Soil acidity problem is one of the bottlenecks to improve crop production in high rainfall regions of Ethiopia in general and in Banja district particular. This study aimed to determine the residual effect of lime and P fertilizer on the acid properties of soils and to develop models whereby the change in acidity indicators of soils can be predicted as a result of lime application. The experiment was laid out in a randomized complete block design with three replications. Five levels of lime (0, 1.15, 2.3, 3.45, 4.6 t ha-1) and four levels of Phosphorous (0, 10, 20, and 30 kg ha-1) were combined in a complete factorial arrangement. The study was conducted for three consecutive years from 2015 to 2017 main cropping seasons at Banja district. Mean grain yield and yield components as affected by different levels of lime and phosphorus fertilizer. Analysis of variance showed that all limed treatments were higher mean values of grain yield and yield components relative to control plot (no lime and P) in all over combined cropping years. Moreover, over year combined mean the highest grain yields (1115.9 kg ha-1), biomass yields (3591.2 kg ha-1), number of seeds per plant (21.54), plant height (64.50 cm) and spike length (5.24 cm) were recorded under 4.6 t ha-1 of lime application of plot. The lowest grain and biomass yields were recorded in control plots. However, over year mean 4.6 t ha-1 of lime application plot the grain yield and biomass yield of wheat were increased by (151.1%) and (123.3%) related to the control plot, respectively. Hence, lime application at the rate of 3.45 t ha-1 (150% of the lime requirement of the soils based on its exchangeable acidity) coupled with 20 kg ha-1 P fertilizer could serve as a reference to boosting wheat production in the study area and similar areas with possible re-liming of the soils in every five years.
Keywords: Acidic soil, North Western Ethiopia, P Fertilizer, Phosphorus, lime
