Analysis Of The Pedigree And Genetic Structure Of Sweet Potato In China Based On Whole Genome Variatio

Sweet potato(Ipomoea batatas(L.)Lam)is an important food and grain-forage crop that is widely cultivated in the world.China is the largest producer of sweet potato,and a large number of varieties have been cultivated and promoted through hybrid and other breeding approaches.With the increasing number of germplasm resources,understanding the pedigree relationship and genetic structure among the existing sweet potato varieties can provide better protection and efficient use of the available sweet potato materials.This study conducted a statistical analysis on the information of pedigree information of more than 700 sweet potato varieties which reviewed(recognized)in China before 1980 and since 1985 of pedigree information,and displayed the genetic pedigree structure of existing cultivated varieties in the form of network genetic pedigree map visually and clearly,and the main breeding methods and parental materials were analyzed and evaluated to provide fundamental data for sweet potato breeding in China.In recent years,despite evolving sequencing technologies,the genetic studies of sweet potato are far behind other major food crops due to its highly heterozygous hexaploid genome(2n=6x=90).In this study,combined with the pedigree information collected,the whole genome resequencing of 107 sweet potato germplasm materials in the network genetic pedigree map was conducted.In total,13,921,653 high-quality single nucleotide polymorphisms(SNPs)were identified by genotyping,providing an important genomic resource for sweet potato in China.Based on SNPs,the genetic structure analysis of Chinese sweet potato was conducted,and divided the accessions into four groups.The group evolution analysis was combined with pedigree information and the following conclusions are obtained Group 4(purple)is the initial group of sweet potato varieties,and the sweet potato material in group 2(blue)may represent the unique gene pool of sweet potato in China.Phylogenetic analysis,Principal component analysis(PCA)and population structure analysis were well validated.Our results support that Chinese sweet potato varieties have high genetic diversity,but the differentiation between the groups is very small,and the kinship coefficient between varieties showed small differences between varieties.Combining genomic information and pedigree information,pedigree identification and inference of parents can further complement the network genetic pedigree map,providing some reference and basis for parent selection in subsequent sweet potato breeding.