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).

Fresh leaf samples of C. salignus were collected on the campus of University of Zululand, KwaDlangezwa and Empangeni (Both in KwaZulu-Natal Province) , South Africa.

1,8-Cineole (63.4%), alpha-pinene (17.8%) and E-(beta)-ocimene (6.7%) were the major constituents identified in the KwaDlangezwa sample (Sample A). The Empangeni sample (Sample B) contained only 1,8-cineole (85.4%) and alpha-pinene (6.2%) as the main compounds present in the oil.

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.

The leaves of C. sempervirens were collected in the region of central Dalmatia (Croatia) within 12 months (1999).

The oils produced in the autumn (September and October) were found to contain higher amounts of alpha-pinene (71.0% and 79.2%) than the oils produced from February to May (28.4-32.5%). The smallest amount of alpha-pinene (28.4%) was recorded in February, at the same time as the amount of cedrol, the quantitatively most important oxygenated compound, reached its maximum (12.9%).

The aerial parts of Ducrosia anethifolia (DC.) Boiss. were collected in the wild from Mehdi Abad (Kerman province, in southern Iran) at the flowering stage in June 2006. The material was dried at room temperature.

The 63 components of this interesting plant were identified in the oil of D. anethifolia, representing 94.0% of the oil. alpha-Pinene (11.6%), terpinolene(3.2%) and (z)-beta-ocimene (2.8%) were the main hydrocarbon components present in the oil, while decanal (54.0%), cis-chrysanthenyl acetate(3.2%) and decanoic acid (1.3%) were the major oxygen-containing constituents.

Fresh F.angulata were leaves gathered and air dried in May, 2004 and the seeds collected in October, 2004 from both habitats (Shahoo and Nevakoh Mountains), Kermanshah Province western Iran.

The oil yield from seed was 5-fold that from leaves (3.2%/100g compared to 0.63%/100g). Cis-ocimene was the major constituent of the seed oil from both regions (64.8% and 76.11%) and a prominent constituent (>20% of the total oil) of the leaf oils of both habitats. alpha-Pinene was the next main component (7-27%) of all 4 oils. Seed oils, with one major component (cis-ocimene), differed from the leaf oils, which were composed mostly of 3 components (alpha-pinene, cis-ocimene, & germacrene D). Distinctions between the oils of the two habitats were less marked than the leaf-oil/seed-oil differences; the cis-ocimene content was higher and alpha-pinene was less in both seedand leaf-oils of the Shahoo habitats than the Nevakoh ecotype; trans-verbenol was absent from the Shahoo leaves, but reached a content of 5.8% in Nevahoh leaf-oil. Further distinctions were found in the content/presence/absence of 20-30 minor components of the oils.

Whole leaves and inflorescences of two wild strawberry cultivars ('Rugia' and 'Baron von Solemacher') harvested in 2008 during the agrotechnical experiment performed by Department of Vegetable and Medicinal Plants, University of Life Sciences in Lublin, were used as a material for determinations. Samples were collected before noon at sunny and dry days at the beginning of wild strawberry's flowering stage. Material was dried up to 35 ℃ in shadow and air just after the harvest.

Depending on a cultivar, air-dry inflorescences from wild strawberry contain from 0.21% ('Baron von Solemacher' cv.) to 0.30% ('Rugia' cv.), whereas leaves contains from 0.46% ('Baron von Solemacher' cv.) to 0.62% ('Rugia' cv.) of essential oils. GC/MS analysis of essential oils achieved from studied materials revealed presence of 70 (including 59 identified) compounds in leaves of 'Rugia' cv. and 58 (including 50 identified) compounds in leaves of 'Baron von Solemacher' cv. Essential oils from inflorescences of 'Rugia' cv. contained 52 (including 47 identified), while 'Baron von Solemacher' cv. contained 54 (including 46 identified) compounds. The chromatographic analyses by GC-MS revealed that myrthenol, nonal, linalool and phthalide dibuthyl dominated in essential oils obtained from leaves, while myrthenol, citronelol, linalool and geraniol - from those of inflorescences. There were qualitative differences between oil components at both studied materials and differentiation between both cultivars, as well.

