TISSUE NUTRIENT COMPOSITION OF LOWLAND RICE (Oryza sativa L.) VARIETIES AS INFLUENCED BY SOWING METHOD AND FERTILIZER MANAGEMENT IN THE NIGERIAN SAVANNA
The study aims to evaluate tissue nutrient composition of lowland rice varieties as influenced by sowing method and fertilizer management in Nigerian Savanna. Field trials were conducted at the Institute for Agricultural Research, Samaru, and Irrigation Research Station Kadawa in Northern Guinea and Sudan Savanna zones of Nigeria respectively, during 2020 and 2021 wet seasons. Treatments consisted of three (3) lowland varieties (Federation of Agricultural Research Oryza (FARO) (FARO 44, FARO 52, and FARO 57), four (4) rates of combined (Nitrogen, Phosphorus, Potassiun (NPK) and Agriczyme 3X organic liquid fertilizers (O.L) (0:0:0 kg NPK ha-1 plus 3L ha-1, 60:30:30 kg NPK ha-1 plus 1.5L ha-1, 60:30:30 kg NPK ha-1 plus 3L ha-1 and 120:60:60 kg NPK ha-1 plus 0L ha-1), and three (3) sowing methods (dibbling, drilling and broadcasting). These were factorially combined and laid out in a split plot design, fertilizer rate and planting method as main plots and lowland rice varieties as subplots replicated three times. The gross and net plot sizes were 3.0m x 4.0m (12m2) and 2m x3m (6m2) respectively. The results revealed Leaf tissue nutrient composition showed significant effects of variety, sowing method and fertilizer management on nitrogen, phosphorus and potassium concentrations. FARO 44 generally recorded the highest nitrogen concentration, drilling enhanced phosphorus and potassium uptake, while broadcasting generally increased nitrogen concentration, application of NPK fertilizer and Agric-Zyme 3X organic liquid fertilizer improved nutrient uptake and supports sustainable lowland rice production. In conclusion rice tissue nutrient composition was significantly influenced by variety, sowing method, fertilizer management and their interactions. FARO 44 showed superior nitrogen uptake, while drilling improved phosphorus and potassium uptake. Integrated use of inorganic and organic fertilizers enhanced nutrient use efficiency and offers a sustainable approach for improving lowland rice production in the Nigerian savanna.