CYTOGENETIC ANALYSIS OF GLOBAL POPULATIONS OF MUGIL CEPHALUS (STRIPED MULLET) BY DIFFERENT STAINING TECHNIQUES AND FLUORESCENT IN SITU HYBRIDIZATION

摘要

The present paper reports the results of cytogenetic analysis carried out on several scattered populations of the striped mullet, Mugil cephalus, the most widespead among mugilid species. The karyotype was investigated through Ag-staining, C-banding, fluorochrome-staining (chromomycin A(3)/DAPI) and fluorescent in situ hybridization with rDNA genes. All populations showed the same chromosome number and morphology and no changes were detected in heterochromatin and NORs. Therefore, neither population- nor sex-specific marker chromosomes were identified. In some of the specimens, NOR size heteromorphism was detected. Results are discussed with respect to karyotype and ribosomal cistrons organization and to cytotaxonomic implications.