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O jacarandá (Dalbergia nigra (Vell.) Allemão ex Benth) é uma espécie da família Leguminosae-Fabaceae, com potencial para diversos usos, incluindo recuperação de áreas degradadas. Neste trabalho, objetivou-se verificar o crescimento das mudas de jacarandá-da-bahia sob diferentes doses dos nutrientes cálcio, magnésio e enxofre, em solos com características diferentes. O experimento foi conduzido em casa de vegetação no período de fevereiro de 2006 a junho de 2006. Os tratamentos foram delimitados segundo uma matriz baconiana, em que se variaram os nutrientes em três doses e dois tratamentos adicionais (zero e referência). Adotou-se o delineamento inteiramente casualizado com quatro repetições, num total de 44 unidades amostrais. As mudas foram conduzidas em vasos plásticos com capacidade para 2,1 dm-3 e colhidas aos 120 dias após a semeadura, sendo avaliadas diversas características morfológicas. A espécie se mostrou, em geral, pouco exigente em relação à aplicação dos nutrientes. Enquanto novos estudos, com doses menores às testadas neste, não sejam feitos, e tomando como base a massa seca total e as condições similares à desse experimento, indicam-se as doses de: 0,8 cmol c dm-3 de solo de Ca e 20 mg dm-3 de solo de S, independente do solo testado; e 0,2 e 0,8 cmol c dm-3 de solo de Mg para solos com características similares ao PVAm e LVAd, respectivamente

Insight of nutrient release patterns associated with the decomposition of plant residues is important for their effective use as a green manure in food production systems. Thus, this study aimed to evaluate the ability of the Century, APSIM and NDICEA simulation models for predicting the decomposition and N mineralization of crop residues in the tropical Atlantic forest biome, Brazil. The simulation models were calibrated based on actual decomposition and N mineralization rates of three types of crop residues with different chemical and biochemical composition. The models were also validated for different pedo-climatic conditions and crop residues conditions. In general, the accuracy of decomposition and N mineralization improved after calibration. Overall RMSE values for the decomposition and N mineralization of the crop materials varied from 7.4 to 64.6% before models calibration compared to 3.7 to 16.3 % after calibration. Therefore, adequate calibration of the models is indispensable for use them under humid tropical conditions. The NDICEA model generally outperformed the other models. However, the decomposition and N mineralization was not very accurate during the first 30 days of incubation, especially for easily decomposable crop residues. An additional model variable may be required to capture initial microbiological growth as affected by the moisture dynamics of the residues, as is the case in surface residues decomposition models.

Neste trabalho, objetivou-se verificar o teor e conteúdo de N, P, K, Ca e Mg, bem como determinar o nível crítico desses nutrientes no solo e na planta. As mudas foram cultivadas, no período de dezembro de 2004 a maio de 2005, em vasos com capacidade para 2,1 dm-3 contendo amostras de solo de três classes (Argissolo Vermelho-Amarelo AVA, Latossolo Vermelho-Amarelo Álico LVA e Latossolo Vermelho-Amarelo Distrófico - LVD). Os tratamentos foram delimitados segundo uma matriz baconiana, onde se variaram os macronutrientes, em três doses, e dois tratamentos adicionais (zero e referência), com quatro repetições. Verificou-se que, em geral, as mudas da espécie absorveram maior quantidade de N, P, K, Ca e Mg, à medida que a disponibilidade destes aumentava no solo. Tal fato refletiu em maior concentração dos nutrientes aplicados em todas as partes da planta. Entretanto, em alguns casos não houve resposta em crescimento correspondente a esse aumento. Os nutrientes que mais proporcionaram efeitos foram o P, o N e o S; poucas respostas foram observadas nos demais nutrientes (Ca, Mg e K). A espécie tem baixo requerimento nutricional, sendo o nível crítico dos nutrientes, no solo e na planta, menores do que os observados em outras espécies florestais. Para o K e o Ca, sugerem-se estudos com doses dentro das faixas de valores encontrados, para melhor definição dos níveis críticos.

Senna macranthera (Fedegoso) tem grande ocorrência natural e potencial para uso em recuperação de áreas degradadas. Dada a grande necessidade de informações sobre a nutrição de espécies florestais a exemplo da citada, avaliou-se a resposta das plantas de Senna macranthera a doses de N, P, K, Ca, Mg e S sobre o crescimento e produção de biomassa, bem como sobre os índices de qualidade de mudas H/D, H/MSPA, MSPA/ MSR e IQD. O trabalho, conduzido em casa de vegetação, utilizou amostras de um Latossolo Vermelho- Amarelo distrófico retiradas da camada abaixo de 20 cm, secas ao ar, peneiradas e caracterizadas quimicamente. Delimitouse o trabalho por meio de uma matriz baconiana, avaliando três doses dos seis macronutrientes e dois tratamentos adicionais, um com doses de referência e outro sem adição de nutrientes. Adotou-se o delineamento inteiramente casualizado com quatro repetições, num total de 80 unidades amostrais. Colhidas as plantas, verificou-se, através da análise dos contrastes ortogonais, resposta significativa aos tratamentos aplicados a todas as variáveis estudadas. Não foi possível determinar a dose crítica para todos os nutrientes em todas as diferentes variáveis analisadas. Verificou-se, também, a necessidade de maior diferenciação entre as doses aplicadas, bem como de adoção de um tratamento-testemunha por nutriente. É interessante aumentar o tempo experimental, tendo em vista o crescimento mais lento observado da espécie, comparativamente a outras já estudadas.Senna macranthera (Fedegoso) has large natural occurrence, with potential use in the recovery of degraded areas. Due the lack of information on the nutrition of this forest species, this work evaluated the response of Senna macranthera to the doses of N, P, K, Ca, Mg and S on the growth and biomass production, and the indexes of quality of seedlings H/D, H/MSPA, MSPA/MSR and IQD. The experiment was carried out in a greenhouse and used samples of a dystrophic red-yellow latosol of the layer bellow 20 cm that were air dried, sieved and chemically characterized. The treatments were delimited according to a Baconian matrix,with three doses of the six macronutrientes and two additional treatments, one with reference doses and other without addition of nutrients. The experiments were arranged in a complete randomized design, with 4 repetitions, in a total of 80 sample units. Plants were collected and the orthogonal contrast analysis showed significant differences for all the treatmens applied to the studied variables. In spite of that, it was not possible to determine the critical nutrient dose for all analyzed variables. It was also verified the need for a greater differentiation among the tested doses, as well as of a control treatment for each studied nutrient. It is also recommended to increase the experimental time because of the slow growth rate of this species compared with others already studied.

Neste trabalho, objetivou-se avaliar, por meio de características morfológicas, o efeito de doses de macronutrientes no crescimento e desenvolvimento de mudas de angico- vermelho (Anadenanthera macrocarpa (Benth.) Brenan) produzidas em amostras de três classes de solo (Argissolo Vermelho-Amarelo, Latossolo Vermelho-Amarelo álico e Latossolo Vermelho-Amarelo distrófico). As mudas foram plantadas em vasos com capacidade para 2,1 dm³. O experimento foi conduzido no período de dezembro de 2004 a maio de 2005. Os tratamentos foram delimitados segundo uma matriz baconiana, em que se variaram os macronutrientes em três doses diferentes, mais dois tratamentos adicionais (zero e base), com quatro repetições. As fontes de N, K e S foram parceladas em quatro vezes (0-30-60-90 dias). Em termos gerais, o maior crescimento das plantas ocorreu no Latossolo Vermelho-Amarelo álico. O nutriente que mais surtiu efeitos significativos foi o P, sendo recomendadas doses de 150 a 250 mg dm-3. Para a aplicação de N, recomendam-se doses mínimas de 50 mg/dm³. A aplicação de S deve ser de 20 a 80 mg dm-3. As respostas à aplicação dos demais nutrientes (Ca, Mg e K), em muitos casos, não ocorreu, evidenciando-se que a espécie tem baixo requerimento por eles. Entretanto, partindo desse estudo, sugerem-se novos estudos com os nutrientes K e Ca, para produção de mudas da referida espécie nesses solos.This work aimed to evaluate, by means of morphological characteristics, the effect of macronutrient doses on the growth of angico vermelho (Anadenanthera macrocarpa (Benth.) Brenan) seedlings cultivated in three soils (Red Yellow Argisol, Red Yellow Dystrophic Latosol and Red Yellow alic Latosol). The seedling were sown in vases with capacity of 2.1 dm³ . The experiment was carried out from December 2004 to June 2005. The treatments were delimited according to a Baconian matrix, with macronutrients varying in three different doses, plus two additional treatments (zero and base), with four repetitions. The sources of N, K and S were applied in four times (0-30-60-90 days). In general, the highest plant growth occurred in the Red Yellow alic Latosol soil. The nutrient presenting the most significant effects was P, with doses of 150- 250 mg dm-3 being recommended. For N, minimum doses of 50 mg/dm³ are recommended. The nutrient S must be applied between 20 and 80 mg dm-3. The responses to the other nutrients (Ca, Mg and K), in many cases did not occur, suggesting that the species has low requirement for them. However, based on this work, further studies are suggested on the nutrients K and Ca, for production of seedlings of the studied species in these soils.

