2011 Volume 80 Issue 2 Pages 175-181
Most modern carnation (Dianthus caryophyllus L.) cultivars tend to have little fragrance. Wild Dianthus species having a strong or characteristic fragrance were thought to be promising genomes for the introduction of fragrance into these modern carnation cultivars. We selected 10 plants with fragrant flowers and 1 hardly fragrant plant, which was used as a negative fragrant control, from wild Dianthus gene resources of National Institute of Floriculture Science, and divided them into 4 groups according to their sensory characteristics. Gas chromatography-mass spectrometry (GC-MS) analysis indicated that the scent compounds of wild Dianthus species were principally composed of 18 volatile compounds, which were benzenoids, terpenoids, or fatty acid derivatives. The sweet and medicinal fragrance of Group 1, having the strongest scent, was due to methyl salicylate, a benzenoid. The citrus-like fragrance of Group 2 was due to β-ocimene and β-caryophyllene, two terpenoids. The green leafy odor of Group 3 was due to (Z)-3-hexenyl acetate, a fatty acid derivative. In Group 4 flower, which had little fragrance, scent compounds were hardly detected. In theses flowers, the composition of the emitted scent compounds differed from that of the endogenous scent compounds; the scent compounds, having a high vapor pressure and a relatively low boiling point, were efficiently emitted from the flower organs. Major benzenoids in D. hungaricus of Group 1 were distributed in petal limbs, and major terpenoids in D. superbus of Group 2 and major fatty acid derivatives in D. sp. 2 of Group 3 were distributed in petal bottoms and collectively, in the stamens and pistil. These results demonstrate that the floral tissues which produce fragrance differ for each Dianthus species. In this study, Group 1, being rich in methyl salicylate, and Group 2, being rich in β-ocimene and β-caryophyllene, were suggested important gene resources for introducing fragrance into carnations because these scent compounds have a pleasant smell and contribute strongly to the fragrance features of their respective flowers.
