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Camu-camu is an Amazonian fruit that has high levels of vitamin C, however, there is a need to expand knowledge to carry out systematic and consistent studies in the various fields of knowledge, and those related to mineral nutrition. The objective of this work was to evaluate the nutritional and growth status of camu-camu by the missing element technique and the use of liming, using as substratum a dystrophic Yellow Latosol of central Amazonian texture. The experimental design was a randomized block design with four replications and 15 treatments: complete, liming omission, individual omission of N, P, K, Ca, Mg, S, Zn, Mn, Cu, B, Cl and Mo. of the witness (natural soil). The characteristics evaluated were: height, neck diameter, leaf, stem, shoot, root and total dry matter, relative growth, shoot and root ratio, and nutrient accumulation of shoot (leaf) dry matter. All data evaluated were statistically significant. Liming and fertilization were necessary for acidic and low natural soils when comparing the complete with the control. Ca and P were the most limiting nutrients, while omission of N reduced the growth of seedlings. Based on total dry matter, the nutritional requirement of camu-camu was in decreasing order: Ca > P > S > Cl > Cu > Mg > Z > K > Mo > Mn > B > N.

Amazonian soils have some physical, chemical and mineralogical differences, understanding the differences is important to understand the behavior of nutrients in the soil, especially phosphorus. The study was carried out in two types of soils: a Hydromorphic soil profile and a Non-hydromorphic soil profile in the Central Amazon region of Brazil, located in the metropolitan area of Manaus. Five depths were sampled: 0.00-0.05; 0.05-0.1; 0.1-0.2; 0.2-0.4; and 0.4-0.6 m. Physical, chemical, mineralogical and morphological attributes of both soils were studied. With the exception of clay, the levels of sand and silt remained stable in depth. The levels of organic matter gradually decrease in depth. The pH in water and in KCl, ∆pH, point of zero load, were similar between the surface and subsurface soils. Al3+, H++Al3+, CECt, CECT and clay activity were similar in Non-hydromorphic soil and increase in surface (< 0.2 m) and stabilize in subsurface (> 0.2 m). In both soils, the bases are reduced in subsurface (> 0.2 m). Aluminum and iron oxalate reduce with greater expressiveness in Non-hydromorphic soil. Aluminum and dithionite iron exhibit the same behavior. The levels of Goethite (Gt) and Hematite (Hm) are high in depth in the Non-hydromorphic soil and decrease in the Hydromorphic soil. There are sensitive distinctions between soils, due to the imposed edaphoclimatic conditions.

O mogno (Swietenia macrophylla King), pelo elevado valor comercial da sua madeira, é uma das espécies mais exploradas na Amazônia, sendo ameaçada de extinção por não haver renovação dos estoques através de reflorestamento com a espécie. O objetivo deste trabalho foi avaliar o efeito da adubação fosfatada sobre o desenvolvimento de mudas de mogno. O estudo foi conduzidos em casa-de-vegetação e o solo utilizado para compor o substrato foi Latossolo Amarelo de textura muito argilosa. Os tratamentos constituiram-se de doses crescentes de fósforo de 0, 25, 30, 75, 100, 150 e 200 kg.ha-1 de P. O delineamento experimental foi o de blocos casualizados com 4 repetições, num total de 28 parcelas. Cada parcela foi formada por 2 mudas, cultivadas em sacos com capacidade de 4 dm³. Verificaram-se respostas positivas às doses de fósforo para todas as características de crescimento, bem como na absorção da maioria dos macronutrientes. Para as características de crescimento a dose de 200 kg.ha-1 de fósforo, foi a que proporcionou máximo crescimento para as mudas de mogno, no intervalo de 90 dias. ABSTRACT Due to the high value of mohogany woods (Swietenia macrophylla King), this specie is one of the most explored in the Amazon region. That explains the reason why mahogany is almost extinct.The present work evaluates the effect of phosphated fertilization on the mahogany seedlings under the increased doses of phosphorus. The experiment happened in a greenhouse and the soil used to compose the substratum was a yellow oxisoil with a very argillaceous texture. The treatments were made by doses of P: 0, 25, 30, 75, 100, 150 and 200 kg.ha-1 of P. The experimental design consisted of four randomized blocks, for a total of 28 parcels. Each parcel was formed by 2 seedlings, cultived in bags with 4 dm³ of soil. It was noticed positive answers by seedlings cultivated species for all the biometric characters analyzed and, in the same way, for the contents of almost the analyzed nutrients. For the growth characteristics, 200 kg.ha-1 was the dose that provided the high growth for mohogany, on the interval of 90 days.