مجله تحقیقات گیاهان دارویی و معطر ایران
سال سی و هشتم شماره 1 (پیاپی 111، بهار 1401)

Thyme (Thymus vulgaris L.) is rich in phenolic monoterpenes such as thymol and carvacrol. Seed-borne fungi can reduce the quality and quantity of crop and also change the amount and type of secondary metabolites in plants by affecting seed health. The aim of this study was to isolate and identify the seed-borne fungi from thyme seed samples and to evaluate the effects of seeds infection on the production and expression of genes involved in the biosynthesis pathway of thymol and carvacrol compounds. To identify seed-borne fungi of thyme seed samples collected from fields of Alborz province, sampling was done according to the criteria of the International Seed Testing Association (ISTA). The amount of thymol and carvacrol compounds was measured using high performance liquid chromatography (HPLC) and the expression of TvTPS1, DXR, CYP178, and CYP180 genes was assayed by reverse transcription polymerase chain reaction (RT-PCR). Six Alternaria brassicicola isolates were identified based on morphological and molecular characteristics. Analysis of cell wall degrading enzymes activity revealed that cellulase and pectinase were more important than xylanase and chitinase on the pathogenicity and aggressiveness of isolates. Seeds infection by A. brassicicola significantly affected vigor and seed germination indices. The findings of this study showed that the pathogenicity and aggressiveness of A. brassicicola fungal isolates can change the expression level of different genes encoding thymol and carvacrol compounds in seedlings obtained from seed pretreatments with different isolates through different mechanisms including production of extracellular enzymes resulted in increasing (isolates Ab4 and Ab5) and/or decreasing (isolates Ab1, Ab6, Ab2, and Ab3) the production and accumulation of phenolic monoterpenes in thyme seedlings. This is the first report on the identification of seed-borne fungus A. brassicicola from thyme seed samples in Iran and also the role of seeds infection on the production and expression of genes involved in the thymol and carvacrol biosynthesis pathway.

To investigate the response of quantitative and qualitative yield of ajwain (Carum copticum L.) to the irrigation cut-off in different nutritional regimes, an experiment was conducted as split-plot in a randomized complete block design with four replications at the research farm of Sarvestan Agricultural Jihad Organization, Fars province in 2019. The factors consisted of irrigation as the main factor at two levels (optimal irrigation and irrigation cut-off at flowering stage) and nutritional regime as the sub-factor at six levels (control, mycorrhiza, 15 ton.ha-1 manure, 15 ton.ha-1 manure + mycorrhiza, 30 ton.ha-1 manure, and 30 ton.ha-1 manure + mycorrhiza). The irrigation cut-off treatment reduced the plant height, number of umbrellas per plant, number of seeds per umbrella, 1000-seed weight, seed yield, biological yield, essential oil percentage, and essential oil yield by 30.65, 37.25, 46.12, 43.40, 24.40, 41.78, 19.68, and 52.86%, respectively compared to the optimal irrigation. The use of manure and mycorrhiza significantly increased all the mentioned traits. Moreover, the interaction of irrigation and nutritional sources treatments significantly affected only the percentage and essential oil yield. The highest percentage (2.80%) and essential oil yield (15.02 kg.ha-1) was observed in the 30 ton.ha-1 manure + mycorrhiza and optimum irrigation treatment. The lowest essential oil percentage (1.60%) was obtained in the control and optimum irrigation treatment and the lowest essential oil yield (4.62 kg.ha-1) resulted from the control and irrigation cut-off treatment.

