Induced Gynogenesis in Grass Carp (Ctenopharyngodon idellus) Using Irradiated Sperm of Allotetraploid Hybrids
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Grass carp (Ctenopharyngodon idellus) eggs were activated by UV-irradiated diploid sperm of allotetraploid hybrids derived from red crucian carp (♀) × common carp (♂) and then duplicated by cold shock in 4–6°C water for 10–12 min. Different cold shock initiation times resulted in two types of diploid gynogenetic grass carp: meiotic gynogenetic (meiG) and mitotic gynogenetic (mitG). Over a 5-year period, a total of 17,170 meiG and 1,080 mitG fry were produced and 6,862 meiG and 372 mitG grass carp survived. The gynogenetic fish were confirmed by morphological characteristics, chromosome examination, and microsatellite DNA analysis. The morphological traits of the gynogenetic grass carp were similar to those of wild diploid grass carp. Normal gynogenetic fish were identified as diploid with 48 chromosomes by chromosomal metaphases examination, while nonviable abnormal embryos were detected as haploid with 24 chromosomes. Microsatellite DNA analysis indicated that after one generation of gynogenesis, the genetic purity of meiG and mitG grass carp was significantly increased over that of wild grass carp. In addition, both meiG and mitG grass carp groups were 100% female, and 88% of these showed normal ovary development. Thus, the sex determination mechanism in female grass carp was homogamety. The ability to establish pure all-female groups of meiG and mitG grass carp should be a valuable contribution to both fish genetics and grass carp breeding.
KeywordsGrass carp Gynogenesis Microsatellite Sex determination
This research was supported by grants from the National Science Fund for Distinguished Young Scholars (no. 30725028), the National Natural Science Foundation of China (no. 30930071), and the State Key Basic Research Project of China (abbreviate: 973 project, grant no. 2007CB109206).
- Liu Y (1993) Propagation physiology of main cultivated fish in China. Agricultural Publishing House, Beijing, pp 83–88Google Scholar
- Sambrook J, Fritsch EF, Maniatis T (1989) Molecular cloning: a laboratory manual, 2nd edn. Cold Spring Harbor Laboratory, New YorkGoogle Scholar
- Sun YD, Zhang C, Liu SJ, Tao M, Zeng C, Liu Y (2006) Induction of gynogenesis in Japanese crucian carp (Carassius cuvieri). Chin J Genet 33:405–412Google Scholar