ARAÚJO, J. A. C.; http://lattes.cnpq.br/8214275745785513; ARAÚJO, João Aprígio Cabral de.
Résumé:
The present work aimed to study the response of sugar apple (Annona squamosa L.) to the addition of nitrogen, phosphorus and potassium levels and irrigation shifts in a Fluvial Neosol in the semi-arid region of the state of Paraíba, Brazil. This was carried out under plastic tunnel conditions, at the Center for Agro-Food Science and Technology, at the Federal University of Campina Grande, Pombal Campus. The experimental design used was randomized blocks, with five replications, in a 6 x 2 factorial scheme, with treatments consisting of six levels of nitrogen, phosphate and potassium fertilization (Organic Fertilization, NPK25% + Organic Fertilizer, NPK50% + Organic Fertilizer, NPK75% + Organic Fertilizer, NPK100%, NPK100% + Organic Fertilizer) and two irrigation shifts (TR1 - daily irrigation and TR2 - irrigation every two days), totaling 60 experimental units. Two to three fertilizer applications were performed per crop cycle. The following variables were evaluated: number of seeds, seed mass, peel mass, pulp mass, fruit mass and °Brix. The nutrient levels and watering shifts significantly affected the number of seeds, seed mass, peel mass, pulp mass, fruit mass and °Brix of the custard apple fruits, and the application of the treatment with half of the recommendation of fertilization for the sugar apple crop, NPK50% + organic fertilizer was the one that promoted the best results for the analyzed variables, with the exception of the variable soluble solids or °Brix, where the treatment NPK25% + organic fertilizer favored the production of sugar apple fruits with higher mean values regardless of the irrigation shifts applied. For the irrigation shifts, it was observed that the daily management of irrigation becomes necessary for the highest production and quality of fruits. Therefore, based on the studies carried out, organic fertilization associated with mineral fertilization NPK50% is recommended to fruit growers as a way to increase the production and quality of sugar apple fruits in the climate and soil conditions in which the present research was developed.