Study On The Phylogeography Of Primula Merrilliana Complex

Flowers of Primula merrilliana complex are gorgeous delicate,long flowering time,with high value horticulture.However,due to factors such as human activities and fragmentation of habitats,wild resources have been drastically reduced and are now classified as rare and endangered species.In this paper,we would analyze the phylogeography of Primula merrilliana by using ribosomal gene ITS,two chloroplast gene fragments(trn L-F and trn S-G),and a single copy nuclear gene e IF3 E.The genetic diversity,genetic structure and population history of Primula merrilliana would be interpreted.The main findings are as follows:(1)Primula merrilliana has high levels of haplotype diversity and nucleotide diversity(hT>0.5 and ?>0.005),low level of total genetic diversity(HT=0.652).The gene differentiation was large(ITS: Fst=0.594;cp DNA: Fst=0.300;ITS+cp DNA: Fst=0.558;SCNGs DNA: Fst=0.240),and the gene flow was small(Nm<1).The breeding method of outcrossing and selfing,the fragmentation of habitat and the life form of biennial may be the reason for the low genetic diversity of Primula merrilliana.Analysis of chloroplast and single-copy sequences by AMOVA indicated that the genetic variation mostly resided in among populations(53.98%,56.84%).The analysis of ITS sequence showed that the variation mostly resided in among groups(72.28%).Primula merrilliana has a strong genetic structure(GST< NST,P<0.05).There is no correlation between genetic distance and geographic distance.The population has not experienced expansion.(2)The haplotypes of six populations(CG,DWD,LHT,XHY,FHS,LW)in the Qiupu River Basin were more primitive and the fourteen populations near Huangshan(BDS,DSCA,DSCB,GK,HDY,SLC,YLD,HJS,LD,QYS,WQ,YK,YT,ZS)are clearly divided into two groups.The reasons for the unclear grouping of the six populations(HTA,HTB,GCD,GCG,TJ,XD)are still unclear.(3)It is recommended that 6 populations in the Qiupup River Basin be regarded as one protection unit,6 populations with unclear grouping(HTA,etc.)as a protection unit,and 14 populations near Huangshan as a protection unit.Combined with previous studies,three populations(BDS,DSCA,DSCB)near Huangshan can be considered as an independent species for genetic protection.