EFFECTS OF VERMICOMPOST AND BLENDED NPSB FERTILIZER RATES ON GROWTH, YIELD COMPONENTS AND YIELD OF MAIZE (Zea mays L.) AND SELECTED SOIL PHYSICO CHEMICAL PROPERTIES AT BAKO, CENTRAL ETH

Abstract

Low soil fertility is one of the major soil chemical constraints which limit maize productivity in central Ethiopia. To increase the fertility status of the soil that can increase productivity and income, the use of integrated vermicompost and blended NPSB inorganic fertilizer is required. Thus, the experiment was conducted to evaluate the effect of different rates of vermicompost and blended NPSB fertilizer on growth, yield and yield components of maize, to determine the effects of vermicompost and blended NPSB fertilizer on major physicochemical properties of soil and to identify economically feasible rates of vermicompost and blended NPSB fertilizer for maize production at Bako. Factorial combinations of four levels of vermicompost (0, 2, 4 and 6 tons ha-1 ) and four levels of NPSB blended inorganic fertilizer (0, 50, 100 and 150 kg ha-1 ) were laid out in Randomized Complete Block Design (RCBD) with three replications.The results showed that stand count at harvest, ear length, number of ears per plot and days to maturity were significantly influenced by the main effects of vermicompost and blended NPSB fertilizer application rates. The interaction of vermicompost and NPSB blended inorganic fertilizer had a significant effects on ear diameter, grain yields, harvest index, cob weight and moisture content (%). The maximum grain yield (7503.7 kg ha 1 ) was obtained from application of blended NPSB fertilizer at the rate of 100 kg NPSB ha-1 and 4 tons ha-1 vermicompost rate with a net profit of 104850 birr and 6143% MRR with values to cost ratio of 3.47 birr profit per unit investment for midland maize production at Bako. Thus, it can be concluded that application of 4 t vermicompost ha-1 and 100 kg NPSB ha-1 was proved to be superior with respect to grain yield as well as economic advantage and is tentatively recommended for use. However, as this study was done for one season at one location, the experiment has to be repeated over years to reach at a conclusive recommendation