CHROMOSOME NUMBER OF TWO MEXICAN SPECIES OF THE Diospyros GENUS, ZAPOTE PRIETO (EBENACEAE)

Abstract

Chromosome counting was carried out in two mexican species of the Diospyros genus, (zapote prieto) of Ebenaceae family, Diospyros xolocotzii Madrigal & Rzed. and Diospyros digyna Jacq. The cytogenetic analysis was performed in somatic cells of root tips pretreated with a saturated solution of para-dichlorobenzene, for 4 h at 4 °C and fixed in Carnoy. The chromosomes staining was obtained with Feulgen and 1 % acetic carmine. The results obtained show that the chromosome number for both species was 2n = 2x = 30, which indicates that these two species are diploid, as the chromosome numbers reported for this genus in most species is 2n = 2x = 30, with a basic number x = 15.