Evaluation of Integration Application of Vermicompost with Inorganic Fertilizers and Their Combination Effect on Maize Yield in Mettu District

The application of vermicompost and NPS fertilizer together increases crop productivity. However it is crucial to identify the combined application level. A field experiment was carried out in Mettu district in 2022/23 cropping season to determine the effect of integrated use of Vermicompost and inorganic fertilizers on the yield of maize and to determine the optimum rate of NPS fertilizer and Vermicompost on growth and yield of maize. Three levels of vermicompost (0, 1.5 and 3 t ha<sup>-1</sup>) and three levels of NPS fertilizer (0, 100 and 200 kg ha<sup>-1</sup>) were used for the study in randomized complete block design (RCBD) with three replicates. The interaction effect of NPS with vermicompost showed that significant differences on maize grain yield, days to tasseling and plant height. The highest maize grain yield (7861.10 kg ha<sup>-1</sup>) and (1597.20 kg ha<sup>-1</sup>) was obtained from the treatment combination of 3 t ha<sup>-1</sup> vermicompost with 200 kg ha<sup>-1</sup> NPS and 46 kg ha<sup>-1</sup> N. Whereas, the lowest grain yield (1597.20 kg ha<sup>-1</sup>) was gained from control plot. However, this combination was statically at par with the treatment combination of 1.5 t ha<sup>-1</sup> vermicompost with 200 kg ha<sup>-1</sup> NPS and 46 t ha<sup>-1</sup> N, which gave maize grain yield (7699.1 kg ha<sup>-1</sup>). Application of 200kg ha<sup>-1</sup> of NPS alone with recommended N ha<sup>-1</sup> fertilization is profitable and recommended for farmers. However, in terms of net benefit and soil health point of view for the study area 200kg ha<sup>-1</sup> NPS with 1.5t ha<sup>-1 </sup>was recommended.