Near-anoxia, hypoxia, and 1-methylcyclopropene improve long-term storage potential of 'Cortland' and 'McIntosh' apples

The potential of oxygen and temperature acclimation using sequential controlled atmosphere (SeCA), or Initial Low Oxygen Stress (ILOS) and 1-methylcyclopropene (1-MCP) was investigated to improve quality retention in 'Cortland' and 'McIntosh', two apple cultivars poorly adapted to long-term storage. Good firmness retention and few storage disorders were evident in 'McIntosh' after 174 days storage in SeCA (O2 and CO 2 approximately halved every 58 days) in which temperature also was lowered from 3°C to 0°C. With 'Cortland' apples a combination of ILOS and 1-MCP resulted in retention of harvest firmness and extremely low incidence of physiological disorders, especially superficial scald. Quebec-grown 'Cortland' stored continuously at 0°C developed low temperature breakdown (LTB). Neither 1-MCP nor ILOS prevented its development. However, in 'McIntosh' an acclimation period of at least 30 days at 3° prior to storage at 0°C successfully inhibited development of LTB and also eliminated core browning, a low temperature-related disorder.