In vitro cultivation of Arabidopsis wildtype and mutant plants: Seeds were sterilized according to standard lab routines (EtOH, NaOCl/NaOH) prior to aseptical (in vitro) cultivation in 500 ml screw cap jars on MS medium (4.3 g/l; 50 ml/jar) containing Bacto- and Phytoagar (1:2; 6 g/l) and 30 g/l sucrose. Ten seeds were pipetted into each jar and plants grown for 6 weeks until flowering at a temperature of 20 ℃ under a 16/8 h day/ night regime using fluorescent tubes (Osram Lumilux Plus Eco 36 W). Both Arabidopsis thaliana wildtype plants of ecotype Columbia-0 (Col) and 4 Col-derived T-DNA knock-out mutants (homozygous lines) showing deficiencies in the GLS biosynthesis pathway were used in this study (five parallels for wildtype and mutants): TGG1 (Atg526000; Salk_130469), TGG2 (At5g25980; Salk_038730), Cyp83A1 (At4g13770) and Cyp83B1 (At4g31500; Salk_028573). Greenhouse-cultivation of Arabidopsis ecotypes: The following Arabidopsis ecotypes were used in the study: Columbia (Col), Cape Verde Islands (Cvi), Landsberg erecta (Ler) and Wassilewskija (Ws). Single plants were greenhouse-cultivated on fertilized soil (P-Jord; Emmaljunga Torvmull AB) in plug trays (9 × 6 cells) at a temperature of 20 ℃ (three parallels for each ecotype). Due to the 6-weeks growth period (November/December 2003), the plants were cultivated under a 16/8 h day/night regime using metal halide lamps (Osram HQI-T 400 W) placed 130 cm above the trays. Depending on the ecotypical plant development, whole plants were sampled after 3-4 weeks right before bolting for in vivo studies, while investigations of single plant organs (leaf, stem, inflorescence) were carried out after 5-6 weeks of cultivation.

Metabolites from methionine, leucine and phenylalanine-derived glucosinolates were most abundant (4-methylthiobutyl, 4-methylpentyl, 2-phenylethyl). In addition, 24 monoterpenes, 26 sesquiterpenes and 12 aromatic structures, predominantly observed in inflorescenses, are described. Excluding the vast group of straight chain aliphatic structures, a total of 102 volatile compounds were detected, of which 59 are reported in Arabidopsis thaliana for the first time, thus emphasizing the sensitivity and applicability of solid-phase microextraction for volatile profiling of plant secondary metabolites.

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.

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.

Grape pomaces and stalks of Nero d'Avola and Frappato were donated by the ''Valle dell'Acate'' wine firm, Acate, RG, Italy - those from Nerello Mascalese and Cabernet Sauvignon were given by the ''Emanuele Scammacca Barone del Murgo'' wine firm, Santa Venerina, CT, Italy. The winemaking procedures were similar for all samples, namely grape clusters were crushed and destemmed using a destemmer-crusher. The crushed grapes were treated with sulphur dioxide (0.2-0.5% total mash) and with selected strains of Saccharomyces cerevisiae to start up the fermentation. After 6-8 days of maceration, when alcoholic fermentation was finished, the mash was pressed. Stalks coming from destemming procedure and grape pomace coming from the maceration procedure were subjected to the distillation procedures within 24 h of their collection. All materials were collected during the 2004 vintage.

On the whole, 38 components have been characterized in the samples of grape pomaces, with Frappato cv. showing the richest composition; instead, 88 components have been detected in the stalks of Frappato, Nero d'Avola, Nerello Mascalese and Cabernet Sauvignon varieties.