The lsraeli Joumal of Aquaculture - Bamidgeh 50(3), 1998, 99-110
CHROMOSOME SET MANIPULATIONS AND HYBRIDIZATION
EXPERIMENTS IN GILTHEAD SEABREAM (SPARUSAURATA).
1. INDUCED GYNOGENESIS AND INTERGENERIC HYBRIDIZATION USING
MALES OF THE RED SEABREAM (PAGRUS MAJOR)
Sergei Gorshkov, Galina Gorshkova, Aliza Hadani, Hillel Gordin and Wayne Knibb
Genetics Department, Israel Oceanographic and Limnological Research,
National Center for Mariculture, P.O. Box 1212, Elat 88112, Israel.
tel. 972-7-6361458, fax 972-7-6375761
(Received 14.7.97, Accepted 6.6.98)
The parameters for the production of triploid and gynogenetic progenies of the gilthead sea bream, Sparus aurata, have been established. To induce diploidization of the maternal genome the optimal heat shock temperature used was 36.5-37.3° C. Time after fertilization for shock treatment and duration of shock were 3 and 2.5 min, respectively. Triploidization efficiency in embryos was positively associated with shock temperature, reaching a maximum of 100% at 37°C. Gynogenetic diploid progenies of S. aurata were produced using the same conditions established for triploidization, except that fertilization was carried out with UV-inactivated heterologous sperm of red sea bream, Pagrus major. The efficiency of the sperm inactivation was estimated to be 100%. Diploid and triploid hybrids between S. aurata females and P. major males were produced. The chromosome "markers" useful in interspecific hybridization experiments are discussed.