Mixoploidy and cytotypes: a study of possible vegetative species differentiation in stapeliads (Asclepiadaceae)

Bothalia - African Biodiversity & Conservation

 
 
Field Value
 
Title Mixoploidy and cytotypes: a study of possible vegetative species differentiation in stapeliads (Asclepiadaceae)
 
Creator Albers, F. Meve, U.
 
Subject — adventitious roots. Asclepiadaceae. cytotypes. euploidy, growth forms; mixoploidy. Stapelieae
Description Mixoploidy is common in proembryos and embryos as well as in meristems of radicles, primary, secondary and adventitious roots and in innovation shoots of stapeliad species (Asclepiadaceae). The proportion of polyploid cells in the meristem of single adventitious roots is significantly higher than in meristems of primary and secondary roots. This may lead to a complete polyploidisation of adventitious roots. Innovation shoots display a low percentage of polyploid cells, comparable to the condition found in primary and secondary roots. Nevertheless cells of different euploid levels are frequently found. During field studies, however, individuals of a given population were always found to have the same chromosome number: infraspecific polyploidy was found in only three out of 305 investigated stapeliad species. Genera with an orthotropic growth form were found to be diploid throughout, whereas the genera of which the members spread vegetatively by means of innovation shoots, comprise di-, tetra- and polyploid species. This phenomenon can be ascribed to ecological rather than morphological factors. The often proposed hypothesis that new cytotypes can have a vegetative origin is not found to be acceptable.
 
Publisher AOSIS
 
Contributor
Date 1991-09-22
 
Type info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion — —
Format application/pdf
Identifier 10.4102/abc.v21i1.867
 
Source Bothalia; Vol 21, No 1 (1991); 67-72 2311-9284 0006-8241
 
Language eng
 
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The following web links (URLs) may trigger a file download or direct you to an alternative webpage to gain access to a publication file format of the published article:

https://journals.abcjournal.aosis.co.za/index.php/abc/article/view/867/820
 
Coverage — — —
Rights Copyright (c) 1991 F. Albers, U. Meve https://creativecommons.org/licenses/by/4.0
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