Tillage Frequency, Soil Compaction and N-Fertilizer Rate Effects on Yield of Teff (Eragrostis Tef (Zucc) Trotter) in Central Zone of Tigray, Northern Ethiopia

Abstract

In Ethiopia, teff is grown for its grain and straw. There is a dearth of information with respect to plowing, compaction and fertilization on vertisols in central zone of Tigray. Therefore, this study was conducted to determine the effects of plowing frequency, soil compaction and N on teff yields. The experimental design was a split-split plot where main plot was plowing frequency with three levels (once, twice and thrice); sub-plot was compaction with two levels (with and without compaction) and sub-sub plot was N-fertilizer rate with four levels (0kg N/ha, 46Kg N/ha, 69Kg N/ha and 92Kg N/ha). There were three replications. Results showed that plowing frequency had no significant effect on most of the yield components except on tillering when the soil is compacted. Maximum average number of tillers per plant (2.75) was obtained from compacted plots plowed two times. Compaction affected almost all yield and yield components significantly. Higher number of tillers per plant (2.64) from non compacted plots and higher stand cover (about 94%) from compacted plots were found. In addition, maximum biomass (4210.617 kg/ha) and grain (1221.98 kg/ha) yields were obtained from compacted plots due to enhanced soil to seed contact resulting in increased plant population. Nitrogen fertilizer significantly increased grain yield and yield components. Maximum stand cover (94.78%), plant height (92.16cm), panicle length (37.75cm), biomass yield (4724 kg/ha) and grain yield (1387.9 kg/ha) were found from plots receiving 92kgN/ha. Partial budget analysis of N fertilizer rates indicted that higher marginal rate of return (525%) were found by applying 69kg N/ha. It is recommended that farmers use 69kg N/ha so as to get economically feasible returns and yield.

Keywords: Compaction, Fertilizer N, Plowing frequency, Teff, Vertisol.