Preharvest Spray Hexanal Formulation Enhances Postharvest Quality in ‘Honeycrisp’ Apples by Regulating Phospholipase D and Calcium Sensor Proteins Genes

‘Honeycrisp’ (<i>Malus domestica</i> Borkh.), a premium applecultivar, is highly susceptible to bitter pit and decline in quality during long-term storage. In order to enhance the quality, an aqueous composition containing hexanal was applied as a preharvest spray. The effects of hexanal...

Description complète

Enregistré dans:
Détails bibliographiques
Auteurs principaux: Karthika Sriskantharajah, Walid El Kayal, Murali Mohan Ayyanath, Praveen K. Saxena, Alan J. Sullivan, Gopinadhan Paliyath, Jayasankar Subramanian
Format: article
Langue:EN
Publié: MDPI AG 2021
Sujets:
Accès en ligne:https://doaj.org/article/89b6672991644348926b0687929c055c
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
Description
Résumé:‘Honeycrisp’ (<i>Malus domestica</i> Borkh.), a premium applecultivar, is highly susceptible to bitter pit and decline in quality during long-term storage. In order to enhance the quality, an aqueous composition containing hexanal was applied as a preharvest spray. The effects of hexanal were assessed on the treated fruit and compared with Harvista<sup>TM</sup> (a sprayable 1-Methylcyclopropene based commercial formulation) applied and control fruit under both cold (2.5 °C; four months) and cold after room temperature storage (20 °C; 14 days) conditions. Color, firmness, and total soluble solids (TSS) did not show a significant change in response to any treatment at harvest, while abscisic acid (ABA) significantly reduced and tryptophan increased in response to hexanal, compared to Harvista<sup>TM</sup> and control. The treatment effects on quality traits were observed during storage. Both hexanal and Harvista<sup>TM</sup> sprayed apples had higher TSS under both cold and room temperature storage. In addition, both sprays enhanced firmness at room temperature storage. However, the effects of sprays on other quality traits showed a different pattern. Apples sprayed with hexanal had lower phospholipase D enzyme (PLD) activity, lower incidence of bitter pit, and decreased expression of <i>MdPLDα1</i> compared to Harvista<sup>TM</sup> and control. On the other hand, Harvista<sup>TM</sup> treated fruit produced lower ethylene. Both sprays decreased the expression of <i>MdPLDα4, MdCaM2, MdCaM4</i> and <i>MdCML18</i> genes. Generally, PLD alpha has a direct role in promoting fruit senescence, whereas the calcium senor proteins (CaM/CMLs) may involve in fruit ripening process via calcium and ethylene interactions. Therefore, improved postharvest qualities, including the lower incidence of bitter pit in hexanal treated ‘Honeycrisp’, may be associated with lower membrane damage due to lower PLD enzyme activity and decreased expression of <i>MdPLDα1</i> and <i>MdPLDα4</i> genes throughout the storage period.