Development Of Novel Microsatellite Markers And Molecular Population Genetic Diversity Of Five Marine Mollusks

All along,mollusks resources are rich and succulent delicious,and usually have a higher nutritional value,occupies an important position in the marine economy.But in recent years,factors such as human overfishing and marine waters deteriorating environment or others,some species of wild resources drastically reduced,and therefore urgently needed to carry out the exploration of the genetic background knowledge of mollusks,with a view to its associated germplasm resources protection and breeding to give scientific basis.Using microsatellite molecular marker technology,this study selected with mixed biotin labeled probes?GT?₁₅5 and?CT?₁₅,constructed the microsatellite Library of Ruditapes philippinarum,Mercenaria mercenaria,Atrina vexilum Bom,Atrina pectinata and Chlorostoma argyrostoma,respectively.And then screened polymorphic microsatellite markers,in order to further analysis of the population genetic structure,germplasm identification and cross breeding to provide effective theory basis.The genetic diversity evaluation result is as follows:?1?In the R.philippinarum,10 pairs of polymorphic primers were finally screened and obtained,the number of alleles was 2-6,the polymorphism information content was 0.199-0.751,the observed and expected heterozygosity were 0.1333-0.6207 and 0.1603-0.7412,respectively.Although significant deviations from Hardy-Weinberg equilibrium were detected in locus F2-7,no significant deviations were detected in other nine loci.Results of polymorphism analysis show that the R.philippinarum populations were at the higher level of genetic diversity.?2?In the M.mercenaria,11 pairs of polymorphic primers were finally screened,the number of alleles was 2-6,the polymorphism information content was 0.059-0.498,the observed and expected heterozygosity were 0.0625-0.5333 and 0.0615-0.4977,respectively.There are 10 sites with the HWE equilibrium,locus Y1-4 deviation from HWE equilibrium,the result of polymorphism analysis showed that the genetic diversity in the low level.?3?In the A.vexilum Bom,its final selection,13 polymorphic primer pairs were obtained,and the number of alleles was 2-5,the polymorphism information content was 0.141-0.664,the observed and expected heterozygosity were 0.1250-0.6217 and 0.1223-0.6216,respectively.There are 11 sites with the HWE equilibrium,site Q2-11 and site Q2-12 deviation from HWE equilibrium,polymorphism analysis showed that the genetic diversity in the population was at the higher level.?4?In the A.pectinata,8 pairs of polymorphic primers were finally selected and obtained,the number of alleles was 2-6,the polymorphism information content was 0.233-0.447,the observed and expected heterozygosity were 0.2069-0.7931 and 0.1887-0.5124,respectively.No significant deviations were detected in all loci,the results of polymorphism analysis showed that the genetic diversity of A.pectinata is in lower level.?5?In the C.argyrostoma,9 pairs of polymorphic primers were finally selected and obtained,the number of alleles was 3-6,the polymorphism information content was 0.470-0.723,the observed and expected heterozygosity were 0.3333-0.7586 and 0.3763-0.7739,respectively.No significant deviations were detected in all loci.Results show that its genetic diversity were at the higher level.According to the results of the assessments,the genetic diversity of M.mercenaria and A.pectinata was lower,relatively,R.philippinarum,A.vexilum Bom and C.argyrostoma were all for the higher level of genetic diversity.This result shows that the M.mercenaria is the introduction of new species,wild resources of the A.Pectinata sharply reduced caused the population quantity is less.In addition,this study also proved that microsatellite marker is an effective method of convenient development of shellfish genetic markers,the data will be used for the further study in the shellfish germplasm resources evaluation,conservation genetics and artificial breeding,and indeed above results provide a scientific data effectively.