EFFECT OF SULFUR FERTILIZATION ON NITROGEN-SULFUR RELATIONSHIPS IN ALFALFA (MEDICAGO-SATIVA-L PERS)

With increasing rates of applied S, the concentrations of total N, protein N, total S, protein S and total soluble S in the plant increased but those of the non-protein N fractions (total soluble N, amino acid N, amide N, nitrate N) decreased. An adequate supply of S in alfalfa increases a protein synthesis. S application narrowed total N:total S ratios and widened protein N:protein S ratios. One part S was required for every 11 to 12 parts of N to insure maximum production of protein.