Aerial parts of H. altaicus Willd. (Novopokr.) plants were randomly collected from the wild at four different altitudes, as described below, during the 1999-2001 vegetation periods. All the collections of the plant samples were carried out during massive bud formation and the beginning of flowering. Sample # 1 (3.4 kg) was collected on July 14, 1999 from LAT: 53° 05′ LON: 85° 00′, 330 m, Altai Region, Troiszkii Raion, around the village of Taldinka, 4-5 km below the Bolshoi Rechke, facing southwestern Sopki, Tipchakovo-Heteropalusovo-Pavilnaya steppe. Sample # 2 (10.5 kg) was collected on July 28, 1999 from LAT: 51°, LON: 86° 40′, 600 m, Altai Republic, Ongudaiskii Raion, at the right side of the delta of Lake Ursup, surrounding Stepushka village, along the roadside. Sample # 3 (8.5 kg) was collected on July 30, 2000 from LAT: 51° 39′ LON:79° 59′, 120 m of Altaiskii Krai, Litovskii Raion, 2 km southwest of the Ustianka village, along the roadside. Sample # 4 (6.5 kg) was collected on August 2, 2001 at LAT 50° 11′ LON 87° 53′, 1550 m of Altai Republic, Kosh-Agachiskii Raion, 24 km away from Kurai village, towards North-Tchuiskoe mountain chain following the right side of lake Tete where there is a mixture of heavy weeds.

The oil obtained from 330 m had alpha-pinene (18.6%), myrcene (18.6%), beta-phellandrene (17.2%), (E)-beta-ocimene (12.9%) and germacrene D (11.9%), while samples from 600 m consisted of myrcene (26.4%), alpha-pinene (23.2%), beta-phellandrene (18.0%), (E)-beta-ocimene (9.9%), germacrene D (4.3%) and sabinene (4.2%). The oil from 120 m had -pinene (22.0%), beta-phellandrene (21.6%), myrcene (19.5%), trans-beta-ocimene (11.3%), germacrene D (7.2%) and limonene (4.5%) as major components. At 1550 m the major components were germacrene D (22.0%), myrcene (18.0%), beta-phellandrene (14.0%), alpha-pinene (11.3%) and (E)-beta-ocimene (9.2%).

H. pectinutu is an odoriferous plant and occurs as a natural weed on the Fiji Islands and in West Africa as a winter hardy bush. In India, it grows as an erect perrennial shrub in Assam, Bengal and Madras regions. Tlie leaves are ovate and the leaf margins range from crenate to serrate. The flowers are pale purple to yellow in cymose clusters, arranged unilaterally. The nutlets are small, oblong and black.

The major compounds present in the Indian oil were sabinene (27.8%), beta-pinene (6.7%), limonene (4.03%), alpha-terpinolene (6.0%), caryopliyllcne (17.2%), alpha-bergamotene (4.1%) and a C20H32-diterpene (5.8%). Other major hydrocarbons present were gamma-terpinene (1.4%), alpha-humulene (1.1%), beta-selinene (1.0%) and gamma-elemene (2.7%). The oil is rather poor in oxygenated terpenoids, the only major oxygen compounds detected were terpinen-4-ol(3.1%), spathulenol(1.1%), an unidentified sesquiterpene alcohol (1.4%) and trans-alpha-bergamotot (2.5%). The total oxygenated compounds constituted about 11% of the oil.

The leaves and stems of Ichthyothere terminalis were collected at Marapanim, PA (sample A) and Manaus, AM (sample B).

The chief constituent found in the leaf oil of sample of, I. terminalis collected at Marapanim (PA) was sabinene (18.0%). The leaf oil of I. terminalis collected at Manaus (AM) was dominated by alpha-pinene (19-8%), sabinene (14.8%) and limonene (35.8%), while the main components identified in the stem oil were alpha-pinene (13.9%) and limonene (20.0%).

