Effect of lime rates and method of application on soil properties of acidic Luvisols and wheat ( Triticum aestivum , L.) yields in northwest Ethiopia.

Soil acidity has become a major constraint that threatens sustainable agricultural production in Ethiopia. This study was conducted to evaluate effects of lime rates and application methods on selected soil properties and wheat (, L.) yields on acidic Luvisols of northwestern Ethiopia. The treatments included control, 0.5, 1, 2 and 3 t ha lime drilled along the seed rows and 2, 3, 6 and 12 t ha lime applied in broadcasting method. The experiment was arranged in a randomized complete block design (RCBD) with three replications. Lime rates applied for this experiment were quantified using exchangeable acidity and Buffer pH methods. To analyze selected soil properties, composite soil samples were collected immediately before sowing and after harvest. Results revealed that liming significantly increased soil pH, available phosphorus, and exchangeable bases but markedly reduced exchangeable Al contents. The lime rates determined by buffer pH method were greater in ameliorating soil acidity, increasing soil nutrients status and crop yields than exchangeable acidity. Besides, lime application along the row was better in overcoming soil acidity constraints and increasing crop yields compared to broadcast application. Application of 12 t ha lime in the broadcasting method, 3 t ha and 2 t ha lime drilling along the row increased wheat grain yield by 65.10, 49.80 and 27.05%, respectively, compared to the control. Likewise, partial budget analysis showed that the highest net benefit (51,537 Birr ha) was obtained from plots amended with 3 t ha lime while the lowest economic profit (31,627.5 Birr ha) was recorded from treatments that received 12 t ha lime. Thus, we concluded that application of 3 t ha lime in row is a promising practice to mitigate soil acidity and increase available nutrients, exchangeable bases and crop yields in the study area and similar soil types elsewhere.