关键词: 砂海螂, 表型性状, 重量性状, 通径分析, 决定系数

Abstract:

Fifty individuals were randomly selected from the four instar in the wild populations of Mya arenaria Dalian Lushun Longwangtang waters. And then, the measurement of shell length (X1), shell height (X2), shell width (X3) and weight (Y1), the shape of live weight and soft body weight (Y2) were performed, while correlation coefficient between characters was also calculated. The effects of phenotypic traits on weight traits were analyzed by means of correlation and path analysis. The results showed that the correlation between the 5 quantitative traits reached significant level (P<0.05). The correlation coefficient is from 0.676 to 0.931. Phenotypic traits had the same effect on live weight and soft body weight. The largest of the two direct effects are shell length, while their values were 31.80% and 23.90%, respectively. The largest indirect effects of the two are shell width, while their values were 10.80% and 8.40%, respectively, and shell height is the least. Multiple regression analysis was established for the regression equations of shell length (x1), shell height (x2), shell width (x3) with 3 estimates of live weight (Y1) and soft body weight (Y2) as: Y1 = 1.421X1 + 1.563X2 + 0.722X3 -125.360 and Y2 = 0.348X1 + 0.390X2 + 0.169X3 - 28.119. The results for Mya arenaria provided a theoretical basis for selective breeding: in order to improve the living weight or soft body weight, the shell length was the main consideration, while strengthen the coordination of shell width should be also considered.

Key words: Mya arenaria, Phenotypic traits, weight traits, path analysis, determination coefficient