Edna Maria Mendes Aroucha

Características qualitativas de genótipos de cebola

Objetivou-se, com o trabalho, avaliar alguns atributos de qualidade de diferentes genotipos de cebola (Allium cepa L.), cultivados em Mossoro-RN. O experimento foi realizado na horta experimental no Departamento de Ciencias Vegetais da Universidade Federal Rural do Semi-Arido, em delineamento de blocos casualizados completos e quatro repeticoes. Os tratamentos foram constituidos pelos genotipos de cebola CNPH 6415, CNPH 6047, CNPH 6244, CNPH 6400 Chata, CNPH 6400 Redonda, CPACT 1, CPACT 2, CPACT 3, Granex 429, Belem IPA 9, BRS Cascata, Crioula Alto Vale, Bola Precoce, Primavera, Regia, Valeouro IPA-11, Brisa e Alfa Sao Francisco. As caracteristicas avaliadas foram teor de solidos soluveis totais, acidez total titulavel, teor de vitamina C e teor de acido piruvico (pungencia). Foram observadas diferencas significativas entre os genotipos para todas as caracteristicas avaliadas. Os genotipos apresentaram uma variacao significativa para todas as caracteristicas avaliadas, confirmando dessa forma que o fator genetico e determinante na caracterizacao de cada material. O teor de solidos soluveis totais variou de 6,67 a 11,63 (o Brix), vitamina C de 22,7 a 46,81 (mg acido ascorbico/100 ml de suco) e a acidez total titulavel de 0,19 a 0,45 (% de acido piruvico). Os genotipos apresentaram pungencia intermediaria com variacao de 5,0 a 12,73 (µmol/g), sendo os menos pungentes Granex 429, CNPH 6047, Regia, Primavera e Belem IPA 9.

Comparação de métodos de mensuração de área foliar para a cultura da melancia

The leaf area determination is very important in agronomic and physiologic studies, for supplying information on vegetal metabolism, and the techniques used should be simple, fast and accurate. This study aimed to compare different methods for measuring leaf area in the watermelon crop. For that, the accuracy of four measuring methods was evaluated (experiment 1) and leaf area was compared by using the integration method provided by the LI-COR ® model LI 3100 equipment, at 0, 30, 60, 90, and 120 minutes, after being determined with the aid of a scanner (experiment 2). For the experiment 1, a completely randomized design, with four treatments and 19 replications, was used. The treatments were equivalent to the Leaf area integrator AM 300, Leaf area integrator LI-COR ® model LI 3100, Leaf discs, and Digital image analysis (scanner) methods, and were compared to the reference method (scanner), in accordance with the linear correlation coefficient (r). For the experiment 2, a randomized blocks design, with six treatments and ten replications (leaves), was used, with each leaf being considered a block and their average compared by using the Tukey test at 5%. Differences were observed for leaf area estimation according to the method employed. The leaf discs method was considered the most accurate one, for the watermelon crop, and the LI-COR ® model 3100 is not recommended for this crop, particularly when readings are made at longer intervals.

Conservação pós-colheita de berinjela com revestimentos de fécula de mandioca ou filme de PVC

The postharvest conservation of eggplant fruits covered with cassava starch at 3% or covered with PVC film was compared. Fruits of the cultivar Embu were taken 147 days after sowing date in the field, in Mossoro, Rio Grande do Norte State, Brazil. Afterwards, the fruits were taken to the Postharvest Laboratory and stored during 15 days in environmental conditions (26-29oC and 50-75% RH). A 3 x 6 factorial scheme with three replications of three fruits per plot in a completely randomized design was used. The treatments consisted of the combination of three coating types (control, cassava starch and polyethylene film) with six storage times (0; 3; 6; 9; 12 or 15 days). The external appearance (1-5 scale), mass loss (%), flesh firmness (N) and soluble solids (oBrix), titratable acidity (% of citric acid), and ascorbic acid (mg/100 g of pulp) content of fruits were evaluated. Polyethylene film was the most efficient coat to keep the external appearance and to reduce the mass loss of the eggplant fruits. The cassava starch coat was not so efficient in extending the shelf life of eggplant fruits as the PVC film was. Based on external appearance, the conservation period for eggplant fruits was of 15 and 12 days for PVC film and cassava starch, compared to 9 days of the control treatment.