A recomendação de adubação para as culturas agrícolas, no Brasil, é feita com base em tabelas que relacionam a classe de disponibilidade do nutriente no solo com a dose a ser aplicada. Este trabalho apresenta uma alternativa para recomendar corretivos e fertilizantes para a cultura da soja, o SIRSo (sistema de recomendação de corretivos e fertilizantes para a cultura da soja). O princípio desse sistema é o balanço nutricional, ou seja, a recomendação se faz a partir da diferença entre o requerimento de nutrientes pela planta e o suprimento de nutrientes pelo solo, por resíduos orgânicos, por fertilizantes e pela calagem. O sistema considera ainda o fator sustentabilidade, visando manter uma quantidade de nutriente no solo capaz de garantir produtividade mínima em cultivos subseqüentes. Para recomendar calagem, o sistema considera dois métodos: a neutralização do Al3+ e a elevação dos teores de Ca2+ + Mg2+, ou a saturação por bases. O requerimento de nutrientes varia com a produtividade esperada de grãos, com as características do solo e com a taxa de recuperação pela planta do nutriente aplicado ao solo. O suprimento pelo solo depende da disponibilidade do nutriente, estimada a partir da análise de solo e da taxa de recuperação pelo extrator do nutriente aplicado. As comparações entre as recomendações geradas pelo SIRSo e aquelas oriundas das tabelas em uso no País mostram, em geral, que o SIRSo recomenda maior quantidade de nutrientes, principalmente de P e K quando consideradas as maiores produtividades, fato confirmado pela análise de sensibilidade, que mostrou grande variação da dose a ser recomendada desses nutrientes com a produtividade de grãos. Esse fato pode ser considerado como vantagem do SIRSo em relação às tabelas, muitas das quais apresentam pouca ou nenhuma variabilidade das doses em relação à produtividade.Fertilizer recommendations for agricultural crops in Brazil are based on tables that relate indexes of nutrient availability in the soil with the required dose of the nutrient. This study presents an alternative for lime and fertilizer recommendations for soybean, called SIRSo. This lime and fertilizer recommendation system for soybean considers the nutritional balance, i.e., recommendations are based on the difference between plant nutrient requirement and the nutrient supply from the soil through organic residues, fertilizers and liming. The system further takes a sustainability factor into consideration, aiming at the maintenance of soil nutrient levels that ensure a desired minimum yield in subsequent cultivations. The system considers two methods for liming recommendations: Al3+ neutralization and increased Ca2+ + Mg2+ contents or base saturation. Nutrient requirements vary according to the expected grain yield, the soil characteristics and plant recovery rate of the nutrient applied to the soil. The soil supply depends on the estimated nutrient availability based on the soil analysis, and on the recovery rate of the applied nutrient by the extractor. Comparisons of SIRSo-based recommendations with those of the tables used nationwide show that SIRSo generally recommends higher nutrient quantities, mainly for P and K, when the highest yields are considered. This fact was confirmed by the sensitivity analysis, which detected wide variation of the recommended dose for these nutrients according to the grain yield. This fact is considered an advantage of SIRSo over the tables, where recommendations of doses according to the yield are little or not adjustable at all.

Potassium is present in distinct forms in the soil. The K forms in the soil are characterized by reversible exchanges between compartments and they have different characteristics in regards to availability for plant uptake. The soil's capacity to supply or restrict K to plants is different for each soil and it determines the sustainability of agricultural production and fertilization management. Thus, the goal of this study was to evaluate the K supplying capacity of soils of different mineralogies from Minas Gerais (Brazil), under successive corn cultivation. A greenhouse experiment was carried out in factorial 7 x 6 (seven soils and six rates of K), in a randomized complete block design, with four replications. The corn plants were cultivated during 45 days for seven successive crop cycles in pots. The potassium availability in the soil was evaluated at the beginning and at the end of each crop cycle using Mehlich-1 and Mehlich-3 extractors. All treatments showed significant decreases in soil K content, which affected corn dry matter accumulation. The reserve of K was highest in Ultisols followed by Inceptisols and Oxisols. Contribution of non-exchangeable potassium to the plant nutrition was observed. The K availability in soil measured by Mehlich-1 represented 40% of K uptake by plants, and 61% of K uptake when Mehlich-3 was used.El potasio está presente en diferentes formas en el suelo, con distinta accesibilidad para las plantas pero con reversibilidad entre ellas. La capacidad de los suelos en la aportación de K para las plantas es diferente y determinante en la sustentabilidad de la producción agrícola y en el manejo de la fertilización con este nutriente. El objetivo de este trabajo fue determinar la capacidad de aportación de K de suelos del Estado de Minas Gerais (Brasil), con diferente mineralogía, en cultivos sucesivos de maíz. El experimento, con un esquema factorial 7 × 6 (siete suelos y seis dosis de K), fue llevado a cabo en invernadero en bloques al azar, con cuatro repeticiones, durante siete cultivos sucesivos. En cada cultivo las plantas fueron cosechadas a los 45 días de su emergencia. La disponibilidad de K para las plantas fue determinada al inicio y entre cada cultivo con los extractores Mehlich-1 y Mehlich-3. Se verificó una expresiva reducción de las concentraciones de K en los suelos, comprometiendo la producción de materia seca de las plantas de maíz en todos los suelos estudiados. La reserva de K fue mayor en los Ultisoles, seguidos de los Inceptisoles y de los Oxisoles. Se observó la participación de formas no intercambiables de K en la nutrición de maíz. La disponibilidad de K del suelo determinada con el extractor Mehlich-1 representó el 40% del K absorbido por las plantas y el 61% del K absorbido cuando se utilizó el extractor Mehlich-3.O potássio está presente em diferentes formas no solo, diferindo na acessibilidade para as plantas e com reversibilidade entre essas formas. A capacidade dos solos no suprimento de K para as plantas é diferenciada e determinante na sustentabilidade da produção agrícola e no manejo da fertilização com este nutriente. Assim, neste trabalho objetivou-se avaliar a capacidade de suprimento de K por solos do Estado de Minas Gerais (Brasil) de diferentes mineralogias, em cultivo sucessivo de milho. O experimento foi conduzido em casa de vegetação, num esquema fatorial 7 x 6 (sete solos e seis doses de K), sendo as unidades experimentais distribuídas em blocos casualizados, com quatro repetições, por sete cultivos sucessivos. As plantas eram colhidas após 45 d para cada cultivo. A disponibilidade de K para as plantas foi avaliada no início e no intervalo de cada cultivo, usando os extratores Mehlich-1 e Mehlich-3. Verificou-se expressiva redução dos teores de K no solo, comprometendo a produção de matéria seca do milho em todos os solos estudados. A reserva de K foi maior nos Argissolos, seguido dos Cambissolos e Latossolos. Houve participação de formas não trocáveis de K na nutrição do milho. A disponibilidade de K no solo avaliada pelo extrator Mehlich-1 representou 40% do K absorvido pelas plantas e, 61% do K absorvido quando utilizou-se o extrator Mehlich-3.

Many ecosystems are being severely degraded, leading the United Nations to deem 2021–2030 as the Decade on Ecosystem Restoration. To be successful, this effort requires robust monitoring tools to assess land reclamation practices. This study aimed to evaluate the quality of recovery efforts in mined areas by developing a Recovery Quality Index (RQI) based on soil and vegetation indicators. Using the heavily mined Iron Quadrangle region of Brazil as an example, four undisturbed reference areas were selected: Atlantic Forest; ferruginous rupestrian grassland with dense vegetation; ferruginous rupestrian grassland with sparse vegetation; and quartzite rupestrian grassland. Four areas directly or indirectly affected by mining were selected, including an environmental compensation area set aside 5 years prior to the study, two sterile piles that had undergone recovery for 15 and 20 years, and a cave area with 15 years of recovery. Two vegetation parameters and 34 soil attributes were used in a Principal Component Analysis (PCA) to select indicators and scores. Vegetative parameters had the lowest RQI weights. Soil physical indicators tended to be the most important. RQI values were lowest when Atlantic Forest was used as the reference, showing that the forest was a unique ecosystem, and the cave site had lower RQI scores than the other restored sites, indicating the high degree of disturbance that occurred in that low-lying area. The oldest sterile pile tended to have higher RQI values than the newest and similar values to the less disturbed compensation areas. The recovery quality index values were similar in all areas, with 5 to 20 years in the recovery process, showing that the rehabilitation process is slow in this environment.

ABSTRACT Compaction caused by mechanization affects soil quality and, consequently, the development of crops. This study aimed to evaluate the effect of different degrees of soil compaction on the physiology, morphology, and anatomy of different coffee cultivars in a controlled environment. The experiment was carried out in a greenhouse, with randomized block design in a 5 × 5 factorial arrangement, with five coffee cultivars (Arara, Catuaí Amarelo IAC 62, Catuaí Vermelho 144, MGS Paraíso 2 and Mundo Novo IAC 379-19) and five degrees of compaction (68, 74, 80, 86 and 92 %), with four repetitions, totaling 100 experimental units. The following variables were evaluated in the aboveground biomass: plant height, number of leaves, diameter of the orthotropic branch, fresh mass of leaves and stem, leaf area, gas exchange, and chlorophyll a and b index; in the roots: length, surface area, volume, diameter of fine and coarse roots, fresh and dry mass of roots, as well as anatomical characteristics. Results showed that soil with degrees of compaction above 80 % negatively affected the variables evaluated. Catuaí Vermelho 144 presented the worst performance regardless of the degree of compaction, while Arara and MGS Paraíso 2 showed the best performance under the evaluated compaction degrees. Anatomical structure of the roots was modified with soil compaction, and no differences were observed among cultivars.

