Genome-wide Association Analysis Of Salt Resistance Genes In Maize Seedling

In the world,maize is an important food crop and cash crop,its planting area and yield are increasing year by year.As time goes by,the salinization of cultivated land around the world restricts the production of salt-sensitive crops,so it is an urgent need for maize production development to improve its tolerance to salt stress.Genome-wide association analysis is an important research method to analyze the genetic basis of salt stress tolerance in maize.Compared with linkage mapping,it has high accuracy,short research time,and can obtain multiple candidate genes related to target traits.CRISPR/Cas9 gene editing technology has been widely used in the study of plant gene function,providing a powerful tool for the genetic improvement of important traits in crops.This study by means of paper roll hydroponic maize natural salt processing for phenotypic variation group data,through a genome-wide association analysis method of mining of candidate genes related to salt stress,using the CRISPR/Cas9 gene editing techniques have the function of the candidate genes deletion mutants,to explore the key genes and their molecular mechanism of corn in response to salt stress,improved maize salt resistance gene resource and theoretical basis.The main research results are as follows:?1?With the method of paper coil hydroponics,the treatment concentration of 150 mM NaCl was selected,and 250 representative natural variation populations of maize were treated with salt to obtain 103 reliable phenotypic data.Phenotypic data included corn,and dry weight,shoot height,lateral root number,mesocotyl and root length.?2?Genotype data were correlated with phenotypic data by using genome-wide association analysis to identify candidate genes.A total of 131 candidate genes were obtained,including 24 candidate genes related to dry weight,75 candidate genes related to shoot height,10 candidate genes related to mesocotyl,20 candidate genes related to lateral root number and29 candidate genes related to root length.According to gene function annotation and biological research reports of homologous genes in arabidopsis thaliana,6 candidate genes related to salt stress were finally identified,which were genes GRMZM2G356260?GRMZM2G110735?GRMZM2G071630?GRMZM2G109527?GRMZM2G154628 and GRMZM5G871347.?3?Construction of six maize candidate gene overexpression vector,T₀ generation transgenic plants were obtained by using the genetic transformation technology of setaria.?4?Using the CRISPR/Cas9 gene editing technology,gene editing was carried out on the homologous genes corresponding to 6 candidate genes of maize salt stress in the setaria,and the T₀ generation gene function deletion mutant plants were obtained.