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Abstract The compositional nutrient diagnosis—CND method is a standard tool for evaluating plant nutritional status. Adjustments are crucial to elevate accuracy. The effectiveness of such methodological refinements should be rigorously assessed through accuracy tests that are benchmarked against the prescient diagnostic analysis—PDA methodology. The objective of this investigation was to refine the CND technique for a more precise evaluation of N, P, and B nutrient status in cotton. The study’s database encompasses 144 data points pertaining to crop yield and foliar nutrient concentrations from cotton plantations in the Cerrado biome of Brazil. Subsequently, the CND norms were established through rigorous calibration. Three separate nutrient-dose trials, each featuring four levels of N, P and B, were carried out to assess plant true nutritional status. Adjustments were made to the nutrient responsiveness range—NRr (0.5 and 1.0), while yield response—YR were scrutinized at threshold levels (5% and 10%). The prerequisites for achieving high diagnostic accuracy were nutrient specific. For N, maximal accuracy was linked only to the YR parameter (YR = 10%). For P, the most precise outcomes were attained with a NRr = 0.5 and YI = 5%. For B, highest diagnostic accuracy when the NRr = 1.0 and YI = 10%. These insights highlight the need to fine-tune the CND method for reliable nutritional evaluations and cotton crop productivity optimization.

ABSTRACT Increasing soybean yield in the MATOPIBA region can be attributed to fertility management, which is crucial to achieving maximum agronomic efficiency. Therefore, the proper management begins with the assessment of plant nutrition. This study aimed to evaluate soybean nutritional status in western Bahia using the Diagnosis and Recommendation Integrated System (DRIS). Database comprised 153 samples from commercial fields located in the research area. To carry out the evaluation using the DRIS method, the database contained information on nutritional levels and leaf productivity of the sampled areas. Database was divided into high-productivity populations (reference population) and low-productivity populations, based on the inflection point value of the cumulative cubic function of yield. The DRIS method allowed for evaluating the potential response to fertilization; however, this method was inefficient in recommending fertilizer doses in both subpopulations. For the sufficiency levels proposed by DRIS, the nutrients N, K, Ca, Mg and S had their maximum and minimum limits reduced, while Cu, Fe and Zn had their ranges of sufficiency expanded, when compared with ranges proposed by other authors. In addition, Zn and Mn were more limiting due to lack for the high-yield subpopulation, and P and Mn for the low-yield subpopulation. The most limiting nutrients due to excess were P and Zn for the high-yield, while K and S were limiting for the low yield subpopulation.

Adequate management of agricultural crops requires, among other things, accessible and sufficiently accurate methods for assessing plant nutrition and crop vegetation status and for agricultural production estimation. Sustainable technologies are based on correct decisions, prompt interventions and appropriate works, and correct information in real time, and the obtaining information methods can be simple, accessible, and appropriate in relation to different user categories (e.g., farmers, researchers, decision makers). This study used mineral fertilization (NPK), with 11 experimental variants, to ensure a controlled differentiated nutrition of the wheat plants, “Alex” cultivar. Regression analysis was used to obtain models in estimating wheat production, by methods based on: (a) NPK fertilizers applied (F) in the 11 experimental variants; (b) physiological indices (PI), represented by the chlorophyll content (Chl), and plant nutrition status on the experimental variants, in terms of macroelement content in the leaves, evaluated by foliar diagnosis (Nfd, Pfd, Kfd); (c) imaging analysis (IA) based on digital images of the wheat experimental variants, and calculated indices. A set of models was obtained, with different precision levels and statistical safety: R2 = 0.763, p = 0.013 for the model based on applied fertilizers (NPKF); R2 = 0.883, p < 0.01 for the model based on foliar diagnosis (NPKfd); R2 = 0.857, p < 0.01 for the model based on chlorophyll content (Chl); R2 = 0.975, p < 0.01 for the model based on normalized rgb color parameters (RGB color system); R2 = 0.925, p < 0.01 for the model based on the DGCI calculated index. The model based on applied fertilizers (F model) was tested in relation to wheat production data, for a period of six years, communicated by other studies. Fit degree analysis between predicted yield based on the F model and real yield (six-year average) was confirmed by R2 = 0.717, compared to R2 = 0.763 for the F model in this study. The models obtained in this study, related to the “Alex” wheat cultivar, can be used for other studies, but with a certain margin of error, given the coefficient values, specific to the obtained equations. The approach concept, methods, and models presented can be opportunities for other studies to facilitate their comparative analysis, their adaptation, and/or development in the form of new models that are useful in different studies, research, or agricultural practices, for their integration into crop management strategies.

The peach palm, a native fruit of Central America and the Amazon rainforest, is cultivated for fruit production and extraction of palm hearts. The aim of this study was to establish reference values using DRIS, in groves of the peach palm grown in as a monocrop and under agroforestry systems (AFS). Eighty-one palm groves were monitored for two consecutive years, giving a total of 162 composite leaf samples. Samples were taken from November to December of 2012 and 2013. The palm groves were classified into three groups for production of the DRIS: i) peach palm grown as a monocrop; ii) peach palm grown under AFS and iii) peach palm grown under both systems of production. DRIS indices were calculated with the Jones formula using logarithmic transformation. The groves were then classified by the method of fertilisation response potential, as regards a nutrient status of insufficient, balanced and excessive, for each of the resulting DRIS norms. For most cases, the nutrient status obtained with specific norms were the same as those obtained with the generic norm. The use of generic norms results in diagnoses, which are similar to those obtained with specific norms, and can be recommended for evaluating the nutrient status of peach palms produced under different management systems. = A pupunheira, uma frutífera nativa da América Central e da Floresta Amazônica, vem sendo cultivada para produção de frutos e extração de palmito. Objetivou-se com o presente trabalho estabelecer os valores de referência, pelo DRIS, para palmitais de pupunheira cultivada em monocultivo e em sistemas agroflorestais (SAFs). Foram monitorados 81 palmitais em dois anos consecutivos, totalizando 162 amostras foliares compostas. As amostragens foram realizadas de novembro a dezembro dos anos de 2012 e 2013. Os palmitais foram classificados em três grupos para a produção das normas DRIS: i) pupunheiras cultivadas em monocultivo; ii) pupunheiras cultivadas em SAFs e iii) pupunheiras cultivadas em ambos sistemas de produção. Os índices DRIS foram calculados pela fórmula de Jones com transformação logarítmica. Os palmitais foram a seguir classificados pelo método do potencial de resposta à adubação, quanto ao estado nutricional, em insuficiente, balanceado e em excesso, para cada uma das normas DRIS obtidas. Para a maioria dos casos, o estado nutricional obtido pelas normas específicas foram os mesmos que aqueles obtidos pela norma genérica. O uso de normas genéricas resulta em diagnósticos semelhantes aos obtidos com normas específicas, podendo ser recomendado para avaliar o estado nutricional de pupunheiras, produzidas em diferentes condições de manejo.

Several studies have pointed out the promising use of nutritional diagnosis methods for the determination of optimum nutrient contents in plant tissues. The present investigation was carried out in different oases in Southern Tunisia to determine reference values for the interpretation of leaf analyses of date palm (Phoenix dactylifera) Deglet Nour cultivar with the Critical Value Approach (CVA) and the Compositional Nutrient Diagnosis (CND). A database (n = 100) of yield and mineral concentrations taken from date palm leaflets in October, at the maturity stage of dates, was used. The yield cut-off between low-yield and high-yield subpopulations, selected from cumulative variance ratio functions across survey data, was 76 kg palm−1 and the global nutrient imbalance index (CNDr2) was 10.06. Critical CND nutrient indices were found to be symmetrical around zero as follows: (1.59; +1.59) for IN, (−0.44, +0.44) for IP, (−0.63, +0.63) for IK, (−0.94, +0.94) for ICa, (−1.05, +1.05) for IMg, (−0.80, +0.80) for IFe, (−0.74, +0.74) for ICu, (−0.80, +0.80) for IB, (−0.93, +0.93) for IZn, (−1.04, +1.04) for IMn, and (−1.03, +1.03) for the residual value. Compared to CND, the CVA approach shows weak detection of the nutrients that cause nutritional imbalance. CND indices revealed, except for N, the presence of nutrient imbalances and the necessity to correct the mineral nutrition of date palm in the Kebeli oases.

