Research Article
Medicinal Plants
Hoda Sajedimehr; Mahya Sajedimehr; Majid Azizi
Abstract
IntroductionMedicinal plants with a high level of antioxidant activity are of great importance due to their effect on a wide range of diseases such as diabetes, inflammatory diseases, Parkinson's, Alzheimer's, cardiovascular diseases, blood pressure and other diseases caused by oxidative stress. Therefore, ...
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IntroductionMedicinal plants with a high level of antioxidant activity are of great importance due to their effect on a wide range of diseases such as diabetes, inflammatory diseases, Parkinson's, Alzheimer's, cardiovascular diseases, blood pressure and other diseases caused by oxidative stress. Therefore, studying medicinal plants and extracting and identifying chemical properties and effective compounds in medicinal plants emphasizes the necessity of learning and using medicinal plants. Iranian shallot plant with the scientific name Allium hirtifolium is a species of the onion family (Alliaceae) and is one of the largest genera of the monocot group. Shallot plant is an important horticultural product that has been known and used as a vegetable, spice and medicinal plant since ancient times due to its useful properties. In this genus, there are economically important species such as: onions, garlic, shallots, chives and leeks. Germination and sprouting are one of the most important phenological stages (life cycle) of the plant. Having enough information about the phenological cycle of the plant leads to better management of the different stages of this cycle, which determines the degree of success of agricultural systems. Seedling germination and growth in the early stages are strongly influenced and controlled by environmental factors, especially temperature, soil moisture and seed quality (germination and seedling strength) and internal factors (growth regulators) such as Gibberellin and Abscisic acid hormones.In order to speed up the germination of seeds and eliminate seed dormancy so that germination can happen faster, there are different methods. One of these methods is mechanical or chemical scratching. The aim of this research is to present a precise and scientific description for the failure of Iranian shallot medicinal plant seed dormancy (Allium hirtifolium) and improvement in the acceleration of germination, considering the different characteristics in three populations of Iranian shallot seeds. Also, to increase the quality and accuracy in this research, a scanning electron microscope was also used to accurately determine the surface changes of the seeds before the acid-washing treatment with sulfuric acid and after the acid-washing treatment with sulfuric acid. In the previous research that has been carried out on Iranian shallot seeds, the simultaneous examination of different temperatures and different times of acid washing by sulfuric acid in a precise manner and with several populations that have different genotypes, as well as the use of Scanning Electron Microscopy (SEM) has not been done.Materials and methodsThe study was done to investigate the effect of different degrees of temperature, and different times of sulfuric acid for acid washing on the improvement of germination of three populations of Iranian shallot seeds (Allium hirtifolium). The effect of four different temperatures (5, 10, 15 and 20 degrees Celsius) inside the Germinator device and four different times of acid washing with sulfuric acid (0, 5, 10, 15 minutes) on germination and micromorphological characteristics of three populations of shallot plant (Feridon Shahr, Tiran and Khansar) was investigated. On the other hand, a scanning electron microscope (SEM) with different degrees of magnification was used for the effect of sulfuric acid treatment on the surface of the seed coat. The experiment was conducted as a factorial, in the form of a completely randomized design with four replications. At the end of the experiment, traits such as germination percentage, average germination time, germination speed, root length and shoot length were evaluated. Also, traits such as diameter, length, volume and weight of seeds in three populations of shallot were also analyzed statistically.Conclusion and discussionThe results of electron microscopy showed that in all three populations of Iranian shallot seeds, the seed coat, after using the acid washing treatment with sulfuric acid for 15 minutes, underwent noticeable and significant changes compared to the control seeds. The surface of the seed is destroyed by sulfuric acid and the surface of the seed does not have its natural ornamentation and protrusions compared to the control. Also, the effect of temperature, duration of acid washing and seed population on germination percentage, germination speed, average germination duration, seedling root length and seedling length was significant at the 1% probability level (p≤0.01). The population of Fereydoun Shahr has the highest germination percentage (69.16 percent), germination speed 3.7 (number of seeds per day) and average duration of germination 9.64 (number of seeds per day) at a temperature of 5 degrees Celsius and acid washing time of 15 minutes. The maximum shoot length and root length were 19.7 and 8.81 (mm) in the Tiran population with a temperature of 20 degrees Celsius and a 15-minute acid washing time, and in the Khansar population with a temperature of 20 degrees Celsius and time of 5 minutes acid washing respectively. The results show that, according to the dormancy of the seeds and their need for cold, the best temperature for shallot seed germination is 5 degrees Celsius with 15 minutes of acid washing by sulfuric acid. Diversity in shallot plant populations has a significant effect on the performance of this plant in improving seed germination.AcknowledgeWe thank Ferdowsi University of Mashhad and the Isfahan University of Technology.Keywords: shallot diversity (seed morphology), stratification, seed scarification, germination, scanning electron microscope (SEM)
Research Article
Growing vegetables
Nasrin Farhadi; Mojgan Abdeshahian; Samane Mottagi
Abstract
IntroductionCurrently, salinity stress is one of the most important challenges in the agriculture and is the main growth limiting factor of many plant species. Saline stress adversely affects the plant's physiological and biochemical process which leads to a considerable reduction of plant growth and ...
