Marcin Glowacz1,2, Malick Bill2, Peter P Tinyane2, Dharini Sivakumar2. 1. Natural Resources Institute, University of Greenwich, Chatham, UK. 2. Postharvest Technology Group, Department of Crop Sciences, Tshwane University of Technology, Pretoria West, South Africa.
Abstract
BACKGROUND: Low temperatures are often used to reduce metabolic processes and extend the storage life of fruit; however, in the case of avocado, a temperature below 3 °C will often result in the development of physiological disorders associated with chilling injury. The objective of this study was to investigate the ability of methyl jasmonate (MeJA) and methyl salicylate (MeSA) vapours to alleviate chilling injury in 'Hass' avocado fruit kept at 2 °C for 21 days followed by 6-7 days of shelf-life at 20 °C, simulating supply chain conditions. RESULTS: The incidence and severity of chilling injury were significantly reduced in MeJA- and MeSA-exposed fruit, especially at 100 µmol L-1 . The mechanism involved improved membrane integrity via alteration of the fatty acid content and composition, down-regulation of LOX gene expression and reduced activity of lipoxygenase. CONCLUSION: MeJA and MeSA have the potential for being used with 'Hass' avocado fruit shipped at low temperature to reduce its susceptibility to chilling injury.
BACKGROUND: Low temperatures are often used to reduce metabolic processes and extend the storage life of fruit; however, in the case of avocado, a temperature below 3 °C will often result in the development of physiological disorders associated with chilling injury. The objective of this study was to investigate the ability of methyl jasmonate (MeJA) and methyl salicylate (MeSA) vapours to alleviate chilling injury in 'Hass' avocado fruit kept at 2 °C for 21 days followed by 6-7 days of shelf-life at 20 °C, simulating supply chain conditions. RESULTS: The incidence and severity of chilling injury were significantly reduced in MeJA- and MeSA-exposed fruit, especially at 100 µmol L-1 . The mechanism involved improved membrane integrity via alteration of the fatty acid content and composition, down-regulation of LOX gene expression and reduced activity of lipoxygenase. CONCLUSION:MeJA and MeSA have the potential for being used with 'Hass' avocado fruit shipped at low temperature to reduce its susceptibility to chilling injury.