The present study aims at developing an organic fertilization program of an olive orchard located in the North-west of Tunisia. Soil analyses showed an acceptable level of P2O5 and K2O in the soil of the studied farm. Based on leaves and olive fruit analyses, the requirements in N, P and K nutrients of the olive tree for a yield of 20 tons per ha were evaluated at 171 kg N/ha, 40 kg P2O5/ha and 170 kg K2O/ha. As for the required nutrient additions to soil, they were evaluated at 133 kg N/ha, 76 kg P2O5/ha and 264 kg K2O/ha. In order to satisfy the needs of the olive tree, organic compost was used as soil amendement. The required compost amendments have been evaluated to 4 tons/ha at the age of 3/6 years, to 10 tons/ha at the age of 6/10 years and to 20 tons/ha at an age greater than 10 years.

Development of prediction models for the quality of apples is useful in guiding fruit tree nutrition and in optimising fruit management. The interrelationships between the leaf nutrient contents and some fruit quality indices were studied in five apple cultivars - Generos, Florina, Delicios de Voinesti, Jonathan and Pionier. Highly significant relationships between N and Fe contents (R2 = 0.734; P < 0.01) and between Cu and K (R2 = 0.702; P < 0.01) were found. Acidity was negatively correlated with soluble solids content in the cvs Generos, Delicios de Voinesti and Jonathan, whereas the respective correlation in the apple cv. Pionier was positive. In cv. Florina fruits no significant correlation was found between acidity and soluble solids content. Among macroelements, nitrogen had a considerable contribution to fruit acidity and this allows to predict this index with a high degree of safety (R2 = 0.690; RMSEPN = 0.105). Microelements have a lower contribution to acidity and a higher one to the sugar accumulation; in case of Zn are R2 = 0.809; RMSEPZn = 4.250.

Para o arroz irrigado, poucos trabalhos utilizam métodos de diagnose foliar desenvolvidos para as condições locais de clima, solo ou cultivares. O objetivo deste trabalho foi avaliar os métodos da Diagnose da Composição Nutricional e da Chance Matemática na definição dos padrões nutricionais de lavouras arrozeiras do Estado do Rio Grande do Sul. Resultados de produtividade de grãos e teores foliares de N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, Zn e Mo de 356 lavouras arrozeiras cultivadas sob sistema de irrigação por inundação foram utilizados para a determinação das faixas de suficiência calculadas pelo método da Chance Matemática. As faixas de suficiência foram comparadas com valores críticos propostos pela literatura e com o intervalo de confiança do teor médio dos nutrientes em lavouras consideradas nutricionalmente equilibradas, identificadas pelo método Diagnose da Composição Nutricional. Observou-se pouca concordância entre os valores das faixas de suficiência indicados pelos métodos da Chance Matemática e da Diagnose da Composição Nutricional e os respectivos valores indicados na literatura. A faixa de teores foliares adequados, consistentes com maior produtividade média das lavouras arrozeiras, foi indicada ser de 23 a 28 g kg-1 para N; 11 a 14 g kg-1 para K; 1,4 a 2,0 g kg-1 para S; 6 a 12 mg kg-1 para B; e 70 a 200 mg kg-1 para Fe. Para os teores foliares de P, Ca, Mg, B, Cu, Mn e Zn e Mo nenhuma das faixas adequadas testadas indicou capacidade para distinguir as lavouras arrozeiras quanto à produtividade média.For rice, few studies use foliar analysis methods developed for local conditions of climate, soil or cultivars. The purpose of this study was to evaluate the methods of Compositional Nutrient Diagnosis and of Mathematical Chance to define nutritional standards for rice fields in Rio Grande do Sul state, Brazil. Data of 356 irrigated rice fields for grain yield and foliar contents (N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, Zn, and Mo) were used to calculate the sufficiency ranges by the Mathematical Chance method. The sufficiency ranges were compared with critical values proposed in the literature and with the confidence interval of the average nutrient contents of nutritionally balanced crops identified by the Compositional Nutrient Diagnosis method. There was little agreement between the sufficiency ranges indicated by the methods of Mathematical Chance and Compositional Nutrient Diagnosis and the respective values in the literature. The appropriate range of foliar contents, consistent with highest average yield of rice fields, was 23-28 g kg-1 for N; 11-14 g kg-1 for K; 1.4-2.0 g kg-1 for S; 6-12 mg kg-1 for B; and 70-200 mg kg-1 for Fe. For the contents of P, Ca, Mg, B, Cu, Mn, Zn, and Mo none of the tested ranges allowed to discriminate rice yield.

A survey was conducted for assessment of soil fertility status, leaf nutrient concentration and identification of yield limiting nutrients in twenty six oil palm (Elaeis guineensis Jacq.) plantations in Surat district of Gujarat. Soil pH, electrical conductivity (EC), organic carbon (OC), available potassium (K) (NH4OAc-K), available phosphorus (P) (Olsen-P), exchangeable calcium (Ca) (Exch. Ca) and magnesium (Mg) (Exch. Mg), available sulphur (S) (CaCl2-S) and hot water soluble boron (B) (HWB) content in surface (0-20 cm depth) and subsurface (20-40 cm depth) soil layers varied widely. Diagnosis and Recommendation Integrated System (DRIS) norms were established for different nutrient expressions and it was used to compute DRIS indices. As per DRIS indices, the order of requirement of nutrients in the area was found to be K > nitrogen (N) > B > P > Mg. Optimum leaf nutrient ranges as per DRIS norms varied from 2.63 to 2.85%, 0.16 to 0.18%, 0.56 to 0.88%, 0.34 to 0.84% and 9.10 to 32.5 mg/kg for N, P, K, Mg and B respectively. On the basis of DRIS derived optimum ranges, 65, 31, 35 and 8 per cent leaf samples had less than optimum concentration of N, P, K and B respectively. The optimum ranges developed could be used for efficient nutrient management.

Both N excess and deficiency may affect cotton yield and quality. It would therefore be useful to base the N management fertilization on the monitoring of the nutritional status. This study investigated the correlations among the following determination methods of the N nutritional status of cotton (Gossypium hirsutum L., var. Latifolia): chlorophyll readings (SPAD-502®, Minolta), specific-ion nitrate meter (Nitrate Meter C-141, Horiba-Cardy®), and laboratory analysis (conventional foliar diagnosis). Samples were taken weekly from two weeks before flowering to the fifth week after the first flower. The experiment was conducted on the Fazenda Santa Tereza, Itapeva, State of São Paulo, Brazil. The crop was fertilized with 40 kg ha-1 N at planting and 0, 30, 60, 90, and 120 kg ha-1 of side-dressed N. The range of leaf N contents reported as adequate for samples taken 80-90 days after plant emergence (traditional foliar diagnosis) may be used as reference from the beginning of flowering when the plant is not stressed. Specific-ion nitrate meter readings can be used as a nutritional indicator of cotton nutrition from one week after pinhead until the third week of flowering. In this case, plants are well-nourished when readings exceed 8,000 mg L-1 NO3-. The chlorophyll meter can also be used to estimate the nutritional status of cotton from the third week of flowering. In this case the readings should be above 48 in well-nourished plants.Tanto o excesso como a deficiência de N podem levar a decréscimos na produção e qualidade do algodão. Assim, o monitoramento do estado nutricional da planta pode ajudar no manejo da adubação nitrogenada. Um experimento foi realizado para estudar as correlações entre métodos de determinação do estado nutricional do algodoeiro (Gossypium hirsutum L., var. Latifolia). Os métodos usados foram um medidor de clorofila (SPAD-502®, Minolta), um medidor específico de ions para nitrato (Nitrate Meter C-141, Horiba-Cardy®) e análise de nitrogênio do tecido, em laboratório (Diagnose foliar convencional). Foram coletadas amostras desde duas semanas antes do florescimento até a quinta semana depois da primeira flor. O experimento foi conduzido na Fazenda Santa Tereza, Itapeva, São Paulo, Brasil. A cultura recebeu 40 kg ha-1 de N na semeadura e mais 0, 30, 60, 90 e 120 kg ha-1 de N em cobertura. A faixa de teores de N tida como adequada na diagnose foliar tradicional (com amostragem feita aos 80-90 dias após a emergência da cultura) pode ser usada como referência desde o começo do florescimento, desde que a planta não se encontre sob stress. As leituras de nitrato com o medidor específico de íons podem ser utilizadas como um indicador do estado nutricional do algodoeiro desde uma semana depois do aparecimento do botão floral até a terceira semana de florescimento. Assim, as plantas estarão bem nutridas quando as leituras forem maiores que 8.000 mg L-1 de NO3-. O medidor de clorofila pode também ser usado na estimativa do estado nutricional do algodoeiro a partir da terceira semana de florescimento. Nesse caso, as leituras iguais ou acima de 50 indicam plantas bem nutridas.

