Fig. 1

Phenotypic responses to heat stress within a maize diversity panel. a Genotypic variants segregated 102 genotypes (including 5 flint/popcorn, 9 iodent, 9 mixed, 32 non-stiff stalk, 20 stiff stalk, 3 tropical, and 24 unknown) employed in this study using principal component analysis. b Plants showed a distinct pattern using two photosynthetic parameters—Y(NO) and Y(II)—measured under control and heat conditions. c Associated loci were detected under control and heat conditions using GWAS for Y(NPQ). Two thresholds including 2.2e⁻⁶ (blue) and 1.1e⁻⁷ (red) were applied for detecting significantly associated loci; d Same as c for Y(NO); e Same as c for Y(II)