Phenolic compounds and carotenoids amounts on guava epicarp injury, 'girdling'

A anomalia do epicarpo da goiaba, comumente relatada por agricultores e técnicos como o "anelamento juvenil da goiaba", tem causado preocupação devido à desinformação sobre o assunto. O objetivo deste estudo foi analisar quimicamente as concentrações de substâncias fenólicas e carotenoides na região do epicarpo de goiabas afetadas pelo "anelamento", visando a caracterizar essa anomalia previamente relatada. Foram analisadas substâncias fenólicas (taninos, flavonas/flavonóis, antocianinas e fenóis totais) e carotenoides em epicarpos de frutos verdes e maduros de goiabeiras cv. Paluma, com e sem anomalia. O delineamento experimental adotado foi o inteiramente casualizado, sendo estabelecidos seis tratamentos com o epicarpo dos frutos maduro sem anomalia na região inferior (FMSI); frutos maduros sem injuria na região superior (FMSS); frutos verdes sem anomalia na região inferior (FVSI); frutos verdes sem anomalia na região superior (FVSS); frutos verdes com anomalia na região inferior (FVCI); frutos verdes com anomalia na região superior (FVCS). Dentre as substâncias analisadas, os carotenoides, os taninos e os fenóis totais mostram indicativos para a caracterização do anelamento. Tanto substâncias fenólicas quanto carotenoides apresentam propriedades antioxidantes e, dessa forma, poderiam estar relacionadas à defesa antioxidante causada por um fator de estresse ainda desconhecido, que promove o "anelamento" característico apresentado pelas goiabas.Guava epicarp injuries, popularly known as "girdling", have been concerned technicians and producers due to misunderstand about their causes. The objective of this study was to analyze the amounts of phenolic compounds and carotenoids present on guava epicarp region affected by injury ("girdling") in order to characterize chemically those regions. Concentrations of phenolic compounds (tannins, flavones/flavonols, anthocyanins and total phenolic compounds) and carotenoids were analyzed on tissue from unripe and ripe guava injured and non-injured epicarp fruits (Psidium guajava cv. Paluma). The experimental design was randomized, and were established six treatments: epicarp from ripe fruit without injury in the lower (FMSI) and upper region (FMSS) of the fruit, unriped fruit without injury (lower - FVSI - and upper region - FVSS), injured unriped fruit with injury (lower - FVCI - and upper region - FVCS). Higher concentrations of phenolic compounds, carotenoids of tannins, were found on tissues of unripe fruit epicarp with "girdling" when compared with health epicarps. Results showed the participation of phenolics compounds (tannins) and carotenoids as possible substances that characterized the injury formation. Although phenolic compounds and carotenoids have antioxidant properties and are often related as antioxidant defenses, the causes of "girdling" of guava fruits are still unknown

Calagem na nutrição de cálcio e no desenvolvimento do sistema radicular da goiabeira

The application of lime in acid soils improves the plant root system and, consequently, enhances water and nutrients absorption by the plants. The objective of this work was to evaluate the effects of lime application on the development of root system and calcium nutrition of guava plants cultivated in an acid distrofic Red Latosol (Typic Hapludox). Soil samples were collected in four equidistant points, at 75 cm of the trunk and at 0–20 cm and 20–40 cm of depth, in the plots that had received zero (control), 3.7 and 7.4 t ha-1 of lime. Soil samples were chemically analysed. Lime material was applied at planting, incorporated with grating and moldboard plow. On the second and third years after guava plantation, effects of liming in chemical properties were determined. Forty two months after lime incorporation in the soil (third year of guava plants cultivation), samples of roots were collected with a cylindrical auger, for dry mass and calcium content evaluation. Samples of leaves were also collected. Liming corrected soil acidity increased base saturation and improved calcium availability to plants and, consequently, improved guava root system. Calcium concentrations of 30 mmolc dm-3 in the soil and of 7.5 g kg-1 in the roots were associated with the highest guava root growth.A aplicação de calcário em solos ácidos promove maior desenvolvimento do sistema radicular das plantas e consequentemente, melhora a absorção de água e nutrientes. O objetivo deste trabalho foi avaliar os efeitos da aplicação de calcário no solo, no desenvolvimento do sistema radicular e na nutrição de cálcio de goiabeiras cultivadas em um Latossolo Vermelho distrófico ácido. Analisaram-se amostras de solo coletadas em quatro pontos eqüidistantes, a 75 cm do tronco, nas camadas de 0–20 e 20–40 cm de profundidade, de parcelas que receberam 0, 3,7 e 7,4 t ha-1 de calcário. O calcário foi aplicado em pré-plantio, incorporado com arado de aivecas e grade aradora, na camada de 0–30 cm de profundidade. Durante o segundo e o terceiro ano de cultivo da goiabeira, avaliaram-se os efeitos da calagem nas propriedades químicas do solo. Aos 42 meses após a incorporação do calcário (terceiro ano de cultivo da goiabeira), realizou-se a amostragem das raízes com trado cilíndrico serrilhado para a avaliação da matéria seca e do teor de cálcio radicular e e também realizou-se a amostragem de folhas. A calagem promoveu a correção da acidez do solo, aumentando a saturação por bases, com conseqüente incremento da disponibilidade e absorção de cálcio pela planta, proporcionando maior desenvolvimento do sistema radicular da goiabeira. Concentrações de cálcio próximas de 30 mmolc dm-3 no solo e teor desse nutriente de 7,5 g kg-1 nas raízes, estiveram associados ao maior crescimento radicular da goiabeira

