Efeito do conteúdo de água do solo, densidade de plantio e fertilização nitrogenada na produção da cebola (Allium cepa L.).

Abstract

The present study had as main objective to study the effects of different soil water contents, planting densities and nitrogen fertilization on the production of onion (Allium cepa L.). The works were conducted at the São Francisco Sub-Medium Experimental Station belonging to the Brazilian Agricultural Research Corporation (EMBRAPA), located in Petrolina, Pernambuco. The moisture treatments tested were to irrigate the onion when 25, 50, 75 and 100% of the available water were consumed. The population treatments were 330. 000, 400. 000 and 500,000 plants / ha and nitrogen fertilization treatments were applications of 0, 75, 150 and 225 kg / ha of nitrogen in the form of urea. The variety of onion tested was Amarela Chata from the Canaries. The experimental design used to study the effects of the above parameters on onion production was randomized blocks with split-split-plot plots. The evaluation of the effect of different soil water contents, planting densities and nitrogen fertilization on the onion production was based on the average yields obtained in kg / ha in the different treatments. The analysis of the obtained results allowed to verify that the production of the onion increased with the availability of the water of the soil, with the population and with the levels of fertilization applied. Based on the results obtained, in order to obtain good yields of irrigated onion in the São Francisco Sub-Medium, it could be recommended that the crop should be irrigated when 25% of the available water of the planted soil was consumed at a spacing of 8 cm between plants and should be fertilized with a dose of 150 kg / ha of nitrogen.