QTL Mapping and Analysis of Tiller Number in Sorghum Using High Density Genetic Map
Cao Ning
Ding Yanqing
Jiang Yuwen
Xu Jianxia
Gao Xu
Cheng Bin
Li Wenzhen
Zhang Liyi
Abstract：Tiller number(TN)is a key factor affecting plant architecture and yield in sorghum.Mapping major-effect quantitative trait loci(QTLs)controlling this trait can provide a theoretical basis for molecular ge-netic improvement of sorghum.In this study,a recombinant inbred line(RIL)population comprising 205 fam-ilies derived from the cross between the American sorghum cultivar BTx623 and the Guizhou liquor-making sorghum cultivar Hongyingzi was used as experimental material.TN phenotypes were investigated under three environmental conditions,including Guiyang in 2020 and 2021(2020GY,2021GY)and Anshun in 2020(2020AS).Based on a constructed high-density genetic linkage map,QTL mapping was performed using the inclusive composite interval mapping(ICIM)method.The results showed that a total of five TN-associated QTLs were detected on chromosomes 1,2 and 5,corresponding to five chromosomal segments.Among them,two major-effect QTLs,qTN3.2 and qTN5.1,were repeatedly identified across two environments.qTN3.2 was consistent with the known tiller number gene OsASI1,while the genomic interval harboring qTN5.1 contained a homolog of the DHT1 gene.Meanwhile,the expression patterns of these two candidate genes in various tissues at different growth stages of sorghum and the haplotype variations in 242 sorghum germplasm accessions were analyzed.The results of this study could provide a theoretical foundation for subsequent cloning and functional verification of tiller number-related genes in sorghum.
Keywords：SorghumTiller numberHigh-density genetic linkage mapQuantitative trait locus(QTL)mapping
Publication Date：2026-02-28
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：7( 34-40 )