Qualidade de cenouras em diferentes densidades populacionais

Foi objetivo avaliar os efeitos de diferentes espacamentos de plantio sobre a qualidade de raizes de tres cultivares de cenoura nas condicoes de Mossoro, Rio Grande do Norte. O delineamento experimental utilizado foi em blocos casualizados, em esquema fatorial 6 x 3, com tres repeticoes, sendo o primeiro fator constituido pelos espacamentos: 20 x 4, 20 x 6, 20 x 8, 15 x 4, 15 x 6 e 15 x 8 cm e o segundo, pelos cultivares: Brasilia, Alvorada e Esplanada. As caracteristicas avaliadas nas raizes de cenoura foram: comprimento da raiz, diâmetro da raiz, comprimento do xilema, diâmetro do xilema, solidos soluveis (SS), acucares totais, acidez total (AT), vitamina C, relacao SS/AT e pH. Nao houve interacao significativa entre cultivares e espacamentos de plantio em qualquer das caracteristicas avaliadas. Os espacamentos influenciaram o comprimento e diâmetro da raiz e o comprimento e diâmetro do xilema. O cultivar Alvorada sobressaiuse nos solidos soluveis, acucares soluveis totais e relacao SS/AT.

Postharvest quality of different yellow melon hybrids stored under refrigeration

The objective of this work was to evaluate the shelf life of five yellow melon hybrids (AF7100, AF-1498, AF-5107, AF-4945 e AF-1805) grown in the Agropole Mossoro-Assu, RN. Fruits were harvested at commercial maturity and transported to the Postharvest Laboratory of the Universidade Federal Rural do Semi-Arido (UFERSA). Upon arrival, twelve fruits were randomly selected of each hybrid for characterization at zero time of storage. Right after, the other fruits were weighed, identified and stored in cold room at 10±1oC and 90±2% RH for 7, 14, 21, 28, 35, 42, 49, 56, 63 and 70 days. For all these storage times, it was performed evaluations for loss of mass, pulp firmness, external and internal appearances, pH, titratable acidity, soluble solids content, reducing sugars, and total soluble sugars. The experimental design was completely randomized in subdivided parcels according to the time. The parcel has the cultivar and the subparcel has the storage periods. It was used three replications, and the parcel was constituted by three fruits. There was a significant interaction between cultivars and storage time on the pulp firmness of the fruits. It was observed significant effects of the main factors on the other assessed traits. Higher fruit pulp firmness was observed in the hybrid AF-7100, followed by the hybrid AF-5107. There was an increment in the percentage of mass loss during the storage. It was not observed any damage on the external and internal appearances until 42 and 28 days of storage, respectively.

Incorporation of bentonite clay in cassava starch films for the reduction of water vapor permeability

Complete factorial planning 23 was applied to identify the influence of the cassava starch(A), glycerol(B) and modified clay(C) content on the water vapor permeability(WVP) of the cassava starch films with the addition of bentonite clay as a filler, its surface was modified by ion exchange from cetyltrimethyl ammonium bromide. The films were characterized by X-ray diffraction(XRD), fourier transform by infrared radiation(FTIR), atomic force microscopy(AFM) and scanning electron microscopy(SEM). The factorial analysis suggested a mathematical model thats predicting the optimal condition of the minimization of WVP. The influence of each individual factor and interaction in the WVP was investigated by Pareto graph, response surface and the optimization was established by the desirability function. The sequence of the degree of statistical significance of the investigated effects on the WVP observed in the Pareto graph was C>B>A>BC>AC. Interactions AB, BC and AC showed that the modified clay was the factor of greater significance.

Quality of 'Formosa' papaya produced at RN and storage under passive atmosphere.

