红壳色文蛤选育子代各壳色的形态分化及养殖效果的比较

Morphological diversions in the color of Meretrix meretrix offspring and comparison of breeding effects

以红壳色为目标性状,于2009年进行了文蛤(Meretrix meretrix)的群体选育研究,建立了红壳色选系子一代(Fl),对子一代壳色种类、分布频率及其数量性状进行了统计、测量和分析,并对各壳色的形态、生长速度做了研究.结果表明,文蛤壳色具有多态性,红色、黄色、白双、黄双、波纹的分布频率分别为75.58%、8.55%、0.53%、14.83%、0.50%.红壳色亲本的子代中出现红色∶花色=3∶1,符合孟德尔遗传模式.聚类分析与欧氏距离矩阵结果表明,文蛤波纹与黄色遗传距离最近,白双与黄双遗传距离相近,与红壳色的遗传距离最远.主成分分析显示白双文蛤与黄双文蛤在空间分布上相对重叠,波纹文蛤与黄色文蛤具有较高的重叠率,而红壳色文蛤相对分散,从而进一步说明5种壳色文蛤的遗传距离关系.经过1a同池养殖,子代壳长多数已达到10～30 mm,红壳色文蛤的日生长率为0.20%,花壳色文蛤的日生长率为0.18%,且红壳色文蛤的相对比较生长速度比花壳色文蛤快10.41%.红壳色文蛤选育子代的壳长与壳宽、壳高、粒重存在一定的回归关系.红壳色文蛤壳长对壳宽、壳高、粒重的回归方程分别为:y1=0.502 4x1-0.556 0(R2=0.992 0)、y3=0.8103x3+0.620 0(R2=0.995 6)、y5=0.000 3x25.9029(R2=0.991 9),花壳色文蛤壳长对壳宽、壳高、粒重的回归方程分别为:y2=0.495 3x2-0.419 2(R2=0.990 9)、y4=0.798 5x4+0.793 5(R2=0.995 6)、y6=0.000 4x26.845 8(R2=0.993 4).研究结果为文蛤的红壳色定向选育奠定了理论基础.

Aimed at the red shell color,Meretrix meretrix was studied on the basis of mass selection in 2009.Relationships among shell colors and quantitative traits of the shells,types of shell color and their distribution frequency were quantified besides shell length,shell width,shell height,morphologies and growth rate.The results showed that the frequency of shell colors in red,yellow,double-white,double-yellow and ripple were 75.58%,8.55%,0.53%,14.83% and 0.50%,which indicated that the colors of shells was of polymorphism.The shell color of the offspring from parents with red color were consistent with the expected ratio（3∶ 1）according to Mendel′s law.The cluster analysis and Euclidian matrix show that the ripple shell was the most closest to the yellow shell,double-white was closer to the double-yellow,and the furthest was between red and other colors.Results of principle component analysis revealed that the spatial distribution of different shell colors could further explain the relations among 5 color shells.In the same pond,shell length of offspring mostly reached 10～30 mm after one year.The daily growth rate of red shells was 0.20% while the rate of other color shells was 0.18%.The growth rate of red color shells was 10.41% higher than other color shells.The shell length regressed well with shell width,shell height and individual weight.The regressions of length to the width,height and weight can be expressed as y1=0.502 4x1-0.556 0（R2=0.992 0）,y3=0.810 3x3＋0.620 0（R2=0.995 6） and y5=0.000 3x2.902 95（R2=0.991 9）,respectively.The regression equations of other color shells were y2=0.495 3x2-0.419 2（R2=0.990 9）,y4=0.798 5x4＋0.793 5（R2=0.995 6） and y6=0.000 4x2.845 86（R2=0.993 4）,respectively.The results provide a theoretical support for the breeding of red color shells of M.meretrix.