Effects of anoxic and hypercarbic controlled atmospheres on anaerobic volatile emission and ethylene production from 'Klemaxi' and 'Doranja' carnation (Dianthus caryophyllus L.)

Anoxic and hypercarbic controlled atmospheres (CA) accelerated pigment loss, petal withering, and reduced display life of two carnation (Dianthus caryophyllus L.) cultivars ('Klemaxi' and 'Doranja') at 20 degrees C. Pigment loss and water-saturated appearance of the petals indicated a loss of membrane integrity, which may largely result in loss of display life in these CA treatments. This reduction in display life was found to be ethylene independent, as only air-treated flowers exhibited the characteristic climacteric rise in ethylene production. Flowers treated with hypercarbic CA before anoxic CA showed extended display life over flowers placed immediately in anoxic CA, indicating hypercarbic CA preconditioned the carnations to anoxia. Flowers with longer display life converted more acetaldehyde to ethanol during CA treatment. Thus, acetaldehyde accumulation may play a role in damaging carnations during hypercarbic and anoxic CA.