ABSTRACT Large-scale mining operations, such as those associated with iron extraction, disturb soils and vegetation and create the need for effective rehabilitation practices. The Iron Quadrangle region of southeastern Brazil is one of the world’s biodiversity hotspots; however, iron mining activities threaten many natural and seminatural ecosystem types in which many rare/protected species occur. The Iron Quadrangle has four main ecosystem types: Atlantic Forest (AF), ferruginous rupestrian grassland with dense vegetation (FRG-D); ferruginous rupestrian grassland with sparse vegetation (FRG-S); and quartzite rupestrian grassland (QRG). To support rehabilitation and monitoring plans, we evaluated reference areas and identified soil and vegetative attributes that best differentiated between these four ecosystems. We measured thirty-four physical, chemical, and biological soil properties and two vegetation parameters and, using a multivariate analysis, detected: 1) correlations between properties and 2) differences between areas. We identified twelve properties that best differentiated the areas (in order from most to least relevant): nickel content; exchangeable aluminum; clay content; above-ground vegetation volume; aluminum saturation; particle density; bulk density; arsenic content; zinc content; lead content, fine sand plus silt content; and fine sand content. Soil physicochemical properties proved to be more sensitive to differences in ecosystem type, and in particular, parameters related to fertility and the presence of metals and semi-metals differentiated the AF from the FRG-D and FRG-S. Soil physical properties, including fine sand and silt content, were most important for differentiating QRG from the other ecosystems, possibly resulting from the exposure of quartzite material to erosive processes. This study demonstrates the importance of identifying appropriate reference areas for post-mining reclamation.

ABSTRACT Reference values of leaf nutrient contents are essential for nutritional assessment of plants. The objective was to establish nutritional reference values for ‘BRS Platina’ banana in improved fertility soil, using the sufficiency range (SR), border Line (BL) and mathematical chance (MCh) methods, in addition to the critical level obtained by the reduced normal distribution (CLz). The study was carried out in Guanambi-BA, considering nutrient contents and yields of an experiment arranged in randomized blocks, 5 x 6 factorial scheme, with five doses of K2O (0, 200, 400, 600 and 800 kg ha-1) supplied with fertilizers for organic management and six sampling times (210; 390; 570; 750; 930 and 1,110 days after planting), totaling 90 plots. Plots with high yield, ≥ 38.40 t ha-1, formed the reference population and plots with yield ≥ 47.43 t ha-1 formed the reference subpopulation. There was convergence between the optimal values obtained by the methods evaluated. Therefore, the reference values adjusted by the SR, BL, MCh and CLz methods can be used with assertiveness to interpret the foliar analysis of the ‘BRS Platina’ banana in improved fertility soils. Furthermore, among these, MCh stands out as it provides narrower optimal ranges.

Knowing the accumulation of nutrients in mango plants is essential for calibrating fertilization programs aiming to increase yield in nutritionally unbalanced orchards. The work aimed to evaluate mango nutritional efficiency through nutrient accumulation and partitioning in plants of Palmer cultivar grown in sand soils at São Francisco Valley, Northwest Brazil. Commercial orchards located in Bahia and Pernambuco States, Brazil, under semi-arid climate (BShw; 400-800 mm annual rainfall) had the vegetable biomass and nutrient contents in the mango compartments determined in 1, 2, 4, 7, and 12 years old plants, by evaluating four plants of each age from 20 sample units. The separated samples of the harvested trees originated the compartments roots, stems, thick twigs, thin twigs, leaves and fruits. Nutrient contents and plant dry matter per compartment were determined and plant nutrient accumulation evaluated. Biomass and fruits coefficient of biological utilization were calculated. There was increment in the accumulated content of macronutrients in the mango plants over the years, with superiority for N and K, for which there was a sharp increase as compared to the other macronutrients. Manganese and Fe were the most accumulated micronutrients in the plants over the years. The canopy of the mango Palmer plants is the compartment that accumulates more macro and micronutrients, and the partition within the canopy occurs in the sequence: leaf> thin twig> thick twig. Phosphorus and Mg, and Cu and B are the nutrients more efficient to generate plant biomass and fruit production in the mango Palmer orchards.

Abstract Adequate plant nutrition is essential to attain higher yields. The objective was to determine potential-nutrient response curves and sufficiency ranges using the boundary line approach and balance indices of Kenworthy for interpreting the nutritional status of ‘Grand Nain’ banana cultivated in two environments. The study was carried out using a database containing leaf nutrient concentrations and yields of bananas cultivated on two areas located in Missão Velha-CE, and Ponto Novo-BA, Brazil. Plots with high-yielding plants, which were those with yields above average plus 0.5 standard deviation, were used atem as reference population. The database was subdivided into two sets. One of them contained 46 leaf tissue samples and reference population with yield greater than 58.84 Mg ha-1 year-1, in Missão Velha-CE. The second data set contained 19 samples and reference population with yield greater than 76.12 Mg ha-1 year-1 in Ponto Novo-BA. Potential response curves were fitted to the relationship between relative yield and leaf element concentrations and balance indices of Kenworthy. Models expressed high predictive power. Sufficiency ranges for macro- and micronutrient concentrations and balance indices of Kenworthy were established. The ranges allow an improved nutritional status assessment of irrigated ‘Grand Nain’ bananas.

ABSTRACT: Proper plant nutrition is critical to increasing the yield of bananas. The objective was to establish the potential nutrient-response curves and sufficiency ranges using the boundary line approach (BLA) and the method proposed by Kenworthy (MK) to assess the nutritional status of ‘Prata-Anã’ bananas cultivated under two environmental conditions. The study was carried out using a database comprising leaf nutrient concentrations and banana yields grown at Missão Velha, Ceará, and Ponto Novo, Bahia, Brazil. The reference population consisted of high-yielding plants with yields greater than the mean yield plus 0.5 standard deviation. The database was divided into two datasets. One contained 253 leaf analysis results and a reference population with a mean yield greater than 39.81 t ha−1 yr−1 at Missão Velha. The other contained 147 samples and a reference population with a mean yield greater than 41.69 t ha−1 yr−1 at Ponto Novo. The sufficiency ranges obtained by the BLA for ‘Prata-Anã’ banana in Bahia and Ceará, respectively, are: a) for macronutrients (g kg−1): N (19.3-22.0) and (19.9-22.1); P (1.4-2.0) and (1.4-1.6); K (22.6-32.2) and (24.0-31.3); Ca (4.6-6.5) and (5.3-5.8); Mg (1.8-2.6) and (2.1-2.7); S (1.3-2.0) and (1.3-1.5); b) for micronutrients (mg kg−1): B (8.4-13.0) and (13.7-16.4); Cu (5.6-8.4) and (4.4-5.2); Fe (54.2-77.6) and (39.0-55.0); Mn (140.1-222.8) and (64.0-91.0); Zn (13.5-18.3) and (12.4-14.5). The sufficiency ranges obtained by the BLA are more assertive when assessing the nutritional status for ‘Prata-Anã’ banana.

ABSTRACT: The chemical analysis of flowers has been studied for some crops. In coffee trees, the flower tissue analysis could anticipate the nutritional diagnosis. This study aimed to: (i) compare the mineral composition of coffee flowers and leaves; and to (ii) generate reference values for nutritional diagnosis of coffee trees, based on flower and leaf analysis. Nutrient content of flowers and leaves and coffee productivity were evaluated in 26 commercial farms located in Manhuaçu, MG, Brazil throughout three years. The critical nutrient content range in flowers are respectively: 2.78 - 3.17, 0.23 - 0.28, 2.80 - 3.12, 0.30 - 0.37, 0.24 - 0.30, 0.15 - 0.18 dag kg-1 of N, P, K, Ca, Mg, and S; and 17 - 21, 12 - 18, 52 - 80, 26 - 43, and 28 - 48 mg kg-1 of Zn, Cu, Mn, Fe, and B. For leaves, the critical nutrient ranges are respectively: 2.63 - 2.86, 0.13 - 0.14, 2.13 - 2.33, 1.04 - 1.22, 0.27 - 0.33, 0.15 - 0.18 dag kg-1 of N, P, K, Ca, Mg, and S; and 9 - 14, 15 - 23, 80 - 115, 99 - 148, and 31 - 37 mg kg-1 of Zn, Cu, Mn, Fe, and B. The nutritional diagnosis of coffee trees for N, P, Ca, Fe, Cu, and Mn can be anticipated using flower analysis.

ABSTRACT Tissue analysis results are interpreted by comparing them with nutrient standards; however, using universal standards may lead to a misleading nutritional diagnosis. This study aimed to evaluate the degree of universality of Kenworthy and DRIS norms for irrigated ‘Prata-Anã’ (AAB) and ‘Grande Naine’ (AAA) banana plants grown in two environments. The study was carried out using a database containing leaf nutrient contents and yield data of two farms located in Ponto Novo, Bahia State, and Missão Velha, Ceará State, Brazil. A reference population was that with yields above the average yield plus 0.5 standard deviation. Using a reference population, the mean, standard deviation, and coefficient of variation of nutrient content and dual nutrient ratios were calculated for each site × cultivar combination. To verify the homogeneity of variance among populations, F-test was used (p≤0.05). Means were compared using t-test (p≤0.05). Differences in climate and soil at each farm explain the high frequency of significant differences found between norms for each site. Kenworthy norms established for interpreting leaf nutrient contents of P, K, Ca, Mg, S, Cu, Fe, Mn, and Zn for ‘Prata-Anã’ grown in Ceará were higher than those in Bahia, while for N and B contents, the norms were higher in Bahia. This is due to differences in soil fertility and alkalinity affecting nutrient availability as well as non-nutritional factors. Kenworthy and DRIS norms for ‘Prata-Anã’ and ‘Grande Naine’ bananas grown in Ceará have higher variability and are greater than for those grown in Bahia. Norms are less convergent for ‘Prata-Anã’ than ‘Grande Naine’. Site- and cultivar-specific norms are recommended over universal ones for assessing the nutritional status of ‘Prata-Anã’ and ‘Grande Naine’ banana plants cultivated in different environments.

