Número cromossômico de três espécies nativas que ocorrem na Amazônia Meridional / Chromosome number of three native species occurring in the Southern Amazon

A cytotaxonomic treatment is given for 12 native species, 2 introduced species, and 3 natural interspecific hybrids of the genus Elymus L. that occur in Canada. Five of the native Elymus species and an additional natural interspecific hybrid are found in Alaska. Eleven of the native species, one introduced species, and two of the natural interspecific hybrids are present in the mainland United States. Some additional native species and natural interspecific hybrids of Elymus from the mainland United States are treated briefly.Nomenclatural proposals include: Elymusglaucus Buckl. var. virescens (Piper) Bowden; E. ×uclueletensis Bowden (E. mollis Trin. f. mollis × E. glaucus Buckl. var. glaucus); E. × aleuticus Hultén (pro sp.) (E. mollis Trin. f. mollis × E. hirsutus Presl); E. canadensis L. var. wiegandii (Fern.) Bowden f. wiegandii and f. calvescens (Fern.) Bowden; E. ×maltei Bowden nm. maltei, nm. simulans Bowden, nm. churchii Bowden, and nm. brownii Bowden (E. virginicus L. × E. canadensis L.); E. virginicus L. var. jenkinsii Bowden; E. hystrix L. var. bigelovianus (Fern.) Bowden; E.piperi Bowden; E. innovatus Beal subsp. innovatus var. glabratus Bowden; and E. triticoides Buckl. var. pacificus (Gould) Bowden. Hystrixpatula Moench is here treated as Elymushystrix L.Voucher specimens are cited for the following chromosome number determinations:(1) diploid, 2n = 14: Elymusjunceus.(2) tetraploid, 2n = 28: Elymus canadensis var. canadensis, E. canadensis var. wiegandii f. wiegandii, E. diversiglumis, E. glaucus var. glaucus, E. glaucus var. virescens, E. hirsutus, E, hystrix var. hystrix, E. hystrix var. bigelovianus, E. innovatus subsp. innovatus var. innovatus, E. × maltei nm. maltei, E. riparius, E. sibiricus, E. villosus f. villosus, E. virginicus var. virginicus f. virginicus, and E. virginicus var. submuticus.Earlier literature reports (based on voucher specimens) are given for the following:(1) tetraploid, 2n = 28: Elymus mollis (two subsp. and three forms), E. piperi, and E. × vancouverensis nm. crescentianus.(2) hexaploid, 2n = 42: Elymus × vancouverensis nm. vancouverensis, and E. × vancouverensis nm. californicus.(3) octoploid, 2n = 56: Elymus arenarius, E. innovatus subsp. velutinus, and E. piperi.

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The biosystematics of the genus Lotus (Leguminosae) in Canada. II. Numerical chemotaxonomy

Canadian Journal of Botany ◽

10.1139/b68-084 ◽

1968 ◽

Vol 46 (5) ◽

pp. 585-589 ◽

Cited By ~ 19

Author(s):

William F. Grant ◽

Ilse I. Zandstra

Keyword(s):

Chromosome Number ◽

Thin Layer ◽

Native Species ◽

Cytological Study ◽

Diploid Species ◽

Basic Chromosome Number ◽

Chromatographic Study ◽

Chemical Identification ◽

Basic Chromosome ◽

Fluorescent Compounds

A thin-layer chromatographic study of fluorescent compounds present in native (L. denticulatus, L. formosissimus, L. micranthus, L. pinnatus, L. purshianus) and introduced (L. corniculatus, L. krylovii, L.pedunculatus, L. tenuis) Canadian species of Lotus has been carried out and relationships of the species have been determined on the basis of the coefficients of association of these compounds. Chemical identification of the compounds was not attempted, but test reagents indicated a number to be phenolics. The analysis supported the general taxonomic relationships of the species based on a morphological and cytological study. Of the native species, L. pinnatus and L. formosissimus were the most closely related, with a coefficient of association of 83.33. Lotus denticulatus, the only native species with a chromosome number of n = 6, in general showed lower coefficients of association with the n = 7 species. Of the introduced species, all of which belong to the L. corniculatus group with a basic chromosome number of 6, L. krylovii and L. tenuis had the highest coefficient of association, 75.86. Based on their coefficients of association, both of these diploid species were more closely related to the tetraploid L. corniculatus than to the diploid L. pedunculatus.

