Figure 1.

Reduced power to identify causal loci in phenotypically constrained populations. A, A genome-wide association analyses for plant height, defined as the distance between the soil surface and the top of the panicle at maturity, using field collected data for 357 lines from SAP and the set of genotype call data used in this study. The location of Dw1, Dw2, and Ma1 are indicated with dashed lines, as is an additional known height locus (KHL) identified in multiple prior GWAS conducted on height in this population using different genetic marker data. B, Distribution of observed heights for the 357 lines employed for association analysis in A. The set of 38 lines above 2 m in height are marked in red. C, A genome-wide association analysis identical to that shown in A but with the exclusion of lines with the field heights >2 m (38 lines) and those which we were not able to successfully germinate and phenotype in this study (27 lines).