Abstract Studies evaluating the influence of nutrients on plant anatomy are very important because nutritional deficiencies can alter the thickness and shape of certain tissues, compromising their functionality what can explain the reduction of productivity. The aim of this study was to characterize the anatomical changes in cherry tomato plants subjected to calcium (Ca) and magnesium (Mg) deficiencies. The experiment was conducted in nutrient solution and the plants subjected to three treatments: complete solution (Control), Ca restriction (1 mmol L-1 of Ca) and Mg omission (without Mg). The experimental design was completely randomized, with three repetitions. Sixty days after seedling transplanting leaves and stem were collected and submitted to anatomical evaluations. Ca or Mg deficiency promotes most evident anatomical changes in chlorophyllous and vascular tissues of the leaves, rather than in the stems. Leaves of ‘Sindy’ tomato plants with a concentration of 1.7 g kg-1 of Mg and visual symptoms of Mg deficiency present hyperplasia of both tissues, phloem and xylem. This deficiency also promotes increases in the thickness of mesophyll, spongy parenchyma and palisade parenchyma, and consequently of leaf thickness. The midrib of the leaves with a concentration of 10 g kg-1 of Ca, without visual symptoms of deficiency presented phloem hypertrophy and hyperplasia.

Resumo As cultivares de repolho utilizadas atualmente têm alto potencial produtivo e podem apresentar diferenças na absorção e utilização de nutrientes. Dessa forma, pesquisas com a quantificação do crescimento das plantas e da acumulação de nutrientes são básicas para melhorar a eficiência de fertilização do solo e otimizar a produção. Objetivou-se, com este trabalho, determinar as curvas de acúmulo de matéria seca (MS) e de nutrientes (N, P, K, Ca, Mg, S, Cu, Fe, Mn e Zn) por cultivares de repolho em duas épocas de cultivo. No verão-outono foram utilizadas as cultivares ‘Astrus Plus’ e ‘Green Valley’, e no outono-inverno, ‘Astrus Plus’ e ‘Fênix’. As plantas foram amostradas, após o transplante, em intervalos de 10 dias até a colheita. O acúmulo de matéria seca e de nutrientes é variável com a época de cultivo e com a cultivar. As maiores taxas de acúmulo de matéria seca e de nutrientes ocorrem nos 10 últimos dias do ciclo. As adubações com N, P, K, Fe e Zn devem receber maior atenção em razão de apresentarem os maiores índices de colheita.

Abstract Cabbage cultivars currently cultivated present high yield potential and may present differences regarding absorption and use of nutrients. Thus, studies quantifying plant growth and nutrient accumulation are the basis to improve fertilization efficiency and optimize yield. This study aimed to determine the dry matter and nutrient (N, P, K, Ca, Mg, S, Cu, Fe, Mn, and Zn) accumulation curve of cabbage cultivars during two growing seasons. Cultivars Astrus Plus and Green Valley were cultivated during summer-autumn crop season, while Astrus Plus and Fênix during the autumn-winter crop season. Plants were sampled after transplanting at 10-day intervals until harvest. Dry matter and nutrient accumulations are variable with growing season and cultivar. The highest dry matter and nutrient accumulation rates occur in the last ten days of the cycle. Fertilizations with N, P, K, Fe, and Zn should receive more attention due to higher harvest indices.

Resumo: O objetivo deste trabalho foi avaliar o efeito do cobre na composição química dos grãos de café e na qualidade da bebida, bem como relacionar ambas aos teores foliares de Cu do cafeeiro (Coffea arabica). Cultivaram-se cafeeiros em sistema hidropônico com 0,2, 0,4, 0,8, 1,6 e 3,2 μmol L-1 de Cu até a produção de frutos. Avaliou-se a produção do café, e, após secagem dos grãos maduros, determinaram-se: a concentração foliar de cobre; a acidez total titulável; o índice de coloração; a condutividade elétrica; o K lixiviado; a atividade da polifenoloxidase (PPO); as concentrações de cafeína, trigonelina, ácidos orgânicos, fenóis totais, ácidos clorogênicos (3-CQA, 4-CQA e 5CQA), sacarose, glicose, arabinose, manose e galactose; e a qualidade sensorial dos grãos torrados. O Cu aumentou a produção de grãos, a atividade de PPO e as concentrações de ácidos orgânicos, 3-CQA, sacarose e arabinose. A acidez total titulável, os fenóis totais e o 4-CQA e o 5-CQA foram reduzidos com o incremento das doses de Cu. Os teores foliares relacionados aos valores máximos e mínimos dos atributos de qualidade desejáveis e indesejáveis variaram de 5,6 a 11,4 mg kg -1 de Cu, respectivamente. O cobre afeta a produção e a composição química dos grãos de café, e os atributos relacionados à qualidade são maximizados com baixas concentrações foliares do nutriente.

