Dinâmica da maturação e conservação pós-colheita de maçãs cultivadas em pomares sob telas fotosseletivas antigranizo

Abstract

Maturation dynamics and postharvest conservation of apples cultivated in orchards under photo-selective anti-hail netsPhoto-selective anti-hail nets have become popular for adding chromatic particles to the nets, changing the quality of the transmitted radiation and improving the physiological characteristics of plants and fruits. The objective of this study was to evaluate, in three parts, the effects of using differents photo-selective anti-hail nets on the quality of maturation in the field and on the postharvest conservation of apple fruits. 'Fuji Suprema' and 'Galaxy' apples were grown in commercial orchards using anti-hail nets: yellow, black, pearl, blue, red, mixed (white with black) and full sun (control). The first study aimed to evaluate the structural quality of the cuticle and epidermis and the metabolic quality of 'Fuji Suprema' and 'Galaxy' apples at harvest. The pearl and red nets showed promise. The pearl net influenced less ripe fruits, but with a certain presence of skin greasiness, which can be aggravated during storage. The red net provided more ripe fruits, better coverage and cuticle thickness. The second study investigated pre and postharvest storage quality of 'Galaxy' apples at 0 ± 1 °C 90 ± 5% RH in common atmosphere. The pearl and red nets and the full sun area presented fruits that reached commercial maturity before the other treatments. The red net and the full sun area influenced more ripe fruits, with less storage potential, while the apples under pearl net showed commercial quality, but were less ripe, which led to good postharvest potential. Finally, the third study sought to evaluate 'Fuji Suprema' apples during storage at 0 ± 1 °C 90 ± 5% RH in normal atmosphere. Although the nets did not present significant differences, it was observed that the full sun area favored fruits with better commercialization at the end of storage, as well as better stability. The mixed net presented fruits with a behavior closer to that of full sun area and can be used as an alternative in 'Fuji Suprema' cultivation areas that need protection against hail. This study showed that apples have different responses to the colors of photoselective anti-hail nets. It also provided good indications that photo-selective nets can be advantageous for growing apples in areas where there is a need for hail protection.