Population Genetic Structure And Diffierentiation Of Lycorma Delicatula Based On Microsatellite And Mitochondrial Gene Markers

Lycorma delicatula(White,1845)(Hemiptera: Fulgoridae)is serious phytophagous pest,mainly distribute in southeast Asia,this pest may damage more than 70 agricultural and forest plants,including grape,kiwi fruit and ailanthus,usually bring about significant economic losses.However,the population genetic structure and diffierentiation remain poorly studied so far.In this study,9 polymorphic microsatellite loci were selected and combine two mitochondrial markers,the population genetic structure and diffierentiation of Lycorma delicatula were deeply investigated.The main results are as follows:1 、 Screening of microsatellite sites: the amplification stability of twenty-three microsatellite sites of Lycorma delicatula from Chinese populations was studied by PCR method.The results show that some locus cannot be expanded stably in eight Lycorma delicatula populations,including LD-D2、LD-D3、LD-T1、LD-T2、LD-T3、Lde02、Lde10、Lde12、Lde14,but locus including LD-D1、LD-D4、LD-D5、Lde01、Lde03、Lde04、Lde05、Lde06、Lde07、Lde08、Lde09、Lde11、Lde13、Lde15 can.2、Polymorphism of microsatellite sites: the frequency of null alleles of fourteen microsatellite loci ranged from 0.000 to 0.183,the polymorphism information content ranged from 0.314 to 0.798,the allele abundance ranged from 3.09 to 15.82,observed heterozygosity ranged from 0.416 to 0.745,expected heterozygosity ranged from 0.385 to 0.837,and the mean number of alleles of eight population fourteen locus ranged from 2.75 to 13.75.Because of the average allele is less than 4 in Lde01、Lde03、Lde06、Lde09、Lde13,therefore,these locus are not used in the study.3、Genetic structure and differentiation of different geographical populations: structure cluster analysis show that these 8 geographical populations of Lycorma delicatula divided into 2 groups.The group one Shandong、Beijing、Henan and Anhui populations,the group two consist of Shanxi、Gansu、Zhejiang and Fujian populations.AMOVA analysis indicate that most of the genetic variations occur within a population,and a small part occur from groups and populations.4、Sequence variation analysis of mitochondrial gene ND2 and ND6: one hundred and eighty-two individuals from 8 Chinese populations were amplified and sequenced by two mitochondrial genes(ND2,ND6),in which ND2 is 552 bp in length and containe 19 variable sites,12 of them were parsimony information sites,7 of them were singleton sites.ND6 is337 bp in length and containe 10 variable sites,4 of which were parsimony information sites and 6 were singleton sites.No insertion or deletion were found in all sequences.The proportion of variable sites were 3.4%(ND2)and 3.0%(ND6),respectively.Additionally,two genes displayed base bias which A+T contents were considerably higher than G+C contents.5、Genetic diversity analysis of mitochondrial gene ND2 and ND6: There were 27 haplotypes of two mitochondrial genes in 8 populations,including 16 and 11 haplotypes in the mt DNA ND2 and ND6,respectively,3 haplotypes in ND2 were shared in all populations and2 haplotypes were shared in ND6.Haplotype H1 in ND2 gene contained 80 individuals of 5populations,H6 in ND2 hold 33 individuals of 2 populations,H10 in ND2 hold 38 individuals of 2 populations.Haplotype H1 in ND6 containe 134 individuals of 6 populations,while H2 in ND6 had 33 individuals of 2 populations.