关键词: 泥东风螺, 形态, DNA条形码, 同工酶, Babylonia lutosa, morphology, DNA barcoding, isozymes

Abstract: Babylonia lutosa aquaculture scale has been expanded rapidly with the important economic value and increasing demand in recent years. It becomes more and more necessary to research and understand some information about identification, molecular markers, genetic relationship, genetic polymorphism and construction of phylogenetic tree of shellfish germplasm resources in Putian. The morphological characteristics and key measurable character indicators such as body height (H), body width (B) and body weight (W) of 39 individuals at different stages cultivated in outdoor breeding pond from Nanri Island were observed and measured in order to derive the calculation formula between these traits. The mitochondria 16S rRNA, COI as well as nuclear 18S rRNA, 18S-28S rRNA were amplificated by means of PCR and sequenced as a target gene sequence, respectively. Taking Turbo chinensis as an outgroup, the Neighbor-Joining phylogenetic trees involved in the other seven species of Babylonia or related homologous sequences of Buccinoidea were reconstructed based on the analysis and comparison of sequence similarities and genetic distances of 16S rRNA, COI, 18S rRNA, 28S rRNA, ITS1 and ITS2 genes. Also, the enzymatic activities and polymorphism of six isozymes including Esterase (EST), Malic enzyme (ME), Superoxide dismutase (SOD), Lactate dehydrogenase (LDH), Malic dehydrogenase (MDH) and Isocitrate dehydrogenase (IDH) extracted from the foot muscle tissue were analyzed by using polyacrylamide gel electrophoresis. The results showed that there was no significant difference among the individual shapes of the B. lutosa shells except for obviously irregular pattern. The average of body height (H), body width (B), body weight (W) and ratio of body height (H) to body width (B) were arranged in turn as (3.65±0.51) cm, (2.18±0.28) cm, (8.66±3.36) g and (1.67±0.06) times, respectively. While the relationship between body height and body width, body weight and body height, body weight and body width growth equations could be successively described by the power function B=0.678 2H0.901 4 (R2=0.950 2), exponential function W=0.600 5e0.713 7H (R2=0.959 3) and W=0.448 0e1.330 8B (R2=0.972 6),respectively. Topology of COI phylogenetic tree suggested that B. lutosa and B. formosae clustered together first in the genus Babylonia. And B. lutosa existed in the closest phylogenetic relationship with B. formosae simultaneously. Meanwhile, the genetic distances between B. lutosa and B. japonica, B. lani, B. areolata, B. spirata, B. habei and B. zeylanica increased gradually. All the six isozymes were found expressing in the foot tissue. EST, SOD and IDH were detected with locus polymorphism among individuals. ME, LDH and MDH showed no site polymorphism in the number of enzyme bands and merely the presence of enzyme activity difference were examined. The study will provide a valuable reference for further research of B. lutosa.