熊本牡蛎无嵴和多嵴品系生产性状比较

Evaluation of phenotypic traits of two strains of the Kumamoto oyster(Crassostrea sikamea)

为了评估熊本牡蛎左壳放射嵴有无对其生产性能的影响,于2013年5月,以熊本牡蛎湛江群体子一代作为基础群体,筛选出无嵴及多嵴品系,采用繁殖生物学方法,比较了两个品系的表型性状差异。结果显示,野生群体中,多嵴亲本规格略大于无嵴亲本,鲜重、壳重及怀卵量均显著大于无嵴亲本;两个品系的受精孵化参数、D型幼虫大小及变态规格彼此间无显著差异;多嵴品系存活力及生长潜力在幼虫及养成期间显著高于无嵴品系。中间育成期间,湛江及大风江牡蛎养殖区环境对两品系生长性状造成了一定程度影响,表现出明显的环境效应,但是对存活力尚未造成影响。熊本牡蛎左壳放射嵴无相对于有是显性性状,主要受到一对显性基因控制,而多嵴性状是隐性性状,可以稳定遗传。研究为熊本牡蛎多嵴品系培育及其左壳放射嵴遗传机制奠定了坚实的理论基础与实践经验。

The phenotypic traits of two strains the Kumamoto oyster Crassostrea sikamea were evaluated by the reproductive biology method according to the number of radiation ribs from left shell with the Zhangjiang population as base stocks in May 2013. Results showed that the fresh weight,shell weight and fecundity of mulitradial ridge parents were significantly greater than those of non-radial ridge,while no significant difference in the egg diameter,fertilization rate,hatching rate,D larval size and metamorphic size was found between two strains.However,the survival ability and growth potential of multi-radial ridge strain were both better than those of nonradial ridge strain. Growth traits of two strains were affected by the culture conditions,while hardly any effect was observed on the viability of the environment during grow-out stage at two different sites. The radial ridge of the left shell of oyster is dominant and it is mainly controlled by a dominant gene,while the multi-ridge trait is recessive trait,which can be stably inherited. This study provided a solid theoretical foundation and practical experience for the cultivation of the multi-ridge culture and the genetic mechanism of the left shell of the oyster.