Lime Application for Acid Soil Amelioration and Improving the Productivity of Barley in Semen Ari District, Southwestern Ethiopia

Abstract

Soil infertility constraints and low soil pH are the predominant problems to barley production and productivity in the highland regions of Ethiopia. In reaction to this, the experiment was carried out in highland areas of Semen Ari district with low soil pH to determine the effects of split application of lime on soil pH and grain yield of barley from 2018 to 2020 for three cropping years. Six treatments were used for this experiment as control (no inputs); 200 kg ha^-1 of NPKSZnB + 94 kg ha^-1 of urea top-dressed; lime applied at once (7.6 t ha^-1); two splits or 50% (1^st and 2^nd years); three splits or 33% (1^st, 2^nd and 3^rd years); two splits or 50% (1^st and 3^rd years). The RCBD design within three replications was employed to arrange treatments. The result of soil analysis after lime application revealed that it improved available phosphorus and raised the soil pH, but decreased the exchangeable acidity compared to control treatments. Among the treatments, lime application in two splits (1^st and 3^rd years) gave the maximum grain yield (3061.5 kg ha^-1) of barley significantly, whereas the minimum yield was obtained from the control (untreated plot). The maximum grain yield in the third year was obtained from the application of two splits or 50% (1^st and 3^rd years) which were statistically non-significant with the application of three splits or 33% in each year (1^st, 2^nd and 3^rd years) and two splits or 50% (1^st and 2^nd years). Thus, to enhance soil fertility status and obtain better barley grain yield, farmers must undertake the use of a split application of lime with inorganic fertilizer rather than a sole application of inorganic fertilizer. It suggested that, depending on the accessibility of lime and affordability of barley producers, farmers in the study area could use the above application frequencies with recommended inorganic fertilizers (69N and 46P₂O₅). Further investigation should be done on plant nutrient uptake, nutrient use efficiency and optimization.