Agriculture and horticulture
Mohammad Haghaninia; abdollah javanmard; Zahra Ghorbani; mohammad reza morshedloo; Karim Kakaei
Abstract
Background and Objective: In contemporary times, the importance of medicinal plants and their identification in advancing national, regional, and global objectives, such as achieving health, pharmaceutical self-sufficiency, fostering employment, and promoting economic development, ...
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Background and Objective: In contemporary times, the importance of medicinal plants and their identification in advancing national, regional, and global objectives, such as achieving health, pharmaceutical self-sufficiency, fostering employment, and promoting economic development, is indisputable. Mentha suaveolens × Mentha piperita, commonly referred to as grapefruit mint, is recognized as a valuable medicinal plant within the Lamiaceae family. Drought stands out as a major limiting factor for global plant growth, constituting the most prevalent environmental stressor that disrupts the balance between reactive oxygen species and antioxidant defense mechanisms, thereby inducing oxidative stress. Nanotechnology emerges as a modern approach with notable potential to enhance plant resilience against drought stress. Among various nanomaterials, carbon quantum dots, discovered in 2004, possess distinctive characteristics, including dimensions below 10 nanometers, reduced toxicity, and superior biocompatibility compared to metal-based alternatives, owing to their carbonaceous structure. Due to these unique attributes, carbon quantum dots have attracted significant research interest in recent years. Therefore, this study aimed to evaluate the effects of carbon quantum dots on the growth, yield, and essential oil composition of grapefruit mint (Mentha suaveolens × piperita) under drought stress conditions.Methodology: This research was conducted as a factorial experiment in a completely randomized design with four replications in pots during the spring and summer of 2023 at the research greenhouse of Maragheh University, East Azerbaijan, Iran. The first factor was irrigation at 90% of field capacity (FC) as control (normal irrigation), irrigation at 70% FC (moderate stress), and irrigation at 50% FC (severe stress). The second factor consisted of different levels of carbon quantum dots (0, 5, 10, 15, and 20 parts per million). Data collected from sampling were analyzed using SAS statistical software, and means were compared using the least significant difference (LSD) test at the 5% level.Results: Analysis of variance indicated that the effects of different irrigation regimes, fertilizer treatments, and their interaction on all measured traits were significant. The findings revealed that the application of 15 ppm carbon quantum dots under normal irrigation increased fresh weight, dry weight, chlorophyll a, and chlorophyll b contents by 110%, 86%, 184%, and 163%, respectively, compared to no CQD application under severe drought stress. Under moderate stress, the use of 15 ppm carbon quantum dots increased essential oil content by 135% and essential oil yield by 298% compared to severe stress without CQD. Furthermore, the highest linalyl acetate content was obtained with 15 ppm carbon quantum dots under 50% FC, showing a 50.1% increase compared to the control treatment. Similarly, the highest linalool content was recorded under normal irrigation with 10 ppm carbon quantum dots, representing a 67.4% increase compared to no CQD application under 50% FC. Moreover, under normal irrigation, 15 ppm carbon quantum dots reduced malondialdehyde and hydrogen peroxide contents by 51% and 58%, respectively, compared to no CQD application under severe stress. Additionally, under mild stress, 15 ppm carbon quantum dots enhanced the activity of superoxide dismutase, guaiacol peroxidase, and ascorbate peroxidase enzymes by 123%, 111%, and 72%, respectively, compared to no fertilizer application under normal conditions.Conclusion: The results indicate that applying 15 ppm carbon quantum dots can promote growth by modulating secondary metabolites and strengthening defense mechanisms through the activation of antioxidant enzymes and increasing the accumulation of osmolytes such as proline and total soluble sugars, thereby reducing malondialdehyde and hydrogen peroxide levels. This enhancement in grapefruit mint plants contributes to improved drought resilience, ultimately enhancing both the quantity and quality of the essential oil.
Agriculture and horticulture
niloufar Rezaei; Fatemeh Sefidkon; hassan ali naghdibadi
Abstract
Background and Objective: The cultivation of medicinal plants, including savory (Satureja), is increasing worldwide. Savory, containing thymol and carvacrol in its essential oil, holds significant importance. This study aims to investigate the effects of planting density and soil fertility on the physiological ...
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Background and Objective: The cultivation of medicinal plants, including savory (Satureja), is increasing worldwide. Savory, containing thymol and carvacrol in its essential oil, holds significant importance. This study aims to investigate the effects of planting density and soil fertility on the physiological traits and antioxidant enzyme activities of savory under rainfed conditions. Considering the importance of these factors in enhancing plant resistance to stress, this research was conducted to determine the optimal planting density and soil fertility for boosting antioxidant activities and promoting the sustainable development of savory.Methodology: This study was conducted as a field experiment at the Hamand Absard Research Station in Damavand during the 2017–2018 and 2018–2019 growing seasons. The experiment was arranged in a split-plot design within a randomized complete block design (RCBD) with two factors. The main factor consisted of three fertilizer levels: (1) control (no fertilizer), (2) decomposed cattle manure (30 tons per hectare), and (3) straw enriched with ammonium sulfate (10 tons per hectare). The sub-factor included three planting densities: 2.67, 4, and 8 plants per square meter. Planting was performed using standard savory seeds. Land preparation involved plowing, disking, and leveling. Fertilizers were applied according to the treatments before planting. Irrigation was limited to rainfed conditions only. Leaf samples were collected at the full flowering stage. The measured physiological traits included relative leaf water content, total chlorophyll, proline content, electrolyte leakage, ion leakage, malondialdehyde content, and antioxidant enzyme activities (catalase, peroxidase, and superoxide dismutase). Samples were analyzed in the laboratory after harvest to evaluate the effects of treatments on the studied parameters. Data was analyzed using SAS software, and mean comparisons were performed using Duncan’s multiple range test at a 5% significance level.Results: This study demonstrated that planting density and organic fertilizer treatments significantly influenced the physiological traits and antioxidant defense responses of Satureja spicigera under rainfed conditions. The highest relative water content (87.67%) and the lowest electrolyte leakage (47.19%) were recorded in the treatment with cow manure and a low planting density of 2.67 plants per square meter, indicating improved water status and membrane stability. In contrast, increasing planting density reduced chlorophyll content and relative water content, while levels of proline, electrolyte leakage (ELI), and malondialdehyde (MDA) increased, reflecting greater stress intensity under high-density conditions. The application of cow manure and ammonium sulfate-enriched straw improved physiological performance and significantly reduced oxidative stress markers. These treatments promoted better osmotic regulation and membrane protection, contributing to greater stress tolerance. Interestingly, the highest activities of antioxidant enzymes, catalase, peroxidase, and superoxide dismutase were observed in the unfertilized control under high-density planting. This suggests that the plant naturally boosts its enzymatic antioxidant defenses under more stressful conditions, particularly when nutrients are limited. In conclusion, the results highlight that integrating organic fertilization with optimal planting density can enhance drought resilience by maintaining physiological stability and reducing oxidative damage. These practices not only support the sustainable cultivation of Satureja spicigera in water-limited environments but also improve the plant’s overall functional and medicinal quality.Conclusion: The results of this study show that savory (Satureja spicigera) has a good ability to grow and develop under rainfed conditions and demonstrates significant capacity to enhance its antioxidant activity. The combined use of organic fertilizers, especially cow manure, along with an appropriate planting density, is practical in improving physiological traits, increasing resistance to environmental stresses, and strengthening the plant’s enzymatic defense system. Implementing these findings can be valuable in enhancing productivity, ecological sustainability, and food security in areas with limited water resources.
Agriculture and horticulture
Mostafa Alinaghizadeh; Mohammad Azimi Gandomani
Abstract
Background and Objectives: Medicinal plant Plantago ovata is effective in treating gastrointestinal disorders and improving intestinal function due to its bioactive compounds, such as mucilage. Given the importance of psyllium as a valuable medicinal plant and the water resource limitations ...
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Background and Objectives: Medicinal plant Plantago ovata is effective in treating gastrointestinal disorders and improving intestinal function due to its bioactive compounds, such as mucilage. Given the importance of psyllium as a valuable medicinal plant and the water resource limitations in many regions, this study aimed to investigate the effect of sowing date on the growth and yield characteristics of psyllium under different irrigation regimes in the climatic conditions of Rafsanjan, Iran.Methodology: This experiment was conducted during the 2022–2023 growing season in Rafsanjan, Iran, at a farm located at 30°24′N latitude, 55°59′E longitude, with an elevation of 1467 meters above sea level. The area has an annual average rainfall of 120 mm and maximum and minimum temperatures of 43°C and -5°C, respectively. The experiment was laid out in a strip-plot design based on a randomized complete block design (RCBD) with three replications. Irrigation treatments, applied in the horizontal strips, included four levels: 40%, 60%, 80%, and 100% of the crop water requirement. Sowing dates (March 10, 2023, March 25, 2023, April 10, 2023, and April 25, 2023) were assigned to vertical strips. Irrigation treatments were initiated after complete seedling establishment (3–4 leaf stage) and continued until physiological maturity. The irrigation water requirement was calculated using AGWAT software, with water volumes of 1430, 1144, 858, and 572 cubic meters per irrigation for 100%, 80%, 60%, and 40% water requirement levels, respectively. Data analysis was performed using SAS 9.4 software, and means were compared using Duncan's test at the 5% probability level.Results: The results showed that the highest plant height (24.1 cm), number of tillers (6), spike length (14.3 cm), and number of spikes per plant (27.7) were achieved under the 100% water requirement treatment and the March 25 sowing date. Additionally, the highest number of seeds per plant (1245), seed yield (1876 kg. ha-1), and biological yield (5357 kg. ha-1) were observed under the same treatment. The highest harvest index (35.9%) was recorded with the 100% irrigation treatment and the March 10 sowing date. Furthermore, the maximum thousand-seed weight was obtained under the 80% water requirement (1.94 g) and the March 25 sowing date (1.88 g). Moreover, the highest mucilage content was reported under the 100% water requirement (23.9%) and the March 10 sowing date (22.4%).Conclusion: Overall, the findings demonstrated that sowing date and irrigation level significantly affect the growth and yield characteristics of psyllium. Delayed sowing and reduced irrigation levels led to significant declines in plant height, yield components, seed yield, biological yield, and harvest index. Therefore, selecting an optimal sowing date and ensuring adequate water supply can improve the performance of this medicinal plant.
Agriculture and horticulture
Nasrin Biyabani; Vahid Abdossi; Marziyeh Ghanbari Jahromi
Abstract
Background and objectives: Salinity stress is one of the most significant abiotic stresses that impede agricultural production. It is often accompanied by oxidative stress due to the generation of reactive oxygen species (ROS). Mitigating the effects of environmental stress on plants through the use ...
