Application of Karyotype and Genetic Characterization Analyses for Hybrid Breeding of Epinephelus Groupers

Abstract

In this study, karyotypes and Cyt b gene sequences of seven different species of grouper including Plectropomus leopardus, Epinephelus coioides, E. flavocaeruleus, E. fuscoguttatus, E. lanceolatus, E. polyphekadion,andE. tukulawere examined.All chromosomenumbers fromseven grouperswere 2n = 48with a high number of telocentric chromosomes (38–48) and fundamen- tal armnumbers (FNs) (48–54). ThemitochondrialCytbgenewasused toestablish thebarcodes of seven groupers and analyze phylogenetic relationships among these species.We discovered that Epinephelus groupers should be classified as monophyly. The minimum genetic distance expressed between E. coioides and E. tukula was 0.1276. From results of the cytogenetic and molecular analyses, it was demonstrated that Plectropomus is a relatively primitive genus of grouper, whileEpinephelus is amore-modern derivedgenus. Results also showed that E. coioides and E. tukula have similar genetic characters and karyotypes, and should be foremost consid- ered for artificial hybridization strategies. Furthermore, information on karyotypes of species within the Epinephelus is still insufficient, and further elucidation of karyotypes of Epinephelus will be a great help to future genetic breeding research