Resumo - Este trabalho teve por objetivo avaliar o efeito da cera de carnauba (Primax Wax) e filme plastico de polietileno de baixa densidade “X-tend” sobre a vida util pos-colheita de mamao ‘Formosa’ (Tainung 1) produzido em Barauna – RN. O experimento foi conduzido no laboratorio de Pos-colhe ita da Universidade Federal Rural do Semi-Arido (UFERSA). Utilizou-se um esquema fatorial 3 x 6 com 3 repeticoes de tres frutos por parcela, constituindo na combinacao de 3 tipos de atmosferas (cera, filme de polietileno e controle) com 6 tempos de armazenamento (0; 7; 14; 21; 28; 35). Os frutos dos distintos tratamentos foram armazenados em câmaras frias a 10 ± 2 °C e UR 90 ± 5%, analisados em intervalos de sete dias. As caracteristicas avaliadas foram: aparencia externa, perda de massa, firmeza da polpa, solidos soluveis, acidez titulavel e vitamina C. Constatou-se ser o filme plastico o mais eficiente em manter a qualidade externa e reduzir a perda de massa dos frutos. A cera de carnauba, na concentracao utilizada, mostrou eficiencia relativa na conservacao de mamao quando comparada ao filme plastico. A vida util pos-colheita dos frutos mantidos sob atmosfera modificada foi de 35 dias e do controle apenas 28 dias. Palavras-chave - Carica papaya L. Alimentos-armazenamento. Fruta-conservacao.

Caracterização física e química de melão durante o seu desenvolvimento

ABSTRACT – The objective of this work was to study some physical and chemical changes during melon fruits development of fourcultivars. An experiment was carried out at the experimental area of Plant Science Department of Universidade Federal Rural do Semi-Arido - UFERSA, where the anthesis period was monitored. The experimental design used was of randomized complete blocks withthree replications in a split-plot scheme. To the plots were assigned the melon cultivars (‘AF 1749’, Hy-Mark, Rochedo e Caipir a) andto the subplots were assigned the harvested fruit times (7, 14, 21, 28, 35 and 42 days after anthesis). Four fruits per subplot of eachcultivar were harvested in the different fruit times, and then, they were analyzed for average weight, firmness, soluble solids, totalacidity, vitamin C and pH. There was a significant interaction between harvested fruit times and cultivars for average fruit we ight, pulpfirmness, total acidity, pH, vitamin C and soluble solids. The average fruit weight, pulp firmness, soluble solids, pH and Vitamin Cincreased and the total acidity decreased with the melon fruit’s development.Index Terms: Cucumis melo L., fruit quality, harvested fruit times, anthesis.

Postharvest shelf-life of bilimbi fruits (Averrhoa bilimbi L.) under cold storage

Aiming to evaluate the postharvest shelf-life of bilimbi fruits (Averrhoa bilimbi l.) stored under cold storage, bilimbi fruits were harvested in two maturation stages (determined by the peel color) at ten plants in Arez -RN, Brazil, in November 2006 and transported in polystyrene box containing ice´s bag to the Universidade Federal Rural do Semi-arido, Mossoro - RN. The fruits were placed in polystyrene trays, packed with PVC film and maintained at 10 ± 1 oC and 95% RH. It was used a completely randomized design in 2 x 6 factorial scheme, which consisted of stadiums (green or yellow) and the period of 0, 3, 5, 7, 9, 11 days, respectively. It was evaluated external appearance, soluble solids, flesh firmness, weight loss, pH, titratable acidity (TA), ascorbic acid and ratio. There was an increase of the weight loss, pH and the ratio and reduction of the content of ascorbic acid, TA and flesh firmness. The postharvest shelf-life of bilimbi fruits was 9 days.

Hydrophilicity, Solubility and Optical Properties in Composite Films of Gelatin and Bentonite Clay in its Natural Form or Modified

Bentonite clay was initially treated with a quaternary ammonium salt to increase its hydrophobicity, and then was dispersed in a gelatin matrix to serve as barrier to water vapor. The clays were characterized by IR spectroscopy in the infrared (FTIR), and X-ray diffraction (XRD), before and after ion exchange. The ion exchange held in the clay provokes on gelatin film a reduction of 65% in the water vapor permeability (WVP); a decrease in solubility of 55%; an increase of 35º in drop contact angle of water on the surface of the film; and 30% of raise in opacity.