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Background and objectives: Salinity stress is one of the most significant abiotic stresses that impede agricultural production. It is often accompanied by oxidative stress due to the generation of reactive oxygen species (ROS). Mitigating the effects of environmental stress on plants through the use of growth-promoting compounds is of particular importance. In this context, silicon sources, such as potassium silicate, play a critical role in modulating salinity stress in plants. By enhancing plant resistance to salt stress, potassium silicate can contribute to improved growth and performance in areas with saline soils. These compounds promote cellular ion balance under adverse conditions and improve water uptake and retention in plants, thereby reducing ion leakage and the detrimental effects of salinity stress.Methodology: The present study aimed to investigate the effect of potassium silicate on the growth and physiological and biochemical characteristics of goldenrod in a factorial design based on a completely randomized design with the factor of salinity stress at three levels (0, 60, and 120 mM) and foliar application of potassium silicate at three levels (0, 50, and 100 mg/l) under greenhouse conditions. Foliar application was carried out three times at 15-day intervals. The first foliar application was performed at the 4-leaf stage. After the second foliar application, salinity stress was induced by applying 200 milliliters of sodium chloride solution to each pot for 40 days. To prevent salt accumulation in the pots, all pots were rinsed with non-saline water after every 4 irrigations with saline water. The morphological variables investigated include wet and dry weight of shoots and roots and plant height and other traits including plant pigments (chlorophyll a, b and total), relative leaf water content, ion leakage rate, proline, sodium and potassium absorption rate of roots and it was the aerial parts that were measured in the middle of the golden grass flowering period.Results: Salinity stress caused yield reduction, and potassium silicate moderated the negative effects of salinity stress and improved plant growth conditions. The evaluations showed that the salinity of 120 mM caused a decrease in the fresh weight of shoot (28%), dry weight of shoot (29%), fresh weight of root (38%), dry weight of root (37%), total chlorophyll (40%), the relative content of leaf water (17%), root potassium (14%) and leaf potassium (16%) and increased ion leakage (23%), proline (13%), root sodium (256%), sodium leaves (325%). Potassium silicate, especially 100 mg/l, moderated salinity stress by increasing plant weight, chlorophyll, leaf water, and potassium content in leaves and roots and reducing sodium accumulation in leaves and roots and ion leakage.Conclusion: The general results of the research showed that increasing the intensity of salinity stress had negative effects on the growth and functional characteristics of golden grass and potassium silicate in the volume of 50 to 100 mM caused the adjustment of salinity stress by increasing the quantitative and qualitative performance (biochemical and phytochemical) of golden grass. Therefore, to cultivate the golden grass plant, it should be noted that the water or soil used does not contain salts such as sodium and chlorine, or soil conditioners or growth stimulants should be used for the production and cultivation of this plant.
Agriculture and horticulture
leili safaei; Fatemeh Sefidkon; saeed- davazdahemami-; Davood Aminazarm
Abstract
Background and objectives: Satureja khuzistanica Jamzad is a medicinal plant belonging to the Lamiaceae family and is one of Iran’s exclusive species. Due to its high essential oil content and significant amounts of carvacrol, it is particularly important in the cosmetic, health, and pharmaceutical ...
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Background and objectives: Satureja khuzistanica Jamzad is a medicinal plant belonging to the Lamiaceae family and is one of Iran’s exclusive species. Due to its high essential oil content and significant amounts of carvacrol, it is particularly important in the cosmetic, health, and pharmaceutical industries. This study aimed to evaluate the plant’s adaptation to the climatic conditions of Isfahan province and enhance its quantitative and qualitative performance by identifying the most suitable fertilization method.Methodology: This project was conducted at Fozveh Station of the Agricultural and Natural Resources Research Center of Isfahan from 2017 to 2020 under irrigation conditions, using a randomized complete block design (RCBD) with eight fertilizer treatments. The treatments included different levels of chemical fertilizers (N50P25K25), organic fertilizers (30 and 60 tons/ha of cow manure, and 5 tons/ha of vermicompost), and combinations of chemical and organic fertilizers (N50P25K25 + 30 tons/ha cow manure, N50P25K25 + 60 tons/ha cow manure, and N50P25K25 + 5 tons/ha vermicompost). These treatments were compared with a control group, and the experiment was replicated three times. Seeds and seedlings were sourced from the Isfahan Agricultural and Natural Resources Research Center and the Research Institute of Forests and Rangelands. Cultivation was performed indirectly through seedlings, which were first grown in greenhouse conditions using cultivation trays. In April 2017, after favorable weather conditions were established, the seedlings were transplanted to the field. Drip irrigation was applied immediately after transplanting, with watering scheduled twice a week in the early growth stages and once a week after plant establishment. The aerial parts of the plants were harvested at 50% flowering, cut 5 cm above the soil surface, and dried in the shade. Essential oil extraction was performed annually using water distillation (Clevenger apparatus). The essential oil percentage was measured, its composition was analyzed using gas chromatography (GC), and qualitative assessment was conducted through gas chromatography-mass spectrometry (GC-MS).Results: According to the results, the maximum essential oil percentage and oil yield in S. khuzistanica were 3.7% (in the third year) and 132.6 kg/ha (in the second year), respectively. Across the experimental years, the highest oil yield was obtained in the combined treatment of 50 kg/ha nitrogen, 25 kg/ha phosphorus, and 25 kg/ha potassium, plus 5 tons/ha vermicompost, in the third year. Throughout the study, 14 compounds were identified in S. khuzistanica essential oil, with carvacrol being the predominant component. The concentration of carvacrol ranged from 86.4% to 95.3%.Conclusion: According to the results, the qualitative yield of essential oil in S. khuzistanica was less affected by soil fertility treatments, while the quantitative yield showed a significant increase, which indirectly enhanced the qualitative yield. Ultimately, the study concluded that the intermediate fertilization method was the most effective treatment for improving quantitative yield and promoting sustainable agriculture. The high carvacrol content in this species adds to its economic value. Given its diverse biological properties, including antiseptic, anti-inflammatory, analgesic, antibacterial, antifungal, and antioxidant activities, S. khuzistanica is recommended for applications where this valuable compound is required.
Agriculture and horticulture
Fatemeh Borna; Mostafa Rahmati-Joneidabad; Sadegh Abdrahmani
Abstract
Background and objectives: The use of chemical fertilizers to produce high-yield crops in the shortest possible time has raised public concerns regarding food sustainability, safety, and security. Consequently, alternatives such as biofertilizers are necessary to ensure food safety and sustainability. ...
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Background and objectives: The use of chemical fertilizers to produce high-yield crops in the shortest possible time has raised public concerns regarding food sustainability, safety, and security. Consequently, alternatives such as biofertilizers are necessary to ensure food safety and sustainability. Biofertilizers are essential tools in sustainable agriculture and can enhance plant resilience to environmental stresses. Their application in the cultivation of medicinal plants, whose primary purpose is to promote public health, is steadily increasing. The medicinal plant Dracocephalum moldavica L., commonly known as dragonhead and a member of the mint family, contains essential oils throughout its tissues. In traditional medicine, it is used to treat mental fatigue, migraines, cardiovascular ailments, congestion, headaches, stomach pain, liver disorders, and as a sedative. This study aims to investigate the effects of biofertilizers on the growth and essential oil properties of dragonheads under the climatic conditions of Khuzestan.Methodology: The influence of biofertilizers on the growth, yield, and both the quantity and quality of essential oil in dragonhead was assessed using a randomized complete block design with seven treatments and three replications. The study was conducted at the Department of Horticultural Science, Khuzestan Agricultural Sciences and Natural Resources University, in 2022. Following soil analysis and land preparation, seedlings were transplanted to the main field in March. All agronomic practices, including irrigation and weed control, were uniformly applied across treatments. The treatments consisted of a control (no fertilizer - C), inoculation with bio-potassium (K), bio-nitrogen (N), bio-phosphate (P), a combination of bio-nitrogen and bio-phosphate (NP), bio-nitrogen and bio-potassium (NK), and a combination of all three (NPK). The aerial parts of the dragonhead were harvested at the flowering stage. Evaluated traits included plant height, number of inflorescences, length of the main inflorescence, fresh weight, dry weight, essential oil content, dry weight yield, and essential oil yield. Essential oils were extracted through water distillation using a Clevenger apparatus, and their components were identified via gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). Data were analyzed using SAS statistical software (version 9.1), and means were compared using Duncan’s multiple range test at a 5% significance level. Charts were created using EXCEL software.Results: Analysis of variance indicated that biofertilizers significantly influenced all measured traits in dragonhead. Mean comparison results showed that the highest plant height (90.08 cm) was achieved with the P treatment. The NPK treatment produced the highest number of inflorescences (11.91), length of the main inflorescence (31.10 cm), fresh weight (50.31 g), dry weight (11.31 g), essential oil percentage (2%), dry weight yield (3393.5 kg/ha), and essential oil yield (69.19 kg/ha). The lowest values for plant height (71.50 cm), number of inflorescences (4.12), inflorescence length (17.75 cm), aerial fresh weight (15.68 g), dry weight (3.98 g), dry weight yield (1194.75 kg/ha), and essential oil yield (4.98 kg/ha) were observed in the K treatment, while the N treatment had the lowest essential oil percentage (0.44%). GC-MS analysis revealed that essential oil composition varied among treatments. The highest neral content (17.5%) was found in the P treatment; geraniol (7.9%) and neryl acetate (2.5%) were highest in the NPK treatment; geranial (32.1%) was most abundant in the K treatment; and geranyl acetate (73.2%) was highest in the NK treatment.Conclusion: The findings suggest that the combined application of biofertilizers, particularly the NPK combination, optimizes both yield and essential oil production in dragonhead under similar environmental conditions. It is anticipated that, under such conditions, and without reliance on chemical fertilizers, cultivating this medicinal plant within a sustainable agricultural framework can yield healthy, high-quality, and environmentally friendly essential oils.
Agriculture and horticulture
Hayder Mohammed Khudhair Al jazea; Bahram Abedy; Seyyed Hossein nemati
Abstract
Background and objectives: Mentha longifolia L. belongs to the Mentha genus and the mint family (Lamiaceae). This plant naturally grows in moist environments, such as riverbanks, and its cultivation in fields and greenhouses requires high-quality water. Water and soil salinity are among the most critical ...
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Background and objectives: Mentha longifolia L. belongs to the Mentha genus and the mint family (Lamiaceae). This plant naturally grows in moist environments, such as riverbanks, and its cultivation in fields and greenhouses requires high-quality water. Water and soil salinity are among the most critical agricultural challenges in hot and arid regions. In such areas, soil salinity and water scarcity are the primary factors that reduce the growth and yield of crops. Identifying and utilizing ecotypes and cultivars resistant to salinity stress can help prevent production losses. This study aims to investigate the effects of different water salinity levels on the morphological and physiological traits of three wild brookmint ecotypes to identify the most salt-tolerant ecotype.Materials and Methods: This study was conducted using a completely randomized design in factorial form with two factors at Ferdowsi University of Mashhad. The first factor was ecotype, with three levels (E1: South Khorasan, E2: Lorestan, E3: Fars), and the second factor was salinity stress, with four levels (0, 75, 100, and 150 mM sodium chloride). Salt stress treatments were applied beginning at the four-leaf stage, and at the eight-leaf stage, morphological traits were measured, including plant height, number of leaves, number of flowers, flower length, fresh and dry leaf weights, and fresh and dry root weights. Physiological traits assessed included chlorophyll a, chlorophyll b, total carotenoids, electrolyte leakage, total phenol content, total flavonoid content, proline content, and total carbohydrate content. Data was analyzed using Minitab 19 software.Results: The results showed that the main effects of ecotype and salinity stress and their interaction significantly influenced morphological traits such as plant height, root weight, and root dry weight. The main effects of ecotype and salinity stress on leaf weight and leaf dry weight were also significant. However, the main and interaction effects on traits such as number of leaves, number of flowers, and flower length were not significant. Salinity stress significantly reduced morphological traits in all ecotypes compared to the control, including plant height, leaf weight, dry weight, root weight, and dry weight. Regarding physiological traits, the main effects of ecotype and salinity stress, along with their interaction, significantly affected chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, electrolyte leakage, total flavonoid content, and proline content. The main effects of ecotype and salinity stress on total phenol content were significant, while their effects and interactions on carbohydrate content were not significant. Salinity stress led to a reduction in chlorophyll a, b, total chlorophyll, and carotenoids. Conversely, this stress increased proline content, electrolyte leakage, and the levels of total phenol and flavonoid compounds in the leaves compared to the control.Conclusion: Based on the evaluation of the measured traits in the three wild brookmint ecotypes, it was evident that these ecotypes responded differently to salinity stress. The results indicated that the E1 ecotype (South Khorasan) was superior to the others in terms of the traits studied and exhibited greater tolerance to salinity stress conditions.
