Investigation Of Wild Parent Of Chinese Old Garden Roses Based On SSR Molecular Markers

Rosa is a Rosaceae plant,which has rich phenotypic diversity and great value in science,ornamental and medicinal aspects.Rosa is also loved by people for its beautiful cultural connotation and has important cultural value.Chinese old garden roses have contributed key biological and important ornamental traits such as continuous flowering and double flower to modern roses.However,it is not clarify which wild species resources participated in the formation of Chinese old garden roses.For this reason,we conducted the following research:Using 14 pairs of SSR molecular markers with rich polymorphism,good repeatability and high amplification efficiency,which are evenly distributed on 7 chromosomes of Rosa,the genetic relationship and population structure of 191 Rosa materials were analyzed,focusing on the wild parent of Chinese old garden roses,providing more genetic background information for the study of the origin and domestication mechanism of Chinese old garden roses and modern rose,and also providing theoretical basis for rose the critical trait gene resources excavation and breeding.The main research results are as follows:1.Genetic diversity analysis of 191 materials from 4 groups of Rosa showed that the wild species group had the highest genetic diversity,the other groups were lower,and the lowest was the modern rose group.In addition,the genetic diversity of Chinese old garden roses groups is significantly lower than wild species groups.It can be seen that a large amount of genetic material may be lost during domestication of Rosa,and the genetic basis gradually narrows.2.We analyze the molecular variation of 191 samples of Rosa,found that 85%of the genetic variation comes from within groups,and only 15%comes from among roups.In addition,among the 74 materials of wild species and Chinese old garden roses,87.82%of the genetic variation existed within groups,and 12.18%of the genetic variation existed among groups.It is indicated that the genetic variation of Rosa plants mainly comes from individuals within the group.3.Neighbor-joining(NJ)clustering and principle coordinate analysis(PCA)showed that R chinensis var.spontanea,R odorata var.gigantea,R odorata,R odorata var erubescens,R odorata ’Light Pink’,R odorata’Single Pink Blush’,R laevigata are closely related to Chinese old garden roses such as R.chinensis’Old Blush’,R chinensis’Viridiflora’,R chinensis’Yueyuehong’,while R odorata’Light Pink’ is closely related to R ’Yulinglong’.In addition,the population Structure analysis software structure is used to analyze the population structure of wild species and Chinese old garden roses,when the optimal subgcroup number K=2,the two groups of wild species and Chinese old garden roses are divided into two subgroups,R chinensis var.spontanea,R odorata var.erubescens.,R odorata ’Light Pink’,R Indica,R odorata’Double Light Yellow’,R odorata ’Buddha’s Smile,5 R odorata var.pseudindica,R odorata’Xiangyun Light Yellow’,R odorata’Purplish Blush’,R multiflora var.cathayensis and Chinese old garden roses share the same genetic background,that is,these wild species and Chinese old garden roses have the closest genetic structure and are likely to contribute the most to the formation of Chinese old garden roses.R multiflora inermis,R rubus,R luciae,R lichiangensis,R laevigata,R odorata var.gigantea,R odorata,R odorata’Single Pink Blush’,R odorata’Foribunda’and Chinese old garden roses share a certain proportion of genetic background,these wild species may also have contributed some genetic resources to the formation of Chinese old garden roses.4.Analysis of the genetic relationship of modern rose shows that the modern rose group first gathers together with the Chinese old garden roses varieties such as R’Yijifen’,R’Yushizhuang’,R ’Guoguofuren’,R’Junang",R ’Jinfenlian’,R’Yingrihehua’,R ’Ruanxianghong’,and then with the Chinese old garden roses varieties such as R chinensis ’Yueyuehong’,R chinensis’Old Blush’,R chinensis’Viridiflora’,R chinensis ’Ziyuejihua’,and two wild species such as R macrophylla and R odorata var.erubescen.It can be seen that the Chinese old garden roses and a few Rosa wild species may be participated in the formation process of the modern rose.In addition,in obvious contrast with wild species,the genetic background of modern rose is very narrow,and a large number of Rosa resources are not involved in the breeding of modern roses.5.Analysis of the genetic relationship of Yunnan folk cultivated rose shows that R’Pingyin’,R ’Kushui’,R ’Siji’,R ’Shaxidiantou 5’,R ’Jinbian’,R ’Tuwei’,R’Muxiang’ and other varieties are gathered together with wild species.R’Bangladesh’,R’Shaxixiangtouhuang’,R’Shaxidiantou 9’,R ’Heqingbinguan’,R’Dianhong’ are gathered together with Chinese old garden roses.R’Shaxidiantou 2’,R’Shaxidiantou 8’,R’Heqing 1’,R’Heqing2’,R ’Eryuandapeng’,R’Zihe’,R’Crimson Glory’ and modem roses are gathered together.The above results indicates that Yunnan folk cultivated rose groups include wild species,Chinese old garden roses and modern rose,which contain rich Rosa germplasm resources.