三疣梭子蟹(Portunus trituberculatus) 4个地理群体体色差异分析

对鸭绿江口、莱州湾、海州湾、舟山4个野生群体的三疣梭子蟹(Portunus trituberculatus)头胸甲颜色进行观察及大螯斑点、头胸甲斑点、游泳足斑点数量统计,采用单因子方差分析和判别分析法对其进行比较。结果显示,4个地理群体头胸甲颜色存在显著差异,斑点数量存在显著或极显著差异;对样本所属群体进行判别分析,4个群体雌蟹的综合判别率为53.3%,其中海州湾最高,为83.3%;莱州湾最低,为30.0%;说明根据斑点数量不能精确完成个体群体归属判定。建立4个群体各自的判别函数公式,通过对同样环境下养殖的4个群体子代进行单因素方差分析,发现子代间差异减少;而家系结果显示,子代头胸甲颜色和亲本差异较大,斑点为中间型。综合以上数据初步判定,三疣梭子蟹体色受环境和遗传共同作用,且环境因素为主导因素。

Analysis of Body Color Variations Among Four Wild Populations of Portunus trituberculatus

Portunus triuberbuculatus is an important economical species in China with fast development in the past decades. In recent years, the wild stocks of P. triuberbuculatus along the coast of China have suffered from the overfishing and environmental pollution. To investigate effects of the body color diversity of P. triuberbuculatus in resource conservation, 50 individuals were collected in March 2007 from four wild geographic populations distributed in the Yalujiang Estuary, Laizhou Gulf, Zhoushan, and Haizhou Gulf. Families were established by group hybridization. Discriminant analysis and One-Way ANOVA analysis were adopted during the analytical process. Cluster analysis and discriminant analysis were conducted on spots characters of P. trituberculatus from four populations. The results indicated that the total accuracy rate of discriminant on female crabs from four gulfs was 53.3%. The lowest accuracy rate of discriminant of 30.0% was observed in Laizhou Gulf population and the highest of 83.3% was in Haizhou gulf population. Results showed that carapace color and spots were significantly different among four populations. There was a tendency for the association between less carapace color and spots with the decrease in culturing in the same environment at four populations. These results supported that body color of P. triuberbuculatus is decided mainly by environment, and that genetic also is an impact factor.