Soybean Lutein Concentration: Impact of Crop Management and Genotypes

Lutein is a carotenoid with health‐beneficial properties found in soybean [ Glycine max (L.) Merr.]. A study was conducted in multiple environments in Quebec, Canada, to determine the effects of crop management practices and genotypes on soybean lutein concentrations. Practices evaluated included seeding rate, row spacing, seeding date, and P and K fertilization; lutein variation and stability among 20 genotypes were also studied. Management practices affected soybean lutein concentration to different degrees. Seeding date had the greatest effect on lutein concentration of all factors evaluated, but response varied greatly between environments. Differences in lutein concentration between seeding date treatments averaged 41%. Seeding rate, row spacing, and P and K fertilization effects were minimal. Increasing the seeding rate from 40 to 60 seed m −2 resulted in a 6% increase in lutein concentration. Response to row spacing and P fertilization treatment was inconsistent and differences between treatments were never >8%. There was no response to K fertilization. Large differences were observed between the 20 genotypes evaluated, with lutein concentrations ranging between 4.1 and 10.9 μg g −1 Despite the presence of significant environmental effects, genotypes with consistently high and stable lutein concentrations were identified. Selection and development of high‐lutein cultivars should be possible; however, environmental factors and crop management practices should be considered in the use of soybean as a source of lutein.