Genetic Linkage Map Construction And QTL Analyses Of Plant Architecture Related Traits In Lotus

Lotus(Nelumbo nucifera Gaertn.)is a kind of ornamental,edible and medicinal perennially aquatic plant,with great cultural and economic values.It is crucial for the development of lotus industry to breed new cultivars gathering multiple prominent traits.Up to now,new cultivars of lotus are always bred using traditional hyridization methods which take a lot of time,and the process is greatly limited.Moreover,it is difficult to determine the prominent genes controlling ornamaental traits.In order to detect the genetic factors of plant architecture related trait of lotus,the F1 hybrid population 'Yanyanggaozhao'×'Jianxuan-35' was chosen as the experimental materials.SSR and InDel as genetic markers and the genetic linkage map of lotus was then constructed.Hereditary variations of standing leaf height,peduncle height,leafblade length,leafblade width,flower diameter were measured and analyzed based on F1 mapping population of lotus.These QTLs for these phenotypic traits using composit interval mapping and QTLs analyses were then carried out for plant architecture related traits of lotus.The main results of this study were summarized as following:(1)the genetic linkage map with 11 linkage groups contained 145 markers,the map was 625.0cM in length with an average of 4.31 cM between adjacent marker.The number of markers on LG1 is the highest with 91 markers and 99.1cM in length.LG11 is the lowest which contains 2 markers and 33.9cM in length.(2)There were 14 QTLs for these five phenotypic traits.Proportion of phenotypic variance explain(PVE)for these QTLs was from 6.6% to 12.0%.Of these QTLs,6 QTLs were for standing leaf height accounting for the most part,4 QTLs were for flower diameter,2 QTLs for leafblade length,while only 1 QTLs was for leafblade width and peduncle height respectively.In summary,this genetic linkege map and the 14 crucial QTLs of lotus will certainly to assist in fine mapping and map-based cloning of important ornamental traits,which will also accelerate the molecular breeding of these complex traits in lotus.