Josuel Alfredo Vilela Pinto

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.

Qualidade de pêssegos cv. "Eldorado" tratados com aminoetoxivinilglicina e ethephon e armazenados em atmosfera controlada

The effect of preharvest application of aminoethoxyvinylglycine (AVG) and ethephon combined with controlled atmosphere (CA) storage conditions on peach fruit (cv. Eldorado) quality maintenance and chilling injury prevention was investigated, aiming at the maritime transport. Treatments evaluated were preharvest application of AVG (125g ha-1 and 250g ha-1 at 15 or 21 days before harvest), ethephon (140g ha-1 7 days before harvest), and control, combined with two CA conditions (1.0kPa O2 + 3.0kPa CO2 and 2.0kPa O2 + 5.0kPa CO2 at 0°C). After 24 days of CA storage plus 2 and 4 days of shelf-life at 15°C, preharvest application of ethephon stimulated fruit ripening by increasing ethylene production and decreasing both flesh firmness and titratable acidity. Application of AVG did not delay fruit ripening. However, fruit treated with 125g ha-1 of AVG at 15 days before harvest showed lower incidence of internal browning than ethephon-treated and control fruit. Furthermore, storage of fruit under CA with 2.0kPa O2 + 5.0kPa CO2 allowed higher titratable acidity and lower incidence of internal browning.