Chiu, G. Z., Shelp, B. J., Bowley, S. R., DeEll, J. R. and Bozzo, G. G. 2015. Controlled atmosphere-related injury in ‘Honeycrisp’ apples is associated with γ-aminobutyrate accumulation. Can. J. Plant Sci. 95: 879-886. ‘Honeycrisp’ apples (Malus×domestica Borkh.), including fruit treated with the ethylene antagonist 1-methylcyclopropene (1-MCP), can be susceptible to controlled atmosphere (CA)-related injury of the flesh tissue during storage. To better understand the biomarkers associated with this physiological disorder, we compared the temporal responses of the universal stress signature, γ-aminobutyrate (GABA), and visual symptoms of CA-related injury in apples subjected to elevated CO2. Fruit were treated with or without 1-MCP prior to CA [2.5 kPa O2, 5 (elevated) or 0.03 (ambient) kPa CO2] storage at either 3 or 20°C for up to 24 wk. At 20°C, 1-MCP-treated apples displayed symptoms of CA-related injury by 3 wk of elevated CO2 storage; a similar 15% disorder incidence was apparent by 6 wk in non 1-MC...