Chromosome Karyotype Analysis of Hybrids of Epinephelus moara♀×Epinephelus lanceolatus♂

Abstract:

In this research, the chromosomal preparation and karyotype of Epinephelus moara♀ × Epinephelus lanceolatus♂ hybrid progeny (commonly known as Yunlong grouper) were studied. The juvenile fish weighing 60~100 g were injected subcutaneously with 6 μg/g phytohemagglutinin (PHA) and 0.1‰ colchicine. After 21 h, the head kidney and gill were dissected for cell suspensions, slices of their chromosome split phase were made by cold and hot drop method combing with air-drying. After being stained with 10% Giemsa, a clear and complete split phase was screened under a microscope. Chromosomes in 75 mitotic phases were selected and the karyotype analysis was performed. The results showed that the karyotype formula was determined to be 2n=48, 4sm+6st+38t, NF=58 in Yunlong grouper. Hybrids Yunlong grouper had the same chromosome number with their parents (2n=48), but their karyotype was different, indicating the complex chromosomal recombination and mutation occurred in the genetic process. This study provided an important scientific basis for the germplasm identification genetic relationship analysis and crossbreeding of Yunlong grouper.