Agriculture and horticulture
Afsoon Rezaie Allolo; Azizollah Kheiry; Mohsen Sanikhani; Maliheh Yaghoobi
Abstract
Background and objectives: Digitalis purpurea L., the most well-known species of the Digitalis genus, is a biennial plant containing cardiac glycosides (0.3 to 0.4%) in its leaves. These glycosides are extracted and used as natural medicines for treating heart diseases, with no chemical ...
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Background and objectives: Digitalis purpurea L., the most well-known species of the Digitalis genus, is a biennial plant containing cardiac glycosides (0.3 to 0.4%) in its leaves. These glycosides are extracted and used as natural medicines for treating heart diseases, with no chemical substitutes available, making them widely utilized annually. In recent years, using amino acids and growth regulators as alternatives to chemical compounds has gained popularity for enhancing secondary metabolites, improving the quality and quantity of agricultural products, and promoting sustainable agriculture. This study investigates the biochemical and growth responses of D. purpurea to foliar applications of glutamic acid and benzyladenine under greenhouse conditions to evaluate their effects on morphophysiological characteristics, yield improvement, and their potential as environmentally friendly alternatives to chemical fertilizers.Methodology: A completely randomized design with three replications was conducted in the research greenhouse of the University of Zanjan to evaluate the effects of foliar applications of benzyladenine (0.5 and 1 mM) and glutamic acid (1 and 2 mM), along with a control treatment (distilled water). Seeds were initially planted in a seedling tray containing cocopeat and peat moss. At the four-leaf stage, three seedlings were transplanted into plastic pots filled with a culture medium of field soil, cocopeat, and perlite (1:1:3 ratio). Greenhouse conditions were maintained at average day and night temperatures of 25°C and 18°C, respectively, with 80% relative humidity. Seedlings were irrigated weekly with 100 mL of complete Hoagland solution. Foliar spraying with the treatments began after seedling establishment in late June and was repeated four times at 10-day intervals. Leaf samples were collected 10 days after the final application for laboratory analysis. Data were analyzed using SAS software (version 9), and means were compared using Duncan’s multiple range test at a 5% probability level.Results: The application of 1 mM benzyladenine resulted in the highest total chlorophyll content (1.95 mg/g fresh weight), antioxidant activity (36.02%), and peroxidase enzyme activity (1.14 U/mg protein per minute). The maximum total carotenoid content (0.14 mg/g fresh weight), total phenol (12.52 mg gallic acid/g fresh weight), total flavonoid (2.86 mg quercetin/g fresh weight), and nitrogen content (1.46%) were achieved with one mM glutamic acid. Additionally, one mM glutamic acid application led to the highest catalase enzyme activity (4.09 U/mg protein per minute), fresh weight (123.51 g), and dry weight (47.38 g).Conclusion: The findings suggest that applying glutamic acid and benzyladenine at varying levels can significantly enhance the biochemical and growth characteristics of Digitalis purpurea L.
Agriculture and horticulture
Lida Barahmand Zadeh; Alireza Abdali Mshhadi; Abdolmahdi Bakhshandeh; Alireza Shafeinia; Amin Lotfi Jalal Abadi; Narges Soltani
Abstract
Background and Objectives: Lemongrass (Cymbopogon citratus (DC.) Stapf), a perennial plant from the Gramineae family, is renowned for its rich polyphenol compounds, having significant medicinal, cosmetic, and culinary applications. Enhancing the quantitative and qualitative yield of lemongrass is ...
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Background and Objectives: Lemongrass (Cymbopogon citratus (DC.) Stapf), a perennial plant from the Gramineae family, is renowned for its rich polyphenol compounds, having significant medicinal, cosmetic, and culinary applications. Enhancing the quantitative and qualitative yield of lemongrass is of considerable economic importance. Salicylic acid, a key regulator of physiological and biochemical processes, acts as an elicitor to enhance the accumulation of secondary metabolites in plants. Similarly, nitrogen plays a vital role in plant growth, improving yield quantity and quality. This study investigated the effects of nitrogen fertilizer and salicylic acid on various quantitative and qualitative traits of lemongrass.Methodology: A factorial experiment based on a randomized complete block design was conducted in 2021 at the Agricultural Sciences and Natural Resources research farm of the University of Khuzestan, Ahvaz, Iran. The experiment evaluated the effects of different levels of salicylic acid (0, 10 µM, and 100 µM) and nitrogen fertilizer (0, 50, 100, 150, and 200 kg/ha from a urea source) on lemongrass. Each treatment was replicated three times. In each fertilizer treatment, 20% of the nitrogen was applied after plant establishment, with the remainder applied in four stages alongside irrigation water to minimize leaching losses based on soil nitrogen content. Salicylic acid was applied via foliar spraying using a backpack sprayer when 70% of each plot was covered by lemongrass, with a second application 15 days later. Each plot measured 3 meters in width with six planting lines, each 3 meters long, 60 cm apart, and plants within lines were spaced 40 cm apart. The soil had a silty clay texture, pH of 7.5, and electrical conductivity of 2.6 dS/m. The studied traits included chlorophyll a, b, and total chlorophyll, carotenoid content, total fresh and dry weight, antioxidant activity percentage, total phenol content, and essential oil percentage and yield.Results: The interaction between salicylic acid and nitrogen fertilizer significantly influenced all studied traits except antioxidant activity percentage. Nitrogen fertilizer alone significantly affected antioxidant activity, with the highest percentage (89.8%) observed at 150 kg/ha of nitrogen. The highest levels of chlorophyll a, b, and total chlorophyll were achieved with no salicylic acid and 150 kg/ha of nitrogen, showing increases of 140%, 42%, and 116%, respectively, compared to the control (no salicylic acid or nitrogen). The highest total fresh and dry weight was obtained with 100 µM salicylic acid and 100 kg/ha of nitrogen, representing a 75% increase over the control. The highest essential oil percentage (0.87%) and yield (65.6 g/m²) were observed with 10 µM salicylic acid and 150 kg/ha of nitrogen. In contrast, the lowest essential oil yield (18.29 g/m²) and percentage (0.45%) were recorded in the absence of salicylic acid and nitrogen and with no salicylic acid but 150 kg/ha of nitrogen, respectively.Conclusion: Applying nitrogen fertilizer and salicylic acid enhanced the yield and percentage of essential oil, total dry matter, and total phenol content in lemongrass leaves compared to the control. The highest essential oil yield was achieved with 10 µM salicylic acid and 150 kg/ha of nitrogen fertilizer, demonstrating the synergistic effects of these treatments on lemongrass productivity and quality.
Agriculture and horticulture
Behrooz Esmaielpour; Elham Shojaei; Rasool Azarmi; Zahra Aslani; Seyed Karim Tahami; Mehdi Davari
Abstract
Background and objectives: Savory (Satureja hortensis L.) is an aromatic plant from the Lamiaceae family, known for its bioactive compounds, such as thymol and carvacrol, which possess antioxidant and antimicrobial properties. These compounds have applications in various industries, including food and ...
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Background and objectives: Savory (Satureja hortensis L.) is an aromatic plant from the Lamiaceae family, known for its bioactive compounds, such as thymol and carvacrol, which possess antioxidant and antimicrobial properties. These compounds have applications in various industries, including food and pharmaceuticals. Biofertilizers like mycorrhizal and Trichoderma fungi offer advantages over chemical fertilizers. These include reducing toxic substances in the food cycle, improving soil physical and chemical properties, and being cost-effective and environmentally sustainable. Trichoderma species promote plant growth through various mechanisms, including the biological control of soil-borne diseases by producing enzymes and antibiotics and direct antagonism against pathogenic fungi.Methodology: To evaluate the effect of Trichoderma harzianum on growth parameters, yield, and essential oil composition of savory in organic culture media, a factorial experiment was conducted using a completely randomized design with three replications in the Horticultural Science Greenhouse of Mohaghegh Ardabili University. The experimental treatments consisted of two factors: 1. Organic matter at three levels: Control (soil and sand mixture), Soil and sand mixture with 30% spent mushroom compost and Soil and sand mixture with 30% vermicompost. 2. Trichoderma harzianum inoculation at two levels: Inoculated and Non-inoculated (control). A 2 cm layer of coarse sand was placed at the bottom of the pots to ensure proper drainage. Savory seeds were initially grown in small pots and later transplanted to the main pots at the two- to three-leaf stage. Standard agronomic practices, such as irrigation and weeding, were maintained throughout the experiment. At the end of the study, vegetative traits (plant height, leaf area, dry weight of stem and root, number and length of secondary branches), physiological traits (chlorophyll index), nutrient content (N, K, P, Mg, Zn), and essential oil yield and composition were assessed.Results: The results demonstrated that organic fertilizers and Trichoderma inoculation significantly improved vegetative growth and quality traits compared to the control. The highest dry weight of aerial organs (4.82 g) was recorded in the vermicompost treatment, while Trichoderma inoculation resulted in 4.87 g. The highest chlorophyll index (26.86) was observed in plants treated with Trichoderma and vermicompost. Nutrient analysis showed that Trichoderma inoculation significantly increased phosphorus (3606.3 mg/kg), nitrogen (2.55%), and magnesium (55.64 mg/kg) content. In organic substrate treatments, vermicompost application resulted in the highest levels of zinc (47.87 mg/kg), nitrogen (3.06%), and phosphorus (4143 mg/kg). The highest carvacrol content (71.90%) was observed in Trichoderma-inoculated plants, while the highest essential oil yield (0.599 mL per pot) was found in plants treated with Trichoderma and vermicompost.Conclusion: The findings suggest that organic substrates combined with Trichoderma fungus can serve as an effective alternative to chemical fertilizers, enhancing both yield and essential oil quality in the organic cultivation of savory.
Agriculture and horticulture
Ahmad Bakhshi; Vahid Abdossi; Marziyeh Ghanbari Jahromi
Abstract
Background and objectives: Water availability is one of the most critical climatic factors influencing plant distribution worldwide. Drought stress, resulting from insufficient water availability, can induce plant morphophysiological, biochemical, and functional changes. Seaweed contains a high percentage ...
