Accumulation of nutrients and growth in castor bean plants
Information about nutrient uptake and accumulation by different crops during development stages allows identifying periods of higher demand and an adequate fertilization management. An experiment under field conditions was carried out in order to evaluate macro and micronutrient accumulation in castor bean leaf tissue, as well as to identify nutrient uptake critical stages of this crop. Treatments were consisted of evaluation periods with samples collected every ten days until 160 days after emergence of crop. Castor bean plants showed higher macronutrient accumulation in descending order: N > K > Ca > S > Mg > P and the following micronutrients Fe > Mn > Zn > B > Cu > Mo. The highest accumulation rates of N, P and K nutrients occur from 20 to 110 days after emergence (DAE) with the highest N uptake from 30 to 40 DAE, remaining high until approximately 110 DAE. Regarding potassium, the highest uptake occurs between 40 and 50 DAE, with high uptake rates until approximately 110 DAE. The highest phosphorus uptake was between 80 and 90 DAE. The majority of macro and micronutrients were accumulated in leaves during most part of evaluation cycle.