Organically production of soybean supported by fertilizers residue under saturated soil culture

Abstract

Organic farming system can use natural on-farm inputs that are normally available at the production site. Saturated Soil Culture (SSC) is a technology in cultivation that gives water permanently, maintains and keeps its depth constantly; this makes soil layer in saturated condition. SSC technology can be implemented in land with poor drainage or in cultivating soybean on rice field in the period between two rice plantings when the soils may still be in water saturated conditions. The experiment was conducted to study the response of two soybean varieties to the residues of different types of fertilizer in an organic farming system. The experiment was carried out at IPB experimental station, Bogor, Indonesia, in October 2010-February 2011. Split plot design was used with types of fertilizer as the main plot (chicken manure, Centrosema pubescens Benth, and Tithonia diversifolia Hemsl.) and soybean varieties as the sub plot (Anjasmoro and Wilis). To study the effectiveness of fertilizers residue, the current experiment applied 50% fertilizer rates (10 t chicken manure only/ha, 5 t chicken manure mixed with 2.1 t C. pubescens/ha, and 5 t chicken manure with 2.1 t T. diversifolia/ha) of those applied in the previous soybean planting (May-August 2010). The results showed that chicken manure yielded the highest seed weight and filled pod number per plant. However, seed yields per hectare were not affected by fertilizer types. The soybean plant with the application of chicken manure, C. pubescens, and T. diversifolia produced 2.37, 2.42, and 2.43 t seed/ha, respectively. Wilis had higher number of filled pod per plant than Anjasmoro, but the yields per hectare of both varieties were not different. Production of Anjasmoro and Wilis was 2.43 and 2.38 t/ha, respectively.