Genetic Analysis Of The Products In Maize Carotenoid Biosynthesis Pathway And Maize Tassel Branch Number

In China, Maize is one of the most important crops. Increasing the maize yield and quality has a great significance to China even the world’s food supply. In this study, a natural population containing368maize inbred lines was used for association mapping to explore the relevant gene of the maize carotenoids synthetic ways. The main results of this study are as follows:1. The result of the RNA-seq result was validated in RNA and DNA level. Genomic DNA was used as the template to amplify and analysis the sequence of6hotspot genes detected by the GWAS (Genome-Wide association Study) analysis. It can be proved that the results have about90%consistency with the RNA-Seq. Also, with the sample of the grain for15days after pollination, quantitative PCR was used to detect two maize zein gene and their transcription factors, bHLH and ARID in161maize inbred lines. The correlation between the the relative expression level and the RNA-Seq results reached extremely significant level. All the results showed that RNA sequencing results have got the high quality SNP markers and gene expression data and it can be used for the further research work.2. The GWAS analysis of the content for major maize carotenoid biosynthesis products at different locations in different years shows that6genes are significant related to the corresponding traits. The correlation analysis between the content for major maize carotenoid biosynthesis products and the genes encode the enzymes in maize carotenoid biosynthesis detected that there are8genes significant correlated with some of the products. We conducted the expression quantitative trait loci(eQTL)analysis of the28key genes which encode the enzyme in the maize carotenoid biosynthesis pathway,10genes of which are cis-eQTLs and3of them are trans-eQTL.In addition, in this study, a natural population containing368maize inbred lines was used for association mapping to explore the relevant gene of maize tassel branch number. An F2:3population and high generation of backcross population of maize tassel branch number was bulid for the QTL mapping. The main results of this study are as follows:1. Totally7datasets of the tassel branch number related traits in different years and different locations were used for GWAS analysis. We totally detected25significant loci. Among that,17have been reported as the confirmed QTL so far.2. The segregated F2:3and BC3F2populations were used for QTL mapping of the tassel branch number related traits,7QTLs were detected which located on chrl, chr3, chr4, chr5, chr7and chr8respectively, and two of them detected on chr7. What is noteworthy is that the interval of M1C259223788-M1C260138854and bnlg2259-umc2197on chr7was detected both in GWAS and QTL analysis, and the effect value are relative high. The results showed that the two intervals on chromosome1and chromusome7are likely to exist the significant genes of the maize tassel branch number. This foundation It lays a solid foundation for the fine mapping and cloning of the genes of maize tassel branch number.