MANGANESE MINERAL NUTRITION OF UPLAND RICE CULTIVARS

Abstract

Manganese promotes expressive effects on plant nutrition, decreasing yield at toxic or deficient levels. The research was carried out to evaluate the response of upland rice cultivars to Mn fertilization, at tillering stage, in a cohesive Yellow Latosol. The experiment followed a completely randomized design, with four replicates, with treatments arranged in a 3x5 factorial scheme. These factors consisted of three upland rice cultivars (Carisma-1999, Conai-2004, and BRSMG Curinga-2004) and five Mn rates (0 mg dm^-3, 10 mg dm^-3, 20 mg dm^-3, 30 mg dm^-3, and 40 mg dm^-3). High purity MnSO₄ was applied to soil as Mn source. Carisma cultivar presented the smallest dry matter production. For all cultivars, Mn content was above appropriate content levels, independently of soil applied rates. Fe and Mn content were influenced by rates and cultivars factors alone and significant difference was found for interaction between the studied factors and Ca, S, Cu, and Zn content.

KEY-WORDS: Oryza sativa L.; tillering stage; Mn fertilization; micronutrients.