The control of rhythmic emission of floral volatiles emitted from Rosa damascena semperflorens cv. 'Quatre Saisons' throughout floral development under various light regimes was studied. 2-Phenylethanol was the major volatile emitted in addition to monoterpenols, oxidised monoterpenols, monoterpenes and aromatic compounds. All detected volatiles were emitted rhythmically, with maximum peaks coinciding 8-10 h into a 12-h photoperiod. For some compounds a secondary, nocturnal peak was apparent. The primary and secondary maxima both occurred at approximately 24-h intervals. Rhythms appeared to be regulated endogenously: rhythmic emission continued upon exposure to continuous light or continuous darkness, and a phase shift in emission was induced upon inversion of the photoperiod. Additionally, emission continued after flower excision. A similar profile of free volatiles was stored within the floral tissue, together with glycosidic forms of 2-phenylethanol (>99% beta-D-glucoside), benzyl alcohol, citronellol and geraniol. Regression analysis indicated a significant decrease in glycosylated 2-phenylethanol through the photoperiod. These results suggest that glycosylated volatiles stored within petals may be a source of rhythmically emitted volatiles.

Cypriol oil, the essential oil from Cyperus scariosus R.Br., has been investigated to reveal minor nitrogen-containing molecules and minor components responsible for the odor. A total of 21 nitrogenous components are reported, of which epi-guaipyridine (32 mg/kg), guaia-9,11-dienpyridine (9 mg/kg), and cananodine (10 mg/kg) were the most abundant. A new ketone, cyperen-8-one, with a significant woody, ambery odor could also be isolated and identified along with a novel lactone, cyperolactone, and an alcohol. Rotundone was found to have the highest odor-activity value of the measured compounds and, together with the other ketones, contributes to the woody-amber character of cypriol oil.

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Three horticultural selections of Acorus gramineus Soland were investigated to determine the chemical composition of their leaves and rhizomes. The variety 'liquorice' was found to contain methylchavicol (49%) which accounts for the unusual anisic odor of this variety, while beta-asarone was the main component of A. christophii (43%) and 'yodo-no-yuki' (20%). The results are compared with calamus oils, and the possible biosynthetic precursors of the main components methylchavicol and beta-asarone are considered.

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The oils of Achilles coarctata Poir and Aclzillea oligoceplzala DC. were analyzed by GC and GCIMS. The oil of A. coarctata Poir contained 1,8-cineole (20.1%), camphor (15.6%) and viridiflorol (11.8 %), while the oil of A. oligocepliala DC. contained 1,8-cineole (18.6%), a-terpineol(fi.X%) and lindool (6.0%) as inajor Components.