Department of Soil Science and Agricultural Chemistry, Birsa Agricultural University, Ranchi, Jharkhand, 834006.
1Present address: Department of Agronomy, Birsa Agricultural University, Ranchi, Jharkhand, 834006.
A pot experiment was conducted with twenty-eight soils with widely varying soil characters for determination of critical limit of S for green gram. Average increase in dry matter yield with S application was 65% over control. Bray's per cent yield varied from 27.8 to 61.5. In terms ofthe efficiency of extraction, the extractants found were in the order of Ca (H2PO4)2 > KH2PO4> 1N NH4OAc > Morgan's reagent> 0.15% CaCl2> 1% NaCl > Bray-1. Soil available-S extracted with 0.15% CaCl2 and Ca(H2PO4)2.H2O registered a highly significant correlation (r=0.85** and 0.95** respectively). The critical limits of extractable-S for green gram with 0.15% CaCl2 and Ca(H2PO4)2H2O were 9.5 and 33.8 mg kg−1, respectively by graphical method whereas these were 11.6 mg kg−1 with 0.15% CaCl2 by statistical procedure.
Critical limit, Bray's percent yield, chemical extractant, sulphur, green gram
