|Mattos, jr, Dirceu|
Submitted to: Scientia Agricola
Publication Type: Peer reviewed journal
Publication Acceptance Date: 12/1/2002
Publication Date: 1/1/2003
Citation: MATTOS, JR, D., QUAGGIO, J.A., CANTARELLA, H., ALVA, A.K. NUTRIENT CONTENT OF BIOMASS COMPONENTS OF HAMLIN SWEET ORANGE TREES. SCIENTIA AGRICOLA, 60:155-160. 2003. Interpretive Summary: The production of total dry matter in crop plants is an indication of its growth and potential for crop yields of economic significance. The carbohydrate and nutrients from vegetative portion of the plant/tree are distributed to the production of yields of economic significance, i.e. fruit production and/or quality for orange trees. Dry matter distribution in various parts of 6-yr old 'Hamlin' orange trees (on 'Swingle Citrumelo' rootstock) decreased in the order: fruit (30.3 percent) > root (27.8 percent) > twig (26.1 percent) > leaf (9.7 percent) > trunk (6.3 percent). Concentrations of various nutrients in 6-mo old spring flush showed that most nutrients were in the adequate to optimal recommended concentrations. The most abundant nutrient elements in the tree were: Ca, N, and K, which accounted 273.8, 234.7, and 181.5 g/tree, respectively. The amounts of N, K, and P in the 6-yr old trees on per hectare basis accounted 66.5, 52.0, and 8.3 kg/ha.
Technical Abstract: The knowledge of the nutrient distribution in trees is important to establish sound nutrient management programs for citrus production. Six-year-old Hamlin orange trees (Citrus sinensis L. Osb.) on Swingle citrumelo (Poncirus triboliata L. Raf. x Citrus paradisi Macfad.) rootstock, grown on a sandy Entisol ini Florida were harvested to investigate the macro and micronutrient distributions of biomass components. The biomass of aboveground components of the tree represented the largest proportion of the total. The distribution of the total tree dry weight was: fruit = 30.3 percent, leaf = 9.7 percent, twig = 26.1 percent, trunk = 6.3 percent, and root = 27.8 percent. Nutrient concentrations of recent mature leaves were in the adequate to optimal range as suggested by interpretation of leaf analysis in Florida. Concentrations of Ca in older leaves and woody tissues were much greater than those in the other parts of the tree. Concentrations of micronutrients were markedly greater in fibrous root as compared to woody roots. Calcium made up the greatest amount of nutrient inthe citrus tree (273.8 g per tree), followed by N and K (234.7 and 181.5 g per tree, respectively). Other macronutrients comprised about 11 percent of the total nutrient content of trees. The contents of various nutrients in fruits were: N = 1.20, K = 1.54, P = 0.18, ca = 0.57, Mg = 0.12, S = 0.09, B = 1.63 x 10-3, Cu = 0.39 x 10-3, Fe = 2.1 x 10-3, Mn = 0.38 10-3, and Zn = 0.40 10-3 (kg/ton). Total contents of N, K, and P in the orchard corresponded to 66.5, 52.0, and 8.3 kg ha-1, respectively, which were equivalent to the amounts applied annually by fertilization.