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The objective was to evaluate the productivity and nutrient concentration in spineless cactus ‘Miuda’ (Nopalea cochenillifera Salm Dyck) under levels of nitrogen (N) fertilization (0, 150, 450 and 600 kg N ha-1 year-1), P fertilization (0 and 150 kg P2O5 ha-1 year-1), plant densities (5,000 and 40,000 plants ha-1) in two sites (Caruaru and Sao Bento do Una). The productivity was greater in plots with 40,000 plants ha-1, regardless of the site, with average of 16.8 and 7.2 t DM ha-1 two years-1, for 40,000 and 5,000 plants ha-1, respectively. In plots with 5,000 plants ha-1, nitrogen fertilization did not affect productivity, however, there was a linear increase in plots with 40,000 ha-1 plants. The plant N concentration increased with nitrogen fertilization and ranged from 7.3 to 9.9 g kg-1. The plant phosphorus (P) concentration was influenced by the interaction between all the factors evaluated and reduced until estimated fertilization of 322 kg N ha-1 in plots with 40,000 plants ha-1 and 150 kg P ha-1 and only in Sao Bento do Una, with P concentration of 1.19 g kg-1. Nitrogen fertilization increased N concentration in cladodes and productivity when using high plant density. The increase in planting density increases productivity and reduces the concentration of most nutrients, except sulphur (S). |