A análise dos teores de nutrientes de folhas de soja é um dos métodos mais eficientes para avaliar o estado nutricional da lavoura. O objetivo deste estudo foi caracterizar a variabilidade espacial dos teores foliares de nutrientes e da produtividade da cultura da soja num Latossolo Vermelho sob sistema semeadura direta durante dois anos. A área do experimento media 120 x 160 m, totalizando 1,92 ha. As amostras de folhas e os dados de produtividade da soja foram coletados em grade regular de 20 m, totalizando 63 pontos de amostragem nos anos de 1986 e 1988. O teor de nutrientes (N, P, K, Ca, Mg, S, B, Cu, Fe, Mn e Zn) foi determinado analisando-se a terceira folha com pecíolo a partir do ápice de cinco plantas, em locais circunvizinhos de cada um dos pontos de amostragem. As produtividades de soja foram quantificadas em subparcelas de 5 m², sendo posteriormente transformadas para kg ha-1. Os dados foram analisados pela estatística descritiva, a fim de verificar os parâmetros de tendência central e dispersão. A variabilidade espacial foi determinada pelo cálculo do semivariograma e construção de mapas de contorno por meio dos valores obtidos na interpolação por krigagem ordinária. Houve dependência espacial para os teores foliares de alguns nutrientes e para a produtividade de grãos de soja passível de ser mapeada em uma área com cerca de 2 ha, adubada de maneira homogênea. A dependência espacial não ocorreu de forma constante ao longo do tempo, o que deve ser considerado em estudos com cultivos sequenciais. A dependência espacial da produtividade de soja aumentou entre os anos estudados. Entre os nutrientes aplicados anualmente, via adubação, verificou-se a formação de um padrão de distribuição espacial, em 1986 e em 1988, especialmente para os teores de P.The chemical analysis of plant tissue is an efficient method to assess the nutritional status. This study aimed to characterize the spatial variability of plant nutrients and soybean yield in an experimental area (120 x 160 m, totaling 1.92 ha) of a Rhodic Hapludox under no tillage for two years. Soybean leaf and grain yield were sampled at 63 points in a regular 20 m grid. Plant nutrient contents (N, P, K, Ca, Mg, Cu, Fe, Mn, and Zn) were determined analyzing the 3rd leaf from the top, collected from five plants randomly chosen near the sampling points. The crop yield was measured in 5 m² subplots and expressed in kg ha-1. Data were analyzed using descriptive statistics to assess the measures of central tendency and dispersion. Spatial variability was analyzed using semivariogram parameters and contour maps based on interpolation by ordinary kriging. Spatial dependence was observed for some foliar nutrient contents and crop productivity in a homogeneously fertilized area of about 2 ha. Spatial dependence was not constant over time, which should be taken into account in studies with sequential crops. The spatial dependence of soybean yield increased in the two years studied. Among the nutrients applied annually by fertilization, the formation of a spatial pattern was observed in 1986 and 1988, especially for P.

A região do Alto Jequitinhonha tem se apresentado como expressivo parque cafeeiro do estado de Minas Gerais. No entanto, têm-se pouca informação sobre a influência do estado nutricional do cafeeiro sobre a qualidade da bebida juntamente com a produção. Objetivou-se, neste trabalho, foi realizar o levantamento da qualidade da bebida do café (Coffea arabica L.) e avaliar o estado nutricional dos cafeeiros do Alto Jequitinhonha, através do DRIS. Obtiveram-se as produções, as atividades enzimáticas da polifenoloxidase dos grãos de café e os teores foliares dos nutrientes em duas safras (2005 e 2006), para o cálculo do DRIS, com vistas a efetuar o diagnóstico nutricional do cafeeiro. A região do Alto Jequitinhonha apresentou aptidão para produzir cafés de melhor qualidade (bebida "mole", "apenas mole" e "estritamente mole"), e o melhor estado nutricional das lavouras cafeeiras proporcionou produtividade de grãos de 65,0 sacas ha-1 e qualidade de bebida "mole" e "apenas mole".Coffee crops in the region of the High Jequitinhonha, State of Minas Gerais, Brazil, has become more expressive. However, there is still little information on the influence of the nutritional state of the coffee tree on the beverage quality and the yield. The objective of this work was to carry out a survey of the quality of the coffee beverage and assess the nutritional status of the High Jequitinhonha, using DRIS. Yield, polyphenyloxidase enzyme activity of the grains coffee and leaf nutrient contents were observed in two crops (2005 and 2006) for the calculation of DRIS for a diagnosis of the nutritional state of the coffee. The region of the High Jequitinhonha can produce higher quality coffee ( "soft", "barely soft" and "strictly soft" beverages), and the best nutritional status of coffee plantations produced 65.0 sacks ha-1 and beverage qualities "soft" and "barely soft."

O objetivo deste trabalho foi testar a aplicação de medidas de acurácia para determinar a utilidade de diagnósticos nutricionais para comparação de fórmulas DRIS, e avaliar o emprego dessas medidas no processo de modelagem das funções do Sistema Integrado de Diagnose e Recomendação (DRIS). Foram avaliadas três fórmulas: relações bivariadas simplificadas; relações multivariadas; e modelagem das funções DRIS. Foram utilizados dados de monitoramento nutricional de pomares de mangueiras cultivadas no Vale do São Francisco. O desempenho das fórmulas foi avaliado com base na concordância de seus diagnósticos com o proporcionado pelo método das faixas de suficiência. Foram determinadas as acurácias global e de insuficiência, de equilíbrio, de excesso, de deficiência, de suficiência e de toxicidade nutricional. A fórmula simplificada e a de relações multivariadas tiveram resultados semelhantes para as acurácias de deficiência e insuficiência, mas inferior ao da fórmula DRIS para modelagem das funções. Esta última, por possibilitar o ajuste do coeficiente de sensibilidade de cada função DRIS, mostrou-se promissora para diminuir riscos de diagnósticos falsos de deficiência (deixar de recomendar o nutriente quando ele é necessário) e de insuficiência (recomendar o nutriente quando ele não é necessário). No entanto, a fórmula DRIS para modelagem das funções não mostra desempenho satisfatório nas demais medidas de acurácia.The objective of this work was to test the application of accuracy measures to determine the usefulness of nutritional diagnosis to compare different DRIS formulas, and to evaluate the use of these measures in the DRIS function modeling process. Three DRIS formulas were evaluated: bivariate relations (simplified); multivariate relations; and DRIS function modeling. Monitoring data from commercial mango orchards grown at São Francisco River Valley, Brazil, were used. Formula performances were evaluated based on the agreement of their diagnoses with the one provided by the sufficiency range method. Global accuracy, and the ones for insufficiency, equilibrium, excess, deficiency, sufficiency and nutritional toxicity were determined. The simplified and multivariate formulas showed similar results for insufficiency and deficiency accuracies, but they had a lower performance than the DRIS function modeling formula. This latter, for allowing of the adjustment of each DRIS function sensibility coefficient, showed to be promising in reducing the risks of false diagnosis for deficiency (as for not recommend the nutrient when it is necessary) and for insufficiency (as for recommend the nutrient when it is not necessary). However, the DRIS formula for function modeling does not show a satisfactory performance for other accuracy measures.

