Reduced ethylene production in transgenic carnations transformed with ACC oxidase cDNA in sense orientation

Abstract: 'Lillipot' carnation, which is usually cultivated as a potted ornamental, was transformed with a cDNA for carnation 1-aminocyclopropane-1-carboxylate (ACC) oxidase. Two lines, which harbor an sACO transgene, had a vase life of cut flowers more than twice longer than that of the non-transformed (NT) control. Flowers of the long vase life lines senesced with discoloring and browning in petal margins, which is typical to ethylene-independent senescence in carnation flowers. They produced negligible amount of ethylene for the first 8 day, whereas flowers of the NT control showed a climacteric ethylene production with a maximum on day 3. Transcripts for DC-ACS1 and DC-ACO1 were absent in petals of the long vase life flowers undergoing senescence. The present study revealed that transformation with sACO transgene may be useful to generate potted carnation plants with a long display time.