Effect of sulfur treatments on yield and uptake of Fe, Zn, and Mn by corn, sorghum, and soybeans

Abstract
Iron chlorosis is widespread in corn, sorghum and soybeans growing in calcareous soils in Iran. A field experiment was conducted to investigate the effect of S treatments on yield and uptake of Fe, Mn and Zn by corn, sorghum and soybeans. Elemental S (powder sulfur) was incorporated into the soil before planting with the rates of zero, 100, 200 and 400 kg/ha. Results showed that elemental S decreased the soil pH and HCC3 concentration of soil extract, and increased soil DTPA‐ extractable Fe, Mn and Zn. Iron, and Zn uptake increased while Mn uptake decreased significantly by corn, sorghum and soybeans for almost all the treatments and Iron chlorosis was corrected. Yield increase over control was significant for sorghum and soybeans for all and every treatment. For corn, however yield showed signigicant increase over control only for 200 and 400 kg elemental S/ha. The results indicated that elemental S treatment was an effective means to alleviate iron chlorosis as well as to increase yield for corn, sorghum and soybeans in calcareous soils.