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IntroductionCurrently, salinity stress is one of the most important challenges in the agriculture and is the main growth limiting factor of many plant species. Saline stress adversely affects the plant's physiological and biochemical process which leads to a considerable reduction of plant growth and yield. Shallot (Allium hirtifolium Boiss.) is a perennial plant from the Alliaceae family, which is one of the native and valuable plants of Iran and wildly grows in the slopes of the Zagros Mountain range. The nutritional and medicinal value of shallots is due to the presence of sulfur compounds, especially allicin in the bulbs. The present study was conducted to investigating the effect of foliar application of salicylic acid on the changes of growth, physiological and biochemical traits of shallot under different levels of salinity stress in factorial design based on a completely randomized design with three replications. The investigated treatments were four levels of salinity (0, 30, 60 and 90 mM NaCl) and four levels of salicylic acid (0, 1, 1.5 and 2 mM). Distilled water (control) and salicylic acid (1, 1.5 and 2 mM) were foliar sprayed on the whole plants at 4, 6 and 8 weeks after sowing date. At the end of the growing season (beginning of yellowing of the leaves of the plants), growth, physiological and biochemical traits were evaluated. Evaluation of lipid peroxidation, osmolality compounds and activity of antioxidant enzymes was carried out in the leaves of treated plants and the amount of pyrovat and allicin was measured in harvested shallot bulbs.Results and discussion Various abiotic stresses restrict plant productivity, and many efforts have been done to reduce plant growth inhibition by alleviating the disorder’s effects of these stresses. Exogenous application of plant growth regulators has been reported as an economic procedure to improve plant resistance to environmental stresses. It has been previously reported that salicylic acid as a signaling molecule alleviated the adverse effect of different stress condition. In this experiment, shallot resistance to saline condition was enhanced by the foliar spray of salicylic acid. The results showed a significant link between salicylic acid treatment and improvement of bulb biomass under saline conditions. Lipid peroxidation regards to accumulation of malondialdehyde and hydrogen peroxide increased with increasing the salinity intensity. Also, saline stress significantly enhanced the proline and glycine betaine content in stressed plants of shallot. The plant antioxidant activity induced under stress condition by increased the total phenol content as well as the activity of catalase, peroxidase, ascorbate peroxidase and superoxide dismutase enzymes. The pyrovat and allicin content of shallot bulb was increased with increasing salinity stress. The decreased in the photosynthetic pigments (total chlorophyll and carotenoids) led to a decrease in plant growth with the intensifying of stress level. So that the lowest leaf area, fresh and dry weight of bulbs were obtained in severe salinity stressed plants (90 mM NaCl). Foliar application of salicylic acid through increasing the antioxidant compounds (total phenol, pyrovat and allicin) and the activity of antioxidant enzymes (CAT, POX, APX and SOD) limited the of hydrogen peroxide accumulation and lipid peroxidation. The induced accumulated osmolyte compounds proline and glycine betaine was decreased in treated plant with salicylic acid. The treatment of salicylic acid considerably improved the chlorophyll and carotenoids content especially in salinity stressed plants. So that the applied of salicylic acid, especially at concentration of 2 mM, reduced the harmful effects of salinity stress on plant growth and bulb yield by increasing the photosynthesis pigments and consequently photosynthesis efficiency. Also increased growth in the treated plants with salicylic acid has been attributed to changes in the concentration of plant hormones, especially auxins and cytokinins (the most important plant growth stimulating hormones). Nevertheless, the growth reactions of treated plants to salicylic acid are different depending on the used concentration, the plant species and the growth stage at the treatment time.ConclusionIn the several literatures the salicylic acid effects on plant growth enhancement under unfavorable environmental condition attributed to salicylic acid-induced changes in plant biochemical and physiological processes. Based on the obtained results, the salinity resistance of the shallot plant in response to salicylic acid is related to the increased antioxidant capacity of the stressed plants, which leads to the improvement of the photosynthetic pigments, and consequently plant growth and bulb biomass under saline condition. Although the present study was performed in the glass greenhouse, the obtained finding showed that salicylic acid application could also be a promising treatment for improving salinity tolerance of A. hirtifolium under field conditions.
Research Article
Medicinal Plants
Soroush Tafakhori; Vahid Akbarpour; Mohammad Kazem Souri
Abstract
Introduction
Basil (Ocimum basilicum L.), a warm-season herbaceous plant from the Lamiaceae family, is a valuable medicinal and culinary herb widely used in pharmaceutical, cosmetic, and food industries. Its aromatic leaves and mucilaginous seeds, beneficial for soothing sore throats, make it a significant ...
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Introduction
Basil (Ocimum basilicum L.), a warm-season herbaceous plant from the Lamiaceae family, is a valuable medicinal and culinary herb widely used in pharmaceutical, cosmetic, and food industries. Its aromatic leaves and mucilaginous seeds, beneficial for soothing sore throats, make it a significant crop in West Asia and the Middle East. As global populations grow, greenhouse and urban farming, such as vertical farming systems, have gained prominence to ensure year-round production (Massa, 2006). However, basil’s growth and productivity are often limited during low-light conditions, particularly in colder seasons. To address this, artificial lighting, particularly light-emitting diodes (LEDs), has emerged as a powerful tool due to their ability to deliver specific wavelengths, high photoelectric conversion efficiency, and optimal photosynthetically active radiation (PAR) efficiency (80–100%) (Darko et al., 2014). LEDs allow precise control over light quality and intensity, enhancing plant biomass and secondary metabolite production. Additionally, ascorbic acid, a potent antioxidant, plays a critical role in detoxifying reactive oxygen species (ROS) and improving plant growth under stress conditions (Shigeoka et al., 2002). Previous studies have shown that specific light spectra, particularly red and blue combinations, enhance terpenoid and phenolic content in basil (Rihan et al., 2020; Rafiei et al., 2023). Similarly, foliar application of ascorbic acid has been reported to improve growth and mitigate environmental stresses in various plants (Yadollahi et al., 2016; Esmailpour et al., 2023). This study investigates the combined effects of LED light spectra and ascorbic acid foliar application on the morphophysiological and phytochemical traits of basil under controlled conditions, aiming to optimize its production in low-light environments.
