Abstract:

521 white shrimps(Exopalaemon modestus) in Taihu Lake were randomly sampled and nine morphormetric traits including abdominal length , abdominal width , body length ,carapace length，carapace width，tail length , length of upper frontal eminence , tail width and body weight were measured. The morphometric traits were used as independent variables，and body weight was used as a dependent variable .The correlation coefficients , path coefficients and decision coefficients were calculated by correlation analysis and path analysis, then effects of morphometric traits on body weight was analyzed. The results showed that path coefficients of abdominal length, body length and length of upper frontal eminence achieved significant (P<0.01 ) levels．Indirect effects of morphometric traits on body weight were higher than that of direct effect except body length . Body length, abdominal length and length of upper frontal eminence had the top three direct effect on body weight in turn. Other morphometric traits had a little effects on body weight and they mainly affected body weight indirectly through body length and abdominal length. The result of decision coefficients revealed that body length, abdominal length and length of upper frontal eminence had the most effect on body weight ,which was consistent with the results of path analysis. The morphometric traits which did not reach the significance level (P<0.05)were eliminated and others were used to establish the multiple regression equation, which was Y=-2.768+0.046X1+0.066X3+0.025X7