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.

Four kinds of fresh sweet oranges were obtained in the same season, November 2000, in Guangzhou. Citrus sinensis var. Hongjiang (called 'hong jiang chen' in Chinese) and C. sinensis Osbeck var. Anliu (called 'luo gang chen') were obtained at an orchard in Luo gang in Guangzhou (25 km from the center of Guangzhou). Citrus sinensis var. Sihui (called 'sihui ju') was harvested at the Shigou Experimental Farm in Sihui City in Guangdong Province (75 km far away from Guangzhou). Citrus sinensis var. Washington navel (called 'qi chen') which was produced in Jiangxi Province (200 km from Guangzhou; bordering Guangdong Province), was purchased at the wholesale market in Guangzhou. All oranges were kept in a cold room until prepared a few days later.

The peel oil compositions of four kinds of sweet oranges in China, Citrus sinensis Osbeck var. Hongjian, C. sinensis Osbeck var. Anliu, C. sinensis Osbeck var. Sihui and C. sinensis Osbeck var. Washington navel, were investigated by GC and GC/MS. The essential oils were extracted by cold-pressing method. Forty-two to 53 compounds were quantitatively determined for each variety. Their percentages, respectively, were: > 97.3%, > 98.4%, > 97.5% and > 98.0% in hydrocarbons; > 1.5%, > 0.7%, > 0.8% and > 0.9% in total aldehydes; 0.8%, 0.5%, 0.5% and 0.5% in alcohols. Either cis-or trans-limonene oxide was detected in small amounts in each of the four samples, with Hongjiang containing both limonene oxides. delta-3-Carene was commonly quantified at a level of 0.1% in all the samples. The content of aliphatic aldehydes, including octanal, nonanal, decanal and dodecanal, exceeded that of terpene aldehydes, such as neral and geranial in Hongjiang (0.9%) and Washington navel (0.6%), whereas the aliphatic aldehydes in Anliu and Sihui were present to a lesser degree than the terpene aldehydes. Either alpha- or beta-sinensal was detected in trace amounts in each of the four samples. Linalool was the major alcohol in all the samples. Nootkatone was not detected.

Unripe fruits of M. pomifera were collected on the tree from a hedge in August 1999 located on state-owned land in Boone County, IA. Ripe fruits were collected from the ground at the same hedge in October 1999.

The most notable difference between the unripe and ripe fruits was the increase in hexyl hexanoate in the ripe fruit. Gamma-Cadinene and alpha-cubebene were the most abundant sesquiterpenoids.

The 36 'Genovese' and 24 'Foglia di Lattuga' samples preliminarily analysed were grown in Tavazzano (MI), and harvested at flowering, from 5th to 10th August 1998. The breeding program started in 1999, by crossing several selected lines of 'Genovese' with 'Foglia di Lattuga' and 'Compatto'. Selected F1 plants were selfpollinated in 2000. Plants of the F2 (2001), F3 (2002) and F4 (2003) generations were selected on the basis of agronomic and morphologic traits, and self-pollinated. Only the seeds from self pollinated plants with satisfactory essential oil content and composition were used to obtain the next generation. In 2004, some F4 plants were replanted in order to evaluate their stability in relation to environmental variations. All leaf harvests were carried out at flowering.

Genovese' showed higher essential oil and linalool content, with almost total absence of methyl chavicol, very abundant in 'Foglia di Lattuga'.

The study was conducted in North-Central Anatolia under semi arid conditions. Seeds of 18 basil landraces (O. basilicum L.) were collected from local farms and home gardens in Turkey. To examine essential oil composition of the basil landraces without environmental influences, the plants were grown under identical (same environmental and soil conditions) conditions. Seeds were sown on a medium (1:1:1 washed sand, horse manure and field soil) in greenhouse conditions on March 25, 2003. Seedlings were grown until the 3-5 leaf stage. The seedlings were transplanted into pilots in the Gaziosmanpasxa University Experimental Research Station on May 15, 2003. The plants were harvested at the full blooming stage and dried at 35 ℃ for essential oil isolation.

