Population Differentiation Of Endangered Opisthopappus Shih In China

The genus Opisthopappus Shih,an endemic genus of China,is a perennial herb of perennial roots.Opisthopappus Shih is an important germplasm resource of Asteraceae flower breeding because of the drought resistance,shade resistance and cold resistance.Besides,they also have high ornamental value and medicinal value.The genus contains two species:Opisthopapus taihangensis?Ling?Shih and Opisthopappus longilobus Shih.These herbs only spread in Taihang Mountain,and have been nominated as the 2^nd class protection plants in China due to the reduction of its distribution range,poor reproduction ability and artificial picked it seriously.In this study,we have developed eight SNP and ten InDel maker based Transcriptome to explore the genetic differentiation,phylogeographic structure and historical distribution pattern.1.Analysis of SNP sequence.The genetic diversity of the genus Opisthopappus Shih was high?H_T=0.989,V_T=0.011,V_S=0.259?.The genetic parameters of O.longilobus were higher than that of O.taihangensis.And the genetic variation mainly existed among populations.The combined data of eighteen SNPs fragment detected a total of 51 mutation sites and 75 haplotypes.O.longilobus contained 47 haplotypes,O.taihangensis contained 28 haplotypes,and there was no shared haplotype between the two species.Analysis of haplotype network showed that haplotype H50 was widely distributed in O.taihangensis,we speculated H50 maybe the ancestral haplotype;the haplotypes of O.longilobus were more abundant and complex,and we couldn't determine the ancestral haplotype.The haplotypes differentiation time of Opisthopappus Shih appeared before 13.2 Ma.The two species haplotypes differentiation time was about 8-9 Ma before.The genus Opisthopappus Shih had not experienced an expansion during its evolution,however,both O.taihangensis and O.longilobus showed an experience of expansion?P>0.05?.Phylogenetic displayed that O.taihangensis and O.longilobus were completely divided into two branches based on combined data.But based on single-segment SNP cluster displayed O.longilobus GJT and O.taihangensis in a class,and O.taihangensis GS was mixed in the populations of O.longilobus.Gene exchange and infiltrate might occur between two species.2.Analysis of InDel markerInDel marker results showed that the Opisthopappus Shih was highly genetic diversity?PPL=93.85%,H=0.2460?,and the genetic information parameters of O.longilobus were also greater than that of O.taihangensis.AMOVA analysis showed that the population differentiation coefficient of G_STT were 0.6973.Genetic differentiation between populations was greater than that within populations.The genetic differentiation of O.longilobus was greater than that of O.taihangensis.UPGMA cluster analysis showed that 24 populations could be divided into 2 large branches.3.Meteorological Factors Impact AnalysisPrincipal component analysis showed that Annual Mean Temperature,Mean Temperature of Warmest Quarter,Annual Precipitation,Precipitation of Wettest Quarter and Altitude played a major role in the growth and distribution of Opisthopappus Shih.Nucleotide polymorphism???was significantly negatively correlated with altitude and Precipitation of Driest Month.N_a had a negative correlation with Isothermality and positive correlation with the Precipitation of Wettest Month and the Precipitation of Wettest Quarter.N_e and H were negatively correlated with elevation and positively correlated with the Precipitation of Wettest Month.PPL was negatively correlated with altitude and Min Temperature of Coldest Month,and positively correlated with the Precipitation of Wettest Month and Precipitation of Wettest Quarter.In summary,the genetic diversity of genus Opisthopappus Shih was high.the genetic diversity of O.longilobus was higher than that of O.taihangensis.Genetic differentiation mainly existed among populations.The reluctance of the monsoon season in East Asia caused by rapidly uplifting of the Tibetan Plateau during the Tertiary period and the global climate cooling during the Quaternary Period changed the living environment of Opisthopappus Shih.The conformation of canyons and rivers caused by uplifting of the Taihang Mountains and the environmental heterogeneity further strengthen differentiation.