Abstract: The objective of this work was to evaluate the effect of copper on the chemical composition of coffee beans and on the quality of the beverage, relating both of them to the Cu leaf contents in coffee (Coffea arabica) plants. Coffee plants were grown in a hydroponic system containing 0.2, 0.4, 0.8, 1.6, and 3.2 μmol L-1 Cu until fruit setting. Coffee bean production was evaluated, and, after the cherries were dried, the following characteristics were determined: leaf Cu content; total titratable acidity; color index; electrical conductivity; leached K; polyphenol oxidase (PPO) activity; concentrations of caffeine, trigonelline, organic acids, total phenols, chlorogenic acids (3-CQA, 4-CQA, and 5-CQA), sucrose, glucose, arabinose, mannose, and galactose; and sensory quality of roasted beans. Cu increased bean yield, PPO activity, and the concentrations of organic acids, 3-CQA, sucrose, and arabinose. Total titratable acidity, total phenols, 4-CQA, and 5-CQA were reduced with increasing Cu doses. Leaf contents related to the maximum and minimum values of desirable and undesirable quality attributes ranged from 5.6 to 11.4 mg kg-1 Cu, respectively. Copper affects the production and chemical composition of coffee beans, and the attributes related to quality are maximized in plants with low leaf contents of the nutrient.

RESUMO A cenoura está entre as principais olerícolas consumidas no Brasil, onde as cultivares utilizadas atualmente apresentam elevado potencial produtivo e demanda nutricional, o que exige constantes ajustes dos programas de fertilização da cultura. Objetivou-se determinar valores de referência e índices diagnósticos pelo método DRIS para três fases fenológicas da cultura da cenoura (cerca de 40 e 70 dias após a semeadura e na colheita), bem como verificar a possibilidade de diagnose precoce de limitação nutricional. Para determinação das normas DRIS, obteve-se um banco de dados a partir da amostragem de folhas, produtividade de raízes e teores foliares de N, P, K, Ca, Mg, S, B, Cu, Mn e Zn, em lavouras comerciais de cenoura. A ordem de limitação nutricional foi gerada em função do potencial de resposta à adubação e da faixa ótima dos teores foliares. Os valores referência de K, Ca, Mg, S e Mn mostraram-se semelhantes em todas épocas de amostragem. Os de N, P, B, Cu e Zn variaram, reforçando a ideia de padronização da época de amostragem para esses nutrientes. O Mn, K e Mg foram os nutrientes mais limitantes por deficiência, enquanto Zn e B foram os menos limitantes. Para K, Ca, Mg, S e Mn, há concordância entre a diagnose realizada nas fases precoces e a efetuada na colheita, o que indica possibilidade de diagnose precoce da limitação desses nutrientes.

ABSTRACT Carrot is one of the most consumed vegetables in Brazil, where the cultivars currently grown present a high yield potential and nutritional demand, which require constant adjustments in fertilization programs for the crop. This study aimed at determining reference values and diagnostic indices by using the DRIS method in three phenological stages of the carrot crop (around 40 and 70 days after sowing and at harvest), as well as evaluating the possibility of early diagnosis for nutritional limitations. For determining the DRIS norms, a database was obtained from leaf samplings, root yields and leaf contents of N, P, K, Ca, Mg, S, B, Cu, Mn and Zn, in carrot commercial fields. The nutritional limitation order was generated as a function of the fertilization response and optimum range of leaf contents. The reference values for K, Ca, Mg, S and Mn were similar in all sampling times. N, P, B, Cu and Zn varied with the stages sampled, indicating the need to standardize the sampling times for these nutrients. Mn, K and Mg were the most limiting nutrients for the crop growth, while Zn and B were the least limiting. There was a correlation between the diagnoses performed at early stages and those performed at harvest for K, Ca, Mg, S and Mn, indicating the possibility of early diagnosis for the deficiency of these nutrients.

