Mineral Nutrition N, P, K, Ca, Mg and Zn Effects on Ratoon Rice (Oryza sp.) NERICA 5 Variety growth Parameters and Grains Yield under Upland Rainfield Conditions

Rice is a staple food in Sub-Saharan Africa characterized by limited production. While ratooning potential of rice is not practiced. Thus, trials have been carried out in savanna zone ofCote d?Ivoire humid forest to evaluate mineral N, P, K, Ca, Mg and Zn nutrition effects on ratoon rice (Oryza sp.) Nerica 5 variety growth parameters and grains yields under upland rainfield conditions. Theday after main crop harvest previously fertilized with NPK (10-18-18) at sowing and N (46 %) at tillering and panicle initiation stages, seven treatments have been applied in a complete randomized bloc with four replications.60 kg Nitrogen, 33 kg TSP, 90 kg KCl, 21 kg CaCO3, 9 kg MgSO4, 10 kg ZnSO4per ha and 0 fertilizer as control were applied as basal dose. Fertilizers applied effects on ratoon were significant at 5 %. Tillers number were increased by Ca (207 Nbm-2) and N (214 Nbm-2) who increased panicles number (163-165 Nbm-2).50 % flowering period were reduced by minerals tested while only Ca allowed highest grains yield (1, 4-1, 5 tha-1) and agronomic efficiency (68, 77-74, 83 kg paddy / kg fertilizer) as Zn efficiency. Ca fertilizer application is recommended.