| The syrphid belongs to Aschiza, Cyclorrhapha of Diptera, Syrphidae. Syrphidae wide distribution range, except for some islands of the world Antarctica, the Pacific no local Syrphidae species recorded, the rest were all reports about the syrphid. Microsatellite DNA has the advantages of high polymorphism, abundant in the genome, and conform to the Mendelian codominant, since it was found, has always been a hot topic of biologists. Microsatellite marker technique is now widely used molecular markers, the technology maturity also allow the success rate of microsatellite marker higher.In this paper, using the method of magnetic beads enrichment efficient screening the microsatellite of Episyrphus balteatus and Metasyrphus corollae, and developing microsatellite primers. In the experiment, the Episyrphus balteatus and Metasyrphus corollae genome DNA need to be extracted firstly, then the genome DNA need to be enzyme digested, Synthetic linker was ligated with the digested fragment, then hybridization with the probe of which the 5’end labeled by the biotin. Using the combination of the bead surface of streptavidin and the biotin-binding fragment probe, and then through a series of elution method eliminate specific fragment, amplified the target fragment by PCR, then connected the product with vector and translated it into competent Escherichia coli cells by gene cloning method, so as to get a Episyrphus balteatus and Metasyrphus corollae microsatellite enrichment library. Designing the microsatellite primer by software, and selected primers with strong specificity and analysis the polymorphism of the microsatellite loci.13 microsatellite loci were screened to the Episyrphus balteatus and 48 individuals of polymorphism were analyzed, classification results showed that there was 1 loci hardly genotyped explicitly, and abandoned this loci. The remaining 12 microsatellite loci alleles for a total of 109, the average number of loci alleles of 9, the number of alleles ranged from 3 to 16. The observed heterozygosity(HO) 12 microsatellite loci in the range of 0.11 to 1.00, and the mean observed heterozygosity was 0.55..Expected heterozygosity(HE) was between 0.28 to 0.91, average observed heterozygosity was 0.69. Polymorphism information content (PIC) was between 0.09 to 0.88, the average polymorphism information content was 0.57. Only H213 PIC is less than 0.25, characterized by low polymorphism. With six loci off the Hardy-Weinberg equilibrium, the locus deviation may be null alleles exist.Metasyrphus corollae screening to 10 microsatellite loci of polymorphism analysis of 48 individuals, classification results show that there is one loci for monomorphic, and abandoned this loci. There were 9 of the polymorphism of microsatellite loci are high, the total number of alleles is 56, the average number of loci alleles is 6.27, Its locus alleles at 3 to 10. At the same time, nine loci was observed that the heterozygosity was between 0.271.00, average observed heterozygosity was 0.57. Expected heterozygosity was between 0.30 to 0.83, the average expected heterozygosity was 0.59. Polymorphism information content was between 0.27 to 0.87, the average polymorphism information content was O.53.The two loci off the Hardy Weinberg equilibrium. Episyrphus balteatus 12 microsatellite loci and Metasyrphus corollae out of nine microsatellite loci showed high polymorphism, so these loci designed for Episyrphus balteatus and Metasyrphus corollae will be use to population genetics research.Microsatellite primers has versatility in related species, we use Episyrphus balteatus microsatellite primer and Metasyrphus corollae, microsatellite primers cross amplification, primer H28、H108、DH222、DH258 had high polymorphism. These microsatellite loci offers more microsatellite molecular markers for the studies which was related species population genetic structure. |
PDF Full Text Request