Cationic micronutrients bioavailability depends on the chemical characteristics of soil fractions. Fourteen soils received individual doses of five micronutrients (Cu, Fe, Mn, Zn, B) arranged in seven treatments set according a Baconian Matrix. The soils incubated with treatments during 15 days had corn cultivated in greenhouse for 30 days, in three consecutive growth cycles. The cationic micronutrients were determined in the corn shoots after each growth cycle. Soil samples collected before the first and after each growth cycle had the available concentrations of Cu, Fe, Mn and Zn determined by single extractions (Mehlich-1 and DTPA-pH 7.3) and by sequential extraction. Correlation analysis was performed for the Cu, Fe, Mn and Zn concentrations determined in the corn shoots, the available concentrations of Cu, Fe, Mn and Zn in the soils (Mehlich-1 and DTPA) and the concentrations of Cu, Fe, Mn and Zn in the soil fractions (sequential extraction). The distribution of available metals forms in fractions reflected their affinity with soil components. Soil available Cu correlated with Cu bound to organic matter. The exchangeable fraction was the main source of soil available Mn and Zn. The Fe availability related mainly to the Mn oxides, Fe oxides, and exchangeable fractions. The plants absorbed Cu mainly from the Mn-oxides and organic matter fractions. Manganese absorbed by plants originated from the exchangeable and Mn-oxides fractions. The Zn absorbed by plants originated mainly from the exchangeable fraction. Correlations of single metal extractions (Mehlich-1 and DTPA) with Cu, Mn and Zn contents in plants were positive.

ABSTRACT: Litter decomposition dynamics and nutrient release are also dependent on their biochemical composition, and such information is important for adequate nutritional management but is still incipient for plants like teak. This study aimed to evaluate the decomposition dynamics, nutrient release, and biochemical composition of clonal teak litter. The study was conducted in areas of clonal teak stands, in São José do Rio Claro, Mato Grosso, Brazil. Litter collectors were arranged in the area to collect material along the entire dry period. Subsequently, this litter was placed in litter bags, which were distributed in the area. The litter bags were collected every month, for 0.91 years, to determine the dry matter and mineral nutrient contents, in order to estimate the decomposition and nutrient release. Litter biochemical composition was determined at the times of 0, 0.25, 0.58, 0.75, and 0.91 years. Teak litter, essentially leaves, had a half-life time (t1/2) of dry matter and C of 0.74 years, due to the high content of insoluble lignin, which corresponds to 2.28 Mg ha-1 of dry matter and 1.2 Mg ha-1 of C. The t1/2 values of N and P release (1.20 and 1.01 years) were higher than those of K, Ca, and Mg (0.08, 0.47, and 0.66 years, respectively). Hence, the nutrient release rate of the litter followed the descending order: K > Ca > Mg > P > N. The litter biochemical composition at the end of the experimental period showed reductions of 18.7 % in polysaccharides and holocellulose, 56 % in polyphenols, 56.3 % in tannins, 22.2 % in extractives, and 28.5 % in soluble lignin; and increases of 25.6 % in insoluble lignin and 22.6 % in total lignin. These data are useful for the balance of carbon and mineral nutrients and to support fertilization management in teak plantations in low-fertility soils.

ABSTRACT The optimal soil pH for most annual crops in Brazil varies between 5.7 and 6.0. Numerous methods have been developed for estimating lime requirement (LR), but they vary widely in their predictions and fail to raise pH to desired values for optimum crop production in the highly weathered soils of Brazil. The objectives of this study were to (i) compare seven traditional methods for estimating LR in Brazilian soils; (ii) assess the effects of LR predicted by these methods on soil-acidity related properties, and (iii) determine if these methods are predicting LR to attain target pH values of 5.8 and 6.0, which are within the pH range recommended to optimize crop yields. The traditional LR methods evaluated in this study are based on the following criteria: exchangeable acidity (EA), base saturation (BSAT), exchangeable acidity along with Ca2+ and Mg2+ as proposed by the 4th (MG4A) and 5th (MG5A) Approximations to the Minas Gerais State, SMP soil-buffer pH (SMP), potential acidity (PA), and soil pH along with organic matter (pHOM). These methods were compared with the standard incubation method using correlation-regression analysis and, alternatively, the identity test designed for assessing equivalence between methods. Representative agricultural soils (n = 22) were incubated for 60 days with incremental amounts of lime determined by the tested methods. On average, LR predictions differed among methods, and increased in the following order: EA < BSAT ≈ MG5A ≤ MG4A ≈ SMP ≤ PA < pHOM. Suitable changes in soil pH, exchangeable acidity, potential acidity, base saturation, and Ca2+ and Mg2+ were achieved upon application of LR estimated by all methods except the EA and pHMO, which resulted in undesirable soil acidity characteristics. All methods evaluated in this study were unable to predict LR for attaining target pH values of 5.8 and 6.0 as revealed by the identity test, even though they were moderate to strongly correlated with the standard incubation method as indicated by the correlation-regression analysis. Further research should focus on the development of reliable methods for predicting LR to attain desired pH values and consequently maximize crop production on Brazilian soils.

ABSTRACT In Brazil, empirical models are traditionally used to determine lime requirement (LR), but their reliability is doubtful in most cases, since they can lead to under- or overestimation of LR for different soil types. In this study, the most critical characteristics influencing LR were selected to develop reliable models for predicting LR that raise soil pH to optimum values for crop production in Brazil. Soil samples (n = 22) with varying proportions of clay (5-88 %) and organic matter (OM) levels (3.78-79.35 g kg-1) were used to develop the models. Organic matter and potential acidity (HAl) combined with ΔpH [target pH(H2O) - initial pH(H2O)] were the best predictor variables for estimating LR. Four models were developed (OMpH5.8, OMpH6.0, HAlpH5.8, and HAlpH6.0) for estimating LR to attain target pH values of 5.8 or 6.0 with reasonably high prediction performance (0.758≤ R2 ≤0.886). An algorithm was further developed for selecting the LR to be recommended among those estimated by the models. The proposed algorithm enables to select the minimum LR that ensure the adequate supply of Ca and Mg to plants and does not exceed the levels of soil HAl, thus preventing excessive pH increase. The new predictive models were less sensitive to predict LR high enough to meet Ca2+ and Mg2+ requirements of plants in soils containing levels of HAl lower than 5 cmolc dm-3 and OM lower than 40 g kg-1. However, they ensured an adequate supply of Ca2+ and Mg2+ to plants and avoided the overestimation of LR for most soils used in this research. Validation via an independent dataset (n = 100 samples) confirmed the good predictive performance of the models across a wide range of soil types. In summary, the proposed models can be used as good alternatives to traditional methods for predicting LR for a great variety of Brazilian soils. Further, they are versatile and may be easily deployed in soil testing laboratories, since soil pH, OM, and HAl are characteristics determined in routine analysis.

O plantio direto é uma técnica tradicionalmente adotada no Brasil. Um dos avanços neste sistema é sua realização de forma orgânica, linha de trabalho ainda pouco pesquisada e de resultados pouco conhecidos. Assim, realizou-se este estudo com o objetivo de determinar alguns atributos químicos e físicos de um Argissolo Vermelho-Amarelo sob plantio direto diferentemente manejado. O delineamento estatístico adotado foi blocos casualizados, com três repetições, em esquema fatorial 3 x 2 compreendendo três áreas: plantio direto (PD), plantio direto orgânico (PDO) e mata nativa (MN), e duas profundidades de amostragem do solo (0-20 e 20-40 cm). As amostras de solo foram coletadas para a determinação dos atributos químicos [pH em água, teores de matéria orgânica do solo (MOS) e de Zn, Cu, Mn, Fe, B] e físicos [densidade do solo (DS), argila dispersa em água (ADA), grau de floculação (GF), umidade na capacidade de campo (CC) e no ponto de murcha permanente (PMP), capacidade de água disponível (CAD) e classe textural]. Os atributos químicos avaliados, com exceção do Zn (0-20 cm), apresentaram comportamento similar para as áreas de PD e PDO, independente da profundidade amostrada. O sistema plantio direto favoreceu a manutenção do teor de MOS, sendo equivalente à MN. Com relação às condições físicas, os sistemas PD e PDO preservaram a DS de modo similar à MN, não havendo compactação nestas áreas. Tais sistemas apresentaram maior disponibilidade de água para as plantas em comparação a área preservada, nas duas profundidades.

The Non-Destructive Sampling (NDS) provides an efficient, simple and safe characterization of chemical properties of the plant, as the Coefficient of Biological Use (CBU). The association of NDS with the technique of Artificial Neural Networks (ANN) can be a potential alternative to replace the regression equations and the traditional methods of interpolation. Therefore, this work aimed to evaluate the efficiency of ANN and non-destructive sampling for the efficiency of nutrient use in the trunk. The research plot was installed in a randomized block being studied, in three blocks, the effect of five planting spacing: T1-3,0m x 0,5 m, T2 - 3,0 m x 1,0 m, T3 - 3,0 m x 1,5 m, T4 - 3,0 m x 2,0 m e T5 - 3,0 m x 3,0 m. A sample-tree was felled to make the cubage and quantify the dry bark and wood per experimental plot, totaling 15 trees. The sample-trees were weighed in the field and subsamples of bark and wood were collected along the stem to form a composite sample per tree. Also removed was a single sample of each component obtained with the aid of a chisel and hammer in DBH in the same sample-trees. The samples were dried at 65°C until constant weight. The material was ground and subjected chemical analysis. Adjusted regression models and application of ANN to estimation of CBUTrunk from the CBUDBH Bark and CBUDBH Wood. The ANN had a higher accuracy and reliability of the regression. Modeling by artificial neural networks using only sample in the DBH region proved to be adequate for estimating the coefficient of biological use of stem.

