Agronomic performance of sweet potato genotypes under management of liming and mineral fertilization

Abstract

Our aim was to evaluate the agronomic performance, the use of limestone, and NPK fertilizer on sweet potato genotypes during two consecutives agricultural years (2009 and 2010). We conducted the experiment by using a randomized block design with twenty-one treatments (seven genotypes and three combinations of the use of limestone with mixed NPK fertilizer) in three blocks. The studied treatments were a control (no liming and no mineral fertilization), reduced management (liming and no mineral fertilization), and conventional management (liming and mineral fertilization). We evaluated commercial and roots yields, root diameter, root length, and shoot biomass yield. Database was analysed by using analysis of variance (F-test) and Bonferroni test at 5% of probability. Sergipana Branca genotype had the highest commercial and roots yields, root diameter and root length. Among the studied treatments, both minimum and conventional management promoted increases in all evaluated agronomic variables. The results of this study emphasize the importance of considering using liming and mineral fertilization in high yield farming systems. In family farming systems, however, using limestone becomes a minimum practice of soil fertility management that can improve yield of sweet potatoes while having a low benefit-cost ratio.