The plant materials were collected for P1: 2900 m, Ait Akak, Oukaimden, Atlas Mts, Morocco, N. Achak, A. Romane and M. Mahroug, 3 trees, ns, 12/12/2003; P2, 2200 m, Plateau of Matat, Atlas Mts, N. Achak, A. Romane and M. Mahroug, 3 trees, ns, 18/03/2003; P3: 2000 m, Foret Islane, Oukaimden, Atlas Mts, N. Achak, A. Romane and M. Mahroug, 3 trees, ns,12/12/2003. A portion of the leaves from each of the three trees (per population) were air dried for 16 days at room temperature (ca. 22 &#8451) to produce the dried leaf samples.

The oil yields from fresh leaves showed on differences among geographical sources. Air dried leaves appeared to yield more oil at the highest elevation (1.03%, Ait Lkak, 2900 m) than lower sites (0.67%, Plateau of Matat, 2200 m; 0.57%, Foret Islane, 2000 m). The essential oils from each geographic site had very similar composition in fresh versus air dried leaves. The essential oils from provenance Ait Lkak and Plateau of Matat were very similar and characterized by a high sabinene content (21.2, 35.9%), in contrast to 10.% sabinene from the provenance Foret Islane. The oil from Foret Islane had a high delta-cadinene content with 12.7%, whereas Aik Akak and Plateau of Matat contained only 0.6 and 0.8%.

The aerial parts of M. camphoratum were collected at Manaus, Amazonas (type A) and Vigia, Para, (type B).

The plants were collected from two different localities in the Amazon Region and their oils were found to be remarkably different. One oil obtained from the sample collected at Manaus was characterized by a high content of terpinolene (30.3%), limonene (13.8%) and delta-3-carene (13.2%). The main constituents found in the other oil distilled from a sample collected at Vigia were camphor (15.0%), alpha-phellandrene (20.5%) and beta-caryophyllene (8.9%)

Myrtle (M. communis var. italica) aerial parts were collected monthly during 2006-2007 from Jbal Stara of Haouaria region in North Tunisia, belonging to a subhumid bioclimate.

In conclusion, high fluctuations were observed in the oil yields and composition of different parts of Myrtus communis var. italica during all the collecting periods. They could be explained by genetic and environmental factors. Moreover, significant differences were revealed in the main oil compounds. alpha-Pinene percentages showed the most remarkable changes among the different part oils. So, leaf oils contained more alpha-pinene than those of the fruits and stems during the myrtle vegetative cycle.

Experimental: Two hundred grams of healthy mature intact leaves were harvested from each of the taxa growing on their own rootstocks at the UC South Coast Research and Extension Center. flocc = P. americana var. floccosa from Mexico D-7; stey = P. americana var. steyermarkii from Mexico El Salvador 3-22-16; nubi = P. americana var. nubigena from Guatemala 45-C-1; mex = P. americena var. drymfolia from Tasco, Mexico; guat = P. americana var. guatemalensis cult. Nimlioh from Florida; bwl = P. ameticana var. americana cult. Trapp from Florida.

Analysis of oils showed the presence of over 90 components, of which 76 were identified. P. schiedeana oil was found to contain alpha-pinene (23.7%), beta-pinene (23.2%) and beta-caryophyllene as major components. The major constituents of P. americana var. floccosa and P. americana var. steyermarkii were alpha-pinene (10.9%, 7.6%), beta-pinene (20.6%, 10.4%), alpha-terpineol (9.6%, 7.9%), beta-caryophyllene (12.6%, 8.4%), viridiflorene (0.1%, 10.3%) and globulol (0.1%, 9.2%), respectively. The oils of P. americana var. nubigena and P. americana var. drymifolia contained alpha-terpineol (18.4%, 393%) and methylchavicol (12.4%, 40.2%), as major components, respectively. P. americana var. guatemalensis was found to be rich in beta-caryophyllene (38.3%), while the oils of P. americana var. americana and P. primatogena contained alpha-pinene (27.5%) and beta-pinene (40.9%), and alpha-pinene (24.6%), beta-caryophyllene (20.7%) and germacene D (10.1%).

