Effect of Nitrogen-Fortified Rice Mill Waste on the Growth and Yield of Maize (Zee Mays) and Its Influence on Soil Chemical Properties in South Eastern Rainforest of Nigeria

Abstract

Organo-mineral nutrients sources are promising soil amendments for sustainable crop production in Nigeria. A field experiment was conducted at the Teaching and Research Farm of the Cross-River University of Technology Obubra during the 2016 cropping season. The objective of the study was to eradicate the effects of nitrogen amended Rice mill waste (RMW) on some soil chemical properties and yield of maize (Zee mays L.) the treatments consist of 10ha^-1 Rice mill waste as control and 10ha^- of rice mill waste amended with 10 KgNha^-1, 20 KgNha^-1, 30 Kg Nha^-1, 40 Kg Nha^-1, 50 KgNha^-1. The six treatments were replicated three times under RCBD with each experimental plot size measuring4mí—3m. Result obtained showed that all the treatments including control increased the chemical properties of the soil over the initial soil properties including total N, available P, Som, pH and the exch. Cations of Ca2⁺, K⁺, Mg²⁺ Na⁺. RMW + 40 Kg N/ha and RMW 50 KgN/ha produced tallest plants, highest number of leaves per plant and largest leaf area of maize plants.  RMW+ 30 KgNha^-1, RMW+ 40Kg Nha^-1 and RMW+ 50Kg Nha^-1 produced highest number of seeds per cob, highest plant dry matter and highest grain yield per unit area of 2.61 t/ha and 2.59 t/ha respectively in 2016 and 2.63 t/ha and 2.62 t/ha grain yield in 2017 while the least grain yield was obtained from the control (0.81 t/ha and 0.83 t/ha respectively for 2016 and 2017). Rice mill waste amended with 30 Kg N ha^-1 is therefore recommended for optimum economic yield of maize in Obubra Rainforest soil and the improvement of soil chemical properties for sustainability.