Leaf and Seed Micronutrient Accumulation in Soybean Cultivars in Response to Integrated Organic and Chemical Fertilizers Application

Plant nutrients can be influenced by organic materials of soils. An experiment was conducted to evaluate the effect of organic amendments on elements uptake by soybean cultivars in a silty loam soil in Mazandaran province, Iran. The experiment was carried out in split plot based on randomized complete block design with three replications in 2006. Main plots were included 8 fertilizer treatments consisted of 20 and 40 Mg ha-1 Municipal Solid Waste Compost (MSW), Vermicompost (VC) and Sewage Sludge (SS) which enriched with 50% chemical fertilizers needed by soil, only chemical fertilizer treatment and control. Sub plots consisted of three genotypes of soybean (032, 033 and JK). Grain yield was determined and soybean leaves and seeds were digested and analyzed for Mn, Cu, Zn and Fe. Results showed that yield and elements content in soybean leaves and seeds (Mn, Cu, Zn and Fe) were influenced by all treatments. The 40 Mg ha-1 of sewage sludge enriched with chemical fertilizers produced maximum grain yield. Different soybean cultivars had also significant differences in terms of leaf and seed micronutrients accumulation. Maximum grain yield was observed in JK and 033. Mean comparisons showed that interaction effects of fertilizer and cultivar had significant differences on Mn, Cu and Fe content in soybean leaves, so that the maximum Cu content was observed in 032 cultivars with 40 Mg ha-1 enriched sewage sludge and municipal waste compost. Also the highest amount of Fe was obtained for JK cultivar when the 40 Mg ha-1 of municipal compost was used. Among different mentioned traits, Fe and Cu content in leaf and seed and Zn content in leaf had a positive and significant correlation with grain yield.