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1.
Biosci. j. (Online) ; 38: e38094, Jan.-Dec. 2022. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-1415846

RESUMO

Intercropped systems with Conilon coffee might provide a better environment for coffee production. The aim of this study was to assess the microclimate and development of Conilon coffee intercropped with papaya trees. Papaya was planted with spacing of 3.20 x 2.40 m. The coffee trees were planted after eight months, with spacing of 3.20 x 1.60 m, in-between papaya trees (in the same row). The measurements were taken 0, 40 and 80 cm away from the coffee plants, both in the north and south direction. Concomitantly, an adjoining full sunlight coffee system (not intercropped) was also assessed. The measurements included atmospheric parameters (temperature, irradiance, and relative humidity) and vegetative parameters for the coffee plants (leaf area, relative chlorophyll index, length of plagiotropic branches, length of orthotopic branches and number of nodes) in three periods of the year. The intercropped system of Conilon coffee and papaya trees led to a decrease in both irradiance and temperature, and higher means of relative humidity during daytime in all the periods assessed, which contributes to a better environment for coffee cultivation. The shadow provided by papaya trees in the coffee plants contributed to a higher leaf area but did not affect neither the growth of both plagiotropic and orthotopic branches, nor the number of nodes and the etiolation. The intercropped system of Conilon coffee and papaya trees may be potentially used as a farming system to mitigate climate change.


Assuntos
Mudança Climática , Carica , Coffea/crescimento & desenvolvimento , Agricultura Sustentável
2.
Ciênc. rural ; 45(11): 1972-1979, Nov. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-762937

RESUMO

The aim of this study was to evaluate bioactive compounds in five apple cultivars and to analyze correlation of their quality characteristics with concentration of bioactive compounds. Phenolic compounds measurements were made in a spectrophotometer compared to a standard curve of gallic acid and expressed as gallic acid equivalent (GAE) per 100g of dry weight. Sugar and organics acids in five cultivars were quantified using high-performance liquid chromatograph (HPLC). Antioxidant activities were evaluated using three complementary tests 2,2-diphenyl-1-picrylhidrazyl (DPPH) scavenging activity, ferric reducing antioxidant power (FRAP), and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS). 'GoldRush' had the highest total phenolic compared to the other four cultivars. Additionally, 'GoldRush' had slightly higher, DPPH activity followed by 'Crimson Crisp' and 'Wine Crisp'. 'GoldRush' and 'Crimson Crisp' cultivars also have higher antioxidant capacity based on the ABTS and FRAP methods. The antioxidant capacity was significantly correlated with total polyphenols present in the different cultivars, while organic acids and fruit color showed slightly significant correlation to total phenols.


O objetivo do estudo foi de analisar compostos bioativos e correlacioná-los com características de qualidade em cinco cultivares de maçãs. Os compostos fenólicos foram mensurados com espectrofotômetro, comparando-se a curva padrão de ácido gálico e expressos em acido gálico equivalente por 100g de matéria seca. Os açúcares e ácidos orgânicos foram quantificados por meio de HPLC. A capacidade antioxidante foi mesurada por meio de três métodos: 2,2-diphenyl-1-picrylhidrazyl (DPPH), poder antioxidante de redução do íon ferro (FRAP) e 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS). A cultivar GoldRush foi a que apresentou maiores valores de polifenóis totais, quando comparada com as demais cultivares, e também maior capacidade antioxidante pelo método DPPH, seguida pela cultivar 'Crimson Crisp' and 'Wine Crisp'. 'GoldRush' and 'Crimson Crisp' foram os que apresentaram os maiores valores da capacidade antioxidante por meio dos métodos ABTS e FRAP. A capacidade antioxidante apresentou correlação significativa com polifenóis totais, já os ácidos orgânicos e cor da epiderme apresentaram correlação com os polifenóis totais.

