Mineral nutrition and yield of pineapple plant cv. Pérola as a function of the K/N relationships in fertilization

Abstract

The pineapple fertilization should include the replacement of the amounts of N and K absorbed by the plant and exported by the fruits and slips, and appropriate relations between doses of these nutrients. This study evaluated the effect of different K / N on mineral nutrition and yield of pineapple 'Perola' in Coastal Tablelands soils of Paraiba. The experiment was conducted in a randomized complete block design with 13 treatments and three replications. The treatments consisted of combinations of four K / N (0.85:1, 1:1, 2:1 and 3:1), two N levels (7.2 and 10.8 g plant-1), four additional treatments (K / N of 2:1 at the highest dose of N, varying the source, the subdivision, date and manner of application of both N and K) and a control (without fertilization).The increase in K / N increase the weight of the 'D' leaf, the contents of K and the values for K / N and K / Mg; decreased the contents of N, but did not affect the content of P, Ca and the relationship K / Ca. The increase in K / N did not affect weight, productivity and the percentage of fruit class I, II and III. The use of K sulfate, split doses of N and K as KCl, in five applications and the application of half doses of foliar N and K in a ratio of 2:1 increase the weight of the 'D' leaf, the contents of N and values of average weight, productivity and the percentage of fruit class II.