O objetivo deste trabalho foi avaliar a performance de normas DRIS específicas ou gerais no diagnóstico do estado nutricional do cupuaçuzeiro (Theobroma grandiflorum), na Amazônia Sul-Ocidental. Amostras foliares de cupuaçu foram coletadas de 153 pomares comerciais, com idade entre 5 e 18 anos, cultivados em monocultivo ou em sistemas agroflorestais. Foram geradas normas DRIS específicas para cada sistema de produção e normas gerais, obtidas para o conjunto da população monitorada. Na obtenção das normas, foi considerada a relação nutricional entre N, P, K, Ca, Mg, Fe, Cu, Zn e Mn. A maioria das médias das relações bivariadas entre nutrientes e dos diagnósticos produzidos pelas normas DRIS específicas não diferiu em relação aos produzidos com o uso da norma DRIS genérica. Portanto, a avaliação do estado nutricional de cupuaçuzeiros pode ser realizada com o uso de normas DRIS genéricas, que independem do sistema de cultivo.The objective of this work was to evaluate the performance of specific or generic DRIS norms regarding diagnosis of the nutritional state of cupuaçu (Theobroma grandiflorum) orchards, in Southwestern Amazonia. Cupuaçu leaf samples were collected from 153 commercial orchards with ages ranging from 5 to 18 years, cultivated either in monoculture or in agroforestry systems. Specific DRIS norms, obtained for each production system, and generic norms, for the entire population, were generated. DRIS norms were obtained considering the nutritional relationship between N, P, K, Ca, Mg, Fe, Cu, Zn and Mn. The majority of bivariate relation means between nutrients and diagnostics obtained from the specific DRIS norms did not differ in comparison to the ones obtained when the generic DRIS norm was used. The evaluation of the nutritional state of cupuaçu orchards can be done using generic DRIS norms, which do not take into account the production system.

High quantities of mineral fertilizers (MF) are required for good coconut seedling production, whose up dated recommendation is 232 grams per seedling. The objective of this work was to assess the substitution of the MF by organic fertilizer as sugar-cane filter cake (SCFC) on coconut seedlings in polybag. The SCFC is an organic residue from sugar-cane manufacturing composed of various chemical elements, as for instance: nitrogen, phosphorus, potassium, calcium and magnesium. The experiment was carried out at the Itapirema Research Station, Goiana, Pernambuco State, Brazil, in a randomized complete block design, with factorial disposition 52, replicated three times, with six tall coconut seedlings per plot. The treatments were the combinations of five doses of MF (in g seedling-1): 46.25; 92.50; 138.75; 185.00 and control, using urea, simple superphosphate and potassium chloride at the proportion of 1:2:3, respectively, and five doses of SCFC (in kg polybag-1): 0.5; 1.0; 1.5; 2.0 and control. Eight months after young coconut seedlings replacement to the polybags the following parameters were measured: collar girth (CG), leaf area (LA), number of live leaves (NL) and plant height (PH). For leaf nutritional diagnosis and growing media chemical and physical analyses, samples were collected. There was significance for the two factors, individually, to all parameters. The trend analysis revealed linear, quadratic and cubic responses, according to the studied character. The mixture of 0.5 kg of SCFC polybag-1 plus 46.25 g of the MF was sufficient for obtaining seedlings of excellent quality and promoting a fertilizers economy around 80%. According to other results from this research, the number of seedlings per plot and the critical level of nutrients in the leaf of coconut seedlings should be reviewed.

O alto custo das adubações, a importância da nutrição mineral na produtividade e o nível de tecnologia adotado nas lavouras de arroz irrigado no sul do Brasil tornam relevante a utilização de técnicas de avaliação do estado nutricional, como a diagnose foliar. Entre os métodos para diagnóstico nutricional das plantas, destaca-se o Sistema Integrado de Diagnose e Recomendação (DRIS), que utiliza o conceito do balanço de nutrientes. O objetivo deste trabalho foi estabelecer normas de referência DRIS e padrões nutricionais para a cultura do arroz irrigado por inundação. Foram utilizados resultados de análise foliar e de produtividade de 356 lavouras das diferentes regiões arrozeiras do Rio Grande do Sul na safra 2005/2006. As amostragens foram feitas no estádio de florescimento da cultura. A população de alta produtividade foi determinada pela melhor correlação entre o Índice de Balanço Nutricional (IBN) e a produtividade, sendo ela a que atingiu produtividade > 9.000 kg ha-1. O cálculo das funções e índices DRIS baseou-se no método original de Beaufils. Os resultados indicaram que: a concentração dos nutrientes mostrou relação positiva com os respectivos índices DRIS; o IBN apresentou correlação negativa com a produtividade; a determinação do ponto de equilíbrio DRIS permitiu o estabelecimento de um padrão nutricional para o arroz irrigado por inundação; e o método DRIS, utilizando normas específicas para o Rio Grande do Sul, foi eficiente no diagnóstico nutricional do arroz irrigado por inundação.In view of the high cost of fertilizers and the importance of mineral nutrition on the technology level used by rice producers for yields in southern Brazil, the use of evaluation techniques of the nutritional status, such as foliar diagnosis has become essential. Among the methods for nutritional plant diagnosis, the Diagnosis and Recommendation Integrated System (DRIS) stands out, which is based on the concept of nutrient balance. The objective of this study was to establish a DRIS reference norm and nutritional standards for flooded rice. Results of foliar analysis and grain yield of 356 farms in different rice-producing regions in the 2005/2006 growing season were used. The leaf samples were collected at the flowering stage. High-yielding populations were selected based on the best correlation between the Index of Nutritional Balance (IBN) and the maximum yield, which reached a more than 9.000 kg ha-1. The calculation of the DRIS functions and indexes was based on the original method of Beaufils. Results indicated that: the nutrient concentration was positively related with the respective DRIS indexes; the IBN correlated negatively with yield; the determination of the DRIS equilibrium point allowed the establishment of nutritional standards for flooded rice; and the DRIS method, using specific norms for the Rio Grande do Sul State, was efficient for a nutritional diagnosis of flooded rice.

