Aerial parts of endemic pichana were harvested in December 1996 at different localities of northern Patagonia. Origin: Planicie Banderita, Dept. Confluencia, Province of NeuquCn. Habitat: altitude, 327 m; average temperature in the station, 21.8 ℃; annual precipitation, 125 mm; sandy soils. Aerial parts (5 kg, 2 kg of dried material;humidity, 11%) from four well developed plants at the fullflowering stage (December, 1996). Sample 2 : Origin: RincBn de 10s; Sauces, Dept. of Pehuenclies, Province of Neuqukn. Habitat: altitude, 750 m; average temperature in the station, 20.9 ℃; annual precipitation, 147 mm; sandy and gritty salty soils. Aerial parts (5 kg, 1.85 kg of dried material, humidity, 10%), from two well developed plants at the full flowering stage, and after several days copious rains (December, 1996). Sample 3: Origin: Coronel GBmez, Dept. General Roca, Province of Rio Negro. Habitat: altitude, 242 m; average temperature in the station, 22.5 ℃; annual precipitation, 179 mm; sandy and stony soils. Aerial parts (4.5 kg, 1.3 kg of dried material, humidity, 9%), from 12 young plants at the beginning flowering stage (December, 1996).

Fifty-four components, representing approximately 84.6-97.4% of the oil samples, were identified. The samples consisted mainly of hydrocarbons and oxygenated monoterpenes. The major constituents were limonene (28.7-56.7%), 6R-7R-bisabolone (3.2-9.1%), sabinene (0.1-11.0%) and citronellal (2.4-5.2%). Significant differences among the content of the three samples could be the result of changes in the climatic conditions (sample 2: Rincon de los Sauces, Province of Neuquen, after strong rains) or by translocations in different parts of the plant (sample 3: Coronel Gomez, Province of Rio Negro, more leaves and less stems).

The aerial parts of D. assadii Alava. were collected in the wild from Lalehzar (Kerman Province, in southern Iran) at the flowering stage, in July 2007. The material was dried at room temperature and used for distillation. Distillation: A direct-fired field distillation unit containing a distillation tank (capacity: 1,000 L), a condensation column and receiver, all made of stainless steel, and which can process 30-50 kg of dried aerial parts from the plants/batch, was installed at an altitude of 2600 m (boiling point: 87 ℃). Dried aerial parts from the plants (40 kg) were charged into the distillation unit along with 500 L fresh water and the unit was heated by steam. The system was kept open to atmospheric pressure until the temperature reached to 70 ℃, when the air present in the unit was replaced by the vapor. After complete removal of air from the unit, the air vent was closed and the whole unit was operated as a closed system under pressure to distill the oil. The pressure, temperature and rate of distillation were controlled manually. The process was completed after the collection of 500 L of water distillate. The oil collected in the receiver and dried over anhydrous Na₂SO₄. Extraction of Ducrosia Second Oil From Ducrosia Water by Redistillation: The seprated distillate water collected in the receiver was redistilled in a 1,000 L still to yield more Doucrosia oil (this oil is known as secondary essential oil, second oil, cooked oil or indirect oil).

Fifty components were identified in a second oil of D. assadii from Lalehzar with decanal (35.2%), nonadecane (12%) and citronellyl acetate (11.6%) as the main constituents. The oil from Dehbakrii also contained decanal (36.4%) as the main component of an oil recovered from the distillate water. The results showed that the amount of decanal is remarkably high in the oils of D. assadii.

Plants were collected in the Inner plain, the Sharon plain and the kava valley.

The major constituent of all three oils was found to be 1,8-cineole (26.4-34.5%) followed by menthone (10.0-16.7%), pulegone (7.0-7.5%), and isomenthone (4.7-7.8%). Despite some differences in the component proportions, the plants of all three populations clearly belong to the same chemotype.

