The effects of modified atmosphere (MA) and 1-methylcyclopropene (1-MCP) on the quality and longevity of florets were investigated in potted carnation ‘Scarlet’. MA with and without 1 μL·L
−1 1-MCP (2 day-exposure) for whole plant at 22/17°C significantly delayed the peak of ethylene and wilting of florets, and prolonged the display life from 7.0 to 9.4 days after harvest (DAH). In the experiment for cut florets, active MA (a-MA; initial gas, 2.75% for CO
2 and 11.5% for O
2) for 2 days prolonged the longevity from 5.5 to 7.8 days, whereas a-MA in combination with the 1-MCP (a-MA/MCP) treatments prolonged longevity to 12.5 days. Maximum ethylene production was decreased from 58.3 to 9.8 nL·g
−1·h
−1 by a-MA, while only trace amounts was detected in a-MA/MCP. In the gynoecium, a-MA repressed
DcACS2 (1-aminocyclopropene-1-carboxylate synthase) expression throughout the experiment and
DcACS3 until 4 DAH. The a-MA also repressed
DcACO1 (ACC oxidase) until 6 DAH, whereas a-MA/MCP completely repressed
DcACO1. In the petals, a-MA/MCP repressed
DcACS2 and
DcACS3. The both treatments significantly lowered respiration rate of florets on 8 DAH, and increased contents of soluble carbohydrates in petals on 4 DAH. These results indicate the combination of MA and 1-MCP is more effective than MA alone in the reduction of ethylene production, respiration and the expressions of
DcACS2 and
DcACO1, and maintained soluble carbohydrates, and thus improved postharvest qualities compared to the single treatments.
View full abstract