Evaluation of Proportionate Combinations of Indigenous Rice Bran and Mineral Fertilizer for Improved Performance of Tomato (Lycopersicon lycopersicum) under Low Fertile Soil Conditions

Under tropical soil conditions, where soils are mostly marginal and deliberate fallowing of farmlands is very uncommon, integration of two or more different fertilizer materials, at pre-determined proportions, may be beneficial to soil quality improvement and enhanced crop productivity. Field experiment was carried out in the year 2015, at the Teaching and Research Farms, Ladoke Akintola University of Technology, Ogbomoso, Nigeria, to determine the complementary effect of organic and inorganic fertilizer at different rates on the performance of tomato, under low fertile soil conditions. Six treatments including the control were used: No fertilizer application, 100% N.P.K, 75% N.P.K + 25% Rice bran, 50% N.P.K +50% Rice bran, 25% N.P.K+ 75% Rice bran and 100% Rice bran arranged in randomized complete block design (RCBD), replicated three times. Data were collected on growth and yield parameters, and analysed using Analysis of variance (ANOVA). Means were separated using Duncan multiple range test (DMRT) at 5% level of probability. Results showed that amended plots significantly enhanced tomato growth, yields and nutrient uptakes higher, compared to the control. Sole application of 100% NPK and Rice bran significantly improved fruit yield by 831.5% and 597.1% respectively, while their combinations significantly enhanced tomato fruit yield ranging from 819% to 1127%. These indicate that combined application of organic and inorganic fertilizer is better than sole application. Also, significantly prolonged leaf production was observed (which equally promoted prolonged flowering and fruiting), in tomato plants which received Rice bran applications at 50% level and above. Therefore, since there is an increasing awareness nowadays, on the environment friendly benefits of applying organic materials to farmlands, application of either 75% or 100% NPK fertilizer should be totally discouraged. Hence, 75% Rice Bran + 25% NPK could be recommended or alternatively 50% Rice Bran + 50% NPK, for tomato production in the study area. This will improve soil organic matter content, reduce soil chemical fertilizer loads or inputs and alleviate the residual effects of synthetic fertilizer, for improved soil quality and tomato production, in the study area.