The observation results of the tolerance test of clam seedlings (19.56±1.28 mm,2.12±0.38 g) with salinity of 0, 2, 4, 6, 8, 10, 30 psu. 3 Observation results of tolerance test. In the 35℃ group, the 24-hour survival rate was 100%, and the 48-hour survival rate was above 80%. At 72 hours, 0, 4, and 6 psu. only remained
below 70%, and 30psu., 10psu., and 8psu. were still more than 90%. Survive. After 96 hours, below 10 psu. are all below 40%, and 10 psu is still 66.7±15.2%. In the 37°C group, the 24-hour survival rate was 100%. At 48 hours, there was still 80% survival rate under 10 psu except for the 2 psu group, and both were less than 60%. There was no alive at 0, 2, 4, 6, and 8 in 72 hours, with 30 psu. (76 ± 6%) being the best, followed by 10 psu. (63 ± 15%). It shows that the tolerance to salinity of clams increases with temperature, and the tolerance of clams in lowsalinity environment decreases.
In the study, high quality genomic DNA was extracted from the gill tissues of hard clams individual collected from New Taipei Tamsui, Mazu islands, Changhua, Yunlin and Tainan, using a new genomic DNA extraction according to the CTAB DNA extraction method.Previous studies of hrad clams were mostly focused on morphology, artificial breeding, and environment factors. Studies of the population structure of this economically valuable species remain insufficient, so sutdies on the develpoment of genetic markers are urgently needed. In this study, five novel SCAR markers of hard clam was developed, which may be useful for future studies associated with population genetics and the protection of species resources. After inspecting 50 sets of amplified bands of RAPD primers, we selected 5 of them for subsequent analysis as follow analysis. These 5 sets of primers could amplify a total of 82 bands, of which 37 polymorphic bands can be analyzed between 100 basepair to 1000 basepairs. Using UPGMA (Unweighted Pair Group Method with Arithmetic Mean) for cluster analysis can divide 248 individuals into six groups as the genetic similarity was 0.44, we can clear separate the wild clams and cultured clams efficiently.