
Polyploid Complex ◽  
Basic Chromosome ◽  
Wide Range ◽  
Flavonoid Chemistry

Morphological, cytological, and phytochemical data were incorporated into numerical and statistical analyses to produce a revision of Viola subsection Nuttallianae. A basic chromosome number of x = 6 was confirmed for this polyploid complex, which includes five species: V. vallicola, 2n = 12; V. tomentosa, 2n = 12; V. nuttallii, 2n = 24; V. praemorsa, 2n = 36 and 48; and V. bakeri, 2n = 48. Departures from recent authors include the recognition of two varieties in V. vallicola, vallicola and major (Hook.) Fabijan, based on flavonoid chemistry and distribution. Viola praemorsa is envisaged as embracing a wide range of morphological and chemical diversity, the extremes of which are recognized as the subspecies praemorsa, flavovirens (Pollard) Fabijan, and linguaefolia. In the absence of significant morphological or distributional differences between the V. linguaefolia and V. praemorsa subspecies major (sensu Baker and Clausen) and oregona, these three previously recognized taxa are included in subspecies linguaefolia. Based on cytological, morphological, and flavonoid data presented here, possible phylogenetic relationships are discussed.

The biology of Canadian weeds. 119. Cannabis sativa L.

2003 ◽  
Vol 83 (1) ◽  
pp. 217-237 ◽  
Author(s):  
E. Small ◽  
T. Pocock ◽  
P. B. Cavers
Keyword(s):  
Law Enforcement ◽  
North America ◽  
Great Lakes ◽  
Key Words ◽  
Reproductive Biology ◽  
Cannabis Sativa ◽  
Biological Properties ◽  
Textile Fibre ◽  
Habitat Conditions ◽  
A Minor

Cannabis sativa has been cultivated for millennia in Eurasia and for centuries in North America, as a source of a textile fibre, oilseed, and intoxicating drugs such as marijuana. Considerable literature is available on the agricultural and biological properties of these basic three cultigens, but relatively little is published on wild-growing plants of the species. Most weedy C. sativa differ from the cultigens in a number of ecological properties, particularly with regard to reproductive biology. The species is the classical example of a “camp follower” that is exceptionally adapted to the habitat conditions around settlements: rich, highly manured, moist soils, and open areas resulting from recent removal or disturbance of the vegetation. In Canada, spontaneous populations have been found in all provinces, but forms that have re-evolved wild adaptations are concentrated along the St. Lawrence and lower Great Lakes. The ruderal plants pose a minor weed problem to agriculture but a major problem to law enforcement, and decades of eradication have exterminated many of the naturalized populations in Canada. With the recent re-authorization of hemp cultivation in Canada, it is inevitable that there will be additional escapes and a reinvigoration of the ruderal phase of the species. Mechanical eradication for 2 or 3 yr is effective at destroying populations, and young plants are easily eliminated by herbicide applications. Key words: Cannabis sativa, hemp, marijuana, marihuana, weed, oilseed

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.

scholarly journals Taxonomic revision of the genus Caesalpinia l. (Caesalpiniaceae) for Bangladesh

1970 ◽  
Vol 13 (2) ◽  
pp. 93-109
Author(s):  
BM Rezia Khatun ◽  
Mohammad Oliur Rahman
Keyword(s):  
Chromosome Number ◽  
Key Words ◽  
Taxonomic Revision ◽  
Economic Importance ◽  
Plant Taxon

The genus Caesalpinia L. represented by 12 species has been revised for Bangladesh. Dichotomous bracket key has been given for identification of the species. An updated nomenclature, description of the taxa along with illustrations, specimens examined, ecology, notes on distribution and economic importance have been provided. Chromosome number and ethnobotanical information have also been furnished in most cases. Key words: Caesalpinia, Taxonomic revision, Caesalpiniaceae, Bangladesh DOI: 10.3329/bjpt.v13i2.582 Bangladesh J. Plant Taxon. 13(2): 93-109, 2006 (December)

A clarification of Medicago sinskiae

1991 ◽  
Vol 69 (1) ◽  
pp. 100-106 ◽  
Author(s):  
Ernest Small ◽  
Brenda Brookes
Keyword(s):  
Chromosome Number ◽  
Key Words ◽  
Related Species ◽  
The Other ◽  
Species Status ◽  
Closely Related Species

Little information has been available to justify the species status of the rare Turkmenian Medicago sinskiae Uljan. recognized by Uljanova in 1964. The holotype and plants raised from its seeds were examined, the chromosome number was determined, and a numerical taxonomic comparison was made of M. sinskiae and the other 12 species of Medicago section Spirocarpos subsection Pachyspirae. It was found that M. sinskiae is well separated from the most closely related species of Medicago and deserves recognition at the rank of species. Key words: Medicago sinskiae, Leguminoseae, alfalfa, taxonomy.

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