Berta C. Ratilla1, Sataki P. Toledo2 and Othello B. Capuno3
Marginal uplands have low crop productivity due to poor soil fertility and continuous degradation. The study evaluated the effects of various organic- based fertilizers on the growth and yield performance of corn; determine the appropriate combination of organic and inorganic fertilizers for optimum corn yield; and assess changes in soil properties. The experiment was laid out in Randomized Complete Block Design (RCBD) in three replications with seven treatments: T0= (0-0-0); T1= 1 t ha-1 evans + 45-30-30 kg N, P2O5K2O ha-1; T2= 1 t ha-1 wellgrow + 45-30-30 kg N, P2O5K2O ha-1; T3= 15 t ha-1 chicken litter; T4= 10 t ha-1 chicken litter + 45-30-30 kg N, P2O5K2O ha-1; T5= 15 t ha-1 vermicast; and T6= 10 t ha-1 vermicast + 45-30-30 kg N, P2O5K2O ha-1.
Most agronomic characters as well as yield and yield components of corn were significantly affected by the treatments. Application of 10 t ha-1 chicken litter + 45-30-30 kg N, P2O5K2O ha-1 markedly enhanced height, leaf area index and stover yield of corn comparable with 10 t ha-1 Vermicast + 45-30-30 kg N, P2O5K2O ha-1. This treatment produced significantly higher grain yield in two croppings due to bigger ears and heavier seed weight over the untreated control and appeared the most promising combination. No remarkable changes in soil properties were noted except for an increase in available P and exchangeable K. Supplementation of organic with inorganic fertilizers is necessary to enhance productivity of marginal uplands.
Keywords: marginal uplands, chicken litter, evans, wellgrow, vermicast, inorganic fertilizers