Population structure and linkage disequilibrium of sesame. (a) Structure analysis of 29 sesame strains based on whole-genome sequencing. (b) LD decay determined using squared correlations of allele frequencies (r2) against distance in sesame. (c) LD of sesame, shown using a slide window of 100 kb. Red and white spots indicate strong (r2 = 1) and weak (r2 = 0) LD, respectively.