RESUMO Objetivou-se com este trabalho avaliar a eficiência de recuperação de nitrogênio (N), fósforo (P) e potássio (K) pela cultura da cenoura. Foram implantados dois experimentos em área de cultivo localizada em Rio Paranaíba - MG. A cultivar "Juliana" foi semeada no período de verão e a cultivar "Nayarit" no período do inverno. Os tratamentos consistiram de seis combinações de fertilizações N-P2O5-K2O (kg ha-1): sem N (0-500-450), sem P (100-0-450), sem K (100-500-0), padrão (100-500-450), maior que o padrão (100-700-600) e menor que a padrão (100-300-300). A colheita foi realizada quando a maior parte das raízes apresentavam-se dentro do padrão comercial mais aceito pelos consumidores. Quantificaram-se as matérias fresca e seca das raízes e das folhas e com base na matéria fresca de raízes calculou-se a produtividade. Determinaram-se os teores de N, P e K em folhas e raízes por ocasião da colheita e com bases nesses teores e na matéria seca de raízes e de folhas determinaram-se a absorção e a exportação de nutrientes. As fertilizações testadas influenciaram a produtividade comercial de ambas as cultivares. A omissão da fertilização com N, com P ou com K reduziu a produtividade da cultivar "Juliana". Para a cultivar "Nayarit" apenas a omissão de P reduziu a produtividade. Para essa cultivar o incremento de P e K aumentou a produtividade. A cultivar "Nayarit", mais produtiva que "Juliana", absorveu maiores quantidades de N, P e K. As eficiências de recuperação desses nutrientes por ambas cultivares de cenoura foram baixas.

ABSTRACT The objective of this work was to evaluate the carrot crop recovery efficiency of nitrogen, phosphorus and potassium from fertilizers. Two experiments were conducted in an experimental area in Rio Paranaiba - MG. The cultivar ("Juliana‟) was sown during the summer period and the cultivar "Nayarit‟ during the winter period. In both experiments, the treatments consisted of six fertilization combinations of N, P2O, K2O (kg ha-1): fertilization without N (0-500-450), without P (100-0-450), without K (100-500-0), standard (100-500-450), higher than standard (100-700-600) and lower than standard (100-300-300). The harvest was carried out when most of the roots presented commercial standard well accepted by the consumers. The fresh and dry matter of roots and leaves were quantified, and the yield was calculated based on the fresh matter. The analysis of N, P and K contents in leaves and roots were carried out by harvest time, and the nutrients absorption and exportation were determined based on these contents and on the dry matter of roots and leaves. N, P and K omissions reduced the yield of the cultivar "Juliana‟. For the cultivar "Nayarit‟, only P omission reduced and P and K fertilizations increased the yield. The cultivar "Nayarity‟, which is more productive than "Juliana", absorbed more quantities of N, P and K. Carrot recovery efficiency of nitrogen, phosphorus and potassium is low.

ABSTRACT Univariate methods for diagnosing nutritional status such as the sufficiency range and the critical level for garlic crops are very susceptible to the effects of dilution and accumulation of nutrients. Therefore, this study aimed to establish bivariate and multivariate norms for this crop using the Diagnosis and Recommendation Integrated System (DRIS) and Nutritional Composition Diagnosis (CND), respectively. The criteria used were nutritional status and the sufficiency range, and then the diagnoses were compared. The study was performed in the region of Alto Paranaíba, MG, Brazil, during the crop seasons 2012 and 2013. Samples comprised 99 commercial fields of garlic, cultivated with the cultivar “Ito” and mostly established in Latossolo Vermelho-Amarelo Distrófico (Oxisol). Copper and K were the nutrients with the highest number of fields diagnosed as limiting by lack (LF) and limiting by excess (LE), respectively. The DRIS method presented greater tendency to diagnose LF, while the CND tended towards LE. The sufficiency range of both methods presented narrow ranges in relation to those suggested by the literature. Moreover, all ranges produced by the CND method provided narrower ranges than the DRIS method. The CND method showed better performance than DRIS in distinguishing crop yield covered by different diagnoses. Turning to the criterion of evaluation, the study found that nutritional status gave a better performance than sufficiency range in terms of distinguishing diagnoses regarding yield.