Desenvolvimento inicial e estado nutricional do maracujazeiro em resposta à aplicação de lodo têxtil

In the treatment of liquid effluents of the textile industry the textile sludge results as residue. This work aimed at evaluating the effect of sludge application to the substrate of production of passion fruit cuttings in the development, and nutritional status of plants. Experimental design used was randomized blocks with five treatments and four replications. The textile sludge was applied in the doses of 10, 15, 20 and 30 g per pot (dry base), corresponding 10, 15, 20 and 30 t ha-1, respectively, and a control without application. Plants were fertilized with N, P, K, Zn and B at 300, 450, 150, 5, and 0.5 mg dm-3, respectively. The experimental unit was represented by pots with 2 dm3 of a Red Latosol (Oxisol) (V = 29%). After 100 days the textile sludge corrected soil acidity. However, in doses superior to 10 t ha-1 it caused plants death. The textile sludge increased the content of N, K, S, B, Mn and Zn, reduced Ca and Mg content, and it didn't alter Cu and Fe content of passion cuttings dry matter.O processo de tratamento de efluentes líquidos da indústria têxtil gera, como resíduo, um lodo de características orgânicas com concentração significativa de sódio e potássio. Objetivou-se quantificar os efeitos da aplicação do lodo ao solo, sobre o desenvolvimento inicial do maracujazeiro, e avaliou-se o crescimento e o estado nutricional das plantas. O delineamento experimental foi em blocos ao acaso, com quatro repetições de cinco tratamentos, que consistiram na aplicação de lodo têxtil, nas doses de 10, 15, 20 e 30 g vaso-1 (base seca), correspondentes a 10, 15, 20 e 30 t ha-1, respectivamente, além da testemunha sem aplicação do resíduo. As mudas receberam adubação básica com N, P, K, Zn e B, nas doses de 300, 450, 150, 5, e 0,5 mg dm-3, respectivamente. A unidade experimental foi constituída por vasos com 2 dm3 de amostra de um Latossolo Vermelho distrófico (V = 29%). Após 100 dias da semeadura, o lodo têxtil corrigiu a acidez do solo. Entretanto, em doses superiores a 10 t ha-1, promoveu a morte das plantas. O lodo têxtil aumentou os teores de N, K, S, B, Mn e Zn, diminuiu os de Ca e Mg e não alterou os de Cu e Fe da parte aérea das mudas

Compositional meta-analysis of citrus varieties in the state of São Paulo, Brazil

