EFFECT OF COMBINED APPLICATIONS OF VERMICOMPOST AND FERTILIZERS ON THE YIELD OF SUMMER ONION

Abstract

A held experiment was conducted at the Shcr-e-Bangla Agricultural University Farm, Dhaka 1207 during the summer season of 2007 to study the effect of "Combined application of vermicompost and fertilizers (NPKS) on the yield of summer onion". The experimental soil was silty clay loam in texture having pFI of 6.0. The treatments were 4 levels of vermicompost viz, V0 (0 t ha4). V, (1.5 I ha4), V, (3 t ha4).V3 (5 t haS'). and 3 levels of chemical fertilizers, viz. F0 = No NPKS (0-0-0-0 kg ha'). F1 = Ilali the recommended dose of NPKS (60-22 50-16 kg ha4), F2 = Full recommended dose of NPKS (120-44-100-32 kg ha') in 12 treatment combinations and 3 replications. The results demonstrated that the increasing doses of vermicompost and chemical fertilizers in combination increased bulb yield of summer onion significantly. The maximum significant bulb yield was obtained with the treatment combinations of V3F1 (Nigh vermicompost + Medium NPKS) or \'2F2 (Mediuni vermicompost -I- 1-ugh NPKS). The highest doses of vermicompost and chemical fertilizers increased N, P. K and S concentrations in summer onion plant and bulb significantly at the hervesting stage. Application of chemical fertilizers failed to increase organic matter content of post harvest soil, whereas vermicompost showed a significant positive effect. Combined appLication of vermicompost and chemical fertilizers increased the level of NPKS and organic matter status of soil significantly. Application of vermicompost and chemical fertilizers in combination prevents the development of acidity in the postharvest soil.