The branches of pine were collected in July, 1996 in 15 different locations in Lithuania in the following regions: Western part (Silute, Jurbarkas, Kursiu Nerija), Eastern part (Salcininkai, Zarasai, Moletai), Southern part (Varena, Trakai, Radviliskis) and central part (Ukmerge, Jonava, Kaisiadorys). The branches in each location were collected from the trees in approximately 1 km radius.

More than 70 constituents were identified (64 positively and 10 tentatively) in the oils. alpha-Pinene (18.5-33.0%) and delta-3-carene (9.1-24.6%) were dominating constituents with the only one exception when the germacrene-4-ol content in one of the samples was 13.2%. The important bornyl acetate content varied from 0.5% to 3.0%. The main sesquiterpenes were beta-caryophyllene, germacrene D, bicyclogermacrene, delta-cadinene, gamma-cadinene, germacrene D-4-ol, cubenol (2.0-5.1%) and alpha-cadinol (1.9-7.7%).

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%).

The leaves of R. eriocalyx were harvested at random from two localities of the forest in the North and South ranges of Boutaleb in Algeria at different altitudes during the full flowering stage. Sample N3(Locality: Northern slope; Altitude (m): 850; Collection date: Mar 20,1993); Sample S3(Locality: Southern slope; Altitude (m): 850; Collection date: Mar 20,1993).

Concerning the alcohols, the highest amount of 1,8-cineole (11.4%) coincided with a very low amount of terpinen-4-ol(1.0%) in sample N3 as well as with a generally low concentration of hydrocarbons (apart from camphene and pinene) in all samples of R. eriocalyx.

Samples of R. officinalis were collected in April 1998 during the full flowering period (Ro-1a), between June and July 1998 during the fruiting period (Ro-1b) and in December 1998 during the hibernation period (Ro-1c) from Cazorla, Segura y Las Villas Natural Park (province of Jaen, Spain). The plant material consisted of ca. 10 twigs per plant (with blossoming tips or not, depending of the harvesting date) from 5-10 single plants. Ro-1a (Location: Las Chozuelas, Altitude (m): 1150, Harvesting date: April 21, 1998, Phenological stage: Flowering); Ro-1b (Location: Las Chozuelas, Altitude (m): 1150, Harvesting date: June 19, 1998, Phenological stage: Fruiting); Ro-1c (Location: Las Chozuelas, Altitude (m): 1150, Harvesting date: December 30, 1998, Phenological stage: Hibernation).

The highest oil yields (161.8%) were recorded during the fruiting period (summer). In general, minimum amounts of camphor and maximum amounts of alpha-pinene were observed in winter. The concentration of 1,8-cineole was almost constant throughout the year, though other oil constituent levels varied randomly with the plant life cycle

Sage plant material was collected from two different localities (altitudes 110 and 400 m) in central Herzegovina near Mostar and at four different stages of development: vegetative period (leaves and stalks, January 2003), prior to flowering (leaves and stalks, April 2003), in the course of flowering (flowering tops, leaves and stalks, May 2003) and after flowering (leaves and stalks, August 2003).

The highest oil yield of the plant was after flowering (August). The oil samples obtained prior to flowering (April) and in the course of flowering (May) yielded remarkably less than those after flowering (August) and in the vegetative period (January). An unexpected high oil yield of the plant in the vegetative period (January) is probably due to lower moisture content in this stage of development. The oil yields ranged from 0.29% to 0.64% (altitude 110 m) and 0.45% to 1.07% (altitude 400 m), which reveals that altitude also has significant influence on oil yields. The oils from plant materials gathered prior to flowering (April) and in the course of flowering (May) were found to contain significantly higher percentages of alpha-humulene, manool, viridiflorol and caryophyllene, while the oils produced after flowering (August) and in vegetative period (January) have had higher percentages of alpha-thujone and camphor. Although the altitude has had an obvious influence on oil yields, it did not have significant influence on the qualitative and quantitative composition of their constituents.