Brazil is the largest orange (Citrus sinensis) producer worldwide. The nutrient management of orange orchards is designed from experiments on a limited number of varieties. This knowledge is transferred to other varieties by diagnosing tissue nutrient composition. Nutrient diagnostic tools are based on nutrient concentration (critical minimum value or CMV) and ratio (Diagnosis and Recommendation Integrated System or DRIS) norms that disregard the compositional nature of analytical data and the limited number of nutrient ratios that can be diagnosed independently in a given composition. The diagnosis of cationic micronutrients is also biased by contamination from fungicides. Compositional data analysis that can avoid such problems has been first applied to tissue analysis of agricultural crops using centered log ratios (Compositional Nutrient Diagnosis – CND-clr). The isometric log ratio (ilr) transformation is a new approach based on binary nutrient ratios and the principle of orthogonality (CND-ilr). Binary partitions can be defined and varietal nutrient profiles classified based on positive and negative nutrient interactions and meta-analysis. We analyzed 11 nutrients (N, S, P, K, Ca, Mg, B, Cu, Zn, Mn, Fe) in tissue samples across 108 orchard areas, i.e. 31 ‘Valencia’, 22 ‘Hamlin’, 20 ‘Pêra’, and 35 ‘Natal’. Nutrients were partitioned between macro- and micro-nutrients as well as anionic and cationic species. The effect size of varieties over ‘Valencia’ was quantified by the mean and standard deviation of ilr values across ilr coordinates. Specific varietal nutrient profiles and ilr norms were defined. To guide correcting nutrient deficiencies by appropriate nutrient management, compositions can be varied by a perturbation vector on nutrients with to the largest and most negative influence on ilr differences from ilr norms until the Aitchison distance falls below critical value

Machine Learning, Compositional and Fractal Models to Diagnose Soil Quality and Plant Nutrition

Soils, nutrients and other factors support human food production. The loss of high-quality soils and readily minable nutrient sources pose a great challenge to present-day agriculture. A comprehensive scheme is required to make wise decisions on system’s sustainability and minimize the risk of crop failure. Soil quality provides useful indicators of its chemical, physical and biological status. Tools of precision agriculture and high-throughput technologies allow acquiring numerous soil and plant data at affordable costs in the perspective of customizing recommendations. Large and diversified datasets must be acquired uniformly among stakeholders to diagnose soil quality and plant nutrition at local scale, compare side-by-side defective and successful cases, implement trustful practices and reach high resource-use efficiency. Machine learning methods can combine numerous edaphic, managerial and climatic yield-impacting factors to conduct nutrient diagnosis and manage nutrients at local scale where factors interact. Compositional data analysis are tools to run numerical analyses on interacting components. Fractal models can describe aggregate stability tied to soil conservation practices and return site-specific indicators for decomposition rates of organic matter in relation to soil tillage and management. This chapter reports on machine learning, compositional and fractal models to support wise decisions on crop fertilization and soil conservation practices

Calcário e escória de siderurgia avaliados por análise foliar, acúmulo, e exportação de macronutrientes em cana-de-açúcar

A opção de uso de materiais corretivos alternativos como as escórias de siderurgia, pode influenciar na absorção de nutrientes pela planta e, consequentemente, na diagnose foliar, acúmulo e exportação de nutrientes. Com o objetivo de estudar o efeito da aplicação de doses de escória de siderurgia e de calcário na absorção de macronutrientes pela cana-de-açúcar (variedade SP80-1842), foi instalado em janeiro de 1998, em Ituverava-SP, um experimento de campo. Aplicou-se escória de siderurgia e calcário, em quatro doses equivalentes 0; 1,23; 2,52 e 3,80 t ha-1 de CaCO3, em um Latossolo Vermelho-Amarelo distrófico, em pré-plantio na cana-planta. Determinaram-se, além da produção de colmos, as concentrações de macronutrientes na folha +3 da cana-planta e da cana-soca (aos 120 dias após a emergência dos brotos) e na parte aérea da cana-soca (aos 345 dias após a emergência dos brotos). Os materiais corretivos e as doses não alteraram a absorção de macronutrientes pela cana-de-açúcar. Houve maior acúmulo e exportação de macronutrientes de acordo com as doses de ambos corretivos. A escória de siderurgia comportou-se de modo semelhante ao calcário na nutrição da cana-de-açúcar quanto aos macronutrientes.Slag can be used as an alternative for lime as soil amendment, having influence on nutrient uptake by the plant and, as a result, on leaf analysis and nutrient accumulation. To study the effect of the application of increasing rates of slag and lime stone on the uptake of macronutrients by sugar cane (variety SP 80-1842) an experiment was installed under field conditions, in January 1998, at Ituverava-SP, Brazil. Slag and limestone were applied to the sugarcane crop at planting, in four rates: 0; 1.23; 2.52 and 3.80 t ha-1 of CaCO3, using a Typic Haplorthox. In addition to the cane stalk production a verification was performed for the first and second ratoons (120 days and 345 after the emergence of the shoots, respectively). Macronutrient concentrations on the leaf +3 and in the aerial part of sugar cane for were analysed for the second cutting. Through leaf analysis data it was found that the corrective agents and rates did not modify the degree of absorption of macronutrients by the sugar cane. Slag had some effect on sugarcane evaluation, acting in a similar way in comparison to limestone, in relation to the nutrition of the plant