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Background and objectives: Water availability is one of the most critical climatic factors influencing plant distribution worldwide. Drought stress, resulting from insufficient water availability, can induce plant morphophysiological, biochemical, and functional changes. Seaweed contains a high percentage of polymer compounds capable of absorbing water molecules and forming a gel-like structure. Additionally, its rich composition of salts and essential minerals fulfills plant nutrient requirements, promotes growth and yield, enhances resistance to environmental stress, improves nutrient uptake from the soil, and boosts antioxidant properties. Tarragon (Artemisia dracunculus L.) is an herb widely used as a flavoring agent in the food industry, with its essential oil playing a key role in canning and perfumery. Because seaweed extract serves as a natural biofertilizer, providing essential nutrients and plant growth hormones while being environmentally friendly, it represents a viable alternative to chemical fertilizers. Moreover, it enhances plant resilience to various environmental stresses and contributes to sustainable food production. This study aims to investigate the effects of seaweed extract on the growth and biochemical characteristics of tarragon under drought stress conditions.Methodology: This study was conducted to investigate the growth, physiological, and biochemical characteristics of the medicinal plant tarragon (Artemisia dracunculus L.) under drought stress at four levels (100%, 80%, 60%, and 40% field capacity) and foliar application of aqueous Sargassum seaweed extract at three concentrations (0 g/L [control], 1 g/L, and 2 g/L). The experiment was carried out in the spring of 2023 in a greenhouse located in Damavand, using a factorial arrangement based on a completely randomized design with three replications. Four-leaf tarragon seedlings were obtained from the training farm of Damavand Technical and Vocational School and transplanted into three-liter pots. After a 10-day establishment period, drought stress was applied for 45 days, with foliar spraying of seaweed extract performed every two weeks, starting simultaneously with the onset of drought stress. Soil moisture levels in the pots were monitored daily by weighing them, and water was added as needed to maintain the target field capacity for each treatment. Plant sampling was conducted one week to 10 days after the completion of treatments, coinciding with the transition from vegetative to reproductive growth. Morphophysiological traits, including fresh and dry biomass, plant height, and the number of secondary branches, were measured. Additionally, biochemical parameters such as proline content, soluble carbohydrates, total phenol and flavonoid content, antioxidant activity, and essential oil yield and percentage were analyzed.Results: The results indicated that under severe drought stress (40% field capacity) and in the absence of seaweed extract application, there was a significant reduction in morphophysiological traits, including plant height, main stem diameter, number of secondary branches, fresh and dry weight of aerial parts, and photosynthetic pigments (chlorophyll a, chlorophyll b, and total chlorophyll). However, the application of seaweed extract mitigated the adverse effects of drought stress on tarragon. Under mild drought stress (60% field capacity) without seaweed extract application, the highest levels of total phenol (82 mg/g gallic acid), total flavonoid (64.33 mg/g quercetin), antioxidant activity (76%), and essential oil yield and percentage were observed. Drought stress also enhanced the activity of antioxidant enzymes, leading to increased synthesis of soluble carbohydrates and proline compared to the control. Among the tested seaweed extract concentrations, the application of 2 g/L had the most significant positive impact on the evaluated traits, further improving plant resilience and biochemical responses under drought-stress conditions.Conclusion: The overall findings of this study indicate that tarragon exhibits limited resistance to drought stress, with a noticeable decline in yield as stress intensity increases. Under drought conditions, the application of seaweed extract, particularly at a concentration of 2 g/L, effectively mitigated the adverse effects of stress by enhancing morphophysiological and phytochemical traits, including total phenol, flavonoid content, and essential oil yield. In most cases, the difference between 2 g/L and 1 g/L of seaweed extract was statistically significant, with 2 g/L demonstrating superior effectiveness. Therefore, the application of 2 g/L seaweed extract is recommended to improve drought tolerance and maintain yield in tarragon under water-limited conditions.
Agriculture and horticulture
Zeinab Sharifi; Hamid Reza Eisvand; Naser Akbari; Omid Ali Akbarpour
Abstract
Background and objectives: Allium jesdianum is a valuable medicinal and edible plant belonging to the Alliaceae family and is native to Iran. However, due to excessive harvesting in its natural habitat, it is currently endangered. This study aimed to promote the cultivation, conservation, and habitat ...
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Background and objectives: Allium jesdianum is a valuable medicinal and edible plant belonging to the Alliaceae family and is native to Iran. However, due to excessive harvesting in its natural habitat, it is currently endangered. This study aimed to promote the cultivation, conservation, and habitat restoration of this endangered species. To ensure its sustainability, wild ecotypes were cultivated in controlled agricultural environments, and the effects of plant nutrition and gibberellic acid on reproductive success and overall yield were evaluated.Methodology: A randomized complete block experiment with three replications was conducted during the 2021–2022 growing season at the research farm of Lorestan University. The experimental treatments included cow manure at two levels (0 and 40 t/ha), NPK biofertilizer (Azotobarvar-1, Potabarvar-2, and Phosphatebarvar-2) at two levels (0 and 100 g/ha), and gibberellic acid (GA₃) at two levels (0 and 250 ppm). Bulbs were collected from their natural highland habitat near the research site and cultivated in the field after being inoculated with NPK biofertilizer and gibberellic acid. Various morphological and yield-related traits were measured, including plant height, fresh and dry leaf weight, weight and diameter of mother and daughter bulbs, daughter bulb production, economic yield, and biological yield. Data were analyzed using SAS 9.4 software, and treatment means were compared using the LSD test at a 5% significance level.Results: Applying cow manure, NPK biofertilizer, and gibberellic acid individually or in combination significantly influenced most vegetative and yield-related traits. However, the number of leaves per plant showed no significant variation. The highest plant height (26.53 cm), fresh leaf weight (8.24 g per plant), and dry leaf weight (2.84 g per plant) were recorded in the treatment combining cow manure, NPK biofertilizer, and gibberellic acid. Fertilizer and gibberellic acid application led to an approximately 2.5-fold increase in fresh leaf yield and an 18% improvement in biological yield compared to the control. The combination of cow manure and biological fertilizer had the most substantial impact on plant growth parameters. The weight and diameter of the mother bulb were significantly influenced by both the main effects and their interactions, with the highest values (3.58 g per plant and 22.52 mm) observed under the combined application of cow manure, biological fertilizer, and gibberellic acid. Similarly, the weight and diameter of daughter bulbs followed the same pattern. Reproductive success in A. jesdianum was significantly improved with the combined application of cow manure, biological fertilizer, and gibberellic acid. This treatment resulted in the highest bulb yield, averaging 13.33 bulbs per unit area.Conclusion: The results indicate that the integrated application of cow manure, NPK biofertilizer, and gibberellic acid significantly enhances plant yield and daughter bulb production. Therefore, this approach is recommended for farmers seeking to improve A. jesdianum cultivation while reducing dependence on chemical fertilizers.
Agriculture and horticulture
A. Kamyab; D. Samsampour; N. Ahmadinasab; A. Bagheri
Abstract
Background and objectives: Drought is one of the most important factors limiting the production of crops in the world, which can adversely affect the growth and performance of plants. Bacterial endophytes, as one of the microorganisms symbiotic with plants, play an essential role in improving the growth ...
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Background and objectives: Drought is one of the most important factors limiting the production of crops in the world, which can adversely affect the growth and performance of plants. Bacterial endophytes, as one of the microorganisms symbiotic with plants, play an essential role in improving the growth and performance of their host plants under drought-stress conditions. Considering the problems of water scarcity in Iran, this study was conducted to investigate the effect of the bacterial endophyte Agrobacterium deltaense isolated from the bitter myrtle (Salvia mirzayanii) plant on some quantitative and qualitative characteristics of thyme plants under drought stress.Methodology: The bacterial endophyte was identified using morphological, physiological and molecular methods. Then, the sterilized Thyme seeds were cultivated under standard conditions and transferred to pots after two months. Six months after transplanting the culture to the pot, Thyme plants were inoculated in three stages weekly using A. deltaense bacterial endophyte. The bacterial suspension was adjusted in an NB culture medium with a 1 × 108 ml concentration. Then, they were applied as foliar spraying to the aerial parts of the plants and injected into the roots. To ensure the presence of endophytes after one month of foliar spraying to the aerial parts and injection to the roots, the bacterial endophyte establishment test was performed in the plant, and then drought stress was applied for three months, and then the morphological traits, Physiological and biochemical properties of thyme plant were evaluated. A factorial experiment in the form of a randomized complete design was performed in three replications on the research greenhouse of the Horticulture Department of Hormozgan University in 2021. The treatments were determined at four levels of drought stress (0, 25, 50 and 75% of field capacity) and two levels of bacterial inoculation (no inoculation and inoculation with A. deltaense). The assessed traits included: height, fresh and dry weight of stem and root, percentage of electrolyte leakage, chlorophyll a and b, total chlorophyll, carotenoid, prolin, soluble sugar, Total Phenolic Content, Essential Oil Percentage and mycorrhizal dependency.Results: Drought stress led to significant effects on the reduced performance of garden thyme plants, including decreased stem height, fresh and dry weight of stems and roots, chlorophyll a and b, total chlorophyll, and carotenoids. However, under severe drought stress (75% field capacity), inoculation of garden thyme with the endophytic bacterium A. deltaense resulted in a significant increase in stem height (41.35%), root dry weight (71.85%), root fresh weight (74.35%), stem dry weight (83.22%), stem fresh weight (37%), chlorophyll a (97.15%), chlorophyll b (09.41%), total chlorophyll (77.20%), carotenoids (25%), and caused a significant reduction in electrolyte leakage by 90.5% compared to the control. Furthermore, the presence of the endophytic bacterium A. deltaense, in contrast to its absence under drought stress conditions, led to an increase in proline (17.07%), soluble sugars (15.09%), total phenolics (27.39%), and essential oil percentage (20%), mycorrhizal dependency (84%) compared to the control.Conclusion: The study's results suggest that beneficial microorganisms, including bacterial endophytes, can be used as a suitable way to increase plant resistance to drought. This potential can be used for sustainable agriculture and reduced slaughter limits in dry and low-water areas. In the case of the use of A. deltaense bacterial endophyte in garden aviation slaughter under dry conditions, improvement in the growth and functioning of plants can be observed, as well as an increase in the percentage of essential oil and phenol content, which is an indicator of their quality and effective therapeutic compounds. This increase not only helps promote plants' medicinal properties but also increases their economic and commercial value.
Agriculture and horticulture
Z. Baharmast; M. Hassanpour Asil; M. B. Farhangi; A. Sahraroo
Abstract
Background and objectives: Pink evening primrose is one of the world's most well-known and economically valuable medicinal plant species. It has also been cultivated as an ornamental and medicinal plant in Iran. In addition, its seed oil is used in the pharmaceutical, food, cosmetic, and healthcare industries. ...
