Soybean Cultivation Technology Package on Tidal Swamp Lands in Indonesia

The main constraints of the tidal swamp lands in Indonesia for soybean growth are low soil pH, high Al saturation, and low nutrient availability of N, P, K, Ca, and Mg. The objectives of this research were to determine tolerance of several soybean varieties to Al saturation level, and to obtain a technological package for soybean cultivation which was suitable for farmers to adopt on tidal swamp lands. The research consisted of two stages of study. The first stage formulated of technology package, and the second stage evaluated feasibility of the technology package which was formulation from the first stage. The first stage studied the effect of dolomite application (20%

- 30% of soil Al saturation) on four soybean varieties (Anjasmoro, Panderman, Dega 1, and Demas). The second stage studied the effect of three technological packages: existing technology; water- saturated soybean cultivation (WSC); and alternative technology which was formulated from the results of the first study. In the 30% of soil Al saturation condition, the alternative technology package (application of 50 kg urea + 75 kg SP36 + 50 kg KCl + 1500 kg organic fertilizers/ha + rhizobium biofertilizer “Agriosy” 0.25 kg/50 g seeds/ha) gave soybean yield of 1.78 - 2.72 t/ha for all

of soybean varieties tested. The alternative technology package with Anjasmoro variety provided higher seed yields (2.62 t/ha) compared to the existing technology (2.07 t/ha) and WSC technology package (2.44 t/ha). The alternative technology package gave a profit of 11,595,000 IRD/ha with B/C values of 1.71 which was higer than the existing and WSC technology packages. The alternative technology package was more profitable than the existing technology (current farmer practice) and water-saturated soybean cultivation technology packages.