Effects of Organic And Inorganic Manures on The Yield Of Yam Tubers In Termite Infested Soils

Abstract

A study on the effects of different organic and inorganic manures on the yield of yam tubers in termite infested soil of Owerri Imo State, South Eastern Nigeria was carried out at the Teaching and Research Farm of the Federal University of Technology, Owerri in 2004 and 2005 cropping seasons respectively. The soil was naturally infested with three types of termite genera, namely: Microtermes, Ancistrotermes and Macrotermes. The variety of yam used was Dioscorea rotundata (white yam) cultivar (cv.) Obioaturugo, planted in May 2004 and 2005 respectively. The experiments were laid out in a randomized complete block design (RCBD) with three replications. The treatments were poultry manure at 1.5 tons ha-1 (PMI) and at 3.0 tons ha -1 (PM2), pig slurry at 1.5 tons ha-1 (PS1) and at 3.0 tons ha-1 (PS2), municipal waste at 1.5 tons ha-1 (MW1) and at 3.0 tons ha-1 (MW2), NPK 15:15:15, NPKMg 12:12:17:2, NPK 20:10:10 each at 400kgha-1 and control (no manuring). Result showed that highest fresh tuber yield was recorded in plots where NPK 15:15:15 and NPK Mg 12:12:17:12 were applied in both years while the least was in control plots. Also in both years of the experiment, plots treated with organic manures generally gave lower fresh tuber yield than inorganic but showed marked reduction in termite damage especially with municipal wastes when compared with other treatments. Similarly, plots treated with organic manures gave higher soil pH after tuber harvest than inorganic manures.

Keywords: inorganic manure, organic manure, termites, and tuber yield.

International Journal of Agriculture and Development Vol. 9 2007: pp. 66-71