Nodulation and dinitrogen fixation in soybean treated with sulfentrazone

Abstract

Under greenhouse conditions, the effect of sulfentrazone rates (0, 36, 72, 108 and 144 µg m^-2 of a.i.) was evaluated on growth of nodules in soybean (Glycine max(L.) Merrill cv. BR-16), inoculated with Bradyrhizobium japonicum strain SEMIA 5079, on dinitrogen fixation estimated by the content of ureides in xylem exsudate. The amino acids, nitrate and ureides contents in xylem exsudate were also determined. The number and dry matter of nodules, the content of amino acids, nitrate and ureides decreased as a function of increase of sulfentrazone rate at R₃ and R₅ development stages of soybean stages.