Anatomical modifications in the cell wall of guava as influenced by calcium

O objetivo deste trabalho foi avaliar modificações na parede celular de goiaba, em frutos de plantas submetidas à aplicação de cálcio (Ca). Frutos de goiabeira cultivar Paluma foram colhidos em área sem aplicação de calcário e com aplicação de corretivo. Os frutos que receberam aplicação de Ca tiveram as paredes celulares e as lamelas médias bem definidas e estruturadas; nos frutos sem aplicação de cálcio, as paredes celulares estavam desestruturadas e com desorganização da lamela média. A aplicação de Ca é efetiva na organização subcelular de frutos de goiabeira e aumenta sua vida de prateleira.The objective of this work was to evaluate modifications in cell walls of guava fruits produced either under liming or not. The study made use of fruits of the Paluma cultivar harvested from nonlimed and limed areas. Fruits harvested from the calcium treated plants had cell walls and the middle lamella well defined and soundly structured. Fruits from the nontreated plants showed poorly structured cell walls and middle lamella. The application of calcium has an important effect on the subcellular structural organization of guava fruit and on the increase of fruits shelf life

Light composite Higgs from an effective action for technicolor

We compute an effective action for a composite Higgs boson formed by new fermions belonging to a general technicolor non-Abelian gauge theory, using a quite general expression for the fermionic self-energy that depends on a certain parameter (alpha), that defines the technicolor theory from the extreme walking behavior up to the one with a standard operator product expansion behavior. We discuss the values of the trilinear and quadrilinear scalar couplings. Our calculation spans all the possible physical possibilities for mass and couplings of the composite system. In the case of extreme walking technicolor theories we verify that it is possible to have a composite Higgs boson with a mass as light as the present experimental limit, contrary to the usual expectation of a heavy mass for the composite Higgs boson. In this case we obtain an upper limit for the Higgs boson mass, M_H ~ 700GeV for SU(2)_TC, and the experimental data on the Higgs boson mass constrain SU(N)_TC technicolor gauge groups to be smaller than SU(10)_TC.Comment: 10 pages, 6 figures. Minor changes on the text, typos corrected and references added. Matches version to be published in PR

Compositional meta-analysis of the nutrient profile of potato cultivars

While several potato (Solanum tuberosum L.) cultivars of different maturity groups (e.g. early, mid-season, late) are being selected each year as a result of successful breeding for disease resistance and market requirements, their nutrient management is based on past experience and few experiments. Nutrient profiles from leaf analysis can guide fertilization and liming programs of potato cultivars. Since leaf analytical data are strictly positive and compositional, nutrient profiling using raw data is spoiled by non normal distribution, resonance and spurious correlations. Compositional data analysis provides log ratio transformations that avoid such problems. Our objective was to derive nutrient profiles from tissue analysis using isometric log ratio (ilr) coordinates and meta-analysis for classification of cultivars into uniform nutrient management groups. The dataset comprised 678 potato fields producing more than 28.5 Mg marketable tuber ha-1, i.e. above Quebec average, of the early-, mid-, and late-season cultivars. The first mature leaf from top was sampled at the beginning of flowering for N, P, K, Ca, and Mg analysis. Anionic (N, P) and cationic (K, Ca, Mg) nutrients were arranged into binary partitions representing positive and negative nutrient interactions. Groups of cultivars were compared to ‘Superior’ using ilr mean and standard deviation in the mixed model of meta-analysis. We minimized the within-group heterogeneity (I2 value) by allocating cultivars iteratively between ilr groups. We derived group-specific ilr norms to compute the Aitchison distance. The critical value for nutrient imbalance was 0.38. To guide correcting nutrient deficiencies with appropriate nutrient management techniques, nutrient composition can be altered numerically by a perturbation vector on nutrients that lead to the largest and most negative ilr differences from ilr norms until the Aitchison distance falls below critical value