CASCA E TORTA DE MAMONA AVALIADOS EM VASOS COMO FERTILIZANTES ORGÂNICOS
The hulls and the presscake, the two most important residues of castor processing and industrialization, are traditionally used as organic fertlizer. This study aimed to evaluate these residues as organic fertilizers in vases in order to optimize doses and promove the best use of their chemical properties. A trial was run in a randomized block design with four replications and eight treatments: four doses of castor presscake (0,5; 1,0; 1,5 e 2,0 t/ha) and four doses of castor hulls (0,5; 1,0; 1,5 e 2,0 t/ha) with addition of nitrogen fertilizer. Seeds of CSRN 393 castor bean line were planted in 22 liters vases. At 60 days after emergence, values of height, stem diameter, leaf area and total dry weight were taken. Castor bean presscake was showed to be a good organic fertilizer, mainly due to its high N content, however castor hulls was showed to be inappropriate as organic fertilizerdue to its high C/N ratio that cause nitrogen deficiency.
Liv Soares Severino, Rosiane de Lourdes Silva de Lima, Robson César Albuquerque, Napoleão Esberad de Macêdo Beltrão, Lígia Rodrigues Sampaio
Universidade Federal Rural do Semi-Árido