The Israeli Journal of Aquaculture - Bamidgeh 52(1), 2000, 11-20
EARLY HEAT-SHOCK INDUCED DIPLOID GYNOGENESIS IN
COMMON CARP (CYPRINUS CARPIO L.)
Tariq A. Khan, Minal P. Bhise and W.S. Lakra
Fish Genetics and Biotechnology Division, Central Institute of Fisheries Education (CIFE), Mumbai 400 061, India
(Received 14.10.99, Accepted 14.5.00)
A reliable method for inducing meiotic diploid gynogenesis in the common carp, Cyprinus carpio (L.) was developed, using heat shock treatment of eggs fertilized with UV-irradiated sperm. Haploid and diploid fry were identified by morphological appearance, karyological examination, color pattern
transformation and number of nucleoli per nucleus. Haploid fry were totally deformed and died within 10 days after hatching. UV-irradiation of 30 min was optimum for genetic inactivation of common carp sperm. Eggs fertilized with UV-irradiated sperm and subjected to heat shock at 40°C for 2 min, 3 min after fertilization, resulted in 100% diploid gynogenetic fry. In terms of embryological age, the time after insemination was 0.22 t 0. This study revealed that temperature and post-insemination time play a significant role in the induction of diploid gynogenesis in common carp (p <0.05).