جستجوی مقالات مرتبط با کلیدواژه « essential oil yield » در نشریات گروه « زیست شناسی »

One of the medicinal plants in resort areas of Mazandaran province is Phlomis olivieri which is widely used in pharmaceutical, food and cosmetics industries. This study was investigated the essential oil compounds of Phlomis olivieri aerial parts in Baladeh (Noor) and Kelardasht and also investigating the effect of soil physical and chemical properties on quantitiy and quality of essential oil. Eerial parts of plants were collected and essential oil was extracted with Clevenger device and compounds were identified with GC and GC/MS. Soil samples were randomly picked and were transfered to soil science laberatory to determine physical and chemical properties. The results showed that in Baladeh region, 27 compounds were identified which comprise 92.04 percent of total essential oil volume. At Kelardasht site, 26 compounds were identified which comprise 97.43 percent of total essential oil volume. The highest compounds in both regions were: Alpha- pinene, Beta-Caryophyllene, (E)-Beta-Farnesence, Germacrene- D, Germacrene– B and Beta-Eudesmol. Average essential oil efficiency in Baladeh and Kelardasht sites were 0.35 and 0.75, respectively which the highest essential oil amount was achieved in Kelardasht region. There was positive correlation between essential oil yield and saturation percentage and soil absorbable nitrogen, phosphorous and potassium explaining that with increasing these elements, essential oil yield was increased. Also, positive and significant correlation was observed between essential oil yield and organic carbon and matter percent at probability of 5 percent. Negative and significant correlation was found between essential oil efficiency and pH at probability of 1 percent which means that the lower essential oil with increment in this factor. Due to the Kelardasht has a higher yield of essential oil and also the percentage of essential oil compounds than Baladeh, the use of Phlomis olivieri is recommended in Kelardasht for cultivation and also for more production of these compounds.

In order to study foliar application of amino acids on morphophysiological properties and thyme essential oil under different irrigation regimes, an experiment was conducted as a split plot based on a randomized complete block design with three replications in the Research Farm of Tarbiat Modares University Faculty of Agriculture in the year 2020 crop season. Experimental factors were irrigation regimes at three levels including normal irrigation, moderate water stress, severe water stress (withholding irrigation until  25%, 45% and 65% of soil available water depletion in the root zone respectively and then irrigation up to field capacity from plant establishment to harvest time), were randomized to the main plot units and spraying at 6 kinds (aspartic acid, tyrosine, proline, commercial amino acids, distilled water and without spraying) were located in subplot units. The results showed that with reduction of irrigation to the level of severe water stress, plant height, fresh and dry weight of leaves, leaf area, total chlorophyll, percentage of essential oil decreased, and glycol peroxidase and proline showed a significant increase compared to optimal irrigation. Catalase activity also increased under moderate water stress and decreased under severe water stress. Foliar application of amino acids had a positive additive effect on the studied traits. The highest essential oil yield (about 11.20 kg/ha) was assigned to plants under commercial and proline amino acid foliar application under full irrigation conditions. Based on the general results of proline foliar application, increasing the concentration of osmolites such as proline under water stress conditions was able to help the plant withstand drought stress by helping to maintain osmotic pressure and compensate for part of the reduction in growth and dry weight. Therefore, consumption of this type of amino acid under stress conditions is recommended to reduce the effects of drought stress. Under non-stress conditions, foliar application of this type of amino acid had the greatest effect on plant growth and yield.

Dracocephalum kotschyi Boiss. it is one of the medicinal and aromatic plants that can be found in natural habitats in mountainous and high areas of the country. This plant is very popular because of its large amounts of essential oil and important medicinal properties. In this study, in order to investigate the effect of the habitat on the physiological traits, yield and essential oil content, random sampling of the flowering branches of the plant in the full flowering stage with three replications was done from its natural habitats located in the altitudes of Espidan, Akher Dagh and Arkan in North Khorasan province. The results showed that the plants grown in Espidan region with 15.76 g F.W and 3.24 g D.W are the highest, and the plants of Akher dagh region with 12.58 g F.W and 2.68 g D.W, are the lowest in fresh and dry weight. In terms of the content of flavonoid compounds and the percentage of essential oil yield, the highest amount of these compounds was obtained from 69.63 (mg Q/g D.W) and 1.52% from the plants of Arkan heights. Further, the results showed that 23 compounds were identified in the essential oil of plants of three habitats, and the compounds of cis-α-Bergamotene, limonene and ß-ocimene were the main common compounds in the essential oils of three regions. In connection with the antioxidant property, the plants of Arkan area showed a higher antioxidant capacity than other habitats in inhibiting DPPH free radicals with 50.89 μg/ml. In terms of anthocyanin content, extract of Arkan plants with 2.96 mg of cyanidin 3-glucoside/g was a greater source of anthocyanin, with a significant difference compared to other plants. General conclusion The plants grown in the altitudes of Arkan showed more content of anthocyanin, flavonoid compounds, antioxidant capacity and essential oil yield than other habitats, and it seems that the Arkan habitat has the most suitable conditions for the cultivation of this valuable medicinal plant.

