title: Emission mechanism of floral scent in Petunia axillaris.
abstract: The mechanism of floral scent emission was studied in Petunia axillaris, a plant with a diurnal rhythm of scent output. The emission rate of each volatile compound oscillated in synchrony with its endogenous concentration, so that the intensity of the floral scent appeared to be determined by the endogenous concentrations. The composition of major volatiles in the flower tissue and the flower headspace showed characteristic differences. A negative correlation was found between the boiling points of the volatile compounds and the ratio of their emitted and endogenous concentrations, indicating that the composition of the floral scent depends directly on the endogenous composition of the volatile compounds. We conclude that in P. axillaris, the physiological regulation of floral scent emission operates not in the vaporization process but in the control of the endogenous concentrations of volatiles through biosynthesis and metabolic conversion.
authors.affiliation: Department of Genetics and Physiology, National Institute of Floricultural Science, National Agricultural and Bio-oriented Research Organization, Ibaraki 305-8519, Japan. namisea1@affrc.go.jp
authors.forename: Naomi
authors.initials: N
authors.lastname: Oyama-Okubo
authors.forename: Toshio
authors.initials: T
authors.lastname: Ando
authors.forename: Naoharu
authors.initials: N
authors.lastname: Watanabe
authors.forename: Eduardo
authors.initials: E
authors.lastname: Marchesi
authors.forename: Kenichi
authors.initials: K
authors.lastname: Uchida
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Nakayama
mesh_terms: D002940:Circadian Rhythm / Q000502:physiology; D035264:Flowers / Q000737:chemistry / Q000378:metabolism*; D009812:Odorants / Q000032:analysis; D032306:Petunia / Q000737:chemistry / Q000378:metabolism*; D013997:Time Factors; D044366:Transition Temperature; D014835:Volatilization