Elizandra Pivotto Pavanello

Respiratory quotient: innovative method for monitoring ‘Royal Gala’ apple storage in a dynamic controlled atmosphere

Apples (Malus domestica, Borkh.) which are not stored at low temperature or in a properly controlled atmosphere (CA) may have a high metabolic rate during the postharvest stage resulting in losses in quality. The aim of this study was to evaluate the quality of ‘Royal Gala’ apple fruit stored in accordance with a new method of dynamic controlled atmosphere (DCA).The respiratory quotient (RQ) was monitored at two temperatures which were then compared using a commercially available technology based on chlorophyll fluorescence DCA (DCA-CF) and static CA. Ethylene production and respiration rates were lower in apples stored in DCA than in CA, as a result of lower 1-aminocyclopropane-1-carboxylate oxidase activity, especially in apples stored in DCA-RQ2. Flesh firmness of apples stored in DCA did not differ from those stored in CA. Apples stored at 1 °C had less flesh breakdown occurrence and a high percentage of healthy fruit. ‘Royal Gala’ stored at DCA-RQ2 had less flesh breakdown than apples stored in CA; however, the apples stored in DCA-CF did not differ from those stored in DCA-RQ2 and CA. Apples stored at the highest RQ value (6 and 4), especially at 0.5 °C, had low O2 injury occurrence after storage. However the increase in temperature to 1.0 °C, reduced the occurrence of this disorder. Therefore, storage in DCA-RQ2 at 1 °C or DCA-CF at 0.5 °C are the recommendations of preference for ensuring maintenance of quality in ‘Royal Gala’ apples after eight months of storage.

Avaliação de genótipos de morangueiro quanto à qualidade e potencial de armazenamento

The objective of this study was to evaluate the quality of strawberry cultivars and clones, and their potential for storage under refrigeration. The experimental design was a randomized block design with four replicates of approximately 150 g each. The treatments consisted in the evaluation of three cultivars and four clones, namely: LBH 15.1 Araza, SGH 140.3 Guenoa, LBF 236.3 Yvapita, LBG 121.4, LBK 16.1, LBK 35.1 and LBK 28.1. Evaluations were made at harvest and after ten days of storage at -0.5oC, plus two days at 20oC. The parameters evaluated were firmness, acidity, soluble solids, TSS/ TTA ratio, ascorbic acid, presence of rotting and weight loss. In terms of quality, cv. Guenoa presented low acidity and high TSS e ascorbic acid, high TSS/TTA ratio and also showed better conservation, presenting low incidence of decay during storage. The cultivar LBF 236.3 Yvapita and the clone LBK 28.1 showed the lowest vitamin C content and TSS/TTA ratio, which compromises its quality. The quick reduction of firmness and increased susceptibility to decay presented by LBF236.3 Yvapita and LBK 28.1 show a low potential for conservation under refrigeration. Cultivars and clones that had higher quality at harvest, also showed better post-harvest conservation.

Produtividade e qualidade de figos Roxo de Valinhos submetidos à fertirrigação e ao armazenamento refrigerado

Effect of fertigation and cold storage on yield and quality of ‘Roxo de Valinhos’ figs The low productivity of figs in Brazil is usually associated with water and nutrition deficiency. The aim of this work was evaluate the effect of fertigation with doses of nitrogen and potassium on yield and quality of the ‘Roxo de Valinhos’ figs during cold storage. The field experiment was conducted during two years, and in the last year, the fruits were stored at 0.5° C for fifteen days. The treatments were a combination of doses of of nitrogen (150, 250, 350 and 450 kg ha -1 ) and potassium (150, 250 and 350 kg ha -1 ) applied by fertigation. The results showed that doses up to 250 kg ha 1 of N and K in fertigation increased the yield of ‘Roxo de Valinhos’ figs, and these doses increased the yield among the treatments. Fertigation increased yield of green figs by by 96.7% and ripe figs by 49% compared with the control. The rates of N and K and the application form did not affect the fruit quality during cold storage.

Manejo do etileno e sua relação com a maturação de maçãs 'Gala' armazenadas em atmosfera controlada

This research aimed to evaluate the quality of Gala apples submitted to different ways of ethylene handling, through inhibition of synthesis, inhibition of action and ethylene absorption in storage room, associated with two temperatures. The treatments originated from the combination between two temperatures (0.5 °C e -0.5 °C) and application of aminoethoxyvinylglycine (AVG), 1- methylcyclopropene (1-MCP) and ethylene absorption. All treatments were stored in controlled atmosphere with 1.2 kPa O2 + 2.5 kPa CO2. Ripening and quality evaluations were carried out after eight months of storage more seven days at 20 °C. Preharvest AVG application maintained fruit skin greener at the opening of storage rooms. After seven days at 20°C, the treatment with AVG resulted in greener skin, with lesser decay incidence, higher flesh firmness and less senescent breakdown incidence. The lower ethylene production of AVG-treated apples resulted in lower respiration and highest titratable acidity levels. The temperature of 0.5 °C maintained higher of the titratable acidity and reduced senescent breakdown incidence when compared with the temperature of -0.5 oC. The ethylene absorption and 1-MCP application were also efficient in the control of the senescent breakdown and loss of firmness, however less effective than AVG treatment.

Aplicação de 1-metilciclopropeno, estresse inicial com baixo oxigênio e armazenamento em ultrabaixo oxigênio na qualidade de maçã Fuji

The aim of this research was to evaluate the effect of 1-MCP application in combination with initial low oxygen stress and storage in controlled atmosphere with ultra-low oxygen on Fuji apple quality preservation. The evaluated treatments consisted of 1-MCP application (with or without 1000nL L-1) combined with five levels of the factor storage condition (without initial stress + 0.6kPa O2, 1 stress + 0.6kPa O2, 1 stress + 0.8kPa O2, 2 stresses + 0.6kPa O2 and without initial stress + 1.0kPa O2). Initial low oxygen stress was applied by 14 days at 0.2kPa O2. The fruits were stored in these conditions for eight months at -0.5±0.2°C and relative humidity of 96±1%, followed by seven days at 20±1°C. In all treatments, the CO2 was kept below 0.5kPa. The storage without initial low oxygen stress associated with 1.0kPa or 0.6kPa O2 maintained the pulp firmer and with the higher titratable acidity, moreover provided a lower incidence of decay after storage during eight months and shelf life at 20°C. The 1-MCP provided lower activity of ACC oxidase enzyme, however, did not reduces ethylene production and failed to delay the loss of firmness and the control decay. Initial stress of 14 days with 0.2kPa O2 reduced the conservation of Fuji apples.

Expectativas dos alunos de diferentes faixas etárias do Técnico em Agropecuária quanto à Educação Profissional

It is proposed from this investigative study to analyze the expectations of entering students of technical course in Agriculture, with different age groups, as the contribution of professional education for its professionalism and continued education. A mixed questionnaire was applied and, to evaluate the data, the group was divided into two categories. Differences in their school history were evidenced, as well as their expectations regarding the course. The younger students have a tendency to be conducting the course because they could not join a college. On the other hand, older students seek in technical knowledge to act professionally or to be a complement of their graduation. Thus, the teachers and the school need to strengthen the possibilities that the course provide, in order to stimulate the course ending, in order to form professionals to contribute to the community.