ABSTRACT Forest cover in areas degraded by mining is an alternative way of mitigating CO2 concentrations in the atmosphere by fixing C in tree biomass. This study evaluated the growth and C stocks of forest cover in an area of bauxite mining with four sources of fertilizer. Height (Ht), diameter at ground level (DGL), and diameter at breast height (DBH) were determined in Anadenanthera peregrina (Ap), clonal Eucalyptus (Euc), and a mixed plantation of 16 native forest species (Nat) at 6, 18, 36, and 56 months of age. Trunk+bark volume, biomass, and C stock were also determined for these forest covers at 56 months of age. The fertilization treatments were a standard (SF) adopted by the company, SF plus organic fertilizer (OF), chemical fertilizer (CF), and OF+CF. Euc displayed greater values of Ht, DGL, and DBH under OF+CF and OF. Fertilization did not influence the Ht and DBH of Ap, but DGL was higher under OF+CF at 36 months compared to SF. The Ht values of Nat were influenced by fertilization at 18 months, with the lowest values under SF. The fertilization influenced the DGL of Nat at 36 and 56 months, which did not occur with DBH. The pioneer species had higher Ht, DGL, and DGB compared to non-pioneer species, regardless of the type of fertilization studied. Fertilization influenced the Ht and DGL of pioneer species at 18 and 36 months of age and only the Ht of non-pioneer species. The estimates of Euc biomass (255 Mg ha-1) and C stocks (120 Mg ha-1) under OF+OC were four times greater than in Ap and Nat, which showed no difference between themselves or the types of fertilization. The growth and estimates of volume, biomass, and C stocks of the forest cover were comparable to those of unmined areas. Euc had the greatest growth, biomass, and C stocks.

Abstract: The objective of this work was to evaluate the effects of the split and combinated application of foliar zinc (ZnF) + soil Zn (ZnS) on Zn concentration in the grains (ZnCG) of common bean (Phaseolus vulgaris). Two experiments were carried out in a greenhouse during two seasons. In the first experiment, two common bean cultivars received six ZnF rates (0, 120, 240, 480, 720, or 1,200 g ha-1), with split applications at the R5, R7, and R8, or R7 and R8, or R8 plant stages. In the second experiment, one cultivar received three ZnS rates (0, 5, or 10 kg ha-1) combined with ZnF rates (0, 1, 1.5, 3, 6, or 10 kg ha-1). In the first experiment, with the ZnF increment, ZnCG increased linearly from 15.3 to 20.7 mg kg-1. ZnF splitting did not affect ZnCG. In the second experiment, ZnF without ZnS did not affect ZnCG. ZnS doubled ZnCG in comparison with the treatment without ZnS application. At 5 kg ha-1 ZnS, the highest ZnCG (67.5 mg kg-1) was obtained with 7.8 kg ha-1 ZnF. At 10 kg ha-1, the highest ZnCG (66 mg kg-1) was obtained with 4.9 kg ha-1 ZnF. ZnF splitting is not advantageous over a single application, and the combination of ZnF and ZnS increases ZnCG in common bean, in greenhouse conditions.

Successive harvesting of leaves (FO) and thin branches (GF), with no nutrient reposition by fertilization, have been resulting in continuous decrease in Brazilian productivity of mate in the last 20 years. So, the objective of this work was to evaluate the influence of harvest interval and phosphate nutrition on the availability of phosphorus (P) in the soil, on the productivity, as well as on the nutritional status of mate plants. The experiment was conducted in São Mateus do Sul/PR, in an Oxisol, where doses of 0, 20, 40, 80, 160 and 320 kg ha -1 of P 2 O 5 were evaluated for harvest intervals of 12, 18 and 24-months in a seven-year- old mate plantation. Soil P availability, at 0-10, 10-20 and 20-40 cm depth, was assessed. Harvest consisted on removal of approximately 95 % of the tree canopy formed since the previous harvest. Harvested green material was individually determined for FO, GF and thick branches (GG), where FO + GF corresponded to the commercial mate (ECOM). The relationship between green/dry mass (MV/MS) was also evaluated for all plant components, as well as the content of P in FO, GF and GG. Phosphate fertilization increased the availability of P in the upper soil layer and the plant responded positively to P application by increasing the dry mass of all the assessed components. Harvests with longer intervals resulted in greater productivity of ECOM, but for maximizing productivity, high doses of fertilizers are needed. Twelve month intervals are insufficient to allow the plant to recover from the harvest impact, even if well-nourished in phosphorus.

The aim of this study was to evaluate the productivity of ministumps and the rooting of minicuttings from hybrid clones of Eucalyptus globulus in response to nitrogen concentrations in nutritive solution, in a fertirrigation system. To do so, we used five clones, namely: two of Eucalyptus urophylla x Eucalyptus globulus (C-04 and C-16); two of Eucalyptus grandis x Eucalyptus globulus (C-26 and C-30) and one of Eucalyptus urophylla x Eucalyptus grandis (1213) as a comparator. Five N concentrations were tested (36, 72, 109, 164 and 218 mg L-1) in a statistical design of randomized blocks on a split plot arrangement with three replications. Six months after the implementation, using standard nutritive solution, in fertirrigation system, the treatment application began. After 30 days, it began the weekly harvest of minicuttings and the cutting plantion at every 15 days, during 90 days. It was evaluated the survival and the productivity of the ministumps and, regarding the minicuttings, it was observed: the survival, the rooting percentage, the minicutting percentage with visible roots at the lower end of the tube, having these 10cm, after 30 days in the greenhouse. It was found that there is a significant effect of N concentration over the monthly productivity of ministumps from clones C-16 (169.05 mg L-1), C-26 (146.67 mg L-1) and for C-04 and 1213, (positive linear effect). However, no significant effect of dose was observed for the percentage of visible roots at the lower end of the tube, rooting and survival of cuttings at thirty days in the greenhouse.

RESUMO Com o presente trabalho objetivou-se avaliar, através dos métodos linha de fronteira e chance matemática, o estado nutricional de pitaias submetidas a combinações de doses crescentes de nitrogênio-potássio (N-K) e fósforo-zinco (P-Zn). Foram aplicadas cinco doses de N (0; 150; 300; 450 e 600 mg dm-3) e K (0; 75; 150; 225 e 300 mg dm-3) no experimento I, e cinco doses de P (0; 75; 150; 255 e 300 mg dm-3) e Zn (0; 2; 4; 6 e 8 mg dm-3) no experimento II. Ambos os experimentos foram arranjados em esquema fatorial 5 x 5, com quatro blocos ao acaso. Houve bastante similaridade entre as faixas de suficiência obtidas pela chance matemática e linha de fronteira, exceto para o fósforo. As faixas de suficiência obtidas pela linha de fronteira foram mais amplas que as obtidas pela chance matemática. O método linha de fronteira apresenta elevada capacidade preditiva no ajuste dos dados, demonstrando ser uma importante ferramenta na obtenção de faixas de suficiência e valores de referência para estudos posteriores de diagnose nutricional em pitaia.

Abstract: Phosphorus is one of the most important nutrients for soybeans, but it presents a complex dynamic in the soil and can become unavailable. The split and localized application of this nutrient can be an effective approach to increase its availability. The aim of this study was to evaluate the effect of a split phosphorus dose applied to the soil and the seed coating with monobasic sodium phosphate on nodulation, growth and yield components of soybean cultivar BRS Valiosa RR. The experiment was conducted in a greenhouse in a completely randomized design in a 2x5x3 factorial arrangement, i.e., coating or not the seeds; five doses of phosphorus applied to the soil; and three times of splitting phosphate fertilizer. Phosphorus content in the index leaf (IL), dry matter of shoots, roots and nodules, yield components, and plant height were evaluated. There was an increase in nodulation and growth of plants with increased levels of phosphorus applied to the soil. In smaller doses, the seed coating and the splitting of phosphorus fertilizer increased nodulation, growth and yield components of plants. Thus, the splitting of the phosphorus dose, combined with seed coating, is indicated for increasing the yield components of soybean plants.

ABSTRACT: In banana cultivation, fertilization recommendations are almost exclusively based on soil chemical analysis, without considering leaf analysis and expected yield, which can help in the adjustment of fertilization programs. The aim of this study was to develop a method to recommend macronutrient fertilization rates which integrates data on leaf analysis, soil chemical analysis, and yield. Yield, soil chemical analysis, and leaf analysis data of fertigated plantations of ‘Prata’ banana were obtained for the first and second halves of the years from 2010 to 2015. Yield was correlated with soil organic matter (SOM) and soil contents of macronutrients (P, K, Ca, and Mg) to obtain the critical level (CLNui). Then, leaf nutrient contents were plotted on a dispersion graph as a function of soil contents using the method of Quadrant Diagram of the Plant-Soil Relationship (QDpsR). Based on leaf analysis, recommended rates were simulated for four plots and compared with rates recommended by other methods. The values of CLNui obtained were 13.2 g dm−3for SOM; 97.5 and 91.5 mg dm−3for P and K; and 2.71 and 0.61 cmolc dm−3for Ca2+and Mg2+. The rates recommended based on leaf analysis diverged from the recommendations of Ferticalc®-Bananeira and the Recommendation Table for Banana Fertilization; in plots for which recommendations were made, there were higher rates of P2O5 and Ca and lower rates of K2O. However, in most cases, applications were not recommended, either because contents in leaves and soil were adequate or because yield was being limited by non-nutritional factors or, if nutritional, related to other nutrient(s). Leaf analysis satisfactorily adjusts the recommended rates of nutrients and has advantages if incorporated in nutritional balance models.