Materials and Methods
The experiment was conducted in the summer of 2024 at the Horticulture Laboratory of the University of Agricultural Sciences and Natural Resources, Sari, Iran. A split-plot design based on a randomized complete block with three replications was employed. The main factor consisted of four LED light treatments: three blue-to-red ratios (75:25 [BBBR], 50:50 [BBRR], 25:75 [BRRR]) and full-spectrum white light (FFFF). Red light was set at 660 nm, and blue light at 440 nm, with a photoperiod of 16 hours light and 8 hours darkness daily. The sub-factor included two levels of ascorbic acid foliar application (0.5 g/L weekly and no application). Basil seeds were sown in plastic pots filled with a 1:1 mixture of perlite and cocopeat and fertilized using Hoagland’s solution via fertigation. Morphophysiological traits, including stem diameter, number of lateral branches, leaf count, fresh and dry shoot weight, root fresh and dry weight, and root volume, were measured. Phytochemical traits, such as antioxidant activity (DPPH method, measured at 517 nm), total phenolic content (Folin-Ciocalteu method, measured at 765 nm), and flavonoid content (aluminum chloride method, measured at 415 nm), were assessed using a spectrophotometer (UV-1800PC, Shimadzu, Japan). Data were analyzed using analysis of variance (ANOVA), and means were compared using appropriate statistical tests.
Results and Discussion
The results demonstrated that the red-blue (75:25) light treatment significantly enhanced several morphophysiological traits compared to full-spectrum light, increasing stem diameter by 8%, lateral branches by 26%, leaf count by 15%, fresh leaf weight by 39%, and dry shoot weight by 25%. Foliar application of ascorbic acid further amplified these traits, with increases of 23%, 21%, 20%, 44%, and 31%, respectively. The combination of red-blue (75:25) light and ascorbic acid resulted in the highest stem height, root dry weight, and root volume, indicating a synergistic effect. These findings align with previous research showing that red light promotes stem elongation and biomass accumulation through gibberellin synthesis, while blue light regulates cellular expansion via cryptochromes (Hosseini et al., 2019; Kaiser et al., 2019). Ascorbic acid likely enhanced growth by acting as a coenzyme in photosynthesis and hormone biosynthesis, increasing carbohydrate production and nutrient uptake (Barkosky & Einhellig, 2003). For phytochemical traits, the red-blue (50:50) light without ascorbic acid yielded the highest antioxidant activity, suggesting that balanced light spectra stimulate defense mechanisms. The red-blue (75:25) light increased phenolic content by 12% and flavonoid content by 28% compared to full-spectrum light, consistent with studies showing that blue light enhances phenylpropanoid biosynthesis via phenylalanine ammonia-lyase (PAL) activation (Rafiei et al., 2023). However, ascorbic acid did not significantly increase flavonoid content, possibly due to metabolic saturation or suppression of defense responses at high antioxidant levels (Azoz et al., 2016). These results highlight the importance of tailored light spectra and nutritional interventions for optimizing basil’s growth and secondary metabolite production.
Conclusion
This study confirms that LED light spectra, particularly the red-blue (75:25) combination, significantly improve basil’s morphophysiological traits, including stem diameter, leaf count, and biomass, under low-light conditions. Foliar application of ascorbic acid enhances these effects, promoting root development and overall plant growth. While specific light spectra alone can boost antioxidant activity and phenolic content, ascorbic acid’s influence is more pronounced on growth than on flavonoid accumulation. These findings provide a practical framework for optimizing basil production in controlled environments, such as greenhouses and vertical farms, by integrating light quality management with ascorbic acid supplementation. This approach offers a cost-effective strategy to enhance both the quantity and quality of basil, supporting sustainable agricultural practices.
Research Article
Growing vegetables
Elnaz SoleimanyFard; Kambiz Mashayekhi; s.j Mousavizadeh; Mehdi Zarei
Abstract
Introduction
Melon (Cucumis melo L., Cucurbitaceae family) is an important commercial fruit crop that is extensively grown throughout the world due to its generally very good adaptation to climate and soil. The quality of melon fruits represents a combination of a wide range of physical characteristics ...
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Introduction
Melon (Cucumis melo L., Cucurbitaceae family) is an important commercial fruit crop that is extensively grown throughout the world due to its generally very good adaptation to climate and soil. The quality of melon fruits represents a combination of a wide range of physical characteristics (fruit size, shape, texture, firmness, etc.) and chemical compositions (acidity, sugars, vitamins, phenolic compounds, etc.), which are very important for consumers acceptability and marketability. On the other side, high-quality fruit must be achieved in the field because after harvesting time all fruit attributes can only be preserved, not improved. Hence, harvesting time plays an essential role in determining quality and marketability as well as storage life of melon fruits. Moreover, the accurate determinations of harvesting time and ripening stages of melon fruit have widespread application to improve management of it. Despite the increasing consumption and the cultivation of various melon accessions in different regions of Iran, the physical characteristics and chemical compositions of some fruit melon accessions (particularly lesser-known accessions) during fruit ripening have not yet been evaluated in detail. With this background, the specific objectives of study were, primarily, to monitor and compare the changes of physicochemical traits, total phenolics and antioxidant activity of two Iranian melon accessions (‘Chaghercheh’ and ‘Zamcheh’) during the ripening process and, secondly, to determine the optimal harvesting time to achieve maximum fruit quality and marketability.
Materials and Methods
In order to evaluate the influence of ripening process on quantitative and qualitative fruit properties of two lesser-known melon accessions (‘Chaghercheh’ and ‘Zamcheh’) have grown in Gonbad Kavous, the experiment was conducted according to factorial based on completely randomized design with 4 replicates (five fruits per replication) during two years (2023-2024). The developing fruits were hand-harvested at five different developing stages from 10 days after fruit set up to fruit ripening (namely, 10, 20, 30, 40 and 50 days after fruit set) during the months of June and July. Data of two years were combined and analyzed by Statistical Analysis System (SAS) software using analysis of variance and differences among means were determined for significance at P < 0.05 using Tukey’s test. Pearson correlation analysis was performed to identify the relationship between the different physical and chemical characteristics.
