Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: 5/23/2017
Publication Date: N/A
Citation: N/A Interpretive Summary:
Technical Abstract: Postharvest management of apple fruit ripening using controlled atmosphere (CA) cold storage can be enhanced as CA oxygen concentration is decreased to close to the anaerobic compensation point (ACP). Monitoring fruit chlorophyll fluorescence is one technology available to assess fruit response to low O2 CA conditions while avoiding anaerobiosis. As apple fruit response to CA is also determined in part by CO2 concentration, studies were conducted with ‘Golden Delicious’ and ‘Honeycrisp’ to examine fruit response to O2 storage conditions at or near the ACP with various CO2 concentrations. ‘Golden Delicious’ apples were held at 0.5 oC for 48 h after harvest during which time some fruit were exposed to 42 µmol L-1 1-methylcyclopropene. CA was established by 96 h after receipt. Fruit chlorophyll fluorescence increased when O2 kPa decreased to ~0.3. ‘Golden Delicious’ fruit developed external and internal disorders when stored in CA with 5 kPa CO2. CF did not change during storage although injury occurred. Disorder incidence increased as O2 concentration decreased and with 1-MCP treatment. Some aspects of fruit quality were enhanced as CA O2 decreased. ‘Honeycrisp’ fruit were held 7 d at 10 oC then at 2.8 oC. Some fruit were exposed to 42 µmol L-1 1-MCP the day of receipt. CA was established 48 h after transfer to 2.8 oC. Fruit chlorophyll fluorescence increased when O2 kPa decreased to ~0.3 kPa O2. Internal disorder incidence increased as CA O2 decreased and also with 1-MCP use. CF did not change during storage. Some aspects of fruit quality were enhanced by storage in lower O2. Low O2 did not impact incidence of low temperature disorders. Results indicate some aspects of fruit quality for both cultivars are enhanced by storage in the lowest O2 concentrations although CF may not provide an indication of fruit stress that can result in physiological disorder development.