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Understanding how plants respond to drought can benefit drought resistance (DR) breeding.Using a non-destructive phenotyping facility,51 image-based traits (i-traits) for 507 rice accessions were extracted.These i-traits can be used to monitor drought responses and evaluate DR.High heritability and large variation of these traits was observed under drought stress in the natural population.A genome-wide association study (GWAS) of i-traits and traditional DR traits identified 470 association loci,some containing known DR-related genes.Of these 470 loci,443 loci (94％) were identified using i-traits,437 loci (93％) colocalized with previously reported DR-related quantitative trait loci,and 313 loci (66.6％) were reproducibly identified by GWAS in different years.Association networks,established based on GWAS results,revealed hub i-traits and hub loci.This demonstrates the feasibility and necessity of dissecting the complex DR trait into heritable and simple i-traits.As proof of principle,we illustrated the power of this integrated approach to identify previously unreported DR-related genes.OsPP15 was associated with a hub i-trait,and its role in DR was confirmed by genetic transformation experiments.Furthermore,i-traits can be used for DR linkage analyses,and 69 i-trait locus associations were identified by both GWAS and linkage analysis of a recombinant inbred line population.Finally,we confirmed the relevance of i-traits to DR in the field.Our study provides a promising novel approach for the genetic dissection and discovery of causal genes for DR.