The Discovery And Validation Of Functional Allelic Variation In Drought Tolerance Of Maize

Abiotic stress,such as drought,is one of the important reasons for the decrease of grain yield of maize around the world.Due to the environmental conditions,soil water holding capacity,and the plant’s sensibility to drought stress,the nature rainfall is not enough to maintain the plant growth and development,which results in reduced yields of maize.In recent years,many studies about the physiological mechanism,genetic variation and stress response of maize drought tolerance have been reported.In this study,we collected 99 drought related genes and detected SNPs of each gene by using the genome and transcriptome sequencing database,meanwhile,the function of these SNPs were further identified in a maize inbred lines panel.The results were as follows:99 drought tolerance genes were found in maize,rice,Arabidopsis and barley according to the literature.Among them,there were 53 maize drought tolerant genes,33 rice drought tolerant genes,nine Arabidopsis drought tolerant genes,and four barley drought tolerant genes.The maize homologue genesof drought tolerant genes of rice,Arabidopsis and barley were search in NCBI database.The information of all these genes were also collected,including gene position,gene length,involved pathway and so on.According to the genome and transcriptome sequencing database,19 drought tolerance genes were found in the genome database,62 drought tolerance genes were found in the transcriptome database.ZmRAV1is 1787 bp in length,locates on chromosome 3have 1 SNP.This gene was predicted to encode a transcription factor with 2 distinct DNA-binding domains,AP2 and B3.ZmRAV1 expression was upregulated in maize by dehydration,salt,and ABA stress.Use the maize inbred lineto verify the allelic variation.By MLM analysis,the results showed that have two traits were found associating with drought tolerance(p<0.05),the two traits were significantly correlated with drought tolerance was the anthesis-silking interval(ASI)and kernal number per row(KerN).