Maturation of 'Baigent' apples protected by anti-hail nets and sprayed with aminoethoxyvinylglycine and ethephon

Abstract

The objective of this work was to evaluate the effect of pre-harvest spraying with aminoethoxyvinylglycine (AVG) and ethephon on fruit maturation of 'Baigent' apple (Malus domestica) trees grown under black anti-hail nets. The treatments were: control; 125 mg L-1 AVG, sprayed 30 days before anticipated harvest time (DBAH); 120 mg L-1 ethephon 7 DBAH; 62.5 mg L-1 + 62.5 mg L-1 AVG 30 and 20 DBAH; and 62.5 mg L-1 + 62.5 mg L-1 AVG 30 and 20 DBAH + 120 mg L-1 ethephon 7 DBAH. Fruit were harvested in the commercial harvest of the control treatment (harvest 1) and 14 days later (harvest 2). Yellowing and loss of firmness were delayed by the treatments with AVG and accelerated by that with ethephon. AVG application in a single rate of 125 mg L-1 30 DBAH or in two split rates of 62.5 mg L-1 30 and 20 DBAH delays fruit maturation. The pre-harvest application of AVG in a single rate reduces the red color of the fruits, which is not affected by application in split rates, combined or not with ethephon, regardless of the date of harvest.

Preharvest Applications of Aminoethoxivinylglycine in Mangifera indica L. “Ataulfo” Variety in Two Contrasting Environments

“…The action of AVG as an ethylene inhibitor could delay the cascade of events that lead to the enzymes biosynthesis related to cell wall degradation, such as polygalacturonase and pectinmethylesterase [26], with the consequent decrease in loss of weight [16]. This same effect has been recorded in other crops treated with AVG, such as M. domestica "Baigent" apple, which presented a greater breaking force of the epidermis of 12.3 N compared to 11.6 N of the control when 125 mg L −1 of AVG were applied, in Rio Grande do Sul, Brazil [27].…”

“…The effects that the AVG can induce are changes in the concentration of AT depending on the concentration, the applied period, and the variety of the fruit [25]. However, this effect may not always occur in the second year of AVG application, as in the case of the "Baigent" apple [27]. This • Brix/AT ratio constitutes the balance between acids and sugars, influenced by the balance between the flavor and aroma of the fruits [36].…”

Enhancing Anna Apples’ Productivity, Physico-Chemical Properties, and Marketability Using Sprays of Naphthalene Acetic Acid and Inhibitors of Ethylene for Alleviating Abiotic Stresses

“…All of the measured chemical attributes of Anna apples were significantly positively affected by the growth regulator treatments in the 2020 and 2021 seasons. The higher TSS content in apples sprayed with AVG or 1-MCP was related to the reduction in flesh firmness caused by the hydrolysis of cell walls and high content of soluble pectins, since those fruits had the lowest pulp firmness and a lower pulp penetration and skin rupture strength [80]. In other studies, starch degradation was increased by an NAA treatment but decreased by 1-MCP and AVG applications, which were similarly shown to delay fruit maturation [25,47,81].…”

Recent Development in the Preharvest 1-MCP Application to Improve Postharvest Fruit Quality

“…A common preharvest treatment for apples is to apply ethephon to accelerate maturity to bring forward the harvest period and to improve color development [31,32]. However, ethephon application leads to the activation of ethylene autocatalysis in fruit tissues, which is reflected as a drastically shortened harvest period and reduced storability.…”