Drought is a severe limiting factor for maize production in developing countries.Plants response to water stress depends on its metabolic activity.Genome-wide association studies(GWAS)are based on linkage disequilibrium(LD),representing a powerful approach in providing an opportunity to methodically analyze genetic architectures of complex traits in maize.Five thousand samples for three tissues(ear tips,silks and leaves)for two years from 318 tropical and subtropical inbred lines were collected for metabolite analysis at two developmental stages(0 days and 7 days after anthesis)under water stressed and well-watered conditions,respectively.