Abstract
A cytogenetic survey of 17 species in the succulent-leaved genus Aloe L. (Xanthorrhoeaceae subfamily Asphodeloideae) in Ethiopia was undertaken towards a more complete genetic characterisation of the genus throughout its distribution in Africa, Arabia and Madagascar. Somatic metaphase chromosomes of all species studied showed the same diploid chromosome number of 2n = 14, consisting of four pairs of long and three pairs of short chromosomes. Symmetry was characterised as Stebbins type 2B and the asymmetry indices AsK%, TF%, A1 and A2 revealed minor karyotypic variation common in closely related species. The metrics showed that A. benishangulana has a marginally higher degree of asymmetry than is typical, and the pubescent-flowered A. trichosantha has a more symmetrical karyotype than most other species. We suggest that the stable karyotype morphology in Aloe indicates that structural genome changes and ecological factors play a more prominent role in speciation in Aloe.
Original language | English |
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Journal | Kew Bulletin |
Volume | 68 |
Issue number | 4 |
Pages (from-to) | 599-607 |
Number of pages | 9 |
ISSN | 0075-5974 |
DOIs | |
Publication status | Published - Dec 2013 |