Identification of major QTL for waterlogging tolerance in maize using genome-wide association study and bulked sample analysis

In this study, nine seedling traits, plant height (PH), root length (RL), shoot dry weight (SDW), root dry weight (RDW), adventitious root number (ARN), node number of brace root (BRNN), brace root number (BRN), brace root dry weigh (BRDW), survival rate (SR), and the secondary traits that were defined as relative phenotypic value of seedling traits under waterlogging and control treatments were used in a natural population that contain 365 inbred lines to evaluate the waterlogging tolerance of tropical maize. The result showed that maize waterlogging tolerance was genetically controlled and seedling traits were significantly different between the control and waterlogging treatments. PH, RL, SDW, and RDW are important seedling traits for waterlogging tolerance identification. Some tropical maize inbred lines were identified with extreme waterlogging tolerance that can provide an important germplasm resource for breeding. Population structure analysis showed that two major phylogenetic subgroups in tropical maize could be identified. Genome-wide association study (GWAS) using 39,266 single nucleotide polymorphisms (SNPs) across the whole genome identified 49 trait-SNPs distributed on over all 10 chromosomes excluding chromosome 10. Seventy-one significant SNPs, distributed on all 10 chromosomes excluding chromosome 5, were identified by extend bulked sample analysis (Ext-BSA) based on the inbred lines with extreme phenotypes. GWAS and Ext-BSA identified the same loci on bin1.0...

Source: J Appl Genet - March 31, 2021 Category: Genetics & Stem Cells Authors: Zifeng Guo Shuangzhen Zhou Shanhong Wang Wen-Xue Li Hewei Du Yunbi Xu Source Type: research