Tetraploid induced by physical and chemical methods in Jinjiang oyster(Crassostrea rivularis)

In order to induce tetrapkrid into Jinpang oyster (Crassostrea rivularis),embryos were treated with physical (cokl or heat shock) and chemical (chlorpromasinum or traditional Chinese medicine) methods in the first 3 min before the cleavage of zygotes or at the onset of the first cleavage of one or two eggs.Measurements show that the induction rates of tetraploid in the embryos inspected are 28%,30%,28.4% and 35.8% for heat-shock (39℃,3 min), cold-shock (10℃,3 min), chlorpromazinum (0.375 mg/dm³, 10 min) and traditional Chinese medicine (50 g/dm³) extract (57 cm³, 10 min), respectively.The tetraploid induction rate in the larvae treated with traditional Chinese medicine is 32.5%.
It is evident that the induction rate of tetraploid in embryos inspected at an early stage is the most remarkable when treated with traditional Chinese medicine.