Darwiniana, nueva serie
versión On-line ISSN 1850-1699
TAPIA-PASTRANA, Fernando. Citogenetics of Guazuma ulmifolia var. ulmifolia (Sterculiaceae). Darwiniana [online]. 2007, vol.45, n.1, pp. 23-27. ISSN 1850-1699.
A surface spreading and air-drying method to obtain for the first time the somatic karyotype of a population of Guazuma ulmifolia var. ulmifolia was used. Chromosome diploid number of 2n = 16 from meristematic root cells was confirmed. Mitotic karyotype was 14m + 2st with a slight asymmetry (T.F.% = 42.19). Total haploid chromosome length was 11.65 µm with a chromosomal interval of 1.11 - 2.05 µm. Nucleolar organizers were associated to secondary constrictions on the pair 3 (m), and a polymorphism was observed on the pair 8 (st). These two features could be employed as cytogenetic markers in future studies for other species and varieties of the genus.
Palabras llave : Guazuma; karyotype; Mexico; Nucleolar organizers; Sterculiaceae.