ABSTRACT The use of trees in integrated crop-livestock-forestry systems (ICLF) allows diversifying production, increasing profitability per area, and providing a higher animal comfort. However, the influence of tree component on soil chemical attributes in this system is still little studied. This study aimed to assess the effect of trees and sun-exposed faces to solar radiation on soil nutrient availability at different distances of tree rows in an integrated crop-livestock-forestry system. This study was carried out in the northern Mato Grosso State, Brazil, in the Cerrado - Amazon Forest transition region in an ICLF with the tree component formed by three eucalyptus rows. The assessment carried out in the second year of ICLF implantation considered the effect of tree distances (3, 6, 10, and 15 m) on two sun-exposed faces to solar radiation (north and south) on the main soil chemical attributes. Soil sampling was performed at depths of 0-0.05, 0.05-0.10, 0.10-0.20, and 0.20-0.30 m. The results indicated a homogeneity of the average nutrient contents obtained in the north and south-exposed faces, as well as in the comparison of the same distances in both assessed sun-exposed faces. Effects of trees on soil chemical attributes were verified only when an isolated analysis was carried out in the north-exposed face for K and Al contents. For these attributes, the increased distance in the row was associated with a reduction in their contents in the more superficial and deeper layers, respectively. Trees do not significantly affect soil nutrient availability in the first years of ICLF implantation in systems with homogeneity of solar radiation incidence in the sun-exposed faces although there may be discrete nutrient reductions with the distance of trees.

ABSTRACT Integrated crop-livestock-forest (iCLF) systems have gained prominence in the past decades as an alternative of sustainable land use, particularly in regions in which there is pressure against agricultural expansion in protected ecosystems such as the Brazilian Amazon. In this context, the objective of this study is to evaluate the effects of one year of use of the iCLF system in the Cerrado/Amazon transition region to determine its impact on soil quality compared to other traditional land uses in the region (planted forest, crop, forage, and native forest). The results indicated that the iCLF system did not jeopardize the soil physical quality, and only the crop land use affected the soil physical attributes. The land uses with the lowest impact on the physical condition of the soil were the iCLF system and the planted forest.

ABSTRACT: Research focused on adequate nutrition of plants is essential in modern coffee production to increase yield and develop more efficient management strategies with greater environmental and economic sustainability. The objectives of this study were to establish critical and optimal levels of soil fertility properties for high yielding Arabica coffee crops using the Boundary Line method and, then, relate the macronutrient contents in the diagnostic leaf of coffee to the macronutrients available in the soil using the Quadrant Diagram of the Plant-Soil Relationship (QDpsR). The study made use of a soil chemical analysis database, leaf macronutrient contents, and Arabica coffee yield from five representative coffee-growing regions in Minas Gerais. An analysis of data consistency was performed, and relative fruit yield (RFY) was related to the soil organic matter (SOM), P, K, Ca, and Mg contents in the soil, establishing the boundary line (BL) in each graph. Equations were adjusted from the BL points, and the equation that best fit was selected. Using the QDpsR method, the response plane was divided into four quadrants, where the total leaf contents of N, P, K, Ca, Mg, and S were plotted as a function of the contents of SOM, P, K, Ca, and Mg in the soil, on the y and x axes of the Cartesian coordinate system. The regression equations were adjusted to the pairs of points (y, x) of quadrants III and I and were used to estimate the macronutrient sufficiency ranges from the critical and optimal levels in the soil. The BL method was used to determine the class of good soil fertility for SOM, P, K, Ca, and Mg. The QDpsR method allows determination of response curves for leaf content as a variable of soil contents, making it possible to estimate the sufficiency ranges in the diagnostic leaf of coffee: 33.4-35.8 g kg-1 of N, 1.4-1.6 g kg-1 of P, 24.4-27.0 g kg-1 of K, 11.9-13.6 g kg-1 of Ca, 3.8-4.5 g kg-1 of Mg, and 1.4-1.8 g kg-1 of S; which were consistent with the sufficiency ranges considered suitable for the crop. This study demonstrated the importance of leaf analysis as a tool for evaluation of the nutritional status of Arabica coffee since the technique is consistent with the theoretical principles underlying it.

RESUMO Os resíduos de culturas agrícolas aportados sobre a superfície do solo, além da proteção física, podem liberar quantidades significativas de nutrientes ao solo pela decomposição deles; porém, a disponibilidade desses nutrientes às plantas é um fator pouco estudado. Avaliaram-se os teores totais de C orgânico e N, o pH e a disponibilidade e taxa de recuperação dos macronutrientes provenientes da ciclagem biogeoquímica de diferentes resíduos culturais ao longo do tempo, em solos com texturas construídas. Os tratamentos consistiram em fatorial 6 × 4 × 5, composto por seis tratamentos no primeiro fator, sendo quatro resíduos culturais: milho, braquiária, feijão, estilosantes, e dois controles, ambos sem resíduo e um com adição de fontes inorgânicas dos nutrientes; quatro diferentes texturas formadas a partir de um mesmo solo e cinco tempos de avaliação, após o início da incubação: 0, 25, 75, 125 e 175 dias; utilizou-se delineamento inteiramente casualizado, com quatro repetições. O tipo de resíduo, a textura do solo e o tempo de incubação influenciaram os teores totais de C orgânico e N, o pH, a disponibilidade e a taxa de recuperação de P, K, Ca, Mg e S. Os teores totais de C orgânico e N nos solos diminuíram ao longo da incubação. Os resíduos de braquiária e estilosantes acidificaram o solo. O resíduo de braquiária apresentou-se como potencial fonte de K; e o de feijão, de S. O resíduo de milho apresentou as maiores taxas de recuperação de P em solos de textura média e argilosa.

RESUMO A sustentabilidade dos sistemas conservacionistas de produção agrícola está intimamente ligada ao retorno dos nutrientes ao solo, por meio da decomposição dos resíduos vegetais. O objetivo deste estudo foi avaliar a decomposição de resíduos culturais e a mineralização de nutrientes em solos com diferentes texturas ao longo de 175 dias de incubação. Os tratamentos consistiram em fatorial 6 x 4 x 5, inicialmente composto por seis tratamentos, sendo quatro resíduos culturais: milho, braquiária, feijão, estilosantes e dois controles, ambos sem resíduo e um com adição de fontes inorgânicas dos nutrientes; quatro diferentes texturas formadas a partir de um mesmo solo e cinco tempos de avaliação após o início da incubação: 0, 25, 75, 125 e 175 dias. Utilizou-se delineamento inteiramente casualizado, com quatro repetições. Ao longo do experimento, avaliaram-se a liberação de C-CO2, taxa de decomposição e cinética de mineralização do N, P, K, Ca, Mg, S, Zn e Cu dos resíduos. A textura do solo não influenciou a liberação de C-CO2, a massa seca remanescente e a mineralização dos nutrientes dos resíduos culturais. Os resíduos de estilosantes e de braquiária apresentaram maior liberação de C-CO2 e redução de massa seca que os demais resíduos. A mineralização do N, P e S ocorreu de forma inversa às relações C/N, C/P e C/S. A decomposição dos resíduos culturais foi regulada pelos teores de N e extrativos solúveis em água; e a mineralização de macronutrientes, pelos seus respectivos conteúdos iniciais nos resíduos.

Forest litter decomposition is a major process in returning nutrients to soils and thus promoting wood productivity in the humid tropic. This study aimed to assess decomposition of eucalypt litter in the Rio Doce region, Brazil. Leaf litter was sampled under clonal eucalypt stands aged 2, 4 and 6 years on hillslopes and footslopes. Soil and soil+litter samples were incubated at two levels of soil moisture, temperature and fertilization. C-CO2 emissions from soil measured during 106 days were higher at 32 °C than at 23°C, mainly for the 2-yr-old stand on footslope. When leaf litter was added on soils, C-CO2 emissions were eight times higher, mainly on footslopes, with no effect of stand age. Leaf decomposition in situ, assessed with a litterbag experiment showed a mean weight loss of at least 50% during 365 days, reaching 74% for 2 yr-old stands on footslopes. In comparison with data from the native forest and the literature, no apparent restrictions were found in eucalypt litter decomposition. Differences between in vitro and in situ results, and between eucalypt and native forest, were most likely related to the response of diverse decomposer communities and to substrate quality.

