Sistim Pengairan dan Pemupukan untuk Penanggulangan Keracunan Besi dan Perbaikan Pertumbuhan Tanaman Padi pada Tanah Ultisol Morowali Sulawesi Tengah

Abstract

The Irrigation Systems and Fertilization for Preventing Iron Toxicity and Improving the Rice Growth on Ultisol in Morowali, Central Sulawesi. Newly opened lands for lowland rice are commonly less fertile complexed with iron toxicity and decreasing their productivity. The assessment was conducted to findout suitable irrigation system combined with NPK fertilizer in iron toxic condition, in order to improve the growth and yield of the lowland rice. The experiment was carried out in Une Pute Jaya Village Central Bungku District, Morowali Regency, Central Sulawesi, from September 2010 to Januari 2011. The land is acid Ultisol with iron toxicity symptoms. The experiment was designed as factorial randomized block design with two factors. The first factor consisted of tree levels of irrigation system and the second factor was four levels of NPK fertilizer combination. The results showed that site is low fertile soil with very high iron content. Submerged irrigation system beneficially influence and improve plant growth with grain yield up to 48.13 % higher than the yield obtained by the stagnant irrigation system at five cm water depth in the same fertilizer dosage (t3p1><t1p1). Moreover, submerged irrigation system could decrease iron uptake up to 82.06% and iron toxicity up to 91.06% compared to the stagnant irrigation system at five cm water depth. Reduction of fertilizer dosage up to 25% did not reduced the yield compared to the local recommended one