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Background and objectives: Pink evening primrose is one of the world's most well-known and economically valuable medicinal plant species. It has also been cultivated as an ornamental and medicinal plant in Iran. In addition, its seed oil is used in the pharmaceutical, food, cosmetic, and healthcare industries. Micronutrients and biofertilizers can enhance the quality of agricultural products. Therefore, this study was conducted to investigate the effect of arbuscular mycorrhizal fungi and zinc foliar spraying on the nutrient uptake morphophysiological and biochemical characteristics of pink evening primrose.Methodology: This research was conducted on evening primrose for one year, from October 2022 to September 2023. For this purpose, evening primrose seeds were first grown for 120 days in greenhouse conditions in size 10 pots and then at the time of transplanting to the main pot, they were inoculated with Glomus intraradices arbuscular mycorrhizal species, and inoculation was carried out at two levels of inoculation and non-inoculation during the transfer of the seedlings of the main pot. This experiment was carried out factorially in a completely randomized design and foliar application of zinc element in zinc sulfate at three levels of zero (control), 3 and 5 mg/L in three replications at the eight-leaf stage. Before planting the plant, samples were taken from the soil mixture used, and the physicochemical test of the soil included The concentration of nitrogen, potassium, phosphorus and biomass carbon elements. The examined traits include Morphological traits (wet and dry weight of shoot, number of flowers per stem, flower diameter, length of flowering period, number of leaves, number of capsules, number of seeds in capsule, number of lateral branches) and number of mycorrhizal spores in the soil and physiological traits including chlorophylls a, b and total, carotenoid, phenol and flavonoid and antioxidant and activity of catalase and peroxidase enzymes were evaluated in leaves.Results: The results showed that in the foliar treatment with 5 mg/l zinc sulfate, the number of flowers per plant, number of capsules per plant, number of seeds per plant, seed yield, number of internodes, number of secondary stems, fresh and dry weight of shoot and flavonoid phytochemical traits, antioxidant, catalase and peroxidase and in addition elements of phosphorus, zinc, boron, manganese, iron and copper were significantly different at the 1% probability level. Carotenoid, nitrogen and potassium elements were found to have a significant difference at the 5% probability level. The effect of inoculation treatment with arbuscular mycorrhizal fungus on the traits of number of flowers per plant, number of capsules per plant, number of seeds per plant, seed yield, flower diameter, stem diameter, leaf area, number of leaves, fresh and dry weight of shoot, plant height and length flowering period and in addition, total chlorophyll, phenol, flavonoid, antioxidant and catalase and elements of nitrogen, zinc, boron, manganese, iron and copper were significantly different at the 1% probability level. The traits of the number of secondary stems, carotenoids, and peroxidase were significant at the 5% probability level. The interaction effect of foliar spraying treatments with zinc sulfate 5 mg/litre and arbuscular mycorrhizal fungus on shoot weight and total chlorophyll at the 1% probability level, and the number of flowers, chlorophyll a, catalase and zinc element was observed to be significant difference at 5% probability level. The comparison between the treatments showed that the foliar treatment with zinc sulfate 5 mg/litre, along with the inoculation of arbuscular mycorrhizal fungus, had the most significant effect on increasing the amount of flowering, seed yield and phenolic compounds and catalase and peroxidase enzymes.Conclusion: In general, it can be concluded that among the treatments used, foliar spraying treatment with zinc sulfate (5 mg/litre) along with arbuscular mycorrhizal fungus can achieve high flower and seed yield by affecting the availability of nutrients and increasing vegetative growth. It can also increase the amount of chlorophyll and total carotenoid, flavonoid, antioxidant, catalase, and peroxidase of this valuable plant.
Agriculture and horticulture
M. Khoobbakht; R. Rahimi; Kh. Karimzadeh
Abstract
Background and objectives: Saffron is one of the most iconic and valuable plants in Iran, with a cultivation history that spans centuries. It is a key agricultural product for export, contributing significantly to the country's foreign currency earnings. As the world's leading saffron producer, Iran ...
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Background and objectives: Saffron is one of the most iconic and valuable plants in Iran, with a cultivation history that spans centuries. It is a key agricultural product for export, contributing significantly to the country's foreign currency earnings. As the world's leading saffron producer, Iran accounts for 60% of global production. This study aims to analyze the patterns of energy use in saffron cultivation and explore the relationships between energy inputs and yield in the west of Isfahan province, Iran.Methodology: This research gathered the necessary data through questionnaires and interviews with saffron farmers. The inputs analyzed in the study included human labor, machinery, diesel fuel, chemical and organic fertilizers, irrigation water, electricity, and seed energy. The energy equivalent for each input was determined by multiplying the input quantities by their respective energy coefficients. Based on the energy equivalents of both inputs and outputs, key energy indices such as energy ratio (energy use efficiency), energy productivity, and specific energy were calculated. The energy ratio (energy use efficiency) was calculated using the formula: Energy Ratio = Energy Output (MJ ha⁻¹) / Energy Input (MJ ha⁻¹). To establish a mathematical relationship between energy inputs and yield, the Cobb-Douglas production function was applied. In this study, energy requirements were categorized into four groups: direct, indirect, renewable, and non-renewable. The marginal physical productivity (MPP) method was employed to analyze the sensitivity of energy inputs in saffron production. This method assesses how the performance changes when one unit of energy input is increased, while holding other production factors constant. A positive MPP value for any input suggests that increasing the input will result in higher output, implying that the input should continue to be used until the resource reaches its limit. Conversely, a negative MPP value indicates that additional units of the input decrease performance, signaling that further input use would be inefficient.Results: The results of this study revealed that the corm used for cultivation (seed) accounted for the highest proportion of energy consumption in saffron production, contributing 54.11%, followed by manure (13.51%) and electricity (11%). Notably, the proportion of renewable energy in saffron cultivation exceeded that of non-renewable energy consumption. Two methods were employed to calculate energy use efficiency in saffron production: one based on the total outputs, including stigma, leaf, and corm, and the other considering only the saffron stigma. For this study, the energy use efficiency was found to be 0.002 when based solely on saffron stigma. The R² value for the Cobb-Douglas production function, which was based on energy consumption, was estimated at 0.84, indicating that the model explained 84% of the variability in performance based on the five input factors: labor, irrigation water, machinery, chemical fertilizers, and animal fertilizers. The results of the Cobb-Douglas model demonstrated that the energy inputs of human labor, machinery, chemical and animal fertilizers, and irrigation water had a significant impact on yield. Furthermore, the sensitivity analysis revealed that human labor had the highest marginal physical productivity (MPP) among all input energies. With an MPP value of 0.87, human labor had the most substantial effect on saffron production, significantly influencing the overall output compared to other energy inputs.Conclusion: The results of this study indicated that the total energy consumed in saffron production was 138,319 MJ/ha. Of this, renewable energy accounted for 16.46% of the total energy used. The key energy indices for saffron production were as follows: energy use efficiency was 3.7, energy productivity was 0.24 kg MJ⁻¹, specific energy was 4.8 MJ kg⁻¹, and net energy was 377,600 MJ ha⁻¹. These values provide a comprehensive overview of the energy dynamics involved in saffron cultivation, highlighting both the energy intensity and efficiency of the production process.
Agriculture and horticulture
O. Heidarpour; B. Esmaielpour; A. Soltani; zahra aslani
Abstract
Background and objectives: Savory (Satureja hortensis L.) is one of the most important medicinal plants that grows in different parts of the world, including Iran. Water deficit has adverse effects on physiological processes such as photosynthesis, nutrient absorption, ...
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Background and objectives: Savory (Satureja hortensis L.) is one of the most important medicinal plants that grows in different parts of the world, including Iran. Water deficit has adverse effects on physiological processes such as photosynthesis, nutrient absorption, development and division of cells, and accumulation and transfer of nutrients, thus reducing the performance of plants. In contrast, biofertilizers play a prominent role in the growth and development of plants by improving the absorption of nutrients and sufficient water through changes in the physicochemical properties of the soil. This study aimed to investigate the effect of drought stress, growth-promoting bacteria (PGPRS) and vermicompost on the yield, amount of nutrients and essential components of the savory plant.
Materials and methods: A factorial experiment based on a randomized complete block design with three replications was conducted at the Research Farm at the Mohaghegh Ardabili University, Iran, from 2016-2017. Treatments included three levels of drought stress (Full irrigation (S1), Water cut at 50% of flowering (S2), and water cut in early stages of flowering (S3), four vermicompost levels (including 0, 1, 1.5 and 2 t. ha-1) and included inoculation with microorganisms at three levels (non-inoculation, inoculation with Streptomyces and Pseudomonas fluorescens p15). Before planting, the seeds were inoculated with biological stimulants. Then, seeds were cultivated in rows at a distance of 25 cm between the rows, 20 cm on rows and at a depth of 0.5 cm. To apply the irrigation treatment, the field's soil was investigated in the horizon of the plant roots up to a depth of 20 cm by digging a profile. The weight method was used to control water. Field capacity (FC) and permanent wilting point (PWP) were measured using intact samples 24 hours after soil saturation for field capacity and placed in a suction device with 15 atmospheres of negative pressure for permanent wilting point. The corresponding values for the soil at a depth of 0 to 30 cm were determined according to the layering of the soil, and from their difference, the amount of usable soil water (AW) was determined. During the test, the usable water (depending on the plant's growth stage) was determined by the soil sampling cylinder and transferred to the oven in the form of moisture percentage by weight. The examined parameters included plant height, shoot dry weight, root dry weight, and concentration of phosphorus, potassium, and essential oil components.
Results: Based on the obtained results, drought stress, vermicompost, and inoculation with PGPRS had a significant effect on the measured parameters. So that the maximum plant height (62.36 cm), shoot dry weight (28.72 grams) and root dry weight (6.35 grams), phosphorus (1.3 percent) and potassium absorption (3.3 percent) were obtained under non-stress conditions, application of vermicompost two tons per hectare of and inoculation with Streptomyces bacteriaand the lowest amount of plant height (22.33 cm), shoot dry weight (18.33 grams), dry weight roots (3.07 grams), phosphorus (0.85 percent) and potassium (1.2 percent) were observed in the planting beds without vermicompost application and non-inoculation with biological stimulants and in severity drought stress. Also, the highest amount of carvacrol (62%) and gamma-terpinene (26.9%) was obtained in the treatment of severe drought stress and beds containing two tons per hectare of vermicompost in plants inoculated with Streptomyces.
Conclusion: Vermicompost with growth-promoting bacteria can be a sustainable agricultural fertilizer containing beneficial microorganisms that improve the growth performance and essential components of savory plants under drought stress and non-stress conditions.
Agriculture and horticulture
T. Sajadian; Kh. Abdollahi; J. khorshidi
Abstract
Background and objectives: Saffron (Crocus sativus L.) is one of the most expensive spices in the world, and due to the high demand for it in the world markets, its cultivation is developing strongly. In addition to genetics, the region's climate and soil characteristics also affect the quantity ...
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Background and objectives: Saffron (Crocus sativus L.) is one of the most expensive spices in the world, and due to the high demand for it in the world markets, its cultivation is developing strongly. In addition to genetics, the region's climate and soil characteristics also affect the quantity and quality of the product. Therefore, identifying regions, whose climatic and soil conditions are close to the optimal conditions for saffron production will help us achieve the most favorable quantitative and qualitative performance.