As informações referentes às taxas de recuperação do boro pelo extrator em razão das doses adicionadas são escassas e necessárias para os sistemas de recomendação de adubação e corretivos. Esta pesquisa teve o objetivo de determinar as taxas de recuperação desse nutriente com água fervente e CaCl2 fervente em solos dos Estados da Bahia e Minas Gerais, na ausência e na presença de calagem. O experimento foi instalado em casa de vegetação, utilizando tratamentos em esquema fatorial (6 × 2 + 9) × 6, correspondendo a seis solos com e sem calagem, nove solos sem calagem e seis doses de B. Utilizaram-se blocos casualizados, com três repetições. As unidades experimentais foram constituídas por 0,6 dm3 de solo. A calagem foi calculada com base na análise de solo, seguindo a recomendação de calagem usada para o Estado de Minas Gerais. Após 15 dias de incubação, os solos receberam doses de B (0,0; 1,5; 3,0; 6,0; 9,0; e 15 mg dm-3), fazendo-se uma nova incubação por um período de 45 dias. Usou-se ácido bórico como fonte de B. Terminada a incubação, o teor de B disponível foi extraído com água fervente e CaCl2 5 mmol L-1 fervente, sendo a dosagem feita com azometina-H. Foram feitas análises de regressão e correlação para as diversas variáveis. O B extraído do solo com água fervente e o CaCl2 fervente, independentemente da calagem, aumentou linearmente com a elevação das doses aplicadas desse nutriente aos solos. Os extratores água fervente e o CaCl2fervente não são sensíveis à calagem. As taxas de recuperação de B dos solos pelos extratores usados variam de acordo com os teores de matéria orgânica, a quantidade e qualidade de argila e pelo equivalente de umidade. Os extratores utilizados foram altamente correlacionados entre si na extração do B do solo.

O número de passadas das máquinas, os tipos de rodados e a alta umidade do solo durante as operações de colheita agravam o processo de compactação, devendo-se conhecer esses impactos e quais alternativas para reduzí-los. O objetivo deste estudo foi avaliar o impacto de diferentes frequências de tráfego doforwarder e o efeito de condições distintas de resíduos da colheita do eucalipto ao fim da rotação subsequente na produtividade, nos atributos físicos do solo e nos teores de matéria orgânica de um Latossolo Vermelho (LV), localizado em São João Evangelista, MG, e um Latossolo Amarelo (LA), localizado em Belo Oriente, MG. Os tratamentos consistiram de um esquema fatorial 2 × 3, sendo: duas ou oito passadas na entrelinha sobre resíduo da colheita sem casca; com casca; e sem resíduo. A perda de produtividade dos plantios pela compactação do solo proveniente das passadas doforwarder é atenuada com a permanência dos resíduos da colheita especialmente com a manutenção da casca na área. A remoção de resíduo, particularmente quando há remoção da casca, leva à redução dos teores de C orgânico total e de frações mais lábeis de C e N do solo. O tráfego doforwarder na colheita do eucalipto da rotação anterior sobre solo sem resíduos promove perdas na qualidade física do solo, com aumento da densidade do solo e resistência à penetração, e redução na porosidade e condutividade hidráulica do solo. Esses efeitos negativos perduraram até o final da rotação seguinte.

Melon is one of the most demanding cucurbits regarding fertilization, requiring knowledge of soils, crop nutritional requirements, time of application, and nutrient use efficiency for proper fertilization. Developing support systems for decision-making for fertilization that considers these variables in nutrient requirement and supply is necessary. The objective of this study was parameterization of a fertilizer recommendation system for melon (Ferticalc-melon) based on nutritional balance. To estimate fertilizer recommendation, the system considers the requirement subsystem (REQ), which includes the demand for nutrients by the plant, and the supply subsystem (SUP), which corresponds to the supply of nutrients through the soil and irrigation water. After determining the REQtotal and SUPtotal, the system calculates the nutrient balances for N, P, K, Ca, Mg, and S, recommending fertilizer application if the balance is negative (SUP < REQ), but not if the balance is positive or zero (SUP ≥ REQ). Simulations were made for different melon types (Yellow, Cantaloupe, Galia and Piel-de-sapo), with expected yield of 45 t ha-1. The system estimated that Galia type was the least demanding in P, while Piel-de-sapo was the most demanding. Cantaloupe was the least demanding for N and Ca, while the Yellow type required less K, Mg, and S. As compared to other fertilizer recommendation methods adopted in Brazil, the Ferticalc system was more dynamic and flexible. Although the system has shown satisfactory results, it needs to be evaluated under field conditions to improve its recommendations.

O experimento foi conduzido em casa de vegetação da Universidade Federal de Minas Gerais, com o objetivo de avaliar o crescimento inicial, a eficiência de uso do P e frações de fósforo em três espécies florestais submetidas a quatro níveis de P. O delineamento experimental utilizado foi o inteiramente casualizado em arranjo fatorial (3 x 4) com três repetições. Mudas de gonçalo-alves (Astronium fraxinifolium Schott) e barbatimão (Stryphnodendron adstringens (Mart.) Coville), espécies nativas do Cerrado, e acácia-australiana (Acacia mangium Willd.), espécie exótica, foram cultivadas em Latossolo Vermelho-Amarelo adubado com 0, 150, 300 e 600 mg dm-3 de P.Aos 240 dias após a emergência, as plantas foram avaliadas quanto a altura, diâmetro do colo, produção de matéria seca, fósforo total solúvel em ácido e frações de P. As diferentes doses de fósforo influenciaram o crescimento inicial, a absorção e os teores totais e das frações de P, nas três espécies. A espécie acácia-australiana apresentou maior crescimento em relação às espécies nativas nas maiores doses de P. As espécies do Cerrado, por sua vez, apresentaram maior investimento em raízes e maior armazenamento de fósforo em formas inorgânicas, com destaque para o barbatimão. A relação P inorgânico:P orgânico mostrou-se adequada para a avaliação do status nutricional de P de espécies florestais.

ABSTRACT Biogeochemical cycling is essential to establish and maintain plant and animal communities. Litter is one of main compartments of this cycle, and the kinetics of leaf decomposition in forest litter depend on the chemical composition and environmental conditions. This study evaluated the effect of leaf composition and environmental conditions on leaf decomposition of native Atlantic Forest trees. The following species were analyzed: Mabea fistulifera Mart., Bauhinia forficata Link., Aegiphila sellowiana Cham., Zeyheria tuberculosa (Vell), Luehea grandiflora Mart. et. Zucc., Croton floribundus Spreng., Trema micrantha (L) Blume, Cassia ferruginea (Schrad) Schrad ex DC, Senna macranthera (DC ex Collad.) H. S. Irwin and Barney and Schinus terebinthifolius Raddi (Anacardiaceae). For each species, litter bags were distributed on and fixed to the soil surface of soil-filled pots (in a greenhouse), or directly to the surface of the same soil type in a natural forest (field). Every 30 days, the dry weight and soil basal respiration in both environments were determined. The cumulative decomposition of leaves varied according to the species, leaf nutrient content and environment. In general, the decomposition rate was lowest for Aegiphila sellowiana and fastest for Bauhinia forficate and Schinus terebinthifolius. This trend was similar under the controlled conditions of a greenhouse and in the field. The selection of species with a differentiated decomposition pattern, suited for different stages of the recovery process, can help improve soil restoration.

ABSTRACT For the development of nutrient budget models to recommend lime and fertilizers for agricultural and forestry crops, curves of plant growth and nutrient accumulation are required. Information about how nutrients are partitioned between the different plant organs is also necessary, but still scarce for pine in Brazil. This study evaluated the growth, biomass partitioning, and nutrient dynamics in pine forests in southern Brazil. To this end, we assessed unthinned 2, 4, 6, and 8-year-old stands of Pinus taeda L. Three plots of 20 × 30 m per stand were delimited, in which three trees of different classes of diameter at breast height (DBH) were chosen. These trees were measured, felled, and the weight of their fresh components (leaves, branches, bark, and wood) was evaluated. Samples of each tree compartment and from the forest litter were taken to determine dry weight and nutrient content. From trees of the mean DBH class, the roots were also collected and the dry weight and nutrient contents determined. The same sampling procedure was carried out with soil for physical and chemical characterization. Regression models were adjusted to estimate growth, nutrient uptake, and nutrient use efficiency of pine trees, based on data collected in this and previous studies. The equations developed in this research can be used in nutrient budget models as well as in other simulation models, to establish recommendations of lime and fertilizers for Pinus taeda stands in southern Brazil.

A toxicidade por Al em plantas se dá de várias maneiras, sendo a inibição do crescimento radicular uma das primeiras a se expressar, embora não seja prontamente perceptível em razão do hábito de crescimento das raízes. O objetivo desse trabalho foi avaliar a tolerância da erva-mate ao Al por meio do crescimento de raízes de mudas submetidas a doses crescentes do elemento. Para isso, testaram-se, três clones (C1, C2 e C3), doses de 100, 500, 1.000 e 2.000 μmol L-1 de Al (AlCAlCl36H2O) e um controle sem Al. Após 50 dias, determinaram-se massa seca das raízes, comprimento e volume total do sistema radicular, comprimento e volume total das raízes em diferentes diâmetros. O Al influenciou positivamente o crescimento das raízes de todos os clones. O maior comprimento radicular foi apresentado pelo clone C2, seguido pelo C3 e C1 em doses superiores a 1.500 μmol L-1. Os maiores volumes foram obtidos para os clones C3, C2 e C1 nas doses respectivas de 2.000, 1.355 e 1.988 μmol L-1 de Al. Maiores comprimentos e volume radicular foram provenientes de raízes finas em doses superiores a 1.500 μmol L-1 de Al. O Al estimula o crescimento radicular e os clones testados apresentam tolerância diferencial ao Al.