Peppermint plants were initiated from rhizome cuttings (10 cm long) supplied by Jahad Daneshgahi in March 2009. According to the method described by Farahani et al., (2009), seventy five peppermint samples were notified above were transferred into pots (25 cm head diameter × 20 cm height) filled with sandy loam soil (soil average amount of 5580 gr in each pot). This experiment was carried out using a randomized compllete block design with 3 replications. The factors studied included 5 levels of water deficit stress that were D1 (100% field capacity), D2 (85% field capacity), D3 (70% field capacity), D4 (60% field capacity) and D5 (45% field capacity), respectively. In order to determine the soil moisture rate of 100% field capacity, 24 h after irrigation we selected 5 field soil samples by sampling drill, then samples were weighed by electrical scale and placed under 105 ℃ in electrical oven for 48 h. Field soil samples were selected for determination of soil moisture rate daily, than determined 85% field capacity, 70% field capacity, 60% field capacity and 45% field capacity, respectively.

Results indicated that drought stress motivated a significant reduction in all of the growth parameters and essential oil yield and percent. The highest values of growth parameters and essential oil percent and yield were observed under 100% field capacity (control). Also, the highest values of Mentone and menthofuran were obtained under 100% field capacity (control) and the highest values of menthol were obtained under 70% field capacity by using gas chromatography-mass spectroscopy (GC-MS).

Dry leaves of Menlba piperita L. 'Kliment-63' and 'Zefir' of 1997 crop were used.

The oil yield from 'Zefir' was 0.97% and that from 'Kliment-63' was 0.54%. The oil from 'Zefir' was found to be rich in menthol (46.2-50.2%) and menthyl acetate (16.8-22.5%). In the oil from 'Kliment-63,' the content of these components was lower, while the menthone content was higher (20.0-23.1%).

The aerial parts of flowering Mentha pulegium plants (cut at ground level) and individual M. pulegium plants were collected in the summer (July, 2003) from three wild populations located in the Municipality of Laganas, Zakynthos, W. Greece. Location 1 (N 37° 41′ 29″, E 20° 50′ 25″; map datum WGS 84; altitude 3 m; 14/07/03) was close to Keri Beach (Limni Keriou), Location 2 (N 37° 43′ 34″, E 20° 50′ 41″; altitude 3 m; 13/07/03) was near the village of Kalamaki and Location 3 (N 37° 39′ 39″, E 20° 48′ 44″; altitude 160 m; 17/07/03) was near the village of Vasilikos. The three locations are within the mainland limits of the protected area of the National Marine Park of Zakynthos (NATURA 2000 Network, site GR 2210002; 14).

The composition of the inflorescence (I), leaf (L) and stem (S) essential oils of wild Mentha pulegium plants from three populations (1-3) on the island of Zakynthos were examined. Pulegone (32.8 %, S1 to 75.8 %, I3) was the major constituent of all of the oils. The other main constituents were piperitenone (5.1 %, L3 to 35 %, I2), isomenthone (4.3 %, I2 to 28.6 %, L3) and piperitone (0.5 %, I3 to 5.2 %, L2). In total, C-3-oxygenated p-menthane compounds constituted from 73.0 % (S1) to 96.2 % (I2) of the oils. The piperitenone content of the inforescence oils was up to 2.4 (Loc 3) times higher than that of the leaf oils. Correspondingly, the isomenthone content of the leaf oils was up to 4.2 (Loc 2) times higher than that of the inforescence oils. The ratio of the isomenthone:piperitenone content of the oils (n=3) was markedly different for the inforescence (mean 0.31), leaf (mean 2.91) and stem (mean 1.12) oils.

The aerial parts of flowering Mentha spicata plants (cut at ground level) and individual M. spicata plants were collected in the summer (July, 2003) from three wild populations located in the Municipality of Laganas, Zakynthos, W. Greece. Location 1 (N 37° 39′ 39″, E 20° 48′ 44″; map datum WGS 84; altitude 160 m; 14/07/03) was near the village of Keri, Location 2 (N 37° 41′ 29″, E 20° 50′ 25″; altitude 3 m; 14/07/03) was close to Keri Beach (Limni Keriou) and Location 3 (N 37° 43′ 34″, E 20° 50′ 41″; altitude 35 m; 14/07/03) was near the village of Pandocratoras. The three locations are within the mainland limits of the protected area of the National Marine Park of Zakynthos (NATURA 2000 Network, site GR 2210002; 8).

