Mitigating Iron Toxicity by Using Rock Phosphate to Improve Rice Productivity

Abstract

Iron toxicity is a major constraint to rice production, particularly in highly weathered soils of inland valleys in Sub-Saharan Africa where the rice growing area is rapidly expanding. This study aimed to improve the productiveness of iron toxicity sensitive’s rice fields as well as in the unsensitive fields by using local phosphate fertilizers. Eighteen (18) rice genotypes were been assessed in a split plot design in two areas: without iron toxicity and with iron toxicity. NPK, NK, Rock Phosphate, Triple super phosphate, Calcined phosphate and Acidulated phosphate were used as fertilizers. Data collection was focused on agronomic traits and yield (g/m²). The best fertilizers in the area without iron toxicity were NPK (820.2 g/m²) and triple super phosphate (751.7 g/m²). In the iron toxicity area, the best yields were performed by NPK (785.5 g/m²) and raw calcined phosphate (698.3 g/m²). Yet, the Accessions 15, Accessions 225, Accessions 226 and Accessions 270 were rainfed rice genotypes while CC109 A, HB 46 and HB 62 were low-land/irrigated rice genotypes. NPK, NK and acidulated phosphate fertilizers alleviate the best, iron toxicity in both sensitive and unsensitive rice fields.