O objetivo do trabalho foi avaliar o efeito da adição de um concentrado zeolítico enriquecido com N, P e K ao substrato de cultivo sobre o crescimento, produção de matéria seca, área foliar, teores e extração de N, P e K e os teores de clorofila do limoeiro 'Cravo'. O porta-enxerto foi cultivado por 93 dias em tubetes de 150 cm³ com substrato orgânico compostado de casca de coco e carvão vegetal (3:1) ao qual se adicionou o concentrado zeolítico. Este foi obtido com a concentração da zeólita natural (Z) e enriquecimento desta com KNO3 (ZNK), e também com a acidificação com H3PO4 e mistura com apatita (ZP). Utilizou-se uma mistura de 30%ZNK + 70%ZP nas doses de: 0; 2,5; 5; 10 e 15 g por planta. Os resultados indicaram que o fornecimento de nutrientes através do mineral zeólita adicionado ao substrato orgânico comprovou ser alternativa viável para a obtenção de porta-enxertos no sistema de produção em ambiente protegido. A adição de 6,4 g do concentrado zeolítico enriquecido com NPK aumentou significativamente a produção de matéria seca, área foliar, altura e diâmetro de caule. Este aumento foi de 37,5% em relação à testemunha que não recebeu o concentrado zeolítico. Houve aumentos nos teores e extração de N, P e K com o fornecimento da zeólita enriquecida. As leituras dos teores de clorofila relacionaram-se com os teores de N, indicando ser esta uma alternativa para o diagnóstico do estado nutricional para a cultura.The main objective of this research was to evaluated the growth, dry matter production, leaf area, N, P and K levels and exportation and chlorophyll levels of Rangpur Lime (Citrus limonia Osbeck) grown in a substrate with NPK enriched zeolite. Rootstocks were cultivated during 93 days in 150cm³-dibble tubes containing composted organic substrate of cocopeat and vegetal coal (3:1) with zeolite addition. Treatments comprised 4 levels (0, 2.5, 5, 10 and 15 g per plant) of a NPK-enriched zeolite, which was a mix of H3PO4/apatite-zeolite (70%) and KNO3 - zeolite (30%). Results indicated that the supply of nutrients through the mineral zeolite enriched with NPK added to the organic substrate was a viable alternative for citrus rootstock production in protecting environment. The supply of 6,4 g of enriched zeolite significantly increased dry matter production, leaf area, height and steam diameter. These increases were 37,5% in relation to the control without zeolite. N, P and K foliar levels increased with zeolite enriched with NPK. Chlorophyll levels were related to N levels, pointed out to be a useful tool for Rangpur Lime nutritional status evaluation.

For Brazilian conditions there are still no studies on the use of the diagnosis and recommendation of the integrated system (DRIS) for nutritional diagnosis of the apple tree. The nutritional diagnosis of the apple tree is made using the criterion of sufficiency range. The aim of this report is to establish DRIS norms to interpret the results of apple tree leaf analysis in South Brazil. The study covered the apple producing areas of the states of Rio Grande do Sul and Santa Catarina, in 70 orchards selected for their high productivity and employment of excellent management techniques. The concentrations of nitrogen, phosphorus, potassium, calcium, magnesium, boron, copper, iron, manganese, and zinc were determined in leaf samples. DRIS indices were calculated using two criteria for the choice of the ratio order of nutrients (F value - ratio of the variance of the relationships among nutrients between the reference group and the low productivity group, and R value - correlation coefficients between the productivity values and the relationship between pairs of nutrients) and three forms to calculate the nutrient functions (methods of Beaufils, Jones and Elwali & Gascho). The two criteria for the choice of the ratio order of the nutrients selected different ratios. The concentrations of nutrients presented positive correlations (P < 0.01) with the respective indices DRIS, except for N. The defined DRIS norms are applicable for the nutritional diagnosis of apple trees.Para as condições brasileiras, ainda não existem estudos sobre a utilização do sistema integrado de diagnose e recomendação (DRIS) para a diagnose nutricional da macieira, cujo diagnóstico nutricional das plantas é feito utilizando o critério de faixa de suficiência. Este trabalho teve por objetivo estabelecer normas DRIS, visando à interpretação dos resultados de análises de folhas de plantas de macieira no Sul do Brasil. O estudo foi realizado nas regiões produtoras de maçã do Rio Grande do Sul e de Santa Catarina, em 70 pomares selecionados quanto à produtividade e técnicas de manejo do pomar. Foram determinadas as concentrações de nitrogênio, fósforo, potássio, cálcio, magnésio, boro, cobre, ferro, manganês e zinco nas amostras de folhas. Os índices DRIS foram calculados utilizando-se dois critérios para a escolha da ordem da razão dos nutrientes (valor "F" - razão de variância das relações entre nutrientes entre o grupo de referência e de baixa produtividade e valor "R" - coeficientes de correlação entre os valores de produtividade e a relação entre os pares de nutrientes) e três formas de cálculo das funções dos nutrientes (métodos de Beaufils, Jones e Elwali & Gascho). Os dois critérios para a escolha da ordem da razão dos nutrientes selecionaram razões diferentes. As concentrações dos nutrientes apresentaram correlações positivas (P < 0,01) com os respectivos índices DRIS, com exceção do N. As normas DRIS definidas são aplicáveis para o diagnóstico nutricional da macieira.

To evaluate three procedures of the calculation of DRIS indices, as well as the efficiency of DRIS as a method for the interpretation of apple tree leaf analyses. This study uses data collected in apple producing areas of the Rio Grande do Sul and Santa Catarina States, Brazil. The concentrations of nitrogen, phosphorus, potassium, calcium, magnesium, boron, copper, iron, manganese, and zinc were determined in the leaf samples. The validation of the DRIS method used results of an experiment of potassium fertilization. The DRIS indices were calculated using two criteria for the choice of the ratio order of nutrients (F value ratio of variance of the relationships among nutrients between the reference group and the low productivity group, and R value - correlation coefficients between the productivity and the relationship between pairs of nutrients) and three forms of calculation of nutrient functions (methods of Beaufils, Jones and Elwali & Gascho). The Nutritional Balance Index (NBI) presented negative correlation with the productivity in all combinations. The DRIS method described by Elwali & Gascho, using the F value, presented a performance similar to the criterion of sufficiency range, and it can be used for the interpretation of foliar analysis of apple trees, because it presents values of the nutritional balance index that indicates the nutritional status of the plants, and for the efficiency in the nutritional diagnosis of the crop.Este trabalho teve por objetivo avaliar três procedimentos de cálculo dos índices DRIS, bem como avaliar a eficiência do DRIS como método de interpretação de resultados de análises de folhas de plantas de macieira. O estudo foi realizado nas regiões produtoras de maçã do Rio Grande do Sul e de Santa Catarina. Foram determinadas as concentrações de nitrogênio, fósforo, potássio, cálcio, magnésio, boro, cobre, ferro, manganês e zinco nas amostras de folhas. A validação do método DRIS utilizou resultados de um experimento de adubação potássica. Os índices DRIS foram calculados utilizando-se dois critérios para a escolha da ordem da razão dos nutrientes (valor "F" - razão de variância das relações entre nutrientes entre o grupo de referência e de baixa produtividade e valor "R" - coeficientes de correlação entre os valores de produtividade e a relação entre os pares de nutrientes) e três formas de cálculo das funções dos nutrientes (métodos de Beaufils, Jones e Elwali & Gascho). O Índice de Balanço Nutricional (IBN) apresentou correlação negativa e significativa com a produtividade em todas as combinações de métodos testados. O método DRIS descrito por Elwali & Gascho, utilizando o "valor F", apresentou desempenho semelhante ao critério de faixa de suficiência e pode ser utilizado para a interpretação da análise foliar em macieira, por apresentar valores de IBN que indicam o estado nutricional das plantas e pela eficiência no diagnóstico nutricional da cultura.

