Study on Selected Metals and Nutritional Status of Maize (Zea mays L.) Grown under Different Rates of Fertilizers in Wolaita Zone, Southern Ethiopia

Background: The main aim of this study was to investigate the nutritional value of maize samples grown under the different rates of blended fertilizer in Wolaita Zone, southern Ethiopia. Methods: Maize samples that were grown under combined application of the two fertilizers (K and NPSB) with ratio rates of (0:0, 25:50, 50:100, 75:150 and 100:200) kg ha-1 were used as treatment. The content of nutrients from the maize was determined by flame atomic absorption spectrometry. Result: The mean concentration of metal in the maize sample ranged as (mg/kg): Ca (512.48-725.86), K (786.62-901.907), Mg (440.23-618.61), Fe (31.52-39.63), Zn (29.45-35.58), Pb (0.005-0.034), Cd (0.014-0.13). The study also revealed that the proximate analysis of the maize sample grown under different rates of blended fertilizer ranged as moisture (5.57-9.56%), ash (0.76-2.29%), fat (2.83-5.95%), fiber (0.93-2.25), 6.83-11.86% and Carbohydrate (68.08-83.07%). For most metals and nutritional values, the highest content was obtained in maize samples grown under the application of 100 K and 200 NPSB kg per hectare.