Results and Discussion
The findings of this experiment confirmed that there were significant differences among the different harvest times in all measured factors for both accessions. The fresh weight and dimensions of fruit, thickness and percentage of pulp increased throughout fruit ripening and reached to the maximum values at last harvesting stage, while fruit firmness, peel thickness, percentages of peel and seed showed a descending trend in the same period. At full maturation stage, the both melon accessions exhibited the highest total soluble solids and pH, along with the lowest titratable acidity, resulting in the highest maturity index. As the ripening proceeded, levels of ascorbic acid, total phenolics and antioxidant activity incremented, and reaching the peaks on 30th day after fruit set, but afterward mentioned factors reduced dramatically until the end of the harvesting period. Also, significant differences of all measured parameters were statistically detected among two melon accessions. At full maturation stage, the fruit fresh weight, fruit firmness, total soluble solids, titratable acidity, ascorbic acid, total phenolics and antioxidant activity were varied from 2438.12 (‘Zamcheh’) to 2941.17 g (‘Chaghercheh’), 14.02 (‘Zamcheh’) to 20.66 N (‘Chaghercheh’), 13.17 (‘Chaghercheh’) to 15.23 °Brix (‘Zamcheh’), 0.59 (‘Zamcheh’) to 0.79 mg.100g-1 FW (‘Chaghercheh’), 17.80 (‘Zamcheh’) to 19.47 mg.100g-1 FW (‘Chaghercheh’), 21.34 (‘Zamcheh’) to 22.48 mg.100g-1 FW (‘Chaghercheh’) and 22.26 (‘Zamcheh’) to 24.08% (‘Chaghercheh’), respectively. Also, the antioxidant activity was positively correlated with total phenolics (r = 0.936) and ascorbic acid (r = 0.869).
Conclusions
Overall, the data of this study revealed the degree of maturity and the variety are main parameters controlling the quantitative and qualitative characteristics of melon fruit. The both accessions showed identical evolution trends throughout their growth and development. The period between 40 and 50 days after fruit set seemed to be the most active time of fruit ripening in both accessions, which growers can maximize marketability, nutritional value and quality of melon fruit by choosing the ideal harvest. In general, the both accessions are potential source of bioactive compounds and antioxidant activity that can be regarded as an important nutrient for dietary and health of human.
Research Article
Growing vegetables
Fahimeh Ghaemizadeh; Farshad Dashti
Abstract
Introduction
Onion (Allium cepa L.) is a vegetable with great nutritional value. In the recent years, the cultivation of onion seedlings has expanded due to the rising production costs and limited water resources. The growth of high-quality seedlings is crucial for achieving optimal and high crop yield. ...
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Introduction
Onion (Allium cepa L.) is a vegetable with great nutritional value. In the recent years, the cultivation of onion seedlings has expanded due to the rising production costs and limited water resources. The growth of high-quality seedlings is crucial for achieving optimal and high crop yield. Light quality is a significant factor influencing seedling quality, as it markedly affects the morphological and photosynthetic responses of plants. Currently, LED lights are employed in growth chambers to enhance seedling development. Another important factor influencing seedling growth is the cell volume of the seedling tray. Larger cells offer a more suitable environment for the optimal growth of seedlings; however, increasing the volume of the seedling tray may impose spatial constraints for producers. The aim of this study is to evaluate the effect various tray cell volumes in combination with different light conditions to improve the growth and quality characteristics of onion (Allium cepa L.) seedlings.
Material and methods
To this end, an experiment was conducted in a factorial design comprising two levels of cell volume (28 cc and 18 cc) and three levels of light composition (75% red: 25% blue, 50% red: 50% blue, and 75% blue: 25% red), with three replications, using the Azar Shahr onion cultivar (red and long-day onion). Seed were cultured in the growing substrates (2 coco peat: 4 perlite). After the emergence of the first true leaf (with a leaf length of approximately 5 centimeters), the plants were transferred to a growth chamber equipped with LED lamps and subjected to light treatments for a duration of 45 days. Ultimately, after the seedlings were removed from the growth chamber, various growth parameters were measured, including seedling height, length of the longest true leaf, root length, Pesodostem diameter and length, fresh and dry weight, photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophyll, carotenoid), fv/fm, photosynthesis rate, stomatal conductance, sub-stomatal CO2 concentration, transpiration rate, total carbohydrate content, and total phenolic content. At the end of the experiment, data analysis was performed using SAS software (version: 9.1).
Results and discussion
According to the results, in the 18 cc cell compared to the 28 cc cell and at all light treatment, seedling length, length of the longest leaf, and Pesodostem length increased, and root length, fresh and dry weight decreased. However, in the 18cc cell, using a 75% red: 25% blue light treatment resulted in the highest quality seedlings with a length of 25.5 cm, Pesodostem diameter (2.13 mm), Pesodostem length (3.4 mm), and dry weight (34 mg). Although at all light levels, cell volume reduction resulted in a decrease in photosynthetic pigments (amount of chlorophyll a, chlorophyll b, total chlorophyll, carotenoid), FV/FM, a decrease in substomatal carbon dioxide, photosynthetic rate, soluble carbohydrates, and phenol content. However, the highest levels of these parameters were observed in the small cell, in the 75% red: 25% blue light treatment. At all it seems that, using a smaller cell volume reduces the root's access to oxygen, water, and nutrients, leading to reduced root growth and some seedling quality parameters. Also, reducing the cell volume also increases the number of plants per tray. This increased density reduces the seedling's access to the appropriate light treatment. However, using an appropriate light treatment can improve growth and physiological parameters. Overall, in the smaller cell with high planting density, the use of the 75% red: 25% blue light combination can lead to improved growth and increased seedling quality. Under red light treatment, plants have smaller stomata and can more effectively control the process of stomatal opening and closing. In this light, in addition to the entry of carbon dioxide, a smaller amount of water is lost, which also increases water consumption efficiency. Therefore, combining red and blue light can offset the negative effects of red and blue light and increase the rate of photosynthesis. However, the response of different plant species to different ratios of red to blue light may vary.
Conclusion
In conclusion, our findings indicate that utilizing trays with smaller cell volumes (which allows for higher planting densities) can be economically beneficial and space-efficient. However, to ensure optimal onion seedling quality, it is crucial to implement a light composition of 75% red and 25% blue during the growth period.
