This work aimed to characterize the karyotype of six species of native fruits from Brazil through number and chromosome morphology analysis. The young root tips were pretreated with 8-hydroxiquinolin 0.002M, squashed in 45% acetic acid, and conventionally stained with Giemsa. All species showed symmetrical karyotype with small chromosomes and 0.6-2.5µm of length, mainly meta to sub-metacentric ones with one to two secondary visible constrictions in all species, except in Bromelia karatas in which it was not possible to identify the chromosome morphology or the presence of secondary constrictions. In Myrtaceae family, it had been observed a diploid chromosome supplement with 2n=98 in Psidium arboretum Vell. and 2n=44 in P. araça Raddi; 2n=50 in Bromelia karatas L.; in the Malvaceae, 2n=16 for Guazuma ulmifolia Lam.; in Sapindaceae, 2n=32 in Talisia esculenta Radlk. and, in Caricaceae, 2n=18 in Jaracatia spinosa (Aubl.) A. DC. All chromosome data presented in this work have been karyologically unpublished, except for T. esculenta which had previous reports confirmed. The species are potentially useful in breeding systems, and a heterozygosis inversion seems to be involved in the karyotype evolution of Guazuma ulmifolia.
Karyological evolution; chromosome invertion; late condensation
