摘要
采用二氨基苯基吲哚(DAPI)染色荧光显微方法,对栉孔扇贝(Chlamys farreri♀)×长牡蛎(Crassostrea gigas♂)受精过程进行详细观察。结果显示,长牡蛎精子能迅速附着并穿过栉孔扇贝卵膜,精核发生解凝缩而膨胀形成雄性原核;精子入卵后,栉孔扇贝卵子减数分裂重新启动,释放极体并形成雌性原核,最后雌、雄原核融合,受精卵开始第1次卵裂。栉孔扇贝与长牡蛎杂交受精率一般在40%左右。受精卵发育过程中出现了排放2个极体、排放1个极体、不排放极体3种类型,所占受精卵比例约为65%、25%和10%。多数受精卵第1次卵裂后期,染色体发生异常分离,不能平均分配到2个子细胞中,这可能是造成早期胚胎畸形,只能发育到担轮幼虫阶段而全部死亡的主要原因。
The fertilized eggs of crossing between Chlamys farreri （ ♀ ） and Crassostrea gigas （ ♂ ）stained with DAPI were observed under a fluorescence microscope . The chromosomal behaviors in the fertilization process were examined detailedly. The results showed that Crassostrea gigas sperms could attach to and penetrate into Chlamys farreri eggs rapidly after insemination. Then, sperm nucleus diffused and formed into male pronuclei. Chlamys farreri eggs resumed their meiosis, released polar bodies and formed female pronuclei as they were activated by the heterogenous sperms. Finally, the male and female pronuclei fused and the fertilized eggs began the first cleavage. The rate of crossing fertilization was approximate 40 %. Three types of fertilized eggs emerged during developmental process, which were two-polar-body releasing, one-polar-body releasing and none-polar-body releasing, accounting for about 65 %, 25 % and 10 % respectively. The chromosomes in majority of zygotes segregated unconventionally and could not be equally distributed into two daughter cells during the first cleavage, which might be the main reasons why the early embryos developed aberrantly and died entirely at the trochophore stage.
出处
《中国水产科学》
CAS
CSCD
北大核心
2005年第5期643-647,共5页
Journal of Fishery Sciences of China
基金
国家"863"高技术研究发展项目(2003AA603022)
关键词
栉孔扇贝
长牡蛎
远缘杂交
受精细胞学
荧光显微观察
Chlamys farreri
Crassostrea gigas
remote hybridization
fertilization cytology
observation with fluorescent microscope