Yerba mate (Ilex paraguariensis) is a tree species native to the subtropical regions of South America, and is found in Brazil predominantly in the southern region. Despite the historical importance in this region, so far, studies on crop nutrition to improve yields are scarce. Thus, this study evaluated the effect of potassium rates on K soil availability, and the yield and nutritional status of yerba mate. The experiment was conducted in São Mateus do Sul, State of Paraná, on a Humox soil, where K2O rates of 0, 20, 40, 80, 160, and 320 kg ha-1 were tested on 7-year-old plantations. The experiment was harvested 24 months after installation by removing approximately 95 % of the canopy that had sprouted from the previous harvest. The soil was evaluated for K availability in the layers 0-10, 0-20, 10-20, and 20-40 cm. The plant parts leaf fresh matter (LM), twigs (TW), thick branches (BR) and commercial yerba mate (COYM), i.e., LM+TW, were analyzed. In addition, the relationship between fresh matter/dry matter (FM/DM) and K concentration in LM, AG and BR were evaluated. The fertilization increased K availability in all evaluated soil layers, indicating good mobility of the nutrient even at low rates. Yerba mate responded positively to increasing K2O rates with higher yields of all harvested components. The crop proved K-demanding, with a maximum COYM yield of 28.5 t ha-1, when 72 mg dm-3 K was available in the 0-20 cm layer. Yerba mate in the plant production stage requires soil K availability at medium to high level; in clayey soil with low K availability, a rate of 300 kg ha-1 K2O should be applied at 24 month intervals to obtain high yields. A leaf K concentration of 16.0 g ha-1 is suitable for yerba mate in the growth stage.

O conhecimento das características do sistema radicular auxilia na definição de práticas de preparo de solo e fertilização. O objetivo deste trabalho foi estimar a biomassa, o conteúdo de nutrientes em raízes, o comprimento e a área de raízes finas e médias e a eficiência de utilização de macronutrientes da teca (Tectona grandis) para formação de área radicular em diferentes profundidades do solo. A separação das raízes do solo foi feita estratificando-as em grossas (>5 mm), médias (2 a 5 mm) e finas (< 2 mm), para determinação de N, P, K, Ca, Mg e S. As raízes médias e finas (± 0,5 g) foram digitalizadas e quantificadas por intermédio do programa QuantRoot®, obtendo-se o diâmetro, a área e o comprimento. A biomassa total de raízes finas e médias foi de 1.335 e 1.258 kg ha-1 respectivamente, e 56,2% das raízes finas e 44,4% das raízes médias concentram-se nos primeiros 20 cm do solo. O comprimento total de raízes finas foi de 8.237 km ha-1, com 57,4% nos primeiros 20 cm de profundidade. A superfície total de raízes finas foi de 18.441 m² ha-1, com 57% dessa superfície nos primeiros 20 cm do solo. A quantidade total de nutrientes nas raízes, na camada de solo estudada (0-60 cm), em ordem decrescente, foi K > Ca > N > Mg > P > S. O fósforo e o enxofre são os nutrientes com maior eficiência de utilização para formação de área radicular em plantios de teca.

Inconclusive responses of the adult coffee plant to phosphorus fertilization have been reported in the literature, especially when dealing with application of this nutrient in high density planting systems. Thus, this study was carried out for the purpose of assessing the response of adult coffee plants at high planting density in full production (in regard to yield and their biennial cycle/stability) to the addition of different sources and application rates of P in the Zona da Mata region of Minas Gerais, Brazil. The experiment with coffee plants of the Catucaí Amarelo 6/30 variety was carried out over four growing seasons. Treatments were arranged in a full factorial design [(4 × 3) + 1] consisting of four P sources (monoammonium phosphate, simple superphosphate, natural reactive rock phosphate from Algeria (Djebel-Onk), and FH 550®), three P rates (100, 200, and 400 kg ha-1 year-1 of P2O5), and an additional treatment without application of the nutrient (0 kg ha-¹ year-¹). A randomized block experimental design was used with three replicates. The four seasons were evaluated as subplots in a split plot experiment. The P contents in soil and leaves increased with increased rates of P application. However, there was no effect from P application on the yield and its biennial cycle/stability regardless of the source used over the four seasons assessed.

Eucalyptus Shoot Blight in the Vale do Rio Doce (ESBVRD) is an anomaly that leads to reduced growth and, in more extreme cases, to death of eucalyptus plants. Initially diagnosed in plantations in the region of the Vale do Rio Doce, in the State of Minas Gerais, Brazil, this problem has also been found in plantations in other regions of the country and even in other countries. Although the symptoms of this anomaly are well-known, its causes are not yet understood. The aim of this study was to evaluate the cause-effect relationship between accumulation of manganese (Mn) in eucalyptus clones and ESBVRD. Characterization of the environment in areas of greater occurrence of this problem in regard to soil, climate and fluctuation of the water table was undertaken in eucalyptus plantations of the Celulose Nipo-brasileira S.A. (Cenibra) company in the region of the Vale do Rio Doce. Plant tissues were sampled in two situations. In the first situation, diagnosis occurred in the initial phase of the anomaly in clones with differentiated tolerance to the problem; in the second situation, diagnosis was made in a single clone, considered to be sensitive, in two time periods - in the phase with the strong presence of symptoms and in the recovery phase, in areas of occurrence and in areas of escape from the problem. The most ESBVRD-sensitive clone showed much higher (4.8 times higher) leaf Mn contents than more tolerant clones. In plants with the anomaly, Mn leaf contents were greater than 3,070 mg kg-1, much greater than the quantity found in those without the anomaly (734 mg kg-1). In the period in which the symptoms began to wane, there was a sharp decline in leaf Mn contents, from 2,194 to 847 mg kg-1. Manganese content in the above ground part and plant litter (44.4 g ha-1) in the area of occurrence of the anomaly was three times greater than that found in these same components (14.1 g ha-1) in the area of absence of the symptom. Based on the evidence found, such as the existence of environmental conditions favorable to high Mn availability to the plants in the areas of greatest incidence of ESBVRD, greater uptake of Mn in sensitive clones and in plants with symptoms, and a synchronism between the intensity of symptoms of ESBVRD and leaf Mn contents, it may be inferred that temporary excess of Mn in eucalyptus plants is closely related to ESBVRD.

O critério atualmente adotado para a indicação de adubação da soja, embasado no estabelecimento de níveis críticos, tem permitido a obtenção de produtividades médias em torno de 3.600 kg ha-1. Contudo, para a obtenção de produtividades mais elevadas e econômicas, sem prejuízos ao equilíbrio ambiental, deve-se visar à definição de modelos quantitativos que permitam estimar a demanda por nutrientes, em função do potencial de produção almejado. Modelos desta natureza vêm sendo estabelecidos no Departamento de Solos da Universidade Federal de Viçosa, para o desenvolvimento de sistemas de recomendação de corretivos e fertilizantes, denominados genericamente de FERTCALC® e NUTRICALC®. A partir de um banco de dados, formado pelo monitoramento nutricional de lavouras comerciais em Mato Grosso do Sul, foram estabelecidos modelos matemáticos para a estimativa da demanda nutricional, em função da produtividade e do acúmulo de nutrientes no terceiro trifólio com pecíolo, ou, então, do coeficiente de utilização biológica (CUB). Demonstrou-se que, para uma dada produtividade, o produto da matéria seca da folha índice com os teores de nutrientes, considerados como suficientes para a cultura, resulta no conteúdo nutricional desta, que, por sua vez, apresenta relação com o conteúdo nutricional no caule, folhas, vagens e nos grãos. A quantidade de nutrientes imobilizada na planta de soja também pode ser calculada a partir do quociente entre a produção de grãos e de matéria seca de parte aérea e os valores de CUB estabelecidos. Os métodos propostos permitem estimativa de valores próximos da demanda nutricional pela soja.

A diagnose dos estados nutricionais do algodoeiro e da soja, pelo método de níveis críticos, tem-se embasado em faixas de suficiência estabelecidas há muitos anos, com pequenas adequações no período. Contudo, considerando-se que os teores foliares podem variar, dentre outros fatores, em função do tipo de amostra coletada e do potencial produtivo da cultura, torna-se importante a definição de valores de referência regionais. Este trabalho teve como objetivo estabelecer os teores adequados de nutrientes para algodoeiro e soja, por meio do ajuste de modelos de regressão para o teor foliar em função do índice de equilíbrio nutricional definido pelo Sistema Integrado de Diagnose e Recomendação (DRIS). Utilizou-se um banco de dados, constituído das produtividades e dos teores de nutrientes em amostras foliares de ambas as espécies, coletadas em talhões de lavouras comerciais e em parcelas experimentais, em Mato Grosso do Sul e Mato Grosso. Foram obtidas faixas de suficiência para as folhas índice de algodoeiro (quinta folha totalmente formada, a partir do ápice) e de soja (terceiro trifólio sem e com pecíolo), com amplitude menor do que aquela estabelecida na literatura para estas culturas. Especificamente, para a soja, confirmou-se a existência de diferenças nos valores de referência em função do tipo de folha índice amostrado. Amostras de folha índice sem pecíolo produzem teores significativamente maiores de N, P, B, Fe, Mn e Zn e menores de K, em relação aos das amostras com pecíolo. A desconsideração do modo de amostragem pode induzir a falsos diagnósticos de deficiências ou excessos nutricionais.

Although the 3-PG model is widely used for forest productivity calculations, there are processes that do not present appropriate physical treatment. The aim of this study was to generate a tool to improve the water balance calculation in the model to enhance the energy balance and transpiration process. The calculation of transpiration was modified to account for variations in solar radiation with the inclination and azimuth of the terrain; the vapor pressure deficit was changed based on the relative humidity and air temperature; and the stomatal conductance varied according to solar radiation, vapor pressure deficit and air temperature. The water storage in the soil varied with the depth of the root system and the total water availability (TWA) in the soil. The assessment was also changed from a monthly to an hourly basis. The study was conducted in areas surrounding Cenibra, and the data were collected from the Rio Doce river basin, in the Brazilian state of Minas Gerais. Taken together, these modifications improved growth - modeling processes and enhanced the capacity of this analytical tool to differentiate intra - region productivity.