Research Article
Growing vegetables
abdulsatar darabi; zahr Abbasi Abbasi
Abstract
Introduction
Onion is one of the most important vegetables in Iran and is cultivated in 51.499 hectares. The cultivated area of this crop in the short-day southern regions is 25.964 hectares, which is equivalent to more than 50% of the cultivated onion area in Iran. Commercial short-day onion cultivars ...
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Introduction
Onion is one of the most important vegetables in Iran and is cultivated in 51.499 hectares. The cultivated area of this crop in the short-day southern regions is 25.964 hectares, which is equivalent to more than 50% of the cultivated onion area in Iran. Commercial short-day onion cultivars are cultivated in most of these regions, so that large amount of currency is expensed to import short-day onion seed. In addition, the increase in the currency rate in recent years has increased the cost of onion production in short-day southern regions. Therefore, it is very important to produce and introduce short-day onion cultivars. This research was conducted to produce half-sib families through open pollination among nine superior onion cultivars. The best half-sib families were selected in terms of bulb yield and storability.
Materials and methods
This project was carried out in Isfahan and Khuzestan during three crop years (2020-2023). During two crop years of 2020-2022, a polycross genetic design was carried out among nine short-day onion cultivars (Sahar, Paliz, Saba, Savanasweet, Goldeneye, Duster, Impriaterize, Primavera, and Texas Early Grano) in the Isfahan location (Dastgerd Agriculture Research station), and half-sib families were produced. The progenies of half-sib families along with their parents were evaluated in a randomized complete block design (RCBD) with 18 treatments and three replications in Khuzestan location (Behbahan Agriculture Research station) during the crop year of 2022-2023. Seeds were sown in the nursery in early October, and seedlings were transplanted (at the two- or three-leaf stage) in late September. The earliest bulb time was estimated using the bulb ratio and statistical technique of cusums. The studied traits included leaf number and height, bolting percentage, bulb yield, days to maturity, mean bulb weight, mean bulb diameter and height, skin number, total soluble solids, dry matter, and bulbstorage losses. Bulbs were harvested when 50-80% of the foliage top had fallen and collapsed. To calculate dry matter content of the bulb, 10 bulbs were randomly selected from each plot and their weight was determined. After drying complete samples in the oven (65 ̊C) and fixing weights (about 72 h), samples were weighed again, and dry matter was calculated. After harvesting and curing, bulbs were stored under uncontrolled storage conditions (no heating, cooling, or ventilation systems), and after 3 months, postharvest bulb storage losses were determined. The results were analyzed using SPSS v.26. software. Means of significant differences among treatments were determined at the 0.05 probability level using Duncan’s test. Correlation coefficients among traits were calculated using Pearson method.
Results and Discussion
Bulbing occurred in the studied genotypes in a photoperiod of less than 13 h; therefore, all progenies and their parents were short-day genotypes. Palize cultivar produced the highest yield. The difference in bulb yield among this cultivar and Sahar, Saba, Savana sweet, and Goldeneye cultivars and Saba and Texas Early Grano half-sib families was not significant. The doubling bulb was not observed in studied genotypes. The highest bulb dry matter percentage was found in Texas Early Grano cultivar. The decrease in the percentage of bulb dry matter in the Saba cultivar and Savanasweet half-sib families was not significant compared with the Texas Early Grano cultivar. The highest skin number was recorded in the Texas Early Grano cultivar. The decrease in the number of skins in Sahar, Primavera, and Saba cultivars was not significant as compared with that in Texas Early Grano cultivar. The lowest bulb storage losses were observed in Sahar cultivar. The differences in this trait among Paliz, Primavera, and Texas Early Grano cultivars and Paliz, Savanasweet, Duster, Primavera, and Texas Early Grano half-sib families were not significant in comparison to Sahar cultivar. The correlation coefficients among bulb yield with leaf number and height, mean bulb weight and diameter were positive and significant at 1% probability level. Differences in days to maturity were not significant in all genotypes; therefore, final progeny selection was made with emphasis on bulb yield and storage losses. According to these results and comparison of days to maturity ,yield and bulb storage losses in progenies half -sib with maternal parent and parents mean the half-sib, progenies of Saba, Daster, and Texas Early Granohalf- sib families were selected.
Conclusion
The results showed that Texas Early Grano, Saba, and Duster half-sib families with high bulb yields (from 65.18 to 68.29 t ha-1) and good storability (storage bulb losses from 11.79% to 15.41%) are promising genotypes for introducing as short-day indigenous onion cultivars.
Research Article
Medicinal Plants
Reza Azadi Gonbad; Nasrin Farhadi
Abstract
Introduction
Hydroponic systems have emerged as an advanced method for cultivating medicinal plants, offering precise control over environmental and nutritional factors to enhance the production of secondary metabolites. Chemical elicitors, such as salicylic acid (SA) and methyl jasmonate (MeJA), play ...
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Introduction
Hydroponic systems have emerged as an advanced method for cultivating medicinal plants, offering precise control over environmental and nutritional factors to enhance the production of secondary metabolites. Chemical elicitors, such as salicylic acid (SA) and methyl jasmonate (MeJA), play a key role in stimulating plant defense responses and increasing the synthesis of valuable phytochemical compounds. These compounds alleviate biotic and abiotic stress signals, triggering plant defense mechanisms and stimulating the biosynthesis of valuable secondary metabolites, including phenolics, flavonoids, and essential oils (Mehdizadeh and Moghaddam, 2023). Salvia officinalis L. (sage), a perennial aromatic plant from the Lamiaceae family, is known for its medicinal properties and rich content of bioactive compounds, including essential oils and phenolic derivatives. Recent studies have demonstrated that exogenous application of SA and MeJA can significantly influence plant growth and secondary metabolism. However, their effects are highly concentration-dependent and species-specific, necessitating further research to determine optimal dosages for different medicinal plants (Mohi-Ud-Din et al., 2025). While some studies have explored the individual effects of these elicitors, their synergistic interactions in hydroponically grown sage remain understudied (Jeyasri et al., 2023). This study investigates the synergistic effects of SA and MeJA foliar application on the growth, phytochemical composition, and antioxidant activity of sage in a hydroponic system.
