Plants of the F. imperialis cultivars Premier (very strong foxy odor) and Lutea (strong foxy odor), the F. imperialis subspecies Inodora (no odor), a cross between F. imperialis Lutea × Inodora (F1 generation, faint foxy odor) were grown from bulbs during the spring and early summer in clay soil near Midlum (Province of Friesland, The Netherlands). Bulbs, newly grown from these plants, were harvested in mid-June and stored, after removal of soil, at ambient temperature until analysis, which occurred in October and November.

GC-O revealed that the foxy odor was caused by a single component, identified as 3-methyl-2-butene-1-thiol on the basis of smell in GC-O analyses (two GC columns), mass spectra, and retention times. The abundance of 3-methyl-2-butene-1-thiol is consistent with the intensity of foxy Fritillaria odor in the F. imperialis cultivars: Premier > Lutea >> Lutea × Inodora, where the latter did not show a detectable peak in GC-MS.

The plant material was collected in eastern Lithuania (July-August, 2002). Numbers of growing localities of H. arenarium with yellow (Y) and orange (O) flowers were as follows: Svencionys district (Zalavas) and Ukmerge district (Sventupe).

The 68 constituents identified comprised 73.8-90.7% of the total oil content. It was found that the principal constituents were: beta-caryophyllene (in three inflorescence and one leaf oil), delta-cadinene (in two leaf oils), octadecane (in one leaf oil) and heneicosane (in one inflorescence sample). Monoterpenes and oxygenated monoterpenes made up 4.0-13.9%, aliphatic hydrocarbons 0.4-35.3%, and sesquiterpenes 24.7-71.2% of the oils.

Seeds of P. ruderale were collected from wild plants found on the campus of the Federal University of Vicosa, Minas Gerais state (Brazil), in September 2000. The seeds were cultivated in a greenhouse during the period of February to May 2001; 60 days after sowing, the leaves and flowers were collected at regular intervals of 15 days for the oil isolation.

The oil content found for the leaves of P. ruderale varied during the period of 60 to 120 days, as follows: 13.8 mg/100 g of fresh material after 60 days; 7.5 mg/100 g (75 days); 23.1 mg/100 g (90 days); 10.6 mg/100 g (105 days); 12.5 mg/100 g (120 days). The first floral buds were collected after 105 days of sowing, and its oil content was 45.1 mg/100 g of fresh material. A significant decrease in the production of oil from the buds was observed after 120 days of sowing, when only 23.0 mg oil/100 g of fresh material was obtained. During the period of 90 days to 105 days, a significant decrease in leaf oil content was observed, at the same time the plants were flowering. This data suggests the plants were relocating their resources to produce more oil in the floral buds.

Experimental site: The present study was conducted at the experimental farm of the CSIR-Institute of Himalayan Bioresource Technology, Palampur (1325 m amsl, 32° 06′ 05″ N, 76° 34′10″ E), India, in 2011. Minimum temperature ranges from 3.5 ℃ to 19.8 ℃, maximum temperature ranges from 15.2 ℃ to 31.4 ℃, relative humidity varies between 62.2% and 94.1% in the morning and 45.0% and 87.2% in the evening, and bright sunshine hour ranges from 2.9 to 8.9 hours. Plant material: A population of approximately 50,000 plants raised from mixed stem cuttings collected from perennial rose plantations at the University of Agriculture, Udaipur, Rajasthan, India, and maintained in the field of the CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh, India, were utilized as an original gene pool of R. damascena. Two varieties, Jwala and Himroz were diversified through selections of desirable traits (morphological/oil content) across 25,000 plants. The five elites, three of R. damascena var. Jwala, (Indica, Super jwala and Jwala) and two of R. damascena var. Himroz (Hot himroz and Himroz) were developed through field selections and maintained at the Natural Plant Products Division Experimental Farm of the Institute. Rosa bourboniana plants were collected from the Fragrance and Flavour Development Centre, Kannauj, UP, India, during 1992 and maintained at the Natural Plant Products Division Experimental Farm of the Institute.

The essential oil content of the varieties of R. damascena varied from 0.037% to 0.051% and that of R. bourboniana was 0.017%. Super jwala recorded the highest oil content (0.051%). A total of 32 components were identified in the different varieties of rose oil. These components constituted 78.1-93.5% of the total rose oil species. The main components of rose oil were citronellol + nerol (16.3-30.1%), geraniol (15.8-29.3%), linalool (0.7-1.9%), rose oxide (0.9-2.6%), phenyl ethyl alcohol (0.1-0.4%), eugenol (0.3-2.2%), nonadecane (7.3-14.7%). The content of citronellol + nerol (30.1%) and geraniol (29.3%) was the highest in Himroz compared with other varieties.