Genetic improvement of vase life of carnation flowers by crossing and selection

We used conventional cross-breeding techniques to develop many carnation li nes with long vase life and either low ethylene production or low ethylene sensitivity. Two cycles of selection and crossing to improve vase life led to a 3.6-day increase in mean vase life. All 39 selected lines had signific antly longer vase life than the control cultivar, 'White Sim'. In particula r, second-generation lines 63-3, 63-12, 66-15, and 63-41 had a mean vase li fe of more than 15 days without chemical treatment. Measurements of ethylen e production indicated that flowers of all second-generation selected lines had a greatly reduced capacity to produce ethylene. We screened three line s (515-10, 64-13, and 64-54) with low ethylene sensitivity. Evaluation by e xposure to ethylene at high concentration showed that 64-13 and 64-54 were less sensitive to ethylene than 'Chinera', which is known for it low sensit ivity. The vase life of these low-sensitivity lines was about twice that of 'White Sim'. The extended vase life of selected lines was related to low e thylene production at flower senescence rather than to degree of ethylene s ensitivity in young flowers. Ethylene sensitivity decreased with the age of the flower in many selected lines. The results clearly show that vase Life of carnation flowers can be extended by crossing and selection. (C) 2001 E lsevier Science B.V. All rights reserved.