Effects of Scattered Erythrina brucei Trees on Wheat Yield and Soil Physicochemical Properties in Bonke District, Gamo Zone, Southern Ethiopia

Abstract

Abstract Erythrina brucei is multipurpose farm tree in Bonke district, Gamo Zone, Southern Region. The large amount of leaf litter it sheds during the dry season coupled with its rapid decomposition for the cropping season attracts farming family’s attention to retain in their farmland. Therefore, the current study was carried out with the aim of evaluating soil physico-chemical properties and wheat yield under scattered Erythrina brucei trees in farmland. Five trees on similar slope of land with relatively similar age, DBH (diameter at breast height), tree height, and canopy diameter were selected. The tree canopy diameter was divided into three distances: inner, middle and periphery. An open area at least double distance away from tree canopy was located for control. Soil samples at 0-30cm soil depth from three canopy distances and open control were taken for analysis of selected soil physico-chemical properties. Data were also recorded on growth, yield and yield attributes of wheat. The result of soil analysis revealed that with the exception of soil texture and soil pH, all soil properties increased significantly under Erythrina brucei canopy than in the open area showing a decreasing trend with increasing distance from the tree trunk. The result also indicated highest wheat yield at inner distance with yield increments of 18.17% compared to open control. We recommend optimal density of 100 Erythrina trees integration to enhance wheat yield in the study district and elsewhere with similar agroecology.