Comparative Effect of NPK Fertilizer, Poultry Manure and Rice Mill Waste on Soil Chemical Properties, Nutrient Content and Performance of Ginger (Zingiber officinale Roscoe) in Umudike, Southeastern Nigeria

Abstract

The study examined the comparative effect of NPK fertilizer, poultry manure and rice mill waste on soil chemical properties, nutrient content and performance of ginger in 2018 and 2019 at the National Root Crops Research Institute Farm, Umudike, Southeastern Nigeria, using ginger variety (UG 1) as the test crop. There were seven treatments consisting of sole and combinations of NPK15:15:15, poultry manure and rice mill waste with a rate of 45 kg N/ha regarded as a full dose. They were arranged in RCBD with three replications. Results showed that the application of the amendments significantly (p<0.05) increased soil chemical properties with the combined application of NPK and poultry manure, giving the highest value for most of the parameters determined. The NPK and poultry manure significantly reduced soil acidity from a very strong acidic level of 4.80 and 4.90 (initial values before the experiment) to 5.30 each year. It increased available phosphorus from 18.50 mg/kg to 23.50 mg/kg and exchangeable calcium from 3.60 cmol/kg to 4.40 cmol/kg in 2018 and it increased total nitrogen from 0.98 g/kg to 1.30 g/kg and exchangeable calcium from 3.20 cmol/kg to 4.00 cmol/kg in 2019. The combined treatment of NPK and poultry manure equally gave the highest nutrient content for both planting seasons; (N: 0.38%, P: 0.78%, K: 0.32%, Ca: 0.44% and Mg: 0.24%) in 2018 and (N: 0.34%, K: 0.31%, Ca: 0.31% and Mg: 0.19%) in 2019, except in the phosphorus content in 2019 was plot treated with the sole treatment of NPK gave the highest nutrient content of 0.72% and was significantly (p<0.05) higher than other treatments. The growth parameters were highest in the plot treated with NPK and poultry manure for both seasons. The highest yield of 49.6 t/ha and 51.0 t/ha were obtained from NPK and poultry manure in 2018 and 2019, respectively. Therefore, it can be concluded that the combination of NPK fertilizer and poultry manure is a promising amendment for increasing soil chemical properties, nutrient content, growth parameters and yield of ginger in Umudike.