Leaf shape and size are highly heritable in sugar beet breeding populations and may be a valuable source of diversity for improving resiliency in changing climates.

Sugar beet leaf morphology and plant architecture has largely been unselected over the past 150 years of breeding. Yet leaf characteristics and plant architecture have an impact on canopy closure and air flow, drought and cold tolerance, light capture, and ultimately sucrose accumulation in roots. Using greenhouse grown plants, we evaluated leaf morphology [e.g. color, size, shape, venation patterns] for 269 sugar beets representing 27 heterogenous accessions and 18 genetic families from the USDA ARS East Lansing sugar beet breeding program through a python-based Procrustean morphospace pipeline. Significant variability was observed within and among beet accessions and families for total leaf area, width, length, shape, and color. The greatest variability in shape was observed along the base of the leaves near the petiole attachment and the upper 1/3 of the leaf blade. Using a genome-wide association approach, SNPs associated with total leaf area and shape were identified.