Satureja cuneifolia Ten. growing wild in Middle Anatolian provinces of Turkey were collected at various growth stages: a =from Konya, collected in June, before flowering; b = from Konya, collected in July, from flowering plants; c =from Konya, collected in August, full-bloom plants.

In the oils of S. cuneifolia, 38 compounds were identified, with thymol (43.6-65.5%), carvacrol (4.7-31.2%), gamma-terpinene (trace-13.7%) and p-cymene (trace-11.5%) being dominant.

Plant materials were collected from the following localities. A: Antalya: Alanya, Sapadere, Beldibi-Baskoy in July 1991 (ESSE 9562). B: Icel: Anamur, Kas yaylasi in July 1991 (ESSE 9192).

Thirty-nine components were characterized in each oil representing 85-90% of the total components detected with beta-pinene (34-35%) and alpha-pinene (24-25%) as major constituents.

The aerial parts (~35 cm) of each taxa growing wild in eight localities of Almeria province were collected in May 1996. All samples were collected at full flowering. Sideritis pusilla (Lange) Pau ssp. pusilla var. typica, Population/location (UTM): Los Matarines (30SWF7992); Sideritis pusilla ssp. pusilla var. carthaginensis Font Quer, Population/location (UTM): Rambla del Hacho (30SWF7178); Sideritis pusilla ssp. pusilla var. granatensis (Pau) Font Quer, Population/location (UTM): Gafarillos (30SWG8702); Sideritis pusilla ssp. almeriensis (Pau) Malagarriga var. typica, Population/location (UTM): Sierra de Gador, Cerro de los Lobos (30SWF3575); Sideritis pusilla ssp. almeriensis var. littoralis Font Quer, Population/location (UTM): Los Morales (30SWF6775); Sideritis pusilla ssp. almeriensis var. salina Font Quer, Population/location (UTM): Los Pedregales (30SWG7835); Sideritis pusilla ssp. flavovirens (Rouy) Malagarriga, Population/location (UTM): Velez Rubio, Cerro del Huezno (30SWG8965); Sideritis pusilla ssp. osteoxylla (Pau) Pallares, Population/location (UTM): Cabo de Gata, Cerro de S. Miguel (30SWF7165)

Monoterpene hydrocarbons, alcohols, sesquiterpenes and diterpenes were the main constituents in all samples. Among these, alpha-pinene (7.1-25.4%), sabinene (5.9-20.4%), fenchone (0.9-19.3%), limonene (1.2-7.4%) and 1,8-cineole (1.8-15.6%) were the major compounds. The results confirm that there are differences between varieties and subspecies, while cluster analysis revealed that the oil composition potentially has chemotaxonomical significance for this taxon.

