Performance, Nutrient Uptake and Profitability of Amaranthus Cruentus (Linn.) in Response to Different Soil Amendments

Abstract

Studies was conducted at the Teaching and Research Farms of Benson Idahosa University, Benin City, Nigeria in 2009 and 2010 to evaluate the effects of different soil amendment materials on some soil properties and performance in terms of nutrient content, uptake and proximate analysis of Amaranthus cruentus. The experiment, which was organized in a randomized complete block design, had three replications with control, organic fertilizer in two levels (20 and 40 t ha-1), inorganic fertilizer (NPK) and combined inorganic and organic fertilizer (organomineral fertilizer) at acombination of 20 t ha-1 organic fertilizer and 100 kg ha-1 NPK. Results showed that soil pH, organic carbon, total N, available P, exchangeable Ca, Mg and K were increased in through the incorporation of organic and organomineral fertilizers. However, soil pH and organic carbon contentwere reduced in NPK treated plots. Stem girth and plant height was highest with 40 t ha-1 organic fertilizer treatment at four weeks after transplanting. Mean leaf number, leaf area index (LAI) and total dry weight (TDW) followed similar pattern throughout the sampling periods. Fresh herbageyield was significantly influenced by soil amendments and the highest herbage yield (10.60 t ha-1) was obtained from 40 t ha-1 treatment. The NPK treatment produced the yield with the maximum nutrient content and uptake. The organomineral fertilizer treatment was the most expensive but the optimum yield was produced by 40 t ha-1 organic fertilizer treatment based on revenue (N530,000), gross margin (N439798.10), Net profit (N421675.39) and benefit-cost ratio (4.20) the among thetreatments.