Abstract:
This study was conducted on soil samples collected from Delbo Atwaro watershed, southern Ethiopia, during 2007/08 to study the nutrient(s) status for maize production. Soil fertility diagnostic techniques developed by Agro Services International (ASI), including soil testing, nutrient sorption study and pot experiments were conducted. Greenhouse experiment with 19 fertilizer treatments was conducted in a Completely Randomized Design (CRD) with four replications using maize as a test crop. Chemical analysis of composite soil samples indicated that Ca, Mg, Fe, Mn, Zn, B and Mo were sufficient to support good crop growth, whereas total N, available P, available Cu, S and K were deficient. Sorption studies of P, K, S, Cu and B indicated that the optimum levels of the nutrients for Alfisols of the Delbo Watershed were: 130 mg P, 30 mg K, 20 mg S, 3.0 mg Cu and 1.0 mg B per kg soil. Besides, P and Cu were found to be highly fixed by the soil. The results of soil analysis, dry matter yields, nutrient concentration and uptake by maize indicated that phosphorus and nitrogen to be highly limiting nutrients to support good crop growth and development. Furthermore, Cu, K and S are also potentially limiting nutrients.
|