Diversos estudos têm demonstrado o uso promissor de métodos de diagnose nutricional para definição de teores ótimos e níveis críticos de nutrientes em tecidos vegetais. Nesse sentido, o objetivo deste trabalho foi comparar os teores ótimos de nutrientes para soja, estimados por meio dos métodos Chance Matemática (ChM), Sistema Integrado de Diagnose e Recomendação (DRIS) e Diagnose da Composição Nutricional (CND), a partir de dados provenientes de monitoramento nutricional de 111 lavouras comerciais de soja, da região sul do Estado de Mato Grosso do Sul. Os teores ótimos de nutrientes estimados pelos métodos DRIS e CND foram idênticos ao teor médio observado na população de referência. Para o método ChM, exceto para os nutrientes Cu, Fe, Mn e Zn, os teores ótimos estimados também foram idênticos ou muito próximos ao teor médio na população de referência. Os métodos ChM, DRIS e CND mostraram-se promissores na calibração de teores ótimos para a cultura da soja a partir de dados provenientes de monitoramentos nutricionais de lavouras comerciais.Several studies pointed out the promising use of nutritional diagnosis methods for the determination of optimum nutrient contents and critical levels in plant tissues. Thus, the objective of this study was to compare the optimum nutrient content for soybean, estimated by the Mathematical Chance (ChM), Diagnosis and Recommendation Integrated System (DRIS) and Compositional Nutrient Diagnosis (CND) methods. The optimum nutrient contents estimated by DRIS and CND where identical to the mean content in the reference population. Apart from the nutrients Cu, Fe, Mn and Zn, the optimum contents were also equal or in close proximity to the mean nutrient contents of the reference population by the ChM method. The ChM, DRIS and CND methods proved promising for the calibration of optimal nutrient contents for soybean based on data obtained from nutrient monitoring of commercial fields.

O objetivo deste trabalho foi modelar o fator k e as funções DRIS para a diagnose foliar de mangueiras cultivadas. Dez pomares comerciais, no estágio de produção, localizados no vale do Rio São Francisco, foram monitorados, mensalmente, durante dois anos, por meio da coleta de amostras foliares para determinação dos teores de N, P, K, Ca, Mg, B, Fe, Mn, Zn e Cu. Os dados foram testados quanto à normalidade e as relações entre as concentrações dos nutrientes foram usadas para calcular as normas DRIS, obtendo-se média, variância e limites máximo e mínimo de cada relação dentro da população amostrada. Os nutrientes foram classificados como macronutrientes de resposta freqüente (MAF) (N, P e K), macronutrientes de resposta rara (MAR) (Ca e Mg); micronutrientes de resposta freqüente (MIF) (B, Fe, Mn e Zn) e, micronutrientes de resposta rara (MIR) (Cu). Funções DRIS foram desenvolvidas para cada classe de nutrientes. O modelo desenvolvido expressa o balanço nutricional das plantas cultivadas ajustado a cada nutriente e reflete o comportamento biológico das plantas como resultado da variação da disponibilidade dos nutrientes.The objective of this work was to model DRIS functions and k factor on foliar diagnosis of mango crops. Ten commercial orchards, at yield stage, in the São Francisco River valley were monitored, monthly, during a two-year period, by means of collecting leaf samples to determine N, P, K, Ca, Mg, B, Fe, Mn, Zn and Cu concentrations. Data were tested for normality and bivariate relationships between nutrient concentrations were used to calculate DRIS norms. Mean, variance as well as minimum and maximum values were calculated for each relationship within the population. Nutrients were classified as follows: highly responsive macronutrients (HRMa) (N, P and K); rarely responsive macronutrients (RRMa) (Ca and Mg); highly responsive micronutrients (HRMi) (B, Fe, Mn and Zn), and rarely responsive micronutrients (RRMi) (Cu). DRIS functions were developed for each nutrient class. Results showed that the developed model expresses the nutritional balance adjusted for each nutrient, and reflects the expected biological behavior of plants as a result of variation in the availability of nutrients.

O objetivo deste trabalho foi comparar os diagnósticos do estado nutricional de um conjunto de 111 lavouras comerciais de soja, pelos métodos: Sistema Integrado de Diagnose e Recomendação (DRIS) e Diagnose da Composição Nutricional (CND), com uso do conceito de potencial de resposta à adubação. Nas lavouras analisadas, observou-se que Zn, P e Fe foram os nutrientes diagnosticados por ambos os métodos como os mais limitantes pela ausência, e Mg e Mn os mais limitantes por excesso. A freqüência de lavouras com diagnósticos concordantes, quanto ao potencial de resposta à adubação, foi maior para os nutrientes considerados de maior deficiência relativa (90,3%), em relação aos considerados de maior excesso relativo (81,9%). Quando se avaliaram os diagnósticos concordantes quanto ao estado nutricional, a freqüência variou de 85,9% para o P a 98,6% para o Mn. Os métodos DRIS e CND tendem a ser concordantes quanto ao diagnóstico nutricional; o agrupamento de classes de potencial de resposta à adubação pode resultar no agrupamento, em uma única classe de estado nutricional, os nutrientes com alta e baixa probabilidade de resposta à adubação.The objetive of of this work was to compare the diagnostics of the nutritional state of a group of 111 commercial soybean plantations, obtained by Diagnosis and Recommendation Integrated System (DRIS) and Compositional Nutrient Diagnosis (CND) methods applying the response potencial to fertilization concept. It was observed that zinc, phosphorus and iron were the nutrients diagnosed by both methods as the more restrictive for lack, and magnesium and manganese the more restrictive for excess. Agreement between DRIS and CND diagnoses was higher for nutrients considered of greater relative deficiency (90.3%) than for those considered of greater relative excess (81.9%). When the classes of nutritional state were evaluated, the frequency of plantations with concordant diagnosis varied from 85.9% for phosphorus to 98.6% for manganese. DRIS and CND methods tend to be consonants about nutritional status diagnoses; classes grouping of potential response to fertilization may result in grouping in one class of nutritional state nutrients with high and low probability of response.

Este trabalho teve o objetivo de avaliar, por meio da análise foliar, as limitações nutricionais para produção de mudas de mangostãozeiro. Após 12 meses do plantio, em condições de viveiro, com sombreamento no início do desenvolvimento, foi observado amarelecimento progressivo das folhas novas, com diminuição significativa dos teores foliares de Fe e Mn. A aplicação de sulfato de manganês (0,8 mg L-1 de Mn) + 2,5 g L-1 de uréia, via foliar, não ocasionou recuperação da tonalidade verde do limbo foliar. Entretanto, com sulfato de ferro, na concentração de 0,8 mg L-1 de Fe + 2,5 g L-1 de uréia, houve aumento da pigmentação verde nas folhas, o que mostra a baixa eficiência do mangostãozeiro na absorção de Fe, apesar da alta concentração desse nutriente no terriço (223,7 mg dm-3). Isto indica a necessidade de aplicação suplementar de Fe, no substrato ou nas folhas, na fase de viveiro do mangostãozeiro.This work had the objective to evaluate, by foliar analysis, the nutritional limitations to the production of mangosteen seedlings. After 12 months in the nursery, under shade in the initial development, a progressive yellowing of the young leaves was observed, together with significant reduction of Fe and Mn concentrations in the leaf. Foliar sprays of Mn 0.8 mg L-1 as MnSO4 plus 2.5 g L-1 of urea was ineffective to recover green color of the leaf blades. However, this was achieved with application of Fe 0.8 mg L-1, as FeSO4, plus 2.5 g L-1 of urea, with increase of regreening, which highlights the low Fe absorption efficiency of mangosteen, despite the high concentration of this nutrient in the substrate of surface soil (223.7 mg dm-3). This indicates the need of application of Fe in the substrate or on the leaves, during the nursery stage of mangosteen.

The Diagnosis and Recommendation Integrated System (DRIS) has been proved efficient as a method for nutritional diagnosis in several crops. However there is a lack of information on the use of DRIS for tropical forage grass. The aim of this paper was to establish norms for interpretation of results of analysis from recently expanded leaf laminae of Brachiaria decumbens Stapf. (Signal grass), through the DRIS method. To establish DRIS norms, concentrations of N, P, K, Ca, Mg, S, Cu, Fe, Mn, and Zn and the relative production obtained in six experiments conducted in greenhouse using nutrient solution and silica as substrate were considered. DRIS indices were calculated using two criteria in order to choose the ratio order of nutrients: F value - ratio of variance for the relationships among nutrients between the reference group and the low productivity group; and R value - correlation coefficients between the productivity values and the relationship among the pairs of nutrients, and three forms of calculation for the functions of nutrients (methods of Beaufils, of Jones, and of Elwali & Gascho). The two criteria to choose the ratio order of nutrients selected different ratios between pairs of nutrients; the nutrient concentrations were positively and significantly correlated with the respective DRIS indices, except for N; and DRIS norms are useful for the nutritional diagnosis of the ten studied nutrients in leaf laminae of Signal grass.

