Response of corn (Zea mays L.) to various organic-based fertilizers in marginal upland of Sta. Rita, Samar

Abstract

Organic farming is one of the management strategies that improve productivity of marginal uplands. The study aimed to: (1) evaluate effects of various organic-based fertilizers on the growth and yield of corn; (2) determine the appropriate combination for optimum yield; and (3) assess changes on the soil physical and chemical properties. Experiment was laid out in Randomized Complete Block Design, with 3 replications and 7 treatments, namely; T₀=(0-0-0); T₁=1t ha^-1 Evans + 45-30-30kg N, P₂O₅, K₂O ha^-1; T₂=t ha^-1 Wellgrow + 45-30-30kg N, P₂O₅, K₂O ha^-1; T₃=15t ha^-1 chicken dung; T₄=10t ha^-1 chicken dung + 45-30-30kg N, P₂O₅, K₂O ha^-1; T₅=15t ha^-1 Vermicast; and T₆=10t ha^-1 Vermicast + 45-30-30kg N, P₂O₅, K₂O ha^-1. Application of organic-based fertilizers with or without inorganic fertilizers promoted growth of corn than the control. But due to high infestation of corn silk beetle(Monolepta bifasciata Horns), its grain yield was greatly affected. In the second cropping, except for Evans, any of these fertilizers applied alone or combined with 45-30-30kg N, P₂O₅, K₂O ha^-1 appeared appropriate in increasing corn earyield. Soil physical and chemical properties changed with addition of organic fertilizers. While bulk density decreased irrespective of treatments, pH, total N, available P and exchangeable K generally increased more with chicken dung application.