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.

The aerial parts of T. chamaedrys were collected at the flowering stage in June 2004 near Corti, Corsica, France and near Oristano, Sardinia, Italy

The Corsican and Sardinian oils of T. chamaedrys investigated in this study were qualitatively similar but they differed by the amount of their major components. The major components were beta-caryophyllene (29.0% and 27.4%, respectively) and germacrene D (19.4% and 13.5%, respectively), followed by alpha-humulene (6.8%) and delta-cadinene (5.4%) in the Corsican oil and by caryophyllene oxide (12.3%) and alpha-humulene (6.5%) in the Sardinian oil. These quantitative differences are also noticeable on the amounts of the different class compounds. Especially, the monoterpene hydrocarbons amounted for 10.3% and 4.1% in Sardinian and Corsican oils respectively and the oxygenated sesquiterpenes amounted for 18.9% and only 7.4% in both oils, respectively. Both oils were qualitatively rather similar in comparison with those reported in the literature from various geographic regions. However, among the 87 components identified in this study, 47 minor components (< 0.6%) reported were identified for the first time in T. chamaedrys oil. This study confirms the quantitative variability of the major components according to the plant origin.

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.

3-year old single shoot V. vinifera plants (cultivar Pinot noir 18 Gm grafted on Kober 5BB, 51 plants) potted in 3L pots in a sandy loam soil were used. All plants were well watered (200 mL per day) at the beginning of the experiment (04.06.2010; DAY 0; 5 plants) and water was supplied to all control plants once every day (250 mL per day), whereas water supply of stressed plants was stopped. Physiological measurements and sampling of leaves took place on 07.06.2010 (DAY 3; 5 control, 5 stressed plants), 10.06.2010 (DAY 6; 5 control, 5 stressed plants) and 12.06.2010 (DAY 8; 5 control, 10 stressed plants). Due to very hot weather conditions in June 2010 the experiment was stopped after 8 days and 12 available control plants were used to restart the drought treatment with 6 control and 6 stressed plants on 11.06.2010 and all plants were measured on 15.06.2010 (DAY 5). The mean leaf temperatures at midday were: 25 ℃ (04.06.2010; DAY 0), 31.9 ℃ (07.06.2010; DAY 3), 30.8 ℃ (15.06.2010; DAY 5), 35.8 ℃ (10.06.2010; DAY 6) and 35.7 ℃ (12.06.2010; DAY 8). The mean PAR radiation per day (measured from 6:00 am till 7:00 pm) was 144.1 µmol m^-2 s^-1. Each plant was used only once for physiological measurements and sampling of leaves.On every day of the experiment (day 0, 3, 5, 6, 8) the pot weight and the volumetric soil moisture content (ThetaProbe ML2x and handheld data logger Moisture Meter HH2, Delta-T Devices, Cambridge, United Kingdom) was recorded. The water potential (PWSC Model 3000, Soilmoisture Equipment Corporation, Santa Barbara, USA) was determined for the 6th leaf (representing the insertion level of the shoot from the basis) of every plant and measurement day. Chlorophyll fluorescence and gas exchange parameters of light adapted leaves were determined with the 4th and 5th leaf, whereas dark adaptation was performed only with the 5th leaf. Immediately after these non-invasive measurements, the 5th leaf was harvested, frozen in liquid nitrogen and further used for the measurement of polyphenols, selected primary metabolites and volatiles (VOCs).

The content of different groups of primary and secondary metabolites is significantly influenced by severe drought stress in grapevine leaves. The content of the majority of the metabolites (around 60% of primary metabolites, around 85% of polyphenols and about 40% of the detected and identified VOCs) increased upon drought stress treatment. Among these especially the primary metabolites citric acid and glyceric acid were strongly influenced by the short as well as the prolonged drought stress treatment, whereas all polyphenols were only induced upon the prolonged drought stress treatment.