Olive (Olea europaea L.) is a valuable medicinal tree in addition to being used as a food. Olive leaf, as an organ containing active ingredients, is of great value in various industries. Use of olive leaves extract as a natural antioxidant is one of the most common applications of this plant. Oleuropein is the most important phenolic compound in olive species that plays an important role in health. Oleuropein and quercetin are used as effective compounds in anti-cancer, anti-virus, and anti-inflammatory drugs. To investigate the effects of vermicompost (0, 1, 2, 3, and 4 tons per hectare) application on morphological traits, leaf yield, and oleuropein, quercetin, macro and micro elements of the olive leaf extract under field conditions, an experiment was conducted in a randomized complete block design with three replications (nine shrubs in each replicate) at the Alborz Research Station, Research Institute of Forests and Rangelands in two years. Three-year-old shrubs were planted at a distance of 5 m on the row and 5 m between the rows at a depth of 50 cm. Vermicompost affected fresh and dry leaf yield per hectare and quercetin and oleuropein amounts of the leaves significantly (at the level of 1% probability) in both years. The highest dry leaf yield per hectare was obtained in the 4 tons of vermicompost treatment (55.573 kg in the first year and 63.047 kg in the second one). The amount of quercetin increased from 18.48 and 18.7 µg.mg-1 dry matter in the control treatment (in the first and second years, respectively) to 34.67 and 37.7 µg.mg-1 dry matter in the 4 tons vermicompost per hectare treatment (in the first and second years, respectively). Also, the use of 2 tons of vermicompost per hectare increased the leaf oleuropein in both years. Different vermicompost treatments increased the uptake of most macro and micro elements including phosphorus, calcium, magnesium, iron, manganese, zinc, and copper in both years. The results showed that the appropriate amounts of vermicompostcould be used to produce a plant with high quercetin and oleuropein.

Due to the valuable role of savory (Satureja spp.) in pharmaceutical and food industries, three separate factorial experiments were conducted in a completely randomized design with four replications in Islamic Azad University, Branch of Shahrekord in the 2021-2022 crop year to study the effects of NPK, butamisol, and humic acid fertilizers on the morphophysiological characteristics and essential oil of three savory species (S. bachtiarica Bunge, S. mutica Fisch. & C. A. Mey., and S. khuzistanica Jamzad) under drought stress conditions. Experimental treatments included non-use (A1) and use (A2) of NPK, non-use (B1) and use (B2) of humic acid, non-use (C1) and use (C2) of botamisol, and drought stress at three levels of field capacity (D1), and 50% (D2) and 75% (D3) moisture loss. The A2B2C2D1 treatment resulted in the highest plant height (57.5±1.1 cm), number of main branches (23.4±1.7), total chlorophyll (1.55±0.02 mg.g-1 FW), and essential oil content (1.94±0.03%) in S. bachtiarica. The highest proline (13.99±1.2 µg.g-1 FW) and lowest essential oil (0.79±0.02%) amounts was obtained in S. mutica in the A1B1C1D3 treatment. From the 11 essential oil compounds, monoterpenoids such as ρ-cymene and carvacrol in S. bachtiarica, carvacrol and ɣ-terpinene in S. khuzistanica, and ρ-cymene and thymol in S. mutica were identified as major essential oil constituents. Better nutrition and minimum stress with temperate climate of the region under study led to the introduction of S. bachtiarica as the best species.

The present study was aimed at investigating the ecological needs of endemic and medicinal species Pulicaria aucheri (Boiss.) Jaub. & Spach in Hormozgan province. Surveys were performed in three main habitats of the species including Bastak, Sirmand, and Geno. Analysis of habitat parameters in the mentioned areas showed that all measurement parameters except frequency were significantly different at 5% probability level. The mean canopy area, density, and frequency of this species were respectively 5.3%, 2611 plants per hectare, and 66%. The highest percentage of total canopy coverage, forage production per hectare, number of plants per hectare, litter percentage, percentage of canopy coverage, and plant height was observed in Sirmand region. The highest percentage of uncovered soil was measured in Bastak region and the highest percentage of stones and gravels was observed in Geno region. Analysis of regions soil parameters showed that all measurement parameters except soil acidity were significantly different at 5% probability level. The highest electrical conductivity, percentage of saturation, and soil silt was obtained in Bastak region. Sirmand region had the highest amount of lime and soil sand. Also, the highest percentage of organic carbon, nitrogen, and soil clay was observed in Geno region. The soil texture was loam and sandy-loam in Bastak region, sandy-loam in Sirmand region, and sandy-clay-loam in Geno region. The results of phenological studies showed that the peak flowering time (from early March to early April) is the best flowering shoots harvest time of this species for medicinal purposes. Due to the being endemic, having essential oil and antimicrobial effects, as well as severe grazing by livestock, it is necessary to pay more attention to this valuable species.