Materials and Methods
This experiment was conducted as a factorial design based on a completely randomized design with three replications. Treatments included the foliar application of SA (0, 0.5, and 1 mM) and MeJA (0, 0.25, and 0.5 mM). Sage seeds were germinated under controlled conditions, and seedlings were transferred to a hydroponic system with a perlite-cocopeat (3:1, v/v) substrate. Plants were grown under natural light, with temperatures maintained at 20–30°C and relative humidity at 70–80%. Nutrient solutions were provided using Hoagland’s formula (EC 1.6 dS/m). Foliar treatments were applied at three growth stages: initial three-leaf, six-leaf, and flowering onset. Ten days after the final treatment, biomass, photosynthetic pigments, antioxidant enzyme activities (POX, APX, SOD), phenylalanine ammonia-lyase (PAL) activity, phenolic and flavonoid content, essential oil percentage, and antioxidant capacity (DPPH assay) were evaluated.
Results and Discussion
The experimental results demonstrated that the foliar application of salicylic acid and methyl jasmonate significantly influenced the growth, physiological traits, and phytochemical composition of hydroponically cultivated sage. The combined treatment of 0.5 mM SA and 0.25 mM MeJA produced the highest fresh (49.00 g) and dry (21.48 g) biomass, indicating a synergistic effect on plant growth. This enhancement can be attributed to the role of SA in promoting cell division and elongation, while MeJA at low concentrations stimulates metabolic activity without inducing excessive stress. However, higher MeJA concentrations (0.5 mM) exhibited inhibitory effects, likely due to the overactivation of defense mechanisms that divert energy away from growth-related processes. Photosynthetic pigments, including chlorophyll and carotenoids, were significantly influenced by the elicitor treatments. The combination of 1 mM SA and 0.25 mM MeJA resulted in the highest carotenoid content (2.34 mg g⁻¹ FW), suggesting that moderate elicitation enhances photosynthetic efficiency. Conversely, excessive MeJA (0.5 mM) led to a reduction in chlorophyll content, possibly due to accelerated senescence or oxidative stress. The application of SA and MeJA also induced a marked increase in antioxidant enzyme activities, including POX, SOD, and APX. Among the highest activities, POX was maximized in the combined treatment of 0.5 mM SA and 0.25 mM MeJA (20.49 U mg⁻¹ protein), while the highest APX (6.96 U mg⁻¹ protein) and SOD (1.95 U mg⁻¹ protein) activities were recorded in plants treated with 0.25 mM MeJA alone. These enzymes are critical for scavenging reactive oxygen species (ROS), which accumulate under elicitor-induced stress. The upregulation of these defense mechanisms not only protects cellular integrity but also stimulates the biosynthesis of secondary metabolites. A key finding was the significant increase in phenylalanine ammonia-lyase activity, a rate-limiting enzyme in the phenylpropanoid pathway. The highest PAL activity was observed in plants treated with 1 mM SA alone or in combination with 0.25 mM MeJA, correlating with elevated levels of total phenolics and flavonoids. Phenolic compounds, such as rosmarinic acid, are major bioactive constituents in sage, contributing to its antioxidant and antimicrobial properties. The increase in flavonoid content, particularly under the combination of 0.5–1 mM SA and 0.25 mM MeJA, further supports the role of these elicitors in activating secondary metabolic pathways. One of the most notable outcomes was the 39% increase in essential oil content under the 0.5 mM SA + 0.25 mM MeJA treatment. Essential oils in sage are synthesized via the terpenoid pathway, which appears to be strongly induced by these elicitors. The enhanced essential oil yield was accompanied by a significant improvement in antioxidant capacity, as evidenced by the DPPH radical scavenging assay. This suggests that the elicited plants not only produced higher quantities of bioactive compounds but also exhibited stronger free-radical quenching activity, which is valuable for medicinal and nutraceutical applications. These findings align with previous studies indicating that SA and MeJA act synergistically at optimal concentrations to enhance secondary metabolite production while maintaining plant growth. However, the negative effects of high MeJA levels (0.5 mM) underscore the importance of dosage optimization, as excessive elicitation can lead to phytotoxicity and metabolic imbalance.
Conclusion
This study demonstrated that the combined application of salicylic acid and methyl jasmonate in a hydroponic growth medium serves as a powerful tool for regulating growth and enhancing the production of secondary metabolites in sage plants (Salvia officinalis). A key finding was the identification of an optimal treatment combination (0.5-1 mM salicylic acid coupled with 0.25 mM methyl jasmonate), which synergistically increased biomass, essential oil content, and antioxidant activity. In contrast, higher concentrations of methyl jasmonate alone were found to inhibit growth. The implications of this research are significant, as it shows that by precisely modulating elicitor concentrations, the metabolic balance between growth and defense compound synthesis can be strategically managed to meet agricultural and pharmaceutical objectives.
Research Article
Postharvest physiology
Mohsen Mohammadi; Davood Hashemabadi; Behzad Kaviani
Abstract
Introduction
Cut tuberose flowers face challenges such as reduced vase life and postharvest quality deterioration. This problem is mainly caused by various factors such as dehydration, vascular blockage due to bacterial growth, ethylene accumulation and oxidative stress, which lead to a reduction in ...