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Polyploidy in Paullinia (Paullinieae, Sapindaceae) and its Systematic Implications

Systematic Botany ◽

10.1600/036364420x16033962925196 ◽

2020 ◽

Vol 45 (4) ◽

pp. 873-878

Author(s):

Juan D. Urdampilleta ◽

Eliana R. Forni-Martins ◽

María S. Ferrucci

Keyword(s):

Chromosome Number ◽

South America ◽

Native Species ◽

Chromosome Counts ◽

Polyploid Series ◽

First Time

Abstract—Chromosome counts from 23 populations of 16 species of Paullinia (Paullinieae, Sapindaceae) from South America are given. These include first counts for ten species in six of the thirteen sections of this genus. Counts of 2n = 24 for P. cristata, P. revoluta, P. thalictrifolia, P. trigonia, P. uloptera, P. rhomboidea; 2n = 48 for P. seminuda and P. sp.; and two cytotypes of 2n = 48 and 2n = 96 for P. carpopoda and P. rubiginosa; and ca. 2n = 216 for P. cupana var. sorbilis. The chromosome number 2n = 24 appears to be conserved for this genus, however, in this contribution polyploid series are cited for the first time for some native species. These results were interpreted in a phylogenetic context.

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CYTOTAXONOMY OF THE SPECIES AND INTERSPECIFIC HYBRIDS OF THE GENUS AGROPYRON IN CANADA AND NEIGHBORING AREAS

Canadian Journal of Botany ◽

10.1139/b65-151 ◽

1965 ◽

Vol 43 (11) ◽

pp. 1421-1448 ◽

Cited By ~ 28

Author(s):

Wray M. Bowden

Keyword(s):

United States ◽

Chromosome Number ◽

Introduced Species ◽

Chromosome Numbers ◽

Interspecific Hybrid ◽

Native Species ◽

Interspecific Hybrids ◽

Natural Hybrids ◽

Voucher Specimens ◽

First Time

A cytotaxonomic treatment is given for 10 native species, 4 introduced species, and 8 natural interspecific hybrids of the genus Agropyron Gaertner that occur in Canada. Five of the native Agropyron species, one introduced species, and one natural interspecific hybrid are also found in Alaska. Eight of the native species, the four introduced species, and four natural interspecific hybrids are present in the mainland United States. Four additional native species and five additional introduced species that occur in the mainland United States are considered briefly.Nomenclatural proposals include: Agropyron dasystachyum (Hook.) Scribn. var. riparium (Scribn. & Smith) Bowden; Agropyron × pseudorepens Scribn. & Smith (pro sp.) nm. pseudorepens and nm. vulpinum (Rydb.) Bowden (A. dasystachyum × A. trachycaulum); and Agropyron × brevifolium Scribn. (pro sp.) (A. scribneri × A. violaceum).Voucher specimens are cited for chromosome number determinations of the native and introduced Agropyron species and some natural and artificial interspecific hybrids. Chromosome numbers are reported for the first time for A. violaceum (2n = 28), A. yukonense (2n = 28), the natural hybrids A. × pseudorepens nm. pseudorepens and nm. vulpinum (2n = 28), A. dasystachyum × A. spicatum (2n = 21), and A. violaceum × A. yukonense (2n = 28), and four artificial interspecific hybrids. Seven natural hybrids and four artificial hybrids are reported for the first time.

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Senecio L. (Asteraceae) in Australia: Rcombination systems of a polyploid series

Australian Journal of Botany ◽

10.1071/bt9850209 ◽

1985 ◽

Vol 33 (2) ◽

pp. 209 ◽

Cited By ~ 10

Author(s):

M.E. Lawrence

Keyword(s):

Chromosome Number ◽

Breeding System ◽

Chromosome Numbers ◽

Native Species ◽

Polyploid Species ◽

Ploidy Levels ◽

Basic Chromosome ◽

High Polyploid ◽

Evolutionary Changes ◽

Extreme Phenotypes

Recombination systems of 32 species of Senecio are discussed in terms of chromosome number, chiasma frequency and position, breeding system and generation length. Darlington's recombination index cannot be applied to Senecio as several ploidy levels are represented. Increases in basic chromosome numbers promote recombination but increases by polyploidy buffer intermediate genotypes and retard evolutionary changes when selection is for homozygous or extreme phenotypes. High polyploid species of Senecio may therefore have recombination systems as restrictive as those produced by aneuploid reduction. When viewed in this manner, the majority of native species examined have recombination systems that contain a balance of restrictive and expansive factors regulating recombination.

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