ABSTRACT Leaf analysis may identify nutrient deficiency or excess in plant tissue. The aim of this study was to determine reference values and generate nutritional diagnosis from the results of leaf analysis of the carrot crop (Daucus carota L.) by the methods of Critical Level, Sufficiency Range, Diagnosis and Recommendation Integrated System, and Compositional Nutrient Diagnosis. Contents of N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn were determined in 210 carrot fields in the 2012 and 2013 crop seasons in the Alto Paranaíba region, MG, Brazil. The whole plant shoot was sampled at harvest time to generate reference values for diagnosis. The high yielding subpopulation showed yield higher than 87.8 Mg ha-1. The four diagnostic methods generated similar reference values of nutrients, but different from those found in the literature. Leaf diagnosis through nutrient content in the shoot at harvest time indicated Mn as the most limiting nutrient for growing carrot, followed by Mg, K, and Ca.

A razão entre nitrogênio (N) e potássio (K) pode ser importante para obtenção de cafés especiais, uma vez que doses adequadas destes nutrientes podem suprimir ou aumentar a concentração de certos compostos químicos essenciais ao sabor e aroma da bebida. Objetivou-se com este trabalho avaliar o efeito de diferentes relações N:K e doses de K na qualidade da bebida do café. Foram realizadas avaliações referentes à concentração de compostos químicos essenciais à formação de sabor e aroma dos grãos e teores de N, K e cafeína em folhas e grãos. A relação N:K e o K são importantes definidores da qualidade da bebida de café sendo a melhor qualidade observada na relação N:K 1:1.56. Os grãos que apresentam melhor qualidade da bebida têm maiores atividade da PPO, cafeína, índice de coloração, açúcares redutores e menores acidez total titulável, pH, condutividade elétrica e lixiviação de potássio.

The ratio of nitrogen (N) to potassium (K) is important in the production of specialty coffees because the relative amounts of N and K can either suppress the formation or increase the concentration of compounds that are essential to the flavor and aroma of specialty coffees. The purpose of this study was to evaluate the effect of different N:K ratios (w/w) and K doses on the cup quality of coffee. The concentrations of chemical compounds essentials to achieve good flavor and aroma, the N and K contents, and the caffeine contents of coffee leaves and beans were evaluated in this study. The N:K ratio and the K dose were found to be important factors in cup quality, the best quality corresponding to an N:K ratio of 1:1.56. The best cup quality was obtained from beans with greater PPO activity, caffeine, color index, and sugars and lower total tritatable acidity, pH, electrical conductivity and leached potassium.

Dentre os micronutrientes, o Zn é um dos mais importantes para o cafeeiro, especialmente em solos argilosos e ácidos do sudeste brasileiro, onde seu cultivo é uma importante atividade econômica. Este trabalho objetivou avaliar a eficiência de uso do zinco por variedades de cafeeiro cultivadas em doses contrastantes do elemento. Mudas de 11 variedades foram cultivadas, em casa de vegetação, em solução nutritiva, com duas concentrações de zinco (0,0 e 6,0 µmol L-1). Após oito meses determinaram-se: biomassa seca dos órgãos da planta, concentração de zinco, eficiências de absorção, de produção de biomassa, de produção de biomassa foliar e de utilização de zinco. A concentração de zinco fornecida afetou todas as características avaliadas. A produção de biomassa seca de folhas apicais foi a mais afetada, proporcionando grande variabilidade de resposta entre as variedades. A variedade IPR-103 foi a mais eficiente no uso de zinco, as variedades San Ramon e São Bernardo as menos eficientes. A 'Rubi' apresentou alta e baixa eficiência de utilização de zinco quando cultivada nas doses 0,0 e 6,0 µmol L-1. A variedade Oeiras apresentou baixa eficiência de utilização na dose de 6,0 µmol L-1. As demais variedades estudadas foram moderadamente eficientes no uso do elemento.

