Formation of embryonic genomes in hybrid triploid loach×diploid loach
LIANG Yu-ting1, SUI Yi 2, ZHUANG Zi-xin1, XU Qi-zheng1, ZHANG Rui1, ZHOU He1
1.Key Laboratory of Marine Bio-resources Restoration and Habitat Reparation in Liaoning Province, Key Laboratory of Marine Bio-resources Sustainable Utilization in Liaoning Province’s University, Key Laboratory of Mariculture & Stock Enhancement in North China’s Sea, Ministry of Agriculture, Dalian Ocean University, Dalian 116023, China; 2.Ma’anshan Muncipal Agriculture Commission, Ma’anshan 243000, China
Abstract: The embryo chromosomes were investigated in hybrid triploid loach Misgurnusanguillicaudatus×diploid loach prepared cross combinations of 2n♀×3n♂ and 3n♀×2n♂ by silver straining, chromomycin A3(CMA3), and fluorescence in situ hybridization(FISH) to explore the formation of gamete genomes for hybrid triploid loach (2n×4n). Results showed that the both hybrid offsprings had the maximum silver staining point of 3 at the end of the metacentric chromosome (M1)during the mitotic metaphase. There were CMA3 positive in the highest mitotic metaphase 3 regions of 2n♀×3n♂ and 3n♀×2n♂ hybrids, and 5.8S+28S rDNA was located at the embryo chromosome of hybrid offspring. Three hybridization signals were found at the end of metacentric chromosome (M1) in the two cross combinations, indicating that 3 genomes were formed by hybridization between the hybrid triploid loach, whether male or female, and it is speculated that the hybrid triploid loach, for either male or female, will produce (1.5-2)n gamete. The findings provide cytogenetic evidence for the chromosome composition of triploid loach gamete genomes.
2018, Vol. 33 