Materials and methods: In the present study, saffron was cultivated in six different regions of Kurdistan province (Sanandaj, Kamyaran, Ghorveh, Dehgolan, Divandarreh, and Marivan) as a randomized complete block design, and their functional and phytochemical characteristics were evaluated during three years (2020-2022). The saffron corms used in this research were prepared from Torbat-e Heydarieh city. In each region, land with an area of 25 m2 was selected. After preparation, three plots with dimensions 2x2 m with 1m distances were created. Each experimental plot consisted of 10 rows, and in each row, 20 holes were made with a depth of 15 cm and a distance of 10 cm from each other, and then one corm was planted in each hole. Irrigation was done twice a year (late September and late October). During the flowering season, saffron flowers were harvested, and their functional and phytochemical characteristics (number of flowers, dry flower yield, dry stigma yield, stigma length, crocin, and safranal content of the stigma) were measured. Total monthly precipitation and average monthly temperature for each region during the research period were obtained from nearest meteorological station. The physicochemical properties of soil samples from the studied regions were evaluated in the laboratory. Finally, the mean comparison of data (using Duncan’s multiple range test) and correlations between climate and soil data with functional and phytochemical traits (using the Pearson method) were obtained by SPSS software.
Results: The results indicated that the maximum stigma yield in all three years belonged to saffron cultivated in Kamyaran (0.13±0.009, 1.27±0.085 and 1.54±0.052 g/m2 in 2020, 2021, and 2022, respectively). In all three years, the highest crocin content was obtained from the stigmas harvested from Divandarreh farm (53.01±15.77, 92.54±26.6 and 143.07±5.12 mg/g dry stigma in 2020, 2021 and 2022, respectively). The highest mean of safranal content in the year 2020 (4.09±0.38 mg/g dry stigma), 2021 (2.48±0.44 mg/g dry stigma), and 2022 (5.05±0.14 mg/g dry stigma), belonged to the saffron of Kamyaran (no significant difference with other regions except Marivan), Marivan (no significant difference with Dehgolan and Divandarreh) and Divandarreh (no significant difference with other regions except Kamyaran), respectively. Dry flower yield and stigma yield showed a significant negative correlation with clay (r= -0.329* and r= -0.356**, respectively), organic matter (r= -0.422** and r= -0.428**, respectively) and nitrogen (r= -0.437** and r= -0.444**, respectively), and a significant positive correlation with potassium (r= 0.544** and r= 0.561**, respectively) and phosphorus (r= 0.410** and r= 0.435**, respectively). The crocin content of stigma had a significant positive correlation with clay (r= 0.557**) and pH (r= 0.438**) and a significant negative correlation with sand (r= -0.461**). Safranal had no significant correlation with soil characteristics and altitude. Also, significant correlations were obtained between the measured traits and average monthly temperature and total monthly precipitation.
Conclusion: Generally, regions of Kurdistan province with less rainfall in spring, summer and early autumn; more rainfall in late autumn and during winter; higher average monthly temperature; with medium-textured soils containing more phosphorus and potassium, lower nitrogen and organic matter, and slightly alkaline pH, were identified as more suitable regions for saffron production. Based on all measured quantitative and qualitative traits, among the studied regions, Kamyaran had the most suitable conditions for saffron production.
Agriculture and horticulture
F. Beheshti Qolezo; M. Moghaddam; L. Samiei
Abstract
Background and objectives: Maintaining medicinal plants' quality and effective compounds is a fundamental challenge. Salvia L. has antioxidant, anti-inflammatory, and antimicrobial properties and is a rich source of biological compounds that destroy free radicals. Salvia ...
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Background and objectives: Maintaining medicinal plants' quality and effective compounds is a fundamental challenge. Salvia L. has antioxidant, anti-inflammatory, and antimicrobial properties and is a rich source of biological compounds that destroy free radicals. Salvia virgate Jacq. has several biological activities and is used to treat wounds and various skin diseases and prevent blood cancer. Cadmium is one of the most toxic heavy metals due to its long biological half-life, significant mobility in soil, and capacity to be absorbed by plants. Cadmium's negative effects on plant growth, and physiological and biochemical activities reduce plant quality and performance. Sodium nitroprusside is involved in biological processes and responds to various stresses by releasing nitric oxide (NO).
Methodology: To investigate the effect of different levels of sodium nitroprusside on improving the response of salvia virgata to cadmium stress under in vitro conditions, an experiment was conducted in the Research Institute of Plant Sciences of the Ferdowsi University of Mashhad with a factorial design based on a completely randomized design with four replications. The studied factors included different levels of cadmium (0 (control), 25, 50, and 100 µM) and sodium nitroprusside (0 (control), 15, and 30 µM). Murashig and Skoog culture media were used for seed cultivation. In this experiment, different amounts of cadmium nitrate were added to the culture medium before adjusting the pH. Sodium nitroprusside was added to the medium after autoclaving and a sub-laminar filter due to its sensitivity to high temperatures. At first, the seeds were sterilized with 70% alcohol and 2% sodium hypochlorite; then, they were planted in a culture medium. After three months of growth, the seedlings were removed from the culture medium. Growth traits include the fresh and dry weight of the aerial part, root, and whole seedling, and physiological and biochemical traits including photosynthetic pigments (measurement of chlorophyll a, chlorophyll b, carotenoid, total chlorophyll, and total photosynthetic pigment), flavonoid, total phenol, carbohydrate, proline, protein, and antioxidant activity were measured. The data obtained from this research were analyzed by Minitab software. The mean comparisons were done by the Bonferroni test at the five percent probability level.
Results: According to the results of the analysis of variance of the data, the interaction effect of cadmium and nitroprusside on seedling fresh weight, chlorophyll a, chlorophyll b, carotenoid, total photosynthetic pigments, total phenol, carbohydrate and proline at the probability level of one percent and seedling dry weight, total chlorophyll, flavonoid, and protein were significant at the five percent probability level. The interaction effect of treatments on antioxidant activity was not significant, but their simple effects were significant. The results of the mean comparison of the data indicated that cadmium stress decreased the fresh and dry weight of seedlings, chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, and total photosynthetic pigments in S. virgata, and the application of sodium nitroprusside led to the improvement of these traits; so that the application of 30 μM sodium nitroprusside under cadmium stress with a 50 μM concentration showed the highest fresh and dry weight of seedlings and the proline content, and the application of 15 μM sodium nitroprusside under cadmium stress with a 25 μM concentration showed the highest amount of photosynthetic pigments. Also, this research indicated that cadmium stress increased antioxidant activity, total flavonoid, total phenol, soluble carbohydrate, proline, and protein in the S. virgata plant. However, sodium nitroprusside application improved these negative effects of cadmium stress. So, the application of 30 μM sodium nitroprusside led to an increase in total flavonoid, total phenol, soluble carbohydrate, and protein under cadmium stress conditions at 25 μM concentration.
Conclusion: The results showed that cadmium stress reduces plant growth and physiological and biochemical functions, but sodium nitroprusside application could improve cadmium's negative effects. These findings show that sodium nitroprusside can be used as an effective instrument in cadmium stress management in medicinal plants and help to improve the growth and quality of these plants. This research, in addition to enhancing our knowledge about the mechanisms of plants' response to cadmium stress, helps to analyze the effect of sodium nitroprusside in exposure to environmental life pollutants.
Agriculture and horticulture
Farhad Bagheri fard sharabiani; Esmaeil Chamani; Mousa Torabi Giglou; Alireza Ghanbari; Younes Pourbeyrami hir
Abstract
Background and objectives: The beneficial effects of the chamomile plant have been attributed to its essential oil, so any factor that affects the quantity of its essential oil will be of interest to researchers. To investigate the effect of plant growth regulators salicylic ...
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Background and objectives: The beneficial effects of the chamomile plant have been attributed to its essential oil, so any factor that affects the quantity of its essential oil will be of interest to researchers. To investigate the effect of plant growth regulators salicylic acid and methyl jasmonate on the production of secondary metabolites in chamomile plants, this experiment was conducted under the native in vitro conditions of Sharbian City.Methodology: To conduct this research, chamomile seeds were collected from Sharbian (N ʺ52 58 37 and E ʺ06 ʹ11 ˚), East Azerbaijan province. After transfer, the seeds were sterilized for 15 minutes in a detergent. Their surfaces were disinfected with 70% alcohol for 45 seconds and then with sodium hypochlorite for 30 minutes. After surface disinfection, they were washed twice with distilled water. The basic culture medium in this study was the MS culture medium. All cultures were placed in the growth chamber at a temperature of 24±2°C and 16 hours of light and 8 hours of darkness. A factorial experiment was performed in a complete random design with three replications. Test treatments included salicylic acid (SA) and methyl jasmonate (MeJA) at five levels (0, 50, 100, 200, 400 μM). Minguez-Mosquera and Perez-Galvez methods were applied to determine photosynthetic pigment amounts. The amount of phenolic compounds in the plant extract was measured with a slight modification based on the Slinkard and Singleton method with the Folin-Ciocalteau reagent. The data related to this research were analyzed using SAS V.9.g.1 statistical software. The comparison of treatment averages was done with Duncan's test at 5% and 1%. Graphs were drawn using Microsoft Excel software.Results: The analysis of variance showed that the interaction effect of the applied treatments on the traits of stem weight, root weight, stem length, and root length is significant at the 1% probability level. In addition, it is significant on the number of stems at the 5% probability level. The comparison of the averages showed that the highest amount of stem weight was obtained in the interaction effect of (50 µM) SA and (200 µM) MeJA, and the lowest amount of stem weight was obtained in the interaction effect of (400 µM) SA and (400 µM) MeJA treatment. The comparison of the means shows a significant difference in this trait. The highest amount of root weight was obtained in the interaction effect of (100 µM) SA and (100 µM) MeJA, and the lowest amount of root weight was obtained in the interaction of (400 µM) SA and (400 µM) MeJA treatment. Came. A comparison of the averages showed that the highest number of stems was obtained in the interaction of (100 µM) SA and (50 µM) MeJA, and the lowest number of stems was obtained in the interaction of (400 µM) SA and (200 µM) MeJA. The comparison of the means showed the significance of the stem and root length traits. The highest value of these two traits was due to the interaction of (50 µM) SA and (100 µM) MeJA treatments, and the lowest value of stem length was in the combination of (400 µM) SA and (µM) treatments. 400) MeJA and root length were measured from the combination of SA (400 µM) and MeJA (200 µM) treatments. In the biochemical traits, variance analysis of the data showed that the effect of SA levels on the amount of chlorophyll a, b, carotenoid, total chlorophyll, phenol, and flavonoid in all three wavelengths was significant at the 1% probability level.Conclusion: In this experiment, it was shown that metabolite production depends not only on enzyme activity but also on stimulant concentration. Increasing the stimulus more than usual not only increases metabolism but also reduces or stops the production of metabolites through the reduction of enzyme activity (probably through the reduction of the corresponding gene expression).
Agriculture and horticulture
Kosar Taheri Boukani; Abbas Hassani; MirHassan Rasouli-Sadaghiani; Mohsen Barin; Ramin Maleki
Abstract
Background and objectives: Basil (Ocimum basilicum L.) is an annual herbaceous plant belonging to the mint family (Lamiaceae). Its fresh and dried leaves and essential oils are used in the food, pharmaceutical, and cosmetic industries. In recent years, the use of symbiosis with plant beneficial rhizospheric ...