3.
Ciênc. rural ; 44(10): 1725-1731, 10/2014. graf
Artigo em Português | LILACS | ID: lil-726286

RESUMO

Objetivou-se estudar a dinâmica dos carboidratos e a fluorescência da clorofila a em folhas de limeiras ácidas 'Tahiti', submetidas a épocas diferentes de anelamento e incisão anelar de ramos. Foram estudadas quatro épocas de realização de anelamento e incisão anelar, com um tratamento adicional, sem interrupção do floema. O anelamento, independentemente da época de realização, aumentou os teores de amido (55 a 90%) e açúcares solúveis totais (8 a 18%) nas folhas do 'Tahiti' até por volta dos 50 aos 60 dias. A incisão anelar, independentemente da época de realização, aumentou a concentração de amido (10 a 35%) em relação à testemunha, porém, o aumento foi inferior ao que ocorreu nas plantas aneladas (55 a 90%). O anelamento promoveu aumentos de F0 e redução da relação Fv/Fm, sendo os valores máximos (350) e mínimos (0,78), respectivamente, atingidos por volta dos 60 dias. Para as plantas da testemunha e incindidas, houve aumento de F0, sendo o valor máximo atingido aos 50 dias (320), porém inferior aos observados para o anelamento, e não houve alteração da relação Fv/Fm .


The aimed to study the dynamics of carbohydrates and chlorophyll fluorescence a in leaves of acid lime trees 'Tahiti' subjected to different times girdling and ringing of branches. It was studied four times the realization of girdling and ringing, with an additional treatment, without phloem interruption. The girdling, regardless of the time of realization, increased starch (55 to 90%) and soluble sugars levels (8 to 18%) in 'Tahiti' leaves until around 50 to 60 days. The ringing, regardless of achievement time, increased starch content (10 to 35%) to the control compared, but increase was less than to that which occurred in girdled plants (55 to 90%). The girdling promoted F0 increase and Fv/Fm ratio reduced, being the maximum (350) and minimum (0.78), respectively, were reached at about 60 days. For control and ringing plants, there was F0 increase, being the maximum value was achieved in 50 days (320), but lower than those observed for girdling, and there was no change in Fv/Fm ratio.

4.
Biosci. j. (Online) ; 26(6): 835-842, Nov.- Dec. 2010.
Artigo em Português | LILACS | ID: biblio-911549

RESUMO

O objetivo deste trabalho foi investigar a eficiência do método estatístico da cokrigagem na estimativa do Ca e Mg foliares da bananeira 'Prata Anã', utilizando os teores de Ca e Mg do solo como variáveis auxiliares. Foram coletadas em torno de cada planta quatro amostras de solo na camada de 0 ­ 0,2 m e em seguida homogeneizadas formando uma amostra composta. Para análise foliar foram coletadas de 10 a 25 cm da parte interna mediana do limbo foliar, na terceira folha a contar do ápice eliminando-se a nervura central, no período de inflorescência da planta, em uma malha regular, totalizando 100 pontos amostrais espaçados de 6 x 4 m. Obteve-se as margens de erros associadas à cokrigagem por comparação dos valores estimados com aqueles determinados em laboratório. Os resultados mostraram que a técnica foi capaz de estimar os nutrientes foliares com eficiência.


The objective of this study was to investigate the efficiency of the cokrigagem statistical method to estimate the Ca and Mg leaf of tree banana 'Prata Anã', using the Ca and Mg in the soil as auxiliary variables. Were collected around each plant four samples of soil layer from 0 - 0.2 m then homogenised to form a composite sample. For leaf analysis were collected from 10 to 25 cm from the inner leaf of the median, the third leaf from apex eliminating the midrib, from inflorescence of the plant in a regular grid, totaling 100 sampling points spaced 6 x 4 m. Obtained the margins of error associated with cokrigagem by comparing the estimated values with those determined in the laboratory. The results showed that the technique was able to estimate the nutrient content efficiently


Assuntos
Alimentos , Musa , Melhoramento Vegetal/estatística & dados numéricos , Características do Solo , Análise Espacial
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