The main oil constituents were trans-piperitone oxide, piperitenone oxide and 1,8-cineole. On a whole plant basis (aerial parts) the trans-piperitone oxide content ranged from 1.4 % location (Loc 1) to 32.5% (Loc 3) and appeared to have an inverse relationship with the 1,8-cineole content which ranged from 10.8 % (Loc 3) to 37.9 % (Loc 1). 1,8-cineole was the major oil constituent (37.9 %) of M. spicata plants from Loc 1. The major constituent of the inflorescence oils was piperitenone oxide which ranged from 32.4 % (Loc 3) to 46.3 % of the oil (Loc 1). The major constituent of the leaf oils was 1,8-cineole (40.5 %) in plants from Loc 1 and trans-piperitone oxide in plants from Loc 2 (19.8 %) and Loc 3 (33.5 %). This is the first report for wild populations in Greece of a M. spicata oil in which 1,8-cineole is the major constituent. The observed variation in essential oil composition between locations and plant organs in July would not appear to be directly related to the climatic conditions.

The aerial parts of M. biflora collected during November 1993 and June 1994 were used for the investigation.

The major constituents of the oil were neral (25.3-32.2%) and geranial (26.7-41.3%). The oil produced in the winter was found to contain higher amounts of oxygenated monoterpenes than the oil produced in the summer.

The cultivars selected for this study are Sreekara, Vellanamban and one Indonesian cultivar Kutching grown in Kerala. These cultivars are commonly cultivated in the northern parts of Kerala. The fresh berries of the authenticated cultivars were collected from Indian Institute of Spices Research, Calicut and were dried in a cross flow drier at 45 ℃ and taken for the analysis.

The main components of vellanamban oil were sabinene (3.9-18.8%), beta-pinene (3.9-10.9%), limonene (8.3-19.8%) and beta-caryophyllene (28.4- 32.9%). Sreekara oil contained as major compounds beta-pinene (0-11.2%), limonene (20.1-22.1%) and beta-caryophyllene (16.8-23.1 %). Kutching oil contained alpha-pinene(2.3-5.4%), sabinene (6.7-13.3%), limonene (14.5-17.5%) and beta-caryophyllene (20.8-39.1%).

Seeds of Iranian native savory were obtained from the seed bank of the Research Institute of Forests and Rangelands, Tehran, Iran, and were sown in the field on 30 March 2000. Plants were 0.2 m apart with 0.5 m between rows. For the water stress study, each plot, four rows wide and 10 m long, with four replications in a randomized complete block design, was irrigated regularly with furrow irrigation. The timing of irrigation (frequency and duration) was based on the soil water potential, according to treatment criteria. Soil water potential was monitored using sensors and leaf water potential was measured using a pressure chamber. Five irrigation treatments were determined, consisting of: (a) a control, which was irrigated to full field capacity (FC) during the growing season; (b) two moderate water stress treatments (66% of FC) during vegetative and flowering stages; and (c) two severe water stress treatments during the vegetative and flowering stages (33% of FC). Because the severe treatment during the vegetative stage resulted in stopping of plant growth and adaptation, this treatment was omitted from our studies. For each treatment, measurements of plant height and fresh and dry weight were monitored by destructive harvests of eight randomly selected plants from the centre rows of each plot during the full flowering period. Plants were harvested at the soil surface, immediately weighed (fresh weight) and then oven-dried at 75 ℃ for 48 h and reweighed (dry weight). Also, for essential oil contents, the aerial parts of eight selected plants were collected and air-dried in the shade for 24 h and then were evaluated. All essential oil concentrations reported are based on the harvest of all aerial parts from whole plants.