The Diagnosis and Recommendation Integrated System (DRIS) allows the interpretation of results of leaf analysis through relationships among nutrients, instead of the absolute and isolated concentration of each one, as it is used by the criterion of sufficiency range. The objective was to evaluate three procedures of calculation of DRIS indices, and to verify the efficiency of DRIS as interpretation method for the results of Brachiaria decumbens (Signal grass). The study was developed with the results of six experiments carried out in a greenhouse at Piracicaba, SP, with nutrient solution. Concentrations of N, P, K, Ca, Mg, S, Cu, Fe, Mn, and Zn were used in the samples of recently expanded leaf laminae of the grass. The validation of the DRIS method used results from an experiment with nitrogen and sulfur rates applied to the same grass from the Mundo Novo farm, Brotas, SP. DRIS indices were calculated according to two criteria to choose the ratio order of nutrients (F value and R value) and three ways to calculate the nutrient functions (methods of Beaufils, Jones, and Elwali & Gascho). Nutritional Balance Index (NBI), calculated according to the generated norms, presented negative and significant correlation coefficients with the productivity in the combinations of methods tested and DRIS methods proposed by Beaufils, Jones and Elwali & Gascho were efficient in detecting concentrations that show nutrients deficiency or excess.O Sistema Integrado de Diagnose e Recomendação (DRIS) permite a interpretação dos resultados de análise foliar, utilizando relações entre nutrientes, ao invés da concentração absoluta e isolada de cada um deles, utilizada pelo critério de faixa de suficiência. Objetivou-se avaliar três procedimentos de cálculo dos índices DRIS, bem como verificar a eficiência do DRIS como método de interpretação de resultados de análises de folhas da Brachiaria decumbens (capim-Braquiária). O estudo foi desenvolvido com os resultados de seis experimentos realizados em casa-de-vegetação em Piracicaba, SP, com solução nutritiva. Foram empregadas as concentrações de N, P, K, Ca, Mg, S, Cu, Fe, Mn e Zn nas amostras de lâminas foliares recém-expandidas do capim. Para a validação do método DRIS foram utilizados resultados de um experimento com aplicação de doses de nitrogênio e enxofre realizado com o mesmo capim proveniente da Fazenda Mundo Novo, em Brotas, SP. Os índices DRIS foram calculados por dois critérios para escolha da ordem da razão dos nutrientes (valor F e valor R) e três formas de cálculo das funções dos nutrientes (métodos de Beaufils, Jones e Elwali & Gascho). O Índice de Balanço Nutricional (IBN), calculado a partir das normas geradas, apresentou coeficientes de correlação negativos e significativos com a produtividade nas combinações de métodos testados e os métodos DRIS propostos por Beaufils, Jones e Elwali & Gascho foram eficientes em detectar concentrações que revelam a deficiência ou o excesso dos nutrientes.

The Diagnosis and Recommendation Integrated System (DRIS) allows the interpretation of results of leaf analysis through relationships among nutrients, instead of the absolute and isolated concentration of each one, as it is used by the criterion of sufficiency range. The objective was to evaluate three procedures of calculation of DRIS indices, and to verify the efficiency of DRIS as interpretation method for the results of Brachiaria decumbens (Signal grass). The study was developed with the results of six experiments carried out in a greenhouse at Piracicaba, SP, with nutrient solution. Concentrations of N, P, K, Ca, Mg, S, Cu, Fe, Mn, and Zn were used in the samples of recently expanded leaf laminae of the grass. The validation of the DRIS method used results from an experiment with nitrogen and sulfur rates applied to the same grass from the Mundo Novo farm, Brotas, SP. DRIS indices were calculated according to two criteria to choose the ratio order of nutrients (F value and R value) and three ways to calculate the nutrient functions (methods of Beaufils, Jones, and Elwali & Gascho). Nutritional Balance Index (NBI), calculated according to the generated norms, presented negative and significant correlation coefficients with the productivity in the combinations of methods tested and DRIS methods proposed by Beaufils, Jones and Elwali & Gascho were efficient in detecting concentrations that show nutrients deficiency or excess.

Dois experimentos conduzidos em solução nutritiva tiveram como objetivo avaliar os efeitos de doses de boro e de manganês no crescimento e na composição mineral de folhas de mudas de goiabeira (Psidium guajava L.). No experimento com boro, foram testadas sete doses (0, 0,125, 0,25, 0,5, 1,0, 1,5 e 3,0 mg L-1). Pelos resultados, verificou-se que a necrose marginal e as manchas circulares púrpuras e esparsas no limbo foliar foram os principais sintomas de toxidez apresentados, sendo esses associados com a dose máxima e com um teor foliar de 146 mg kg-1. Análises de tecidos foliares sem e com necroses mostraram teores de 92 e 720 mg kg-1, respectivamente. Somente a produção de matéria seca de raízes e o teor foliar de fósforo e enxofre foram afetados significativamente pelas doses de B. Para o manganês, foram usadas sete doses (0, 0,5, 10, 20, 30, 40 e 50 mg L-1). A produção de matéria seca total e os teores foliares de Ca, Mg e Fe foram afetados pelas doses de Mn. Os sintomas foliares de toxidez evidenciaram-se em salpicos adensados de minúsculas pontuações escuras nas folhas velhas; folhas novas de dimensões menores, cloróticas e com reticulado verde das nervuras; formação de pontuações circulares castanhas espalhadas ou fundidas ao longo ou entre as nervuras.Two experiments were carried out in nutrient solution in order to evaluate the effects of boron and manganese on growth and mineral composition of young guava seedling (Psidium guajava L.). The treatments with boron consisted of seven levels: 0, 0.125, 0.25, 0.5, 1.0, 1.5 and 3.0 mg L-1. Tip and marginal necrosis, and purple circular spots on the blade were the main observed symptoms associated with leaf boron concentration of 146 mg kg-1. Analysis of leaf tissues with and without necrosis showed boron content of 92 and 720 mg kg-1, respectively. Boron levels affected only dry matter roots, phosphorus, and sulfur concentration. The experiment with manganese used of seven levels: 0.0, 0.50, 10.0, 20.0, 30.0, 40.0 e 50.0 mg L-1. Total dry matter production, Ca, Mg and Fe contents were affected by manganese. The toxicity symptoms became evident as dense sprinkles of minuscule dark spots in old leaves; young leaves of reduced size, chlorotic and green reticulate in the veins; formation of circular brown, and punctuations spread along or between the veins.