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Background and objectives: Basil (Ocimum basilicum L.) is an annual herbaceous plant belonging to the mint family (Lamiaceae). Its fresh and dried leaves and essential oils are used in the food, pharmaceutical, and cosmetic industries. In recent years, the use of symbiosis with plant beneficial rhizospheric microorganisms including rhizobacteria and endophytic fungi has been considered as a cost-efficient and sustainable strategy to alleviate the adverse effects of environmental stresses such as salinity. Therefore, the present study was conducted in the research greenhouse of Urmia University. It evaluated the effect of inoculation with growth-promoting microorganisms on some growth, physiological, and phytochemical characteristics of basil plants under salt-stress conditions.Methodology: This research was conducted as a factorial experiment in a completely randomized design with three replications. The experimental factors were inoculation with microorganisms at three levels (control without inoculation, inoculation with Serendipita indica, and inoculation with a mixture of Pseudomonas areuginosa, P. putida, and P. fluorescens) and salinity stress at four levels (0, 40, 80 and 120 mM of NaCl). For inoculation, the germinated seeds were separately inoculated with S. indica suspension (5×105 spores per ml) and inoculum containing a mixture of Pseudomonas bacteria (1.61×109 cells per ml) and planted in prepared pots. The pots were irrigated with ordinary tap water until the plants were eight-leafed, and from this stage onwards, salinity stress treatments were applied by dissolving different concentrations of NaCl in the irrigation water and continued until the full flowering stage. In the full flowering stage, plant samples were collected and root colonization percentage by fungus, growth parameters (plant height, stem diameter, number and total length of lateral branches, leaf number and area, inflorescence length, fresh and dry weight of leaf and stem), leaf relative water content (RWC), photosynthetic pigments, concentration of leaf nutrients (N, P, K, Na and Cl), essential oil content and yield were evaluated. For essential oil extraction, shade-dried samples were hydro-distilled using a Clevenger-type apparatus.Results: The results showed that due to salinity stress, the percentage of root colonization by S. indica, growth parameters, RWC, photosynthetic pigments, essential oil content, yield, N, P, and K content, and K/Na ratio decreased while Na and Cl content increased. In addition, all evaluated parameters in inoculated plants were higher than in non-inoculated plants except Na and Cl content. The highest and lowest rates of growth parameters, RWC (74.47 and 72.39%), essential oil yield (0.23 and 0.17 ml/pot), and N content of leaves (1.36 and 1.14%) were obtained in plants inoculated with S. indica and non-inoculated plants, respectively. The highest and lowest amounts of chlorophyll a (0.87 and 0.74 mg/g fw), chlorophyll b (0.41 and 0.37 mg/g fw), essential oil percentage (1.24 and 1.05%), K content (5.15 and 3.97%), P content (0.29 and 0.24%) and the K/Na ratio (10.05 and 4.07), were observed in plants inoculated with a mixture of Pseudomonas bacteria and non-inoculated plants, respectively. Also, the lowest Na (1.34%) and Cl (2.93%) accumulation was observed in plants inoculated with Pseudomonas bacteria and S. indica fungus, respectively.Conclusion: According to the results of this study, the use of plant growth-promoting microorganisms (S. indica fungus and a mixture of Pseudomonas bacteria) can alleviate adverse effects of salinity stress on the growth and essential oil production of the basil plant by increasing the absorption of water and nutrients, preserving photosynthetic pigments and reducing the accumulation of toxic ions.
Agriculture and horticulture
Vahideh Samadiyan-Sarbangholi; B. Abaszadeh; Fatemeh Sefidkon; Mehrdad Yarnia
Abstract
Bachground and objective: Deficiency or excess of any growth factor leads to morphological, anatomical, physiological, and growth disorders in plants. Drought stress means a lack of water in the plant. This situation occurs when the amount of transpiration exceeds the amount of water absorption. Low ...
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Bachground and objective: Deficiency or excess of any growth factor leads to morphological, anatomical, physiological, and growth disorders in plants. Drought stress means a lack of water in the plant. This situation occurs when the amount of transpiration exceeds the amount of water absorption. Low irrigation (watering less than the optimal water requirement of the plant) is a strategy to save water, but it affects the plant at a particular stage of growth or the entire season. Biofertilizers develop the root system, changing host plant water relations and plant metabolism. They also activate the defense system, improving access to minerals and tolerance to drought in the host plant, making it environmentally friendly and natural. To manage the prevailing water crisis, one should look for solutions such as reducing water consumption and stopping irrigation at all stages of growth. This is without harming the plant's final performance. In addition, due to the importance of medicinal plants and increasing their biomass, biological fertilizers and the adjustment of drought stress effects have a special place. This experiment was carried out to investigate the effectiveness of Satureja bachtiarica Bunge. against dehydration at different stages of growth. It also investigated the consumption of mycorrhizal fungi and growth-stimulating bacteria to manage plant production with high quality and quantity.Methodology: The experiment was carried out in the form of split plots in the form of a randomized complete block design in three replications in the research farm of Islamic Azad University, Tabriz branch, in 2018. The main and sub-factors were included in 4 water stress (I1: without stress, I2: cut irrigation in stem elongation stage, I3: cut irrigation at the budding stage and I4: cut irrigation at 50% flowering stage) and 5 biofertilizer levels (b1: without inoculation, b2: inoculation with Funneliformis mosseae, b3: inoculation with Rhizophagus irregularis, b4: Funneliformis mosseae + Rhizophagus irregularis and b5: Azosprillium+Pseudomonas+Azetobacter), respectively. The harvest was in full flowering stage.Results: The comparison of the average of irrigation interruptions showed that the most number of leaves, stem diameter, canopy extent, root weight, leaf yield, flowering stem yield, and flowering branch yield belonged to the irrigation interruption at the 50% flowering stage. Inoculation with Funneliformis mosseae mycorrhizal fungus achieved the highest leaf yield (912.06 kg/ha), flowering stem yield (1071.25 kg/ha) and flowering branch yield (1983.32 kg/ha) in inoculation with Azosprillium + Pseudomonas + Azotobacter was observed. The highest percentage of essential oil was found in inoculation with Funneliformis mosseae with an average of 1.76%. The maximum average yield of essential oil at 30.50 kg/ha was observed in the inoculation treatment with Azosprillium + Pseudomonas + Azotobacter. The results of the comparison of the average of the interaction effect showed that the maximum height of the plant and the number of inflorescences with an average of 61.72 cm and 30.46 per plant were found in the interaction effect of the treatment of interruption of irrigation at the stemming stage and inoculation of Rhizophagus irregularis + Funneliformis mosseae, which is about 31 and 39 The percentage increased compared to their lowest value. Stopping irrigation in the budding stage ×Funneliformis mosseae had the highest percentage of essential oil with an average of 2.33%. Stopping irrigation in the stemming stage ×Rhizophagus irregularis had the lowest essential oil percentage. The highest leaf yield (1212.83 kg/ha), flowering stem yield (1494.75 kg/ha), flowering branch yield (2707.58 kg/ha) and essential oil yield (44.39 kg/ha) in the interaction effect of cutting × Azosprillium + Pseudomonas + Azotobacter irrigation was observed at the 50% flowering stage, which increased by 70, 82, 81 and 87% compared to the lowest ones.Conclusion: The correct management of soil fertility, improvement, and maintenance of soil fertility in modern agricultural systems will provide the nutrients needed by the plant and thus enhance the yield. Therefore, in recent years, many studies have been conducted on biological fertilizers. Mycorrhizal fungi are essential factors in the stable plant-soil system, which coexists with more than 85% of plants. Drought stress is one of the most influential environmental factors in plant growth and causes morphological, physiological, and metabolic changes. In addition, biofertilizers increase plant access to nutrients and produce and direct hormones involved in the growth of the root environment. They also increase stress tolerance and enhance yield. Considering the arid and semi-arid conditions of the country and the increase in demand for medicinal plants and Satureja bachtiarica spices, it is recommended to stop irrigation at the 50% flowering stage and use Azotobacter, Azospirillium, and Pseudomonas biofertilizers to obtain the maximum yield of leaves, flowering branches, and essential oil.
Agriculture and horticulture
Mohammad Hadi Shojaei Baghini; Mahdi Naghizadeh
Abstract
Background and objectives: Cumin (Cuminum cyminum L.) is one of the oldest aromatic plants in the world, known medicinally as the second domesticated medicinal plant in Iran. Drought stress, as oxidative stress, affects plant biochemical, physiological, and morphological responses. One of the ways to ...
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Background and objectives: Cumin (Cuminum cyminum L.) is one of the oldest aromatic plants in the world, known medicinally as the second domesticated medicinal plant in Iran. Drought stress, as oxidative stress, affects plant biochemical, physiological, and morphological responses. One of the ways to increase plants' resistance to environmental stress is to use plant growth regulators such as brassinosteroids and melatonin. These hormones increase plant performance in both stress and non-stress conditions. Plant growth regulators, by affecting plant metabolites, stimulating phytohormone biosynthesis, enhancing nutrient absorption, improving defense mechanisms, stimulating root growth, and improving gas exchange, contribute to plants' quantitative and qualitative performance in stress and non-stress conditions. Although some research shows that the use of plant growth regulators such as brassinosteroid and melatonin, which are of natural origin and compatible with the environment, has a significant effect on reducing adverse effects caused by environmental stresses; however, the combined use of these plant hormones is less reported. Therefore, in this research, the influence of the foliar application of brassinosteroid and melatonin on some physiological traits, including amount of malondialdehyde, hydrogen peroxide, electrolyte leakage, activity of antioxidant enzymes, accumulation of carbohydrates and proline, malondialdehyde, hydrogen peroxide as well as quantitative and qualitative yield of cumin was examined under water deficit conditions.Methodology: This research was conducted in the research greenhouse of the Faculty of Agriculture, Shahid Bahonar University, Kerman, Iran. A factorial experiment in a randomized complete block design with six replications was carried out in 2022. The experimental treatments included different levels of drought stress (100 % and 50 % field capacity; F.C.), melatonin (0 and 100 μM), and brassinosteroid (0 and 0.75 μM).Results: The results showed that water deficit increased the amount of malondialdehyde, hydrogen peroxide, electrolyte leakage, activity of antioxidant enzymes (peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) and superoxide dismutase (SOD)), as well as raised the accumulation of carbohydrates and proline in cumin plants. Indeed, brassinosteroids and melatonin significantly increased antioxidant enzyme activities and the concentrations of osmolytes. It also decreased the levels of malondialdehyde, hydrogen peroxide as well and electrolyte leakage in drought-stressed plants. Drought stress resulted in reduced cumin grain yield. In contrast, under these conditions, the percentage of cumin seed essential oil was increased. Foliar application of brassinosteroid and melatonin in stress and non-stress conditions improved cumin yield.Conclusion: Overall, it was concluded that the use of brassinosteroid and melatonin increased the resistance of cumin plants against drought stress by increasing the activity of antioxidant enzymes, increasing the accumulation of compatible osmolytes such as proline and carbohydrate, and maintaining the stability of the membrane and ultimately enhancing the yield of cumin seeds. The application of melatonin and brassinosteroid also affected the quality of the product and increased the percentage of cumin essential oil; however, the positive effects of brassinosteroid and melatonin were greater than those of brassinosteroid or melatonin applied separately.
