| Corn,as an important food,feed,and energy crop,plays an important role in ensuring national food security.Yield is the primary goal of maize production,influenced by yield per plant and planting density.As an important component of yield per plant,ear traits have advantages such as high heritability and low environmental impact compared to yield per plant.Therefore,identifying QTLs related to controlling maize ear traits and analyzing candidate genes is of great significance for analyzing the genetic basis of maize yield and creating high-yield advantageous germplasm.In this study,one F2:3population containing 131 families derived from ZNC442 intercrossed with SCML0849,was treated to be materials.The F2population was genotyped by using genome by sequencing（GBS）technology,and combined with the phenotypic evaluation of the ear length,ear diameter,ear row number and kernel number per row of the population under two different environments,And QTL mapping were done by using inclusive composite interval model of ICIM software.On this basis,Combining the Transcriptome data of inbred line Mo17 and inbred line B73,consistency analysis and bioinformatics analysis were conducted to screen the key QTLs and related candidate genes that control ear traits.The results are as follows:1.Phenotypic analysis showed that there were significant differences in ear traits between parents and their families in the two environments,and the coefficient of variation among families was in the range of 8.06～17.39,showing continuous changes and conforming to the quasi-normal distribution.Based on GBS technology,a total of 31146 high-quality SNP markers were obtained,with a physical map length of 2104.07 Mb and an average spacing between markers of 67.56 Kb2.A total of 47 QTLs controlling ear traits were detected in the positioning results,including 12,7,22 and 6 QTLs controlling ear length,ear diameter,ear row number and kernel number per row,respectively,and 6 major QTLs,which explained the total phenotypic variation within 2.44%～12.85%.Compared with previous reports,this study identified a total of 25 consistent QTLs that control ear related traits.3.Transcriptome results showed that there were 4469 differentially expressed genes between B73 and Mo17,including 2567 upregulated expression of genes and 2102downregulated expression genes,which were respectively involved in plant hormone signal transduction,MAPK signaling pathway,phenylpropane biosynthesis and other pathways.There were 45 up-regulated and down-regulated differentially expressed genes overlapping QTL sections.4.Based on the results of public data analysis,a total of four candidate genes affecting ear traits were predicted,namely Zm00001d031620,Zm00001d028217,Zm00001d024523 and Zm00001d036917.By analyzing the four candidate genes combined with the Transcriptome expression data,it was found that only Zm00001d024523 was differentially expressed in B73 and Mo17,which may have a negative regulation effect on the ear row number. |
