Abstract:Triploid induction of Argopectens irradias (Lamarck) was achieved through inhibiting the second polar body release by soaking fertilized eggs in sea water with low salinity, and the effect of different salinity treatment on triploid induction was examined. When 40％ eggs reached the first polar body stage, the eggs were soaked in sea water with salinities of 30, 22.5, 20, 17.5, 15, 12.5, 10 and 7.5 for 10 min or 15 min respectively. The eggs were then transferred into the normal salinity seawater for 24h hatching. Triploid rate was no more than 2.91% when the salinity was above 20. However, with the decrease of salinity, triploid induction was enhanced so dramatically that the rate of triploid reached up to 85.91％ at salinity of 12.5. Though, when the salinity was below 7.5, due to the lack of D-shaped larvae, the triploid rate could not be measured. The results show that the induction effect of 15 min treatment is better than 10 min. The experiment results suggest that the best triploid induction of A. irradias is achieved by bathing in seawater at salinities of 12.5~15 for 15 min.KEY WORDSArgopectens irradiasLow salinityTriploidD shaped larvae hatching rate
