Mineral fertilization effect on growth and chemical composition of cactus pear – clone IPA 20

Abstract

The study was carried out in the greenhouse of the “Instituto Agronômico de Pernambuco - IPA”, located in Recife – PE. It aimed to evaluate the effects of P and K fertilization on growth and chemical composition of cactus pear IPA-20 clone. Four levels of P (0, 200, 400, and 800 kg P₂O₅ ha^-1) and four levels of K (0, 200, 400, and 800 kg of K₂O ha^-1) were tested in a 4 x 4 factorial arrangement using a complete randomized block design. Observations were made at 28-d intervals, starting by the third month after planting and lasting until the sixth month of growth. Fresh matter yield of primary articles and total fresh matter yield were affected only by K fertilization (P < 0.05). Concentrations of N, K, Ca, Mg, and S in the cactus shoot were affected by P fertilization (P < 0.05), however, P concentration was not affected. Potassium fertilization affected (P < 0.05) only Ca and S concentrations. Average results for N, P, K, Ca, Mg, and S were 20.62, 4.75, 33.43, 34.43, 7.44, and 6.10 g kg^-1, respectively. Fresh matter yield and dry matter concentration were affected only by K fertilization. Micronutrient concentration was not affected by P and K fertilization.