Diagnosis and Recommendation Integrated System (DRIS) applies nutrient ratios instead of the isolated concentration values of each nutrient in interpretation of tissue analysis. The objectives of this research were to establish adequate DRIS norms for 'Valencia' sweet orange irrigated commercial groves budded on three rootstocks and correlate indexes of nutrition balance with yield. Experiments were conducted in São Paulo State, Brazil. Rootstocks Rangpur lime, Caipira sweet orange, and Poncirus trifoliata, with more than six years old and yield above 40 ton ha-1 were utilized. Data referred to yield, tree spacing, rootstock and foliar concentrations of N, P, K, Ca, Mg, S, Fe, Mn, Cu, Zn, and B in non fruiting terminals for each grove were processed for the years 1994 through 1998. DRIS indexes were calculated by Nick criterion for choosing the ratio order of the nutrients and Jones calculation method of the ratio functions. Indexes of nutritional balance calculated from DRIS norms presented high correlation with yield for the three scion/rootstock combinations. DRIS norms defined in this research are valid, since leaf sampling is done on non fruiting terminals and the grove is irrigated.O sistema integrado de diagnose e recomendação (DRIS - Diagnosis and Recommendation Integrated System) utiliza relações entre nutrientes em vez da concentração absoluta e isolada de cada um deles na interpretação da análise de tecidos. O objetivo deste trabalho foi estabelecer normas para o método DRIS em pomares comerciais irrigados de laranjeira 'Valência' sobre três porta-enxertos e correlacionar os índices de balanço nutricional com a produtividade. Os experimentos foram conduzidos no Estado de São Paulo, com os porta-enxertos limão 'Cravo', laranja 'Caipira' e Poncirus trifoliata, com mais de seis anos, e produtividade acima de 40 t ha-1. Dados de produtividade, espaçamento, porta-enxerto e teores foliares de N, P, K, Ca, Mg, S, Fe, Mn, Cu, Zn e B em ramos não frutíferos, de cada talhão, de 1994 a 1998, foram processados. A escolha da ordem da razão dos nutrientes foi determinada segundo o método Nick, e as funções das razões dos nutrientes foram calculadas de acordo com o método Jones. Os índices de balanço nutricional calculados por meio das normas geradas apresentaram alta correlação com produtividade nas três combinações enxerto/porta-enxerto. As normas DRIS definidas são aplicáveis desde que a amostragem de folhas seja realizada em ramos não frutíferos e os pomares sejam irrigados.

O sistema integrado de diagnose e recomendação DRIS (Diagnosis and Recommendation Integrated System) tem sido uma boa alternativa para a avaliação do estado nutricional de diversas culturas. O objetivo deste trabalho foi calcular índices DRIS mediante o uso de três métodos (Beaufils, Elwali & Gascho e Jones) de cálculo das funções das razões dos nutrientes e de dois critérios (Letzch e Nick) para a escolha da ordem da razão dos nutrientes, em pomares comerciais irrigados de laranjeira 'Valência'. Informações sobre a produtividade, porta-enxerto e teor de N, P, K, Ca, Mg, S, Fe, Mn, Cu, Zn e B em folhas de ramos não-frutíferos de cada talhão foram processadas nos anos de 1994 a 1998. O índice de balanço nutricional (IBN) foi calculado pela média da soma dos valores em módulo dos índices nutricionais e do índice de matéria seca. Os índices DRIS e IBN foram calculados e os valores de r² (produtividade em função de IBN) foram obtidos para cada método. O método Jones para cálculo do DRIS apresentou melhor correlação com a produtividade, e o critério Nick mostrou-se mais eficiente na escolha da ordem da razão dos nutrientes. Populações específicas, com pequeno número de observações, padronizadas quanto ao porta-enxerto e referentes a um ou dois anos de amostragem foliar e produção foram bancos de dados eficientes para a obtenção das normas DRIS.Diagnosis and Recommendation Integrated System (DRIS) has been a useful tool for nutrient diagnosis of several crops. This research aimed to establish adequate norms for DRIS through three methods (Beaufils, Elwali & Gascho and Jones) to calculate ratio functions and two criteria (Letzsch and Nick) for choosing the ratio order of the nutrients for 'Valencia' sweet orange budded on three rootstocks, in Mogi Guaçú, SP, Brazil. Data referred to yield, rootstock and concentrations of N, P, K, Ca, Mg, S, Fe, Mn, Cu, Zn and B in leaves of non fruiting terminals, for each plot, were processed for 1994 through 1998. Nutritional Balance Index (NBI) was calculated by the average of the sum (disregarding the sign) of all nutritional index values and dry matter index. DRIS and NBI indexes were calculated and the r² values (yield related to NBI) were obtained for each calculation method. DRIS calculation method of the ratio function, recommended by Jones, presented better correlation with yield. The criterion for choosing the ratio order of the nutrients recommended by Nick was more efficient. Specific populations, with reduced number of observations, standardized by rootstock and referred to one or two sampling years were more efficient data for calculation of DRIS norms.

The Valencia orange orchards established on soils of low fertility in the Northwest region of Paraná State, Brazil, have showed symptoms of Mg deficiency and reduced fruit yields. The objective of this study was to verify the relationship between yield with soil and leaf nutrients during 1996/97 growing season. Two sites of low and high productivity were selected in seven orchards. Leaf and soil samples (fertilized rows and interrows) were collected in 1996. The results showed that the citrus yields were negatively related with soil Mg/K and Ca+Mg/K ratios in the fertilized rows, and fruit weight positively correlated with leaf Zn in the low productivity orchards. The fruit weight was positively related with leaf Ca and soil Ca in the fertilized rows of the high productivity orchards. The results suggested an adequate lime and K fertilization managements in the fertilized rows, as well as an adequate Zn supply.Os pomares de laranja Valência (Citrus sinensis (L.) Osbeck) estabelecidos em solos de baixa fertilidade da região noroeste do Paraná, tem apresentado sintomas de desequilíbrio nutricional, principalmente deficiência de Mg e redução da produção e do tamanho dos frutos. O objetivo deste trabalho foi verificar as relações da produção e peso dos frutos com os nutrientes das folhas e do solo de sete pomares de laranja Valência na safra de 1996/97, em talhões de produtividade inferior e superior. Em 1996, foram coletadas amostras de folha e de solo nas faixas de adubação e nas entrelinhas. Os resultados mostraram que a produção de frutos correlacionou-se negativamente com as relações dos cátions Mg/K e Ca+Mg/K do solo das faixas de adubação dos pomares de baixa produtividade e, o peso dos frutos, correlacionou-se positivamente com os teores foliares de Zn. Nos pomares de produtividade superior, o peso dos frutos correlacionou-se positivamente com os teores de Ca das folhas e do solo nas faixas de adubação. Estes resultados sugerem um manejo adequado da calagem e da adubação potássica nas faixas de adubação dos pomares de baixa produtividade e um adequado suprimento de Zn.

With the aim of establishing critical ranges for the leaf nitrogen (N) and potassium (K) levels in fertigated coffee crops under production, an experiment was carried out in the experimental area of the Sector for Coffee Cultivation of the Department of Agriculture at the Federal University of Lavras, in Brazil. Treatments consisted of five levels of fertilizer applied through fertigation: 30%, 80%, 130%, 180% and 230% of the recommended amounts of N and K for rainfed coffee grown in Minas Gerais. A randomised block design with four replications was used. Critical ranges for nutrient concentrations in the leaves were established from the results of growth characteristics (plant height and stem diameter), leaf analyses and productivity. The results obtained were: a) nitrogen (g kg-1): 32.39 to 32.40 for January/February; 33.60 to 33.61 for March/April; 27.39 to 27.42 for May/June; 24.23 to 24.24 for July/August; 26.06 to 26.09 for September/October and 26.50 to 26.51 for November/December; b ) potassium (g kg-1): 20.08 to 20.14 for January/February; 17.89 to 17.91 for March/April; 15.93 to 15.96 for May/June; 15.29 to 15.35 for July/August; 16.61 to 16.64 for September/October and 20.58 to 20.64 for November/December.

ABSTRACT: Atemoya, an interspecific hybrid belonging to Annonaceae family, is the outcome of a cross between cherimoya (Annona cherimola Mill.) and Custard apple (Annona squamosa L.). In light of the current shortage of scientific data on the nutritional management techniques for this fruit, the need to develop and apply a specific methodology becomes crucial. From the variety of plant diagnostic tools available, the DRIS method was selected, for use in the commercial cultivation of the ‘Thompson’ cultivar of atemoya located in the São Paulo State, municipalities of Itapetininga, Piedade, Pilar do Sul and Salto de Pirapora. Normal nutrient ranges were determined to interpret the levels of N, P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn in the culture through statistical regression analysis and samples of leaf dry matter, with their respective DRIS indices. Although the general index of the nutritional balance of DRIS disallowed establishing a link with productivity, this study achieved it based on the standard of determining normal ranges for cognate macronutrients to the ones cited in the literature.