Proportions of mineral and organomineral fertilizers in onion cultivation

Abstract

Organomineral fertilizers is an innovation in agriculture, since it uses organic matter enriched with minerals. The combination of mineral phosphate and organomineral fertilization can contribute to the development of a more sustainable and economical fertilization program for the crop. So, organomineral fertilization can be an alternative or complement to mineral fertilization. However, the careful selection of fertilizer sources and doses is essential to increase productivity in the onion crop and finding proportions between different fertilizers can be a promising choice for sustainable agriculture. The aim of the present research was to evaluate the effect of different proportions of mineral and organomineral fertilizers on the development, production and post-harvest quality of onion bulbs, cv. Sublime F1, under Cerrado conditions. The experiment was carried out in the field, in Cristalina, GO, Brazil, in a randomized block design, with four replications. Six treatments were used: five proportions of mineral fertilizer (M) with organomineral (OM) and the control (without additional fertilization). It was evaluated: length, width and number of leaves; productivity; soluble solids content; titratable acidity; and loss of fresh mass. Data were submitted to analysis of variance (ANOVA), at 1% (p≤0.01) and 5% (p≤0.05) of significance, and means compared by Tukey and Dunnett tests (p≤0.01 and p≤0.05). The fertilization proportions were submitted to regression (p≤0.05). The proportion of 50%M50%OM promotes higher bulb average mass and class 4 onion productivity. The proportions of fertilizers did not alter the postharvest characteristics (total soluble solids and total acidity) of the onion, which were affected only by the time of storage. Cultivar Sublime F1 showed good development for the region, conditions and fertilizers used.