Solanum lycopersicum L. seedlings were grown from commercial seeds (cv. ACE 55 VF). Seeds were surface sterilized by gently shaking them in a 1% NaClO solution for 5 min and rinsed successively 10 times for 5 min in sterile demineralized water. The seeds were pregerminated in seed trays containing autoclaved peat substrate in a climate-controlled chamber (16 h photoperiod at a light intensity of approximately 300 µmol m^-2 s^-1 photosynthetically active radiation, 23-25 ℃ and 60% Relative Humidity). Ninety-five percent of the seeds germinated at 5 seeds/pot, after one week all the seedlings were showing the apical bud and two cotyledons. Seedlings were then selected for uniformity (plant height and number of leaves) from a large population, and were individually transplanted to 1200 ml pots containing autoclaved soil:sand mix (1:2, v/v). Half of the seedlings received the mycorrhizal treatment as described below. Mycorrhizal colonization of germinated tomato seedlings was induced by transplanting the plants into pots containing autoclaved substrate mixed with inoculum. Mycorrhizal plants (AM): plants were inoculated with 20 ml of Endorize IV commercial inoculum containing Glomus mosseae, Glomus intraradices, Glomus sp., infective units not specified (Biorize, Dijon, France) . Plants were supplied weekly with 20 ml/pot of Long Ashton nutrient solution with half of the content of phosphorus .We attempted to obtain mycorrhizal plants (AM) with size and tissue nutrient content similar to those of non-mycorrhizal plants (NAM) by supplementing NAM plants with more phosphate, since AM symbiosis enhances P uptake and this may alter the plant response to drought . Moreover, the use of plants with similar size allows the detection of drought direct effects not mediated by plant size when working with plants in containers, since unequal plant size can be responsible of differences in soil water depletion and plant transpiration, and consequently plants can be exposed to unequal stress. Thus, not mycorrhizal plants were grown on the same autoclaved substrate, without inoculum material, and supplied weekly with 20 ml/pot of full-strength Long Ashton solution containing 41 ppm of P.All of the seedlings were maintained in a climate-controlled chamber (16 h photoperiod at a light intensity of approximately 370 µmol m^-2 s^-1 photosynthetically active radiation, 23-25 ℃ and 60% Relative Humidity). One month after inoculation, plants were transferred to 3 L pots filled with the sterile substrate and kept in the climate chamber described above. Plants were watered with tap water and fertilized as indicated above.To induce an almost natural, reversible drought stress, thus allowing the plant enough time to acclimate, irrigation was stopped 24 h before measurements were taken. These treatments resulted in moderate water stress (lower than -2 MPa). Two stems, each containing 5-6 mature leaves, and one apical stem were selected in each plant for jasmonic acid (JA) treatment. In the JA treatment, the abaxial and adaxial surfaces of six leaves from two different branches were sprayed until runoff with a solution of 0.5 mM of JA (Sigma-Aldrich, St. Louis, MO, USA). The solution was prepared by dissolving JA in acetone and them diluting this mixture with water to 1 mM. Approximately 1.5 ml of JA solution, corresponding to 0.157 mg of JA, were sprayed onto each single leaf. JA-treated leaves were isolated with a protective plastic that prevented the rest of the plant from being treated. The plastic was removed after the spray has dried. Treatments were coordinated so that all plants were tested approximately 14-15 h after JA application to avoid any diurnal effects.Two months after inoculation, gas exchange and VOCs measurements were performed.

Root colonization by AM fungi favoured the leaf production of essential isoprenoids rather than nonessential ones, especially under drought stress conditions or after JA application.

