Adubação orgânica e Lithothamnium no cultivo da pitaia vermelha

The red pitaya is a fruit cactus native from the rainforests of Mexico, Central America and South America that has shown great potential in domestic and foreign markets, due to its hardiness and exotic appearance. The work was carried out to evaluate the influence of organic fertilizers and the application of Lithothamnium (calcified seaweed) on production and fruit quality of red pitaia [ Hylocereus undatus (Haw.) Britton & Rose]. The experimental design was a randomized block with eight treatments: control (no fertilization), cattle manure (CaM), chicken manure (ChM), calcified seaweed (CS), cattle manure + chicken manure, cattle manure + calcified seaweed, chicken manure + calcified seaweed and cattle manure + chicken manure + calcified seaweed. The fertilizers were applied every three months since September 2008, with three blocks, and the experimental unit consisted of four plants. The analyzes done were: yield , number of fruits per plant, fruit mass, pulp yield, transverse diameter, longitudinal diameter, peel thickness, soluble solids (SS), titratable acidity (TA), pH and SS/TA ratio. The highest productivities were obtained in treatments containing CaM + ChM + CS (7.16 t ha-1) and CaM + ChM (6.90 t ha-1) in 2011, and the first treatment also showed higher productivity in 2012 (9.40 t ha-1). Greater number of fruits per plant was obtained when fertilization was carried out with CaM + ChM + CS in the two years evaluated. There were no significant differences among the chemical characteristics of red pitaia fruits with different fertilizations.