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Introduction
Cut tuberose flowers face challenges such as reduced vase life and postharvest quality deterioration. This problem is mainly caused by various factors such as dehydration, vascular blockage due to bacterial growth, ethylene accumulation and oxidative stress, which lead to a reduction in the postharvest lifespan of flowers. To address these challenges, the use of chemical and natural compounds has been considered an effective method to extend postharvest longevity and maintain the quality of cut flowers. Aluminum sulfate helps to preserve the freshness of cut flowers by reducing microbial growth, improving water uptake and preventing vascular blockage. The use of aluminum sulfate in vase solutions has shown to increase of the postharvest lifespan in certain cut flowers, such as roses, gardenias and lisianthus. Plant essential oils (containing phenol), possess antioxidant, antibacterial and antifungal properties. They can inhibit microbial growth in vase solutions and prevent cellular damage caused by reactive oxygen species (ROS) or free radicals. The positive effects of certain essential oils on extending the vase life of some cut flowers, including gerberas, roses and alstroemerias, have been reported. Cobalt chloride prevents vascular blockage caused by bacterial agents in stems and maintains a high-water flow rate, leading to improved water uptake by cut flowers. This salt can also extend vase life by inhibiting ethylene production, preventing its accumulation and reducing respiration. The beneficial effect of cobalt chloride on increasing the vase life of some ornamental cut flowers, including roses, carnations, tuberoses, gladiolus and chrysanthemums, has been reported. 8-Hydroxyquinoline sulfate (8-HQS) is an inhibitor of ethylene production and reduces respiration rate. In cut flowers such as dendrobium, gerbera and gladiolus, 8-HQS extended the vase life by preventing microbial growth, reducing respiration rate and enhancing water absorption. This study aimed to investigate the effects of aluminum sulfate, Eryngium spp. essential oil, cobalt chloride and 8-HQS on the postharvest longevity of cut tuberose flowers (Polianthes tuberosa).
Materials and Methods
Cut tuberose (Polianthes tuberosa) flowers were obtained from a commercial producer in Tehran Province. To standardize the stem length, all flowers were recut at a 60 cm distance under water and immediately transported to the postharvest laboratory at the Faculty of Agriculture, Islamic Azad University, Rasht Branch, to prevent dehydration. Upon arrival, the flowers were placed in distilled water to maintain hydration. For the experiment, five cut flowers were placed in each 2-liter plastic vase and then treated with specific concentrations of the experimental factors. The study was conducted based on a completely randomized block design with three replications. The effects of different concentrations of aluminum sulfate (50, 100 and 150 mg/L), Eryngium essential oil (10, 20 and 40%), cobalt chloride (200, 300 and 400 mg/L) and 8-HQS (100, 200 and 400 mg/L) on cut flowers parameters such as vase life, water uptake, fresh weight loss, chlorophyll content, malondialdehyde (MDA) as an indicator of lipid peroxidation, bacterial colony count and antioxidant enzyme activity were evaluated. Thus, the present experiment consisted of 12 treatments, 3 replications and 5 flower stems per replication, totaling 36 experimental units (plots). Treatments were applied permanently, with each treatment prepared based on a 500 mL volume in the plastic vase. Data were subjected to analysis of variance (ANOVA) and means were compared by the LSD at P < 0.05 using the SAS ver. 9.2 software.
Results and Discussion
The results showed that treatment with aluminum sulfate significantly increased vase life and prevented fresh weight loss. Aluminum sulfate improved water uptake and preserved chlorophyll content, thereby enhancing the longevity of the flowers. Eryngium essential oil also had a positive effect on maintaining flower quality due to its antimicrobial and antioxidant properties. Results of the variance analysis showed that treatments with aluminum sulfate, Eryngium essential oil, cobalt chloride and 8-HQS significantly increased the vase life of tuberose cut flowers (P < 0.01). The effect of treatments was significant for most traits. The longest vase life (12 and 11.50 days) was observed in aluminum sulfate at 100 and 50 mg/L, respectively, while the control treatment had a vase life of only 8 days. The highest water uptake was observed in treatments with aluminum sulfate (100 mg/L), 8-HQS (200 mg/L) and Eryngium essential oil (10 mg/L). The control treatment had the highest bacterial population at the stem base (33 CFU/mL) and vase solution (73 CFU/mL). 8-HQS (400 mg/L) showed the lowest bacterial population at the stem base (4 CFU/mL). Just some treatments were selected for measurement of enzymes activity. Among the selected treatments, Eryngium essential oil (20 mg/L) exhibited the highest peroxidase (POD) enzyme activity, while the control treatment (0.07 µmol/g fresh weight) had the lowest. The control treatment (9.47 µmol/g fresh weight/min) showed the highest catalase (CAT) enzyme activity, while cobalt chloride (300 mg/L, 1.84 µmol/g fresh weight/min) had the lowest. Aluminum sulfate can partially reduce ethylene production and respiration rate in cut flowers. It primarily acts as an antimicrobial agent, indirectly extending vase life. Some studies suggest aluminum may moderately reduce lipid peroxidation in cell membranes. The aluminum ion may interact with cell walls, enhancing tissue rigidity and delaying wilting. Studies on roses, peonies and gladiolus confirmed that aluminum sulfate delays senescence by inhibiting microbial growth, preventing bacterial blockage and improving water uptake. Plant essential oils (e.g., in tuberose, chrysanthemum, gerbera, gladiolus and carnation) extend postharvest life due to their antimicrobial and antioxidant properties, reducing microbial load in vase solutions and ethylene production. 8-HQS, as a disinfectant, extended vase life in peonies, dendrobium and gladiolus by inhibiting bacteria, enhancing water uptake, delaying senescence, suppressing ethylene and reducing respiration rate. Increased POD activity in treated flowers indicates enhanced antioxidant defense, crucial for neutralizing free radicals and mitigating oxidative stress. Reduced CAT activity in treated tuberose flowers may result from lower ROS production, direct inhibition of enzyme activity, hormonal/metabolic signaling changes and delayed oxidative stress and senescence.
Conclusions
These findings suggest that the use of these compounds particularly aluminum sulfate at the concentration of 100 and 50 mg/L can be an effective method to improve the postharvest longevity and quality of cut tuberose flowers.
Short Article
Growing vegetables
Seyyed Hasan Mousavi; Nasrin Farhadi
Abstract
Introduction
Lettuce, with the scientific name Lactuca sativa L., is an annual, self-pollinating, cool-season vegetable belonging to the Asteraceae family. Its leaves are rich in antioxidant compounds, vitamins, and essential nutrients beneficial to human health. The genus Lactuca comprises over 100 ...