Solanum lycopersicum L. seedlings were grown from commercial seeds (cv. ACE 55 VF). Seeds were surface sterilized by gently shaking them in a 1% NaClO solution for 5 min and rinsed successively 10 times for 5 min in sterile demineralized water. The seeds were pregerminated in seed trays containing autoclaved peat substrate in a climate-controlled chamber (16 h photoperiod at a light intensity of approximately 300 µmol m^-2 s^-1 photosynthetically active radiation, 23-25 ℃ and 60% Relative Humidity). Ninety-five percent of the seeds germinated at 5 seeds/pot, after one week all the seedlings were showing the apical bud and two cotyledons. Seedlings were then selected for uniformity (plant height and number of leaves) from a large population, and were individually transplanted to 1200 ml pots containing autoclaved soil:sand mix (1:2, v/v). Half of the seedlings received the mycorrhizal treatment as described below. Mycorrhizal colonization of germinated tomato seedlings was induced by transplanting the plants into pots containing autoclaved substrate mixed with inoculum. Mycorrhizal plants (AM): plants were inoculated with 20 ml of Endorize IV commercial inoculum containing Glomus mosseae, Glomus intraradices, Glomus sp., infective units not specified (Biorize, Dijon, France) . Plants were supplied weekly with 20 ml/pot of Long Ashton nutrient solution with half of the content of phosphorus .We attempted to obtain mycorrhizal plants (AM) with size and tissue nutrient content similar to those of non-mycorrhizal plants (NAM) by supplementing NAM plants with more phosphate, since AM symbiosis enhances P uptake and this may alter the plant response to drought . Moreover, the use of plants with similar size allows the detection of drought direct effects not mediated by plant size when working with plants in containers, since unequal plant size can be responsible of differences in soil water depletion and plant transpiration, and consequently plants can be exposed to unequal stress. Thus, not mycorrhizal plants were grown on the same autoclaved substrate, without inoculum material, and supplied weekly with 20 ml/pot of full-strength Long Ashton solution containing 41 ppm of P.All of the seedlings were maintained in a climate-controlled chamber (16 h photoperiod at a light intensity of approximately 370 µmol m^-2 s^-1 photosynthetically active radiation, 23-25 ℃ and 60% Relative Humidity). One month after inoculation, plants were transferred to 3 L pots filled with the sterile substrate and kept in the climate chamber described above. Plants were watered with tap water and fertilized as indicated above.To induce an almost natural, reversible drought stress, thus allowing the plant enough time to acclimate, irrigation was stopped 24 h before measurements were taken. These treatments resulted in moderate water stress (lower than -2 MPa). Two stems, each containing 5-6 mature leaves, and one apical stem were selected in each plant for jasmonic acid (JA) treatment. In the JA treatment, the abaxial and adaxial surfaces of six leaves from two different branches were sprayed until runoff with a solution of 0.5 mM of JA (Sigma-Aldrich, St. Louis, MO, USA). The solution was prepared by dissolving JA in acetone and them diluting this mixture with water to 1 mM. Approximately 1.5 ml of JA solution, corresponding to 0.157 mg of JA, were sprayed onto each single leaf. JA-treated leaves were isolated with a protective plastic that prevented the rest of the plant from being treated. The plastic was removed after the spray has dried. Treatments were coordinated so that all plants were tested approximately 14-15 h after JA application to avoid any diurnal effects.Two months after inoculation, gas exchange and VOCs measurements were performed.

Root colonization by AM fungi favoured the leaf production of essential isoprenoids rather than nonessential ones, especially under drought stress conditions or after JA application.

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.

Plant material and isolation procedure: Aerial parts of the plant were collected from two regions, from Kazeroon in southern Iran and Shahr-e-kord in western Iran at the time of flowering in June 2002.

The main components of the oil of S. pilifera collected from Kazeroon, in southern Iran, were spathulenol (15.8%), cis-chrysanthenol (15.3%), beta-caryophyllene (8.4%) and cis-chrysanthenyl acetate (6.9%), while for the plant collected from Shahr-e-kord, in western Iran, they were cis-chrysanthenyl acetate (21.8%), linalool (18.9%), terpinen-4-ol (11.9%) and cis-chrysanthenol (9.2%).

Aerial parts of T. fontanesii were collected during June 2004, in full blossom, in the Province of Tlemcen in four locations: Sidi-snoussi, Remchi, Sebdou et Sebaa-chiouki and again, during June 2005, in the last location.

The yield of oil obtained from the aerial parts of Thymus fontanesii harvested in the Province of Tlemcen (Algeria), calculated on dry material basis,varied slightly from station to station: Sebaa-chiouki = 5.20%, Sebdou = 5.25%, Sidisnoussi = 5.32%, Remchi = 5.46%. The composition of the four samples was quite similar, carvacrol (66.7-69.5%) being by far the main component. Other constituents, present at appreciable contents, were p-cymene (6.1-9.1%), gamma-terpinene (6.0-9.6%), linalool (3.0-4.0%), alpha-pinene (2.5-3.0%), myrcene (1.2-1.5%), and alpha-terpinene (1.1-1.4%). Conversely, thymol accounted only for 0.6-0.7% of the composition. Moreover, a sample harvested at Sebaa-chiouki, in June 2005, produced on oil with the same composition (68.3% of carvacrol). Obviously, aerial parts of T. fontanesii from the province of Tlemcen produced an oil whose composition differed substantially from that of the oil obtained from the same species harvested in Setif province and Constantine area (Algeria), dominated by thymol (67.8% and 68.2%, respectively).

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.