In order to investigate the effects of salicylic acid and cycocel under drought stress conditions on agronomic and biochemical properties and essential oil of lemon balm, an experiment as a factorial split-plot in a randomized complete block design with three replications was carried out in northwest of Yasuj province during 2019 and 2020. Drought stress as the main factor included 35% (control), 70% and 90% field capacity, and the subplots included cycocel (0 and 1000 μM) and salicylic acid (0 and 1 μM). Results showed that foliar application of salicylic acid and cycocel had significant effect on grain yield, essential oil percentage, plant height, fresh and dry weight of shoot and fresh and dry weight of root and the amount of catalase, peroxidase and malondialdehyde enzymes. The highest yield belonged to irrigation treatment after application of 35% moisture along with foliar application with cyclocel and salicylic acid. Also, the most of essential oil yield belonged to irrigation treatment after consuming 70% moisture along with foliar application with cyclocel and salicylic acid. In general, the results showed that foliar application of salicylic acid and cyclocel caused drought resistance in lemon balm, and therefore it is recommended for areas similar to the climatic conditions of the study.

In order to investigate the effect of organic fertilizers including compost and manure on morphological, yield and qualitative characteristics of Rosa damascena Mill, an experiment was conducted in a randomized complete block design with 7 treatments in 3 replications in 2018-2019 in Sirjan city. The treatments were compost (20, 25 and 30 tons per hectare) and manure (10, 15 and 20 tons per hectare) along with control (without fertilizer application). Results showed that fertilizer in all investigated characteristics was significant. Mean comparison of data showed that 20 tons / hectare manure responded better regarding to canopy, height, leaf length and width, fresh and dry weight of flowers, number of flowers, phenol, chlorophyll, and antioxidant. As well, 30 tons / ha compost  showed  maximum in number of branches, leaves per plant, fresh and dry weight per plant  and essential oil yield. Also, cluster analysis showed that 20 and 30 tons / hectare manure and compost were put in the same group. As conclusion, 20 and 30 tons / hectare manure and compost, respectively, had the maximum effect on morphological and qualitative characteristics of Rosa damascena Mill seedlings.

Drought stress is as one of the most important limited factors that in agriculture systems can cause damage to growth, yield and secondary metabolites in medicinal and aromatic plants. A filed experiment to study on effect of irrigation frequencies, including 4, 6, and 8 every days on quantity and quality of the essential oil from the aerial parts of sage (Salvia officinalis L.) was done based on a randomized complete block design (RCBD) in three replications at the research field at Islamic Azad University of Shahrekord, southwestern Iran in 2016. The leaves of plant samples were harvested at early flowering stage and the essential oils were obtained by  hydro distillation by using the Clevenger-type apparatus d by GC/MS. Results indicated that irrigation frequencies levels had significant effects on essential oil yield and percentages of 1,8-cineole (as the main constituent in the oil), limonene and α–humulene. The highest yield oil and the maximum contents of 1,8-cineole (11.05%), limonene (2.67%) and α–humulene (1.32%) were obtained from treatment of eight every days of irrigation. Probably, it seems that increased irrigation intervals (mild drought stress) can be effective in quantitative and qualitative properties of essential oil from sage (Salvia officinalis L.).

In order to assess the genetic variation in Stachys accessions, an experiment was carried out in randomized block design with three replicates on 41 accessions including Ferydoonshahr (1), Damaneh (21), Gavkhoft (15), Semirom (4). According to analysis of variance significant differences were observed among all studied traits but not significant differences were observed among replications. Damaneh 20 had the highest amount of essential oil (3.37 %) and Damaneh 17 possessed the lowest essential oil content (0.092 %). According to factor analysis, the first factor explained 26 % of variation. Wet weight, plant height and number of floret showed the highest values in this factor. Number of leaves in main branch and number of leaves in lateral branch had the highest value in the second Eigen. Cluster analysis classified 41 accessions in five major groups and they revealed high differences in wet weight, dry weight, day to flowering, days to fruit set, number of floret and essential oil yield. Finally, it would be possible to cross the elite genotypes from different clusters and select the best ones in order to introduce new cultivars with appreciable agronomic traits and the highest essential oil yield.

In order to study the genetic variation and relationships among traits، an experiment on 15 genotypes of Dracocephalum moldavica L. under field conditions was carried out in a randomized complete design with 4 replications in Payam Noor University، Esfahan. Morphological charaters، including fresh and dry herb yield، plant height، stem diameter، number of auxiliary shoots، number of leaves/plant، 1000- grain weight، essential oil yield and essential oil content. Results of analysis of variance showed، significant differences for all studied traits (p< 0. 01) with the exception of essential oil content. High values of phenotypic and genotypic coefficients of variation were obtained for most traits، indicating high variability in the traits under study. Essential oil yield varied from 0. 49 (ml/pot) in genotype Khomeini Shahr to 0. 81 in genotype of Birjand. Essential oil yield had a significant high and positive correlation with fresh herb yield، number of auxiliary shoots، plant height، dry herb yield and essential oil content. Cluster analysis grouped the 15 genotypes within 3 groups. Genotypes in first group had higher essential oil yield، fresh herb yield، dry herb yield، plant height and number of auxiliary shoots. Our results indicate the presence of comparable genetic potentials in genotypes of Dracocephalum moldavica L. for cultivar development.