Correlation and Difference Analysis to Phenotype Characters for Two Kinds of Pomacea canaliculata

737 Pomacea canaliculata were collected from different places of Guangdong,among which black and yellow strains were 411 and 326 respectively.The shell width,shell length,shell height,body whorl height,body whorl width,shell mouth length,shell mouth width and live body mass were mea-sured.The correlation among the 7 traits and phenotypic differences between the two types of P.canaliculata were analyzed by SPSS 18.The results revealed that phenotype correlation coefficients among traits were significant(P<0.01).Body whorl width had a maximum impact on the body mass,followed by conch height,shell width had minimal impact to bady mass.Regression equation between mass of live body(Y) and morphological traits of shell height(X1),and shell mouth width(X2),body whorl height(X3),and body whorl width(X4),shell width(X5),shell mouth length(X6) was established using stepwise regression analysis.The equation was as follows: Y=-10.377+0.180X1-0.188X2+0.189X3+0.289X4+0.137X5-0.092X6.The yellow P.canaliculata were much bigger than the black ones in terms of shell height,shell width,shell mouth width and live body mass,but there was no significant difference in other phenotype characters.