02705naa a2200337 a 450000100080000000500110000800800410001902200140006002400390007410000200011324501640013326000090029730000090030652016730031565000150198865000230200365000240202665000210205065000200207165000170209165000230210865000110213165000260214265000220216865000210219070000240221170000240223570000180225970000250227777300650230221399872023-02-05       2021    bl uuuu     u00u1 u    #d  a0926-66907 a10.1016/j.indcrop.2020.1131782DOI1 aSEVERINO, L. S.  aNutrient content of solvent-extracted castor meal separated in granulometric fractions by dry sieving and applied as organic fertilizer.h[electronic resource]  c2021  a7 p.  aCastor meal is the main by-product of the industrial oil extraction of castor seed (Ricinus communis L.). It was observed that castor meal could be separated by sieving into apparently distinct fractions. This study measured the relative weight and the nutrient content of six granulometric fractions of castor meal separated by sieving and tested the hypothesis that the fractions with lower N content have a longer residual effect when used as organic fertilizer. Samples of solvent-extracted castor meal were sieved in meshes with openings varying from 9.5 to 0.11 mm. The relative weight of each fraction was measured and calculated, and the nutrient content was determined. In another experiment, the meal was sieved into only three fractions for being tested as organic fertilizer for cotton (Gossypium hirsutum L.) plants for two consecutive growth cycles without additional organic fertilization. The finest fraction (particles &lt 0.11 mm) had a relative weight of 3.53 %, and the highest relative weight (32.85 %) was found in the fraction with particles between 1.0 and 2.0 mm. The finer were the particles, the higher was the content of N, P, K, Mg, and S, and the lower was the content of Ca. All the castor meal fractions were effective as organic fertilizer for cotton plants. The only difference among fractions was the nutrient content. The evolution of CO2 by microbial respiration confirmed that all the three fractions of castor meal were completely mineralized within one month. Castor meal fractions had no residual effect for supplying N to cotton plants cultivated in the same soil for the second cycle without additional organic fertilization.  aCastor oil  aMicrobial activity  aOrganic fertilizers  aResidual effects  aEfeito Residual  aFertilizante  aGossypium Hirsutum  aMamona  aMicrobiologia do Solo  aPlanta Oleaginosa  aRicinus Communis1 aMENDES, B. S. da S.1 aSABOYA, R. de C. C.1 aBARROS, L. A.1 aMARINHO, D. R. de F.  tIndustrial Crops and Productsgv. 161, 113178, p. 1-7, 2021.