Artificial inoculation of fungal isolates: The most frequently isolated fungi from infected agarwood (e.g. Chaetomium globosum and Fusarium oxysporum) were inoculated to the healthy plants by artifi cial boring on to the plants. Inoculation was made with two different fungi alone and in their combination. Observations were made at an interval of 30 days after inoculation.

This investigation showed a marked difference in the oil compositions among the treatments with regards to their quality. Valerianol (3.0%) and tetradec-anioc acid (7.1%) contents were recorded higher in the oils of naturally infected plants than in that of healthy ones (0.1% and 6.9%, respectively). Pentadecenoic acid was totally absent in the oils of healthy, whereas it was found in a greater amount (6.8%) in the oil of naturally infected plants. In contrast, dodecanoic acid (3.1%), pentadecanoic acid (6.2%), hexadecanoic acid (31.5%) and octadecanoic acid (4.1%) were found in a higher amount in the oils of healthy plants, while the oils obtained from naturally infected plants contained lower amounts of these components (2.5%, 4.8%, 20.0% and 1.0%, respectively). The oils obtained from the inoculated plants showed almost similar distribution of the components with healthy plants.

Populations of A. annua cultivar 'Jeevanraksha' and accession Suraksha were grown in the experimental field plot of the Institute at New Delhi. The seeds were sown in January 2004, seedlings transplanted in late February 2004 and aerial parts (flowers, leaves and stems from the upper 0.5 m of crop canopy) sampled in late October 2004.

Ninety-seven compounds comprising 91.3% of the total oil of 'Jeevanraksha' were identified. Forty-three monoterpenes (56.6%), 32 sesquiterpenes (31.1%), and 2 diterpenes (0.2%) comprised bulk of the oil (87.9%). The oil was devoid of artemisia ketone and contained camphor (13.5%), 1,8-cineole (9.4%), trans-sabinol (7.1%), p-mentha-1(7), 5-dien-2-ol (6.3%), myrcene (4.7%), germacrene D (4.4%), (E)-beta-farnesene (3.9%), beta-caryophyllene (3.7%), dihydroartemisinic lactone (3.0%) and p-cymene (2.0%) as the major constituents. Eighty-six compounds representing 93.3% of the composition were identified in the Suraksha oil. This oil contained artemisia ketone (47%), 1,8-cineole (8.4%), camphor (5.9%) and alpha-pinene (5.2%) as the major components.

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 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.

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.

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.

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%).

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.