Agriculture and horticulture
Babak Bahreininejad; Fatemeh Sefidkon; M.H. Lebaschy; Zahra Jaberalansar
Abstract
Background and objectives: Awareness of changes in medicinal plant yield quantity and quality over time is one of the most important goals in agricultural management. Satureja mutica is one of the valuable medicinal species growing in Iran. This study was conducted to evaluate the effects of different ...
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Background and objectives: Awareness of changes in medicinal plant yield quantity and quality over time is one of the most important goals in agricultural management. Satureja mutica is one of the valuable medicinal species growing in Iran. This study was conducted to evaluate the effects of different planting beds on changes in vegetative characteristics and essential oil components over the years of growth in S. mutica under rainfed conditions.Methodology: The experiment was conducted in the form of split plots in a randomized complete block design for three years (2018-2020) in the rainy conditions of Feridounshahr city, Isfahan province. Planting beds as the main plot included cow manure (30 tons per hectare), wheat straw (10 tons per hectare), and control (without cow manure and wheat straw). After the preparation of the field, the seedlings were planted at the bottom of the wells created at a distance of 50 x 50 cm from each other. During the growing season and at the time of 50% flowering, the studied traits including total plant dry weight, leaf and stem dry weight, plant height, crown diameter per plant, canopy area per plant, and in each square meter of land and the number of stems per plant were measured. For essential oil extraction, the flowering branches of the plants were harvested at the full flowering stage. After drying in the shade, the essential oil was extracted by the water distillation method. After determining the yield of essential oils based on the dry weight of the plant, the essential oils were analyzed and identified by gas chromatography, and gas chromatography was connected to a mass spectrometer in the phytochemistry laboratory of the Research Institute of Forests and Rangelands. Considering that the plant is several years old and measurements are carried out every year on fixed plots, the design analysis was done on divided plots at the time of implementation. The SAS computer program was used to perform statistical calculations, and the LSD test was applied to compare the means. For essential oil extraction, the flowering branch of the plant was harvested at the full flowering stage. After drying in the shade, the essential oil was extracted by the water distillation method. After determining the yield of essential oils based on the dry weight of the plant, the essential oils were analyzed and identified by gas chromatography, and gas chromatography was connected to a mass spectrometer in the phytochemistry laboratory of the Research Institute of Forests and Pastures. The SAS computer program was used to perform statistical calculations, and the LSD test was used to compare the means.Results: The variance analysis of the data showed that the effects of bed, year, and their interaction effects on the measured traits were significant in many cases. Results showed that the highest values of plant height, crown diameter, canopy area, and number of stems per plant in the first year were seen in manure treatment. In the last year, they were in control. The highest rates of total dry weight, leaf dry weight, essential oil yield, and essential oil percentage were observed in control in the last year. These rates were 1427, 891, 42 kg ha-1, and 4.67%, respectively. The main essential oil components are thymol, carvacrol, p-cymene, and gamma-terpinene. These essential oil components are affected by the planting bed and the growth year. So in the case of p-cymene, the highest amount obtained in the first year was in the straw treatment. The highest amounts of gamma-terpinene were observed in all three planting bed treatments in the last year of growth. S. mutica had significant amounts of thymol, and the trend of changes among planting bed treatments and during growing years was very small. The highest amounts of carvacrol were observed in straw treatment and animal manure in the second year of growth. The results of the correlation coefficients showed that the most vital traits affecting essential oil yield were total dry weight, leaf and stem, and essential oil percentage. Thymol and p-cymene were inversely correlated with carvacrol and gamma-terpinene.Conclusion: On the whole, to produce S. mutica under rainfed conditions similar to this study, manure or straw could affect yield and essential oil over the first and second years; however, in the third year, this effect diminished, and control treatment was superior to straw and manure treatments.
Agriculture and horticulture
Afshin Tavakoli; Samaneh Asadi-Sanam; Arash Roozbahani
Abstract
Background and objectives: In producing medicinal plants, it is critical to use plants with a high percentage of active ingredients and consume low amounts of water. Thymus daenensis Celak is a tolerant Thymus species for rainfed cultivation. In addition, using complementary irrigation regimes and applying ...
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Background and objectives: In producing medicinal plants, it is critical to use plants with a high percentage of active ingredients and consume low amounts of water. Thymus daenensis Celak is a tolerant Thymus species for rainfed cultivation. In addition, using complementary irrigation regimes and applying anti-stress compounds at critical stages of plant growth are suitable programs for sustainable production and optimal water consumption under dry farming conditions. For this purpose, this experiment was to evaluate the effect of different complementary irrigation regimes along with sodium nitroprusside (SNP) as a nitric oxide donor, kaolin, and potassium spraying on yield and some biochemical characteristics of T. daenensis under rainfed conditions.Methodology: This experiment was designed and implemented as a split plot based on a randomized complete blocks design with three replications in the research field of the Research Institute of Forests and Rangelands-Homand Rangelands Research Station (Damavand) for three years (2017-2019 crop years). The experimental treatments included complementary irrigation as the main factor at three levels: control (no irrigation), one and two complementary irrigation, and spraying of stress-modulating substances as a secondary factor with three compounds of SNP (200 µM), kaolin (5%) and potassium (75 kg/ha from a potassium sulfate source). Cultivation was indirect and through seedlings. To prepare seedlings, the seeds were planted in the cultivation trays in the greenhouse at the end of September. After growing in the greenhouse, the seedlings (8-10 leaves) were transferred to the field in November with rain monitoring. Complementary irrigation and different foliar spraying treatments were done twice in the pre-flowering and 10 % flowering stages. Treatments were applied in the third year of plant growth to increase economic yield. After applying the treatments, the plant's flowering branch was sampled to measure malondialdehyde (MDA). After measuring the morphological characteristics (plant height and canopy diameter) in the full flowering stage, plant shoots were harvested to determine the dry matter yield per square meter and hectare. Percentage and yield of essential oil, total phenol, total flavonoids, and antioxidant capacity were also determined.Results: The results showed that increasing the number of complementary irrigations increased the crown diameter, plant height, and dry matter yield per plant and hectare. Kaolin treatment under two complementary irrigation regimes had the highest height (31.6 cm), and the control treatment under no irrigation had the lowest height (19.3 cm). Also, using kaolin and two complementary irrigations showed the highest dry matter yield per m2 (77.2 grams) and per hectare (771.4 kg). In addition, MDA content was lower in the double complementary irrigation treatment with kaolin foliar spraying (1.22 μmol/g of fresh weight). Foliar spraying of kaolin, potassium, and SNP under rainfed conditions (without irrigation) increased the amount of essential oil (by 1.83, 1.67, and 1.6 percent, respectively) compared to the control treatment (1.4 percent). In contrast, the maximum essential oil yield per hectare was related to the double complementary irrigation regime with potassium foliar spraying (10.6 kg/ha). Foliar spraying with potassium in the regimes of without irrigation (rainfed) and one-time complementary irrigation had the highest content of total phenols and flavonoids, respectively. The highest antioxidant capacity was obtained without irrigation and foliar spraying (control).Conclusion: This experiment showed that complementary irrigation increased dry matter yield per plant and hectare. On the other hand, foliar spraying with anti-stress compounds, especially kaolin, and potassium, along with complementary irrigation, increased essential oil yield per hectare. In general, based on the results of this experiment, it is suggested to use complementary irrigation regimes according to the available water sources. In addition, it is suggested to use kaolin or potassium foliar application under rainfed conditions for T. daenensis.
Agriculture and horticulture
J. Hashempour; S. Asadi-Sanam; M. Mirza; M. Ghanbari Jahromi
Abstract
Background and objectives: Purple coneflower (Echinacea purpurea L.) is one of the most wellknown medicinal plant species with high economic value worldwide. In Iran, this species' roots and shoots are used in herbal medicines. Many types of phytomedicine are commercially produced from Echinacea aerial ...
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Background and objectives: Purple coneflower (Echinacea purpurea L.) is one of the most wellknown medicinal plant species with high economic value worldwide. In Iran, this species' roots and shoots are used in herbal medicines. Many types of phytomedicine are commercially produced from Echinacea aerial portions for boosting the nonspecific immune system and treating the common cold. Environmental and health costs of chemical fertilizers have led researchers to meet plant nutritional needs using chemical, organic and biological fertilizers. The present study aimed to investigate the effects of organic and biological fertilizers on morphological traits, shoot and root dry matter, and essential oil percentage and yield in the leaves and stems of coneflower plants.Methodology: This experiment was conducted on a randomized complete block design with three replications at the Research Institute of Forests and Rangelands, Iran, in 2018-2019. Treatments included control, NPK (N50P25K25; N75P35K35 and N100P75K75 Kg.ha-1), manure (30, 60 and 90 ton.ha-1), vermicompost (5, 10, and 15 ton.ha-1), N50P25K25 fertilizer + 30 ton.ha-1 manure, N50P25K25 + 5 ton.ha-1 vermicompost, biological fertilizers including Glomus intraradaices + G. mosseae, Azospirillum + Pseudomonas, Thiobacillus + 5 ton.ha-1 vermicompost and Thiobacillus + 250 Kg.ha-1 of sulfur (S). Before applying fertilizer treatments, a soil analysis was done. After applying fertilizer treatments, the physical and chemical properties of the soil were also determined. The treatments were selected based on the fertilizer requirements of the plant as well as soil test results. Parameters such as plant height, leaf, stem, and flower numbers, root penetration depth, root volume, leaf, stem, root, and flower dry matter, leaf, stem, and flower essential oil, and essential oil yield of leaves, stems, and flowers were evaluated. At the full flowering stage, samples were taken from aerial segments of plants in all treatment groups. After shade-drying, the samples through a Clevenger-type apparatus were hydro-distillated to obtain the essential oil. The oil percentage, as well as yield, was calculated based on the dry weight.Results: The results showed that the highest leaf and stem dry matter was observed in the 15-ton.ha-1 vermicompost treatment. A 5-ton.ha-1 vermicompost treated with NPK fertilizers displayed the highest flower dry matter. On the other hand, the highest root dry matter was obtained in the treatment with 30 tons.ha-1 manure + NPK fertilizers. The highest flower essential oils yield was obtained in ton.ha-1 manure + NPK fertilizers. The highest leaf + stem oil yields were found at the flowering stage in 15 tons.ha-1 vermicompost. Also, NPK treatment + 30 tons.ha-1 of manure resulted in the highest yield of flower essential oil. 15-ton.ha-1 vermicompost treatment yielded the highest stem and leaf essential oil yield. Only the organic fertilizer group (CM vs. V5) and the biofertilizer group (GM and GI vs. T) showed an increase in flower essential oil yield compared to the other nutritional treatments. In the leaf+stem essential oil yield results, all comparisons between treatment groups showed a significant effect, except for the organic fertilizer group (CM vs. V5). Compared to the NPK group, the biofertilizer and organic fertilizer group yielded the highest leaf+stem essential oil yield.Conclusion: It was concluded that biological fertilizers treatment combined with organic fertilizers could be a suitable alternative to chemicals in the sustainable production of this valuable medicinal plant. These findings suggested that biofertilizers and organic fertilizers can benefit Echinacea purpurea cultivation because, when combined, they enhance the essential oil percentage and yield.
