Nutritional behavior, production and fruit quality of ‘Ponkan’ mandarin trees applying calcified seaweed

The present study was performed to evaluate the nutritional behavior, production and quality of fruits of ‘Ponkan’ mandarin trees using calcified seaweed. It was conducted in unirrigated orchard located in Perdões, the southern region of Minas Gerais, Brazil. The ‘Ponkan’ mandarin used were grafted on ‘Rangpur’ lime, thirteen years old, cultivated with spacing of 6 m x 3 m. The experimental design was the randomized block design with split plot in time, with four rates of calcified seaweed (0.0, 0.3, 0.6 and 1.2 kg plant-1) in the plot, and the two years of assessment (2010 and 2011) in the subplot. At harvest, leaves samples were collected from productive branches for analysis of nutrients. Production, transverse diameter, longitudinal diameter, mass, titatrable acidity, soluble solids and soluble solids/ titatrable acidity ratio of fruits were evaluated. The application of calcified seaweed increased the leaf levels of N, P, Ca and Mg at harvest. The level of K in the leaves of ‘Ponkan’ mandarin trees at harvest decreased with the rates of calcified seaweed per plant. The calcified seaweed rate of 0.8 kg per plant favored the production and improved the quality of ‘Ponkan’ mandarin fruits.