English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/110244
Compartir / Impacto:
Add this article to your Mendeley library MendeleyBASE
 |  Ver citas en Google académico
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar otros formatos: Exportar EndNote (RIS)Exportar EndNote (RIS)Exportar EndNote (RIS)

Physical mapping of ribosomal DNA and genome size in diploid and polyploid North African Calligonum species (Polygonaceae)

Autor Gouja, Hassen; Garnatje, Teresa ; Hidalgo, Oriane ; Neffati, Mohamed; Raies, Aly; Garcia, Sònia
Palabras clave 5S rDNA
35S rDNA
Fluorochrome banding
Genome organization
Fecha de publicación 29-nov-2014
Citación Plant Systematics and Evolution
ResumenMost Calligonum species are desert plants, characteristic of the Saharan bioclimatic region. All species karyologically analyzed until present have the basic chromosome number x = 9 and comprise diploids, triploids and tetraploids. The Tunisian flora comprises diploid Calligonum arich and C. azel, of restricted distribution, and the tetraploid C. comosum with wider distribution. Analyses of their karyotypes and polyploidisation-linked rDNA changes by orcein staining, fluorochrome banding with chromomycin A3 and fluorescent in situ hybridisation with 5S and 26S ribosomal DNA probes have been performed. We report the chromosome number for Calligonum arich (2n = 18) as well as the diploid level for C. comosum for the first time. Chromosome counts have also verified the earlier described tetraploid cytotype (2n = 36) of C. comosum. A general pattern of six GC-rich bands as well as two 35S sites and four 5S sites is described for Calligonum species at the diploid level although there is intraspecific variation regarding the site number in a second type of C. comosum, with one pair of 35S rDNA sites and two pairs of 5S rDNA sites. The tetraploid cytotype of C. comosum has undergone locus loss and genome downsizing. Genome size assessments confirmed previous data. Nonetheless, statistically significant differences were found depending on the type of tissue used for estimation. Measurements from seeds had always larger values than from leaves. The presence of cytosolic compounds in leaves, interfering with DNA staining, is discussed as a possible cause of the differences.
Descripción 38 p., tablas, gráf.
Versión del editorhttp://dx.doi.org/10.1007/s00606-014-1183-9
URI http://hdl.handle.net/10261/110244
Aparece en las colecciones: (IBB) Artículos
Mostrar el registro completo

NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.