Simi-Artificial Spat Collection Technology Of Crassostrea Hongkongensis Of The Guangxi Maowei Sea

30billion oyster spats, which is the main source of oyster spat breeding in the coastal region of South China,are collected by the simi-artificial spat collection technology in Maowei Sea of Guangxi every year.lt is the main source of oyster spat breeding in the coastal region of South China.For a long time,based primarily on breeding experience, the traditional method of oyster spat collection,which makes the effect not stable and species not pure enough,directly restricted the development of oyster aquaculture industry in Guangxi. Researching the oyster spat species composition, the cycle time of oyster breeding season and the regular of oyster larvae quantity dynamic in Maowei Sea, and setting up the scientific simi-artificial spat collection technology of C.hongkongenis can contribute greatly to improving the effect of simi-artificial C.hongkongenis spat collection in Maowei Sea.Oyster adults, juvenile and larvae were identified by multiple PCR technology in this study.External morphology and gonad tissue slice of mature C.hongkongenis were observed.The oyster larvae quantity,water temperature, salinity, pH and the weather condition were monitored in the C.hongkongenis breeding season.The research showed that,the proportion of C.hongkongensis was more than97.5%both in all different breeding peaks of oyster larvae and in oyster juvenile.The breeding season of C.hongkongenis came out once in Maowei Sea during2012,and the explosive breeding season was from the early June to mid-July.The parents’ oyster gonad mature development situation of different areas were not synchronized.The gonad of breeding oyster which away from the coast was more earlier maturity. The oyster larvae developing from type D larvae to oyster post-umbo larvae needed about15-17d.June10, June30and July14were the hatching peaks of oyster larvae,whose corresponding quantity was respectively86461/m3,105330/m3and168224/m3. The quantity of oyster larvae in the spatial extent of0.5m water layer was significantly higher than that in2.0m (P≤0.01).The salinity difference of the high-tide and the low-tide was the main factor on influencing the oyster larvae quantity dynamic which was significant negative correlated to the sea area average salinity difference.According to this research, the C.hongkongensis start into the explosive breeding season in early June,when the number of oyster post-umbo larvae is up to30000/m3,we can issue the simi-artificial oyster spat collection forecast and conduct fishermen to put in the cement and oyster shell collectors for oyster spat collection during the spring tide turn to the neap tide.