Among micronutrients, zinc (Zn) is important for coffee tree cultivation, especially in the clayey acid soils of Brazil's southeast region, where coffee production is an important activity. This study aimed to evaluate the Zn use efficiency of coffee tree varieties using two zinc concentrations. Seedlings of 11 varieties of coffee trees were grown in a greenhouse in nutrient solution containing either 0.0 or 6.0 µmol L-1 of Zn. After eight months, we evaluated the total biomass production, leaf biomass production, concentration of Zn in the plant organs, absorption efficiency, and Zn use efficiency. All characteristics were affected by the Zn concentration. The biomass production of apical leaves was most affected by the Zn treatments, with high variability for the studied varieties. The 'IPR-103' variety had the highest Zn use efficiency, and the 'San Ramon' and 'San Bernardo' varieties had the lowest Zn use efficiency. The 'Rubi' variety had a high and low Zn use efficiency when grown at 0.0 and 6.0 µmol L-1 of zinc, respectively. The 'Oeiras' variety had a low Zn use efficiency when cultivated at 6.0 µmol L-1 of zinc. The other varieties studied were moderately efficient in their use of zinc.

O suprimento adequado de nutrientes ao cafeeiro é essencial para obtenção de alta produtividade. O objetivo deste trabalho foi avaliar o efeito do nitrogênio, do potássio e da relação N:K no crescimento vegetativo e reprodutivo do cafeeiro. Para isto, plantas de café receberam solução nutritiva, contendo K nas concentrações de 1,08; 2,15; 3,23 e 5,38 mmol L-1, combinadas com a dose de 6 mmol L-1 de N, obtendo-se as relações N:K (p/p):1,0:0,5; 1,0:1,0; 1,0:1,5; 1,0:2,5. O tratamento controle continha as doses de 3 e 1,61 mmol L-1 de N e K, respectivamente, resultando na relação N:K (p/ p) de 1,0:1,5. Avaliaram-se a altura, o diâmetro do caule, número de nós do oitavo ramo plagiotrópico (ramo índice), o número de pares de ramos plagiotrópicos e o número de nós do ramo ortotrópico a cada três semanas após o início do experimento. Realizaram-se também análises da composição química dos grãos beneficiados e folhas, no período entre a floração e expansão rápida dos frutos, produção de café cereja por planta e classificação dos grãos quanto ao tamanho. O N influenciou principalmente as características de crescimento vegetativo e o K influenciou principalmente as características de crescimento reprodutivo, avaliadas pela produção. A menor produção resultou em percentagens mais elevadas de grãos retidos nas peneiras com crivos maiores que 16/64 polegadas, enquanto a maior produção promoveu aumento na percentagem de grãos retidos nas peneiras com crivos menores que 16/64 polegadas.

An adequate supply of nutrients is essential for obtaining high yields of coffee. The objective of this study was to evaluate the effect of N, K and the N:K ratio on vegetative and reproductive growth of coffee. For this purpose, coffee plants were grown in nutrient solution containing K in the concentrations of 1.08; 2.15; 3.23 and 5.38 mmol L-1 combined with a dose of 6 mmol L-1 N, resulting in the N:K ratios (w/w): 1:0.5; 1:1; 1:1.5 and 1:2.5. The control treatment consisted of the doses 3 and 1.61 mmol L-1 of N and K respectively, resulting in the N:K ratio (w/w) 1.0:1.5. The following variables were evaluated: height, stem diameter, number of nodes of the eighth plagiotrofic branch (index branch), pairs of plagiotrofic branches and number of nodes in the orthotropic branch every three weeks from the beginning of the experiment. Additionally, it was evaluated the chemical composition of processed beans and leaves between the flowering and the rapid expansion stage of the cherry beans, production of cherry beans per plant and classification of beans according to the size. N influenced mainly the characteristics of vegetative growth and K influenced mainly the reproductive growth evaluated by the production. The lowest production resulted in the highest percentages of beans retained on sieves with holes larger than 16/64", while the highest production promoted an increase in the percentage of beans retained on sieves with holes smaller than 16/64".