Soil solarization following previous N application rates of 0, 56, 112, 168 and 224 kg·ha-1 as ammonium nitrate, and one cover crop of-sorghum-sudah (Sorghum bicolor var.) increased yields of turnip foliage (greens) by 3066 kg·ha-1 over the non-solarized treatment. Greater yield was obtained with 56 kg·ha-1 less N with solarization than non-solarization (112 vs 168 kg·ha-1). A blanket N application of 22 kg·ha-1 ameliorated the solarization effect on the 2nd harvest. Solarization had no significant effect on turnip leaf element concentration. Linear and quadratic increases in leaf N occurred as soil N increased. There was also a linear increase in tissue K and Mg due to solarization. No interactive effects were noted. Soil analysis showed salinity (EC) decreased and Ca increased with solarization. An increase in N rates decreased pH, NO3, and Mg, and increased soil salinity and NH4. Solarization had an interactive effect on soil salinity by increasing EC at 0 N and decreasing at 56 to 168 kg N·ha-1.
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