Production of yam fetilized with rates of N and bovine manure.

The objective of this study was to evaluate the behavior of the yam fertilized with rates of N and bovine manure. The study was conducted at the Universidade Federal da Paraiba, Areia-PB, in the period January to December 2010, the experimental design was randomized in blocks, with treatments distributed in 6 x 2 factorial, in four repetitions,were evaluated the rates of N (0, 50, 100, 150, 200 and 250 kg ha-1) in soil with and without bovine manure. The average mass of tubers of 2.1 and 1.9 kg were produced with the use of 141 and 118 kg ha-1 of N, respectively, with and without bovine manure,. The total productivity of tubers with bovine manure was 24 t ha-1 in the dose of 133 kg ha-1 of N, and without bovine manure obtained average productivity of 23 t ha-1. The maximum productivity of commercial tubers of 21 and 19 t ha-1 in rates of 99 and 154 kg ha-1 of N, with and without bovine manure, respectively. The leaf content of N of 33.74 and 34.51 g kg-1 in the rates of 148 and 250 kg ha-1 of N, respectively, in soil with and without bovine manure.