| The paper was aimed to find parents of M. japonicus with good quality. Cultivated M. japonicus' parents mostly from sea fishing groups, and overwintering cultivated have lower survival rates. The morphological quality traits between cultivated groups and wild-caught groups, and the morphological traits on body weight and meat weight was strdied by using multiple regression analysis?1? The results of difference of morphological quality traits between two groups showed that: There were 16 traits showing significant difference from 18 measured traits, wich account for 11.11%. 9 variables were attained from remove method, which all shoed significant level. The equation set by Fisher discriminant analysis from those 9 variables was 0.975C1+5.7261C2+6.402C4+0.397C5+3.202C10-0.191C11+0.076C12-79.661C16-10.949C17-22.53=0?2? The result of morphological traits on body weight and meat weight showed that: 150 Marspenaeus japonicus from wild caught group and cultivated group were separately sampled to measure 16 phenotypic traits, namely the body weight?Y1?, meat weight?Y2?, body length?X1?, carapace length?X2?, chest width?X3?, breast height?X4?, second abdominal segment length?X5?, second abdominal segment width?X6?, second abdominal segment height?X7?, telson length?X8?, telson width?X9?, telson height(X10), diameter of eye?X11?, distance of eye socket(X12), rostrum length(X13), and rostrum sawteeth numbers at superior margin?X14?. Correlation analysis, path analysis and partial regression analysis were used to study the effect of morphological traits on body weight and meat weight of Marspenaeus japonicus from this two populations. The results indicated that:?1? All the correlation coefficients between each morphological traits, body weight and meat weight were at extremely significant level?p<0.01? except X14.?2? The correlation indexes of the reserved morphological traits on body weight and meat weight in wild- caught group were 0.944 and 0.837, respectively, and the correlation indexes of the reserved morphological traits on body weight and meat weight in cultivated group were 0.955 and 0.907, respectively through the path analysis. The key variable to affect the body weight and meat weight in the cultivated group were both X1, and the important degree is in the order of X1> X2. The key variable to affect the body weight and meat weight in the wild-caught group were X1, and X2, respectively. Both of their important variables were X6.?3? Multiple regression equation used to estimate body weight, and meat weight of wild-caught populations were Y1=0.152X1+0.217X3+0.439X6+0.327X9-0.100X13-12.456, and Y2=0.129X2+0.155X3+0.17X6+0.184X11-0.078X14-4.267, respectively. Similarly, multiple regression equation used to estimate body weight, and meat weight of overwintering cultivated populations were Y1=0.180X1+0.228X2+0.129X4+0.287X6+0.330X9+0.412X10-0.371X12-20.677, and Y2=0.127X1+0.253 X6- 0.276X12- 9.972, respectively. However, the index of correlation in meat weight was only 0.837, which was apparently smaller than 0.85. Therefore the meat weight cannot be regarded as the object variable to show the difference between the cultivated group and wild-caught group. It could be regarded as good quality parent if the weight gain pattern of cultivated grupn was equal with the wild-caught group. Therefore, 0.018X1+0.228X2- 0.217X3+0.129X4-0.152X6+0.003X9+0.412 X10-0.371X12+0.100X13=8.221 should be a equation choosing parents of M. japonicus.?3? As above, It will select the parents of M. japonicas with good quality when the weight gain pattern fitting in the quality equation and morphological equation, which was 0.975C1+5.7261C2+6.402C4+0.397C5+3.202C10-0.191C11+0.076C12-79.661C16—10.949C17-22.53=0. and 0.018X1+0.228X2- 0.217X3+0.129X4-0.152X6+0.003X9+0.412 X10-0.371X12+0.100X13=8.221... |
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