Nutrition and yield of 'Gigante' cactus pear cultivated with different spacings and organic fertilizer/ Nutricao e produtividade de palma forrageira 'Gigante' cultivada com diferentes espacamentos e adubacao organica

The objective of this study was to evaluate the levels of macronutrients in cladodes and yield of cactus pear, cv. 'Gigante, cultivated with different cattle manure doses and plant spacings. The experimental design was randomized blocks in 4 x 3 factorial, with three replicates. The treatments consisted of the combination of four doses of cattle manure (0, 30, 60 and 90 Mg [ha.sup.-1] [year.sup.-1]) with three spacings (1.00 x 0.50, 2.00 x 0.25 and 3.00 x 1.00 x 0.25 m). The contents of macronutrients and dry matter production of cladodes were assessed 600 days after planting. The plant spacings influenced the contents of nitrogen, potassium, calcium and sulfur in the cladodes of 'Gigante' cactus pear and there was interaction between spacing and manure dose for magnesium contents. The increment in cattle manure doses increases the contents of phosphorus, nitrogen, potassium and sulfur in the cladodes. The maximum dry matter production of cladodes is estimated at 21.8 Mg [ha.sup.-1] [year.sup.-1] at a dose of 71.8 Mg [ha.sup.-1] [year.sup.-1] of manure. Key words: Opuntia plant arrangement natural fertilization nutrients O objetivo deste trabalho foi avaliar os teores de macronutrientes nos cladodios e o rendimento da palma forrageira 'Gigante' cultivada com diferentes doses de esterco bovino e espacamentos de plantio. O delineamento experimental foi em blocos ao acaso no esquema fatorial 4 x 3, com tres repeticoes. Os tratamentos constaram da combinacao de quatro doses de esterco bovino (0; 30; 60 e 90 Mg [ha.sup.-1] [ano.sup.-1]) com tres espacamentos (1,00 x 0,50, 2,00 x 0,25 e 3,00 x 1,00 x 0,25 m). Aos 600 dias apos o plantio foram avaliados os teores de macronutrientes e a producao de massa seca de cladodios. Os espacamentos influenciaram os teores de nitrogenio, potassio, calcio e enxofre nos cladodios da palma forrageira 'Gigante' havendo interacao entre espacamento e dose para os teores de magnesio. O aumento das doses de esterco bovino eleva os teores de fosforo, nitrogenio, potassio e enxofre nos cladodios. A maxima producao de massa seca de cladodios e estimada em 21,8 Mg [ha.sup.-1] [ano.sup.-1] com dose de 71,8 Mg [ha.sup.-1] [ano.sup.-1] de esterco. Palavras-chave: Opuntia arranjo de plantas fertilizacao natural nutrientes