PRODUTIVIDADE DE SEMENTES DE CEBOLA EM FUNÇÃO DE CULTIVARES E DOSES DE NITROGÊNIO EM COBERTURA NA REGIÃO DE PONTA GROSSA – PR

Abstract

The experiment was ram in Ponta Grossa (PR) with the aim to evaluate onion seed yield of cultivars Bola Precoce e Crioula in function of four levels of nitrogen in covering. The bulbs used in the experiment weighed approximately 80 g each, and were vernalized before planting in cold room at 43 days at a temperature of 5 ± 1 º C and relative humidity of 80%. The experimental design was a randomized blocks with four replications. The treatments followed a split-plot design, being two cultivars (Bola Precoce e Crioula) and four levels of nitrogen in covering (0, 60, 120 and 180 kg ha-1). Bulbs were planted in 07/06/07. Nitrogen fertilization was applied in covering with urea at 55 days after planting. The harvest were realized at 192 days after planting. The following characteristics were evaluated: number of flower stems, fertilized flowers, no fertilized flowers and total flowers per plant, number of seeds per plant and per capsule, number of seeds per plant obtained from capsules with 1, 2, 3, 4, 5 and 6 seeds, weight of 1000 seeds, seed weight per plant and productivity. For the characteristics evaluated, Crioula was superior compared than Bola Precoce, with an increase of 43% in seed yield. Nitrogen fertilization is an important management in onion seed production; compared to control, it was the highlight for a level of 120 kg ha-1 with yield of 558.64 kg ha-1.