Satureja mutica Fisch. & C. A. Mey. is one of the native savory species of Iran that has received much attention due to its high essential oil content and phenolic compound of thymol. Determination the most suitable and best planting density as well as soil fertility is very important in increasing the quantitative and qualitative yield of medicinal plants. In this study, to investigate the effects of plant density and feeding with organic fertilizers on quantitative and qualitative yield of essential oils in Satureja mutica Fisch. & C. A. Mey. under rainfed conditions, an experiment was conducted as split plots in a randomized complete block design with 3 replications in the Research and Education Center of Agriculture and Natural Resources of Kermanshah province in 3 crop years (2018-2020). The main factor included 3 fertilizer treatments and the sub-factor was 3 densities (2.66, 4, and 8 plants per square meter) in rows with a distance of 50 cm and with 3 planting distances (25, 50, and 75 cm). Plant aerial parts were harvested at full flowering stage and their essential oil (EO) was extracted by hydrodistillation method. EO yield was calculated according to the plant dry weight and its chemical compounds were identified using GC and GC/MS. The results showed that percentage and EO chemical composition did not show any difference between the years. There was a significant difference between the fertilizer treatments for the percentage and EO yield and thymol, carvacrol, and other EO chemical compounds at the level of 1%. There was a significant difference between the planting densities only for EO yield. Thymol had a positive relationship with the treatments of enriched straw and then rotten cow manure and the highest amount (53.2%) was observed in the enriched straw treatment. Carvacrol with the highest amount of 9.2%, showed a positive relationship with the rotten cow manure treatment.

To investigate the effects of mycorrhizal fungi on growth characteristics, physiology, and essential oil yield of thyme (Thymus vulgaris L.) under lead (Pb) stress, a factorial experiment was conducted in a completely randomized design with three replications in the research greenhouse of University of Mohaghegh Ardabili (UMA) in 2018. Experimental treatments included different levels of Pb heavy metal (0, 200, and 400 ppm) and inoculation with mycorrhizal fungi (without inoculation, inoculation with Funneliformis mosseae, and Claroideoglomus etunicatum). The results showed that in comparison with the control, with increasing Pb concentration in the soil, plant height (40.56%), number of leaves (36.09%), stem dry weight (43.50%), essential oil percentage (40%), and cell membrane stability (16.14%) were significantly decreased, while proline content (51.72%) and catalase activity (45%) of the leaves increased. Inoculation of thyme with the mycorrhizal fungi was effective in increasing the vegetative indices in presence of Pb heavy metal so that both G. mosseae and G. etunicatum increased the number of leaves by 66.20 and 9.55% compared to the control, respectively. Also, inoculation with G. mosseae under severe Pb stress conditions (400 ppm) increased leaf proline content (11.49%), peroxidase enzyme activity (8.8%), chlorophyll b (21%), total chlorophyll (70.43%), carotenoids (19.6%), and essential oil percentage (55%) compared to the control. Overall, both mycorrhizal fungi were effective on alleviation of Pb toxicity effects and F. mosseae had better performance, especially in terms of morphological traits and essential oil yield. Due to the negative effects of heavy elements on human health, the recommendations to use mycorrhizal fungi to reduce the absorption of heavy metals in plants should be done with more consideration of all aspects including the plant and fungus species type and rate and pollution type.

This experiment was conducted as split-plot in a randomized complete block design with three replications at the research farm of University of Gonabad in the 2017-18 crop year. The main plot included control, chemical fertilizer (100, 120, and 150 kg.ha-1 urea, triple superphosphate, and potassium sulphate, respectively), and vermicompost (10 t.ha-1) and sub-plot consisted of garlic (Allium sativum L.) and fenugreek (Trigonella foenum-graceum L.) intercropping in 25:75, 50:50, 75:25, and 100:100 proportions and sole cropping of two crops. The results showed that the highest number and bulblet length was obtained in the chemical fertilizer treatment, however there was no significant difference between this treatment and vermicompost. While, the vermicompost treatment resulted in the highest bulblet diameter. The highest bulblet number was obtained in the 50:50 intercropping treatment and the highest length and bulblet diameter was obtained in the 25:75 one. The highest biological yield and bulb yield (3867 and 2293 kg.ha-1) was obtained in the sole cropping of garlic and chemical fertilizer treatment. The highest garlic essential oil was obtained in the vermicompost (2.33%) and 50:50 intercropping (2.36%) treatments. The plant height and number of pods per plant in fenugreek had the highest increase (30 and 21%, respectively) in the chemical nutrition treatment. Also, the highest number of pods per plant was obtained in the 25:75 intercropping treatment. The highest forage and seed yield of fenugreek (2057 and 682 kg.ha-1, respectively) was observed in the sole cropping and chemical fertilizer treatment. The biological yield was higher in the chemical (2800 kg.ha-1) and organic (2733 kg.ha-1) fertilizer treatments under sole cropping. The highest essential oil of fenugreek seeds was observed in the chemical fertilizer (1.16%) and 75:25 intercropping (1.12%) treatments. The intercropping patterns recorded the land equivalent ratios above 1 and the best situation was obtained from 100:100 intercropping. Garlic was superior to fenugreek in the intercropping treatments except for 100:100 pattern. The intercropping advantage was greater than 1 except for the 100:100 treatment and the highest economic advantage was obtained in the 25:75 pattern and organic fertilizer treatment.

