Effect of Ethylene Inhibitors on Regulation of Ripening and Quality of “Fuerte” Avocado Fruits

Abstract

E THYLENE plays a major role in promoting fruit ripening and change in its biosynthesis could be an important avenue delay this process. During the 2019 and 2020 seasons, a number of ethylene-inhibiting chemicals were tested to regulate the ethylene production of Fuerte avocados and assess their quality. As well as studying the physical, chemical, physiological properties of the fruit and the properties of the oil. Fuerte avocadoes were surpassed with applications of AVG (Aminoethoxyvinylglycine) at 200ppm and Ag NO 3 at 100 µM, with slight differences between them, followed by CaCl 2 at 2.0%. Spraying these treatments on trees twice after 30 and 75 days from fruit set synergistically improved all tested characters as reduced fruit drop, increased yield, fruit quality and delayed ripeness over the other treatments or the control. Overall, both ethylene inhibitors were effective in reducing fruit softening and color development. On the other hand, all applied treatments that impeded the ethylene production or action delayed fruit maturation and this delayed fruit maturation paralleled with a reduction in TSS and acidity. Ethylene inhibitors treatments especially AgNO 3 at 100 μM, increased Fuerte avocadoes mineral contents of P, K, Mg and Ca along with preserve them from loss, dry matter% and fruit oil%, while slightly affected on iodine and peroxide values. With regard to fruit physiological properties the treatment of AgNO 3 at 100 μM and AVG at 200 ppm greatly reduced ethylene production, respiration rate, polyphenol oxidase (PPO) and pectin methylesterase activity (PME) enzymes activates.