Insights on cytogenetic of the only strict African representative of genus Prunus (P. africana): first genome size assessment, heterochromatin and rDNA chromosome pattern

Abstract

Prunus africana is a multipurpose evergreen species endemic to Africa and an endangered species because of overexploitation. The great importance of this species resides particularly in the use of its bark against benign prostatic hyperplasia. As for most tropical trees and generally woody species, cytogenetic studies are scarce. Standard and molecular cytogenetic approaches have been implemented for the first time to study P. africana from Cameroon. This is the tetraploid species with a chromosome number of 2n=4x=32. Genome size estimated by flow cytometry was 2C=1.44 pg. Five loci (ten signals) of 35S rRNA genes were observed after fluorescence in situ hybridization. Ten G-C rich DNA regions were detected by chromomycin A3 fluorochrome banding. All chromomycin positive bands were co-localized with 35 S rDNA signals. Prunus africana, the only strict African representative of genus Prunus, is in need of the conservation strategy and in situ management that we are also discussing in this work.

Keywords

• Chromomycin fluorochrome banding
• chromosome number and 2C DNA value
• fluorescent in situ hybridization (FISH)
• heterochromatin and rRNA gene patterns