Microbial contamination is one of the main challenges and influential factors in the response of explants under in vitro cultures, especially in woody plants where the explants are prepared from natural habitats. In the present study, to investigate the effects of benomyl on microbial contamination and growth of Vaccinium arctostaphylos L. node explants, MS containing different concentrations of benomyl (0-2000 mg.L-1) was used. Furthermore, to investigate the interaction of benomyl, basal medium, and hormonal composition on the growth response of explants, different basal media (MS, AN, and WPM) containing IBA (0.1 mg.L-1), cytokinin (Zeatin, BAP, and TDZ, each at concentrations of 0, 0.5, 1, and 2 mg.L-1), and benomyl (0 and 150 mg.L-1) were studied. The results showed that benomyl in MS medium had no significant effect on the explants contamination, but use of lower benomyl concentrations (400 mg.L-1 or less) could provide better growth conditions. Interaction of treatments significantly affected the percentage of survival and explants foliation. MS contained benomyl showed higher percentage of survival and foliation than MS without benomyl, but in AN and WPM media, the percentage of survival and foliation were significantly decreased in the presence of benomyl. Furthermore, in AN and WPM media contained cytokinin, the presence of benomyl significantly reduced the foliation percentage, while in MS medium, the effect of benomyl was different depending on the concentration and cytokinin type.

The thornless Black berry (Rubus occidentalis) contains components such as elagic acid, anthocyanin, campherol and salicylic acid. So, it has high antioxidant activity that can inactivate the free radicals and prevent many diseases, such as cancer. Optimization of tissue culture methods for mass production and gene transfer is very important for blackberry. The present study was aimed at determining the effects of different plant growth regulators concentrations on regeneration and rooting and the effects of different concentrations of sucrose on rooting of thornless black berry (Rubus occidentalis L.) under in vitro conditions. Interaction of BA (0.2, 0.5, 1, 1.5, and 2 mg.L-1) and IBA (0 and 0.1 mg.L-1) was investigated on lateral bud explants regeneration. In the rooting stage, the effects of IBA and NAA each at four levels of 0.2, 0.5, 0.75, and 1 mg.L-1 as well as sucrose at four levels of 1, 1.5, 3, and 4.5% were studied. BA (1 and 1.5 mg.L-1) + IBA (0.1 mg.L-1) was the best regeneration treatment (regeneration: 100%, number of shoots: 4.6, and shoot length: 1.30 cm). The results indicated that the best rooting medium contained NAA (0.75 mg.L-1) and sucrose 3 and 4.5% (rooting: 100%, number of roots: 7.5, and root length: 2.88 cm).

Dragonhead with the scientific name of Dracocephalum moldavica L., is an annual medicinal and aromatic herbaceous plant from Lamiaceae family. In this research, D. moldavica seed oil, aqueous, and ethanol extracts were prepared and quantity and quality of fatty acids, phytosterols amount, phenolic and flavonoid compounds contents, and DPPH radicals scavenging activity were measured. The seed oil was extracted by cold press method. The results showed that the highest amount of palmitic and stearic acids (9.4 and 3.55%, respectively) was obtained in the ethanol extract. While, the highest amount of oleic (9.7%), linoleic (19.53%), and α-linolenic (59.01%) acids were found in the oil. The ethanol extract exhibited the highest amount of total phytosterol (833.86 mg.100 g-1 DW), γ-tocopherol (38.72 mg.100 g-1 DW), and total tocopherol (39.21 mg.100 g-1 DW). The highest total phenolic (17.4 mg GAE.g-1 DW) and flavonoid (112.12 mg QE.g-1 DW) contents were found in the ethanol extract of seeds and lowest of them (near to zero) was found in the seed oil. Also, the ethanol extract showed the highest DPPH radicals scavenging activity. Overall, ethanol is recommended as the best solvent for extracting dragonhead seed extract to maintain more qualitative properties.