The accumulation of oil increased significantly under severe water stress at the flowering stage, when the mean leaf water potential decreased from -0.5 to -1.6 MPa. This treatment affected the quantity of the essential oils more than moderate water stress during the vegetative and flowering stages. The main oil constituents are carvacrol and gamma-terpinene. The amount of carvacrol increased under moderate stress, while gamma-terpinene content decreased under moderate and severe water stress treatments.

The plants were cultivated in the Botanical Garden of the University of Agriculture, Plovdiv/Bulgaria on meadow-carbonate soil with neutral reaction (pH 7.1-7.2) and were harvested during the flowering period (July and September). The reserves of nitrogen, phosphorus and potassium in the soil (NPK) were: NH⁴⁺ 31.42 mg/kg; NO^3- 16.66 mg/kg; P₂O₅ 12.3 mg/100 g and K₂O 11.4 mg/100 g. Ammonium nitrogen and nitrate nitrogen were extracted from the soil with a 1% solution of KCI and were determined by consecutive distillation on a Parnas-Vagner apparatus. Phosphorus was determined by the Egner-Ream method and potassium was extracted with 2 n HCI and was determined by flame photometry. The plants were grown as seedlings and were planted in a two-row bed 50 × (20 + 20) cm in patches of 5 m². A scheme on the increase was used for the introduction of N, P and K fertilizers. The experiment was carried out as a randomized block modus - 15 variants in 4 replications (6 levels for N and 4 levels for P and K). Phosphorus (triple superphosphate - 50 % active substance) and potassium (potassium sulphate - 50 % active substance) were introduced only once before planting. Nitrogen (the ammonium nitrate - 33 % active substance) was introduced in three portions - during preparing of the soil, during the plants drafting (active vegetation) and at the full bloom.

The highest oil yield was obtained from leaves in July for N4P2K4 (0.63%) and the basic components were piperitenone (29.4%) and piperitone (13.5%). The mineral fertilization had no effect on the oil yield from the flowers. Regardless of the variant, it was found that the flower oils in July were rich in caryophyllene oxide (12.0-48.4%) and piperitenone (3.0-7.0%), while the oil composition in September was different.

Plant materials were collected during the flowering period in July 2002 from the Dumluca Mountain in the vicinity of Divrigi village of Sivas city at 1900 m altitude and Saksagan Gorge in Saimbeyli village of Adana city at 1900 m altitude.

The flower, stem and root oils of T. cadmeum ssp. orientale collected from the Adana location were characterized with alpha-thujone (25%, 5.2%), cis-linalool oxide (6.8%, 12.8%), trans-chrysanthenyl acetate (5.8%, 8.5%) for flower and stem oils, and beta-eudesmol (10.3%, 6.2%, 13.8%); in addition, stem oil contained 1,8-cineole (6.6%) and root oil contained hexadecanoic acid (6.0%), spathulenol (5.8%) and beta-muurolol (5.3%). The flower and stem oils of T. cadmeum ssp. orientale collected from the Sivas location were characterized with camphor (25.9%, 14.8%), borneol (15.4%, 25.8%) and alpha-thujone (7.8%, 5.5%); in addition, stem oil contained 1,8-cineole (7.4%) and root oil contained nonacosane (16.2%), spathulenol (6.8%) and hexadecanoic acid (5.8%).

Plant materials were collected from the following localities in north western Turkey. A = Trabzon: Caykara, Soganli dag on July 28, 1994; B = Bayburt: Caykara, Mohakambo yaylasi on July 25, 1994; C = Trabzon: Koprubasi, Vizara yaylasi on July 20, 1994.

One hundred and four compounds were identified representing 97.5-99.5% of the total components detected in thymol/carvacrol (50.14/10.67%), thymol/linalool (23.14/20.24%) and linalool/alpha-terpinyl acetate/geraniol (21.55/16.70/11.17%) rich oils.