Impact of Reflective Ground Film on Fruit Quality, Condition, and Post-Harvest of Sweet Cherry (Prunus avium L.) cv. Regina Cultivated Under Plastic Cover in Southern Chile

Plastic covers protect fruits from cracking caused by pre-harvest rains in sweet cherry orchards; however, they can decrease the quality parameters of cherries, such as firmness, titratable acidity, color, and sugar content. This study evaluated the impact of a reflective ground film used for 21 or 34 DBH (days before harvest) in a commercial sweet cherry orchard (cv. Regina) grown under plastic cover in southern Chile. Our study showed that the exposition of cherry trees to the reflective film increased firmness and total soluble solid (TSS) content in fruits at harvest, homogenizing the concentration of sugars in fruits along the tree canopy. Additionally, using reflective film for 21 DBH increased the proportion of fruits greater than 32 mm in the upper canopy and the quantity of mahogany-colored cherries in the lower canopy, compared to trees un-exposed to the reflective film. Concerning fruit condition defects, the results reveal that using the reflective film increased the incidence of cracking in fruits in both the upper and lower zones of the canopy. Furthermore, we found that the incidence of orange skin and pitting in fruits decreased at post-harvest in trees exposed to the reflective film, but depending on the canopy zones. Moreover, fruits of trees exposed to the film for 34 DBH exhibited a higher incidence of browning pedicel post-harvest. Finally, according to our results, the antioxidant activity increased in fruits exposed to the reflective film for 21 DBH. Therefore, we can conclude that using reflective films on sweet cherry orchards can improve and homogenize the maturity parameters and the antioxidant activity of fruits; however, this practice can negatively impact the condition of fruits post-harvest.