Fig. 1. Effect of ureide application (400 mL of 5 mM allantoic acid solution at time 0) on ARA of 5-wk-old Biloxi and Jackson soybean plants grown hydroponically on 0 µM Mn nutrition (Exp. 1). Data were double normalized, first by dividing each individual datum by the daily mean ARA of plants grown at 6.6 µM Mn and not treated by ureide, and then dividing the normalized data by the average of normalized data at 0 d. Values are the means of four replicates and bars on each point represent standard errors of the mean.