Diversity Analysis Of Stem And Panicle Traits And The Construction Of Genetic Population Based On Plant Height Phenotype In Foxtail Millet

Foxtail millet(Setaria italica(L.)Beauv.)belongs to Gramineae,and its germplasm resources are very abundant.Genetic diversity analysis of phenotypic traits and the construction of genetic population of important traits are of great importance to the discovery of important genes and the selection of parents for superior hybrid.In this study,387 foxtail millet resources were selected as research materials to study the diversity of 16 agronomic traits related to stempanicle traits.Principal component analysis,correlation analysis and cluster analysis were carried out;by crossing between DTI(female parent)and male parents with different phenotypes,the F1 generation was obtained to conduct a series of morphological and molecular identifications.In addition,the genetic population based on plant height trait was initially constructed by the analysis of heterosis based on the phenotypic deteiminations of true hybrids and their parents.The main results were:1.Higher phenotypic diversity was presented on stem and spike traits of foxtail millet resources,and the coefficient variation of spike traits was bigger than that of stem traits,especially including panicle weight per main stem,grain weight per main stem and grain number of per spikelets related to yield,whose coefficient variation were more than 50%.2.The principal component analysis,correlation analysis and cluster analysis of 16 agronomic traits related to stem and spike traits were conducted and revealed that 84.167%agronomic traits were significantly correlated.These traits were divided into five categories by principal component analysis.In addition,the first principal component consisted of the middle diameter of panicle,panicle weight per main stem,grain weight per main stem and the width of spikelets,whose contribution rate was 41.184%.These foxtail millet resources were divided into three groups by cluster analysis and each group represented geographical characteristics.3.A total of 36 groups of true hybrids were identified by morphological identification of FI hybrids,and 22 groups of true hybrids were further confirmed by the molecular identification of F1 with InDel markers,Based on the analysis of the heterosis,it was found that the heterosis indexes closely related to yield were higher,such as panicle weight per main stem and grain weight per main stem.4.Through the construction of genetic population of the plant height and the phenotypic determination,it was found that the population showed an obvious separation of traits at the seedling stage,and the reliability of the genetic population was preliminarily determined.