Variation of essential oils in the landraces was subjected to cluster analysis, and seven different chemotypes were identified. They were (1) linalool, (2) methyl cinnamate, (3) methyl cinnamate/linalool, (4) methyl eugenol, (5) citral, (6) methyl chavicol (estragol), and (7) methyl chavicol/citral. Methyl chavicol with high citral contents (methyl chavicol/citral) can be considered as a 'new chemotype' in the Turkish basils.

Plant materials were collected from Chalous Road (north of Tehran province) both at the flowering stage in June and the seed stage in September 2003. The fresh plants were dried at room temperature. Dried stems/leaves (S/L) (collected during flowering stage), seeds (S) were hydrodistilled for 3 h in a Clevenger-type apparatus to produce the oils.

The major constituent in the stem/leaf oil was trans-alpha-bergamotene (77.1%), whereas the major constituent of the seed oil was pregeijerene (87.0%). Nonadecane (8.6%) were the other major constituents in the stem/leaf.

Aerial parts of Solidago virgaurea plants were randomly collected from the wild at two different altitudes, as described below, during the 2000 vegetation period. All the collections of the plant samples were carried out during massive bud formation and the beginning of flowering stage. Sample # 1, LTS00-46; 10 kg of the sample was collected on July 31, 2000 at LAT: 51° 07′ LON: 81° 10′ HEI 290 m from Altai land, Lokteev district, near the village of NovoMikhaylovskoe, on the left bank of the Aley River, outskirts of pine forest, fire area, sandy soils. Sample # 2, LTS00-57; 5.6 kg of the sample was collected on August 3, 2000 at LAT 51° 14′ LON 82° 28′ HEI 650 m from Altai land, Kur'in district, around the Kolyvanm quarries, with diverse turf grasses, along the river bank of Aley.

The main components from 290 m were alpha-pinene (36.5%), myrcene (14.8%), beta-caryophyllene (10.5%), germacrene D (8.2%), beta-pinene (7.1%) and limonene+beta-phellandrene (6.4%). The oil from the sample collected at 650 m had benzyl benzoate (57.0%), beta-caryophyllene (6.3%), germacrene D (6.0%), alpha-pinene (4.4%) and alpha-humulene (4.0%) as major components, suggesting polymorphism or the existence of different chemoytpes.

The aerial parts of T. flavum were collected in different periods from December to July 2006, from plants growing along the Ionic coast of Sicily (Italy). LF 1-LF 2-LF 3: represent the composition of leaf oils of plant samples collected in December (vegetative stage), February (pre-flowering stage) and April (budding stage) respectively; FL: flower oil; FR: fruit oil.

Some components, in all investigated plant parts, remained more or less constant during all the different phases of the plant cycle life. Worthy of note, considering the leaf oils, was that beta-pinene, limonene and germacrene D increased in the pre-flowering stage, while a series of esters and alpha-copaene, beta-caryophyllene, viridiflorol, Tmuurolol and phytol increased in the budding stage (LF3); the vegetative stage oil is generally characterized by a rich chemical composition and some constituents such as isoamyl hexanoate, alpha-humulene, bicyclogermacrene, beta-bisabolene and alpha-bisabolol reached their highest levels in this oil. In the flower oil, linalool and 1-octen-3-yl acetate were the main components compared to the amounts found in the other oils. Fruit oil composition was relatively oil poor, with beta-bisabolene, caryophyllene oxide, cadin-4-en-1-ol and phytone as the major constituents.

Herbal parts were collected from A = Eskisehir: Suluagac village in Turkey, altitude 1100 m, in July 1990 and B = Corum: Osmancik, Berk village in Turkey, altitude 580-600 m, on 22 June 1993.

One chemotype (Suluagac village, Eskisehir, Turkey) contained carvacrol (21.59%), p-cymene (17.80%) and thymol (14.10%); and the other chemotype (Berk village, Corum, Turkey) contained alpha-terpinyl acetate (23.80%), borneol (12.85%), linalool (13.67%) and thymol (11.31%) as major constituents.

Aerial parts of the plants with distinct odors, harvested at full flowering stage, were collected from the same population (growing in an area of one m²) on Mt. Parnis Attiki, at an altitude of 1200 m in June 1995.

Limonene (18.7%) and thymol (19.4%); geraniol (56.8%) and geranyl acetate (7.6%); linalool (63.1%) and alpha-terpinyl acetate (20.4%) were the predominant components in each of the three different chemotypes, respectively.