IMBIV 05474
INSTITUTO MULTIDISCIPLINARIO DE BIOLOGIA VEGETAL
Unidad Ejecutora - UE
artículos
Título:
Karyotypes and fluorescent chromosome banding in Pyrrhocactus (Cactaceae).
Autor/es:
LAS PEÑAS L.; BERNARDELLO G.; KIESLING R.
Revista:
PLANT SYSTEMATICS AND EVOLUTION
Editorial:
Springer
Referencias:
Año: 2008 vol. 272 p. 211 - 222
ISSN:
0378-2697
Resumen:
Karyotypes of the seven Pyrrhocactus species were studied for the first time with Feulgen stainingand CMA3/DAPI banding. All showed 2n = 22 (x =11).The karyotypes were symmetrical with 9m + 2sm pairs,excepting P. catamarcensis with 8m + 2sm + 1st pair. They had a terminal microsatellite on short arms ofpair #1. P. bulbocalyx possessed a second satellited pair exclusively detected with Feulgen. Increasingasymmetry was associated with a decline in genome size. Fluorochrome banding, applied for the first time inCactaceae, revealed that nucleolar chromosome pair #1 had one CMA+/DAPI- terminal band in all species;additional pericentromeric bands were found. A pattern of homogeneous sized chromosomes with medianand submedian centromeres is conserved in the genus. However, karyotypes can be distinguished by acombination of cytogenetic features. Species diversification has not been associated with large chromosomerearrangements or polyploidy, but with cumulative small and cryptic structural changes.