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Introduction
Lettuce, with the scientific name Lactuca sativa L., is an annual, self-pollinating, cool-season vegetable belonging to the Asteraceae family. Its leaves are rich in antioxidant compounds, vitamins, and essential nutrients beneficial to human health. The genus Lactuca comprises over 100 species, of which 20 belong to lettuce (Lactuca sativa). Numerous researchers have reported extensive diversity in morphological, biochemical, and genetic traits among different lettuce genotypes (Kumar et al., 2016; Dahal et al., 2021; Volpe et al., 2021; Asadi et al., 2022). According to FAO statistics, the production of various lettuce cultivars and lines has experienced a 118% growth over the past two decades, placing lettuce as the fifth most widely cultivated crop globally after corn, rice, potatoes, and tomatoes in terms of cultivated area (FAO, 2023). In Iran, lettuce is one of the most common leafy vegetables cultivated across various regions of the country. Alongside increasing market demand and the economic viability of lettuce production, diverse genotypes of different types—including leaf, stem, romaine, and iceberg—have been developed. Although romaine-type lettuces account for the majority of cultivated areas in Iran, in recent years, several well-adapted genotypes suitable for different regions in the north and south of the country have been introduced or are under development, receiving widespread acceptance. Evaluating and introducing suitable and adapted lettuce genotypes with desirable quantitative and qualitative traits, alongside indigenous Iranian lettuces, is of great importance (Mousavi et al., 2024). Accordingly, in the present study, several commercial lettuce genotypes of stem and leaf types were investigated under field conditions to identify superior cultivars and lines based on qualitative characteristics.
Materials and methods
The present study was conducted in both field and laboratory settings at the Greenhouse and Controlled Environment Research Institute, using a randomized complete block design with three replications. Seeds of lettuce cultivars including Batavia, Mignonette, Prize Head, Bull Red, Tango, French Red, Ice Green, Lines 4, 7 and 20 Roman were sown in 6×12-cell seedling trays containing a cocopeat : perlite (4:1) growing medium for seedling production. Seedlings at the 3-4 leaf stage were transplanted to the main cultivation beds in the field. Each cultivar was planted in 25-meter-long rows with 50 cm bed width, maintaining 50 cm spacing between plants within rows. Uniform cultivation practices including temperature control, humidity management, irrigation, and weed removal were applied to all plants. The drip irrigation system operated for one hour every two days. Following harvest, qualitative traits including pH, titratable acidity, total soluble solids, chlorophylls, carotenoids, total phenolic compounds, anthocyanin and antioxidant capacity were measured in the collected cultivars and lines. Statistical analysis was performed using SPSS software (version 21), with mean comparisons conducted using Duncan's test at the 5% probability level. Graphs were generated using Microsoft Excel (2013 version).
Results and discussion
According to the results of analysis variance, the qualitative traits studied were significantly influenced by lettuce cultivar type. The highest titratable acidity (1.52%), pH (5.38), and soluble solids content (6.83 Brix) were measured in Bull Red, Ice Green, and Line 20 Roman, respectively. The maximum chlorophyll a (13.36 mg g-1 fresh weight) and b (7.57 mg g-1 fresh weight) content were recorded in Mignonette and French Red cultivars, respectively. Line 20 Roman showed the highest carotenoid content, while Line 7 Roman exhibited the lowest value. Significant differences were observed among lettuce genotypes regarding total phenol and anthocyanin content. The highest total phenol content was recorded in Bull Red (616.17 mg g-1 fresh weight), followed by French Red (553.95 mg g-1 fresh weight). Bull Red and Mignonette cultivars contained the highest anthocyanin levels (3.768 and 1.823 mmol g-1 fresh weight, respectively). Regarding antioxidant capacity, Bull Red (97.75%), Line 20 Roman (93.41%), and Mignonette (92.74%) demonstrated the highest antioxidant activity. Variations in qualitative characteristics among different lettuce cultivars and lines are primarily influenced by genetic traits that determine flavor and taste differences among genotypes. The diversity in qualitative leaf traits (e.g., color and flavor) among lettuce cultivars has been attributed to underlying genetic differences (Volpe et al., 2021). Biosynthetic pathways and enzymes involved in the metabolism of various compounds—such as carotenoids and phenolic—vary significantly. Furthermore, their synthesis mechanisms, transporters, and metabolic pathways are genetically regulated (Dahal et al., 2021; Asadi et al., 2022).
Conclusion
Based on the assayed quality traits, Bull Red, Mignonette, French Red, and Line 20 Roman cultivars with desirable qualitative characteristics are recommended for lettuce cultivation and production.
Research Article
Medicinal Plants
zahra mahdavi; behrouz esmaielpour; rasoul azarmi
Abstract
Evaluation of morphophysiological and biochemical characteristics of Stevia rebaudiana Bertoni treated with proline nanoparticles and liquid fish waste fertilizer in salinity stress
Introduction
Stevia rebaudiana Bertoni is plant perennial medicinal of the Asteraceae (Compositae) family. Stevia plants ...
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Evaluation of morphophysiological and biochemical characteristics of Stevia rebaudiana Bertoni treated with proline nanoparticles and liquid fish waste fertilizer in salinity stress
Introduction
Stevia rebaudiana Bertoni is plant perennial medicinal of the Asteraceae (Compositae) family. Stevia plants contain many compounds with medicinal properties, importantly steviol glycosides (e.g., stevioside, steviolbioside, rebaudiosides A.E and dulcoside), in the leaves and shoots that are used as natural and useful sweeteners in the food industry. These sweeteners are 300 to 400 times sweeter than glucose and sucrose and calorie-free. Salinity stress is causes major constraints factor affects crop production in world . The adverse effects of salinity stress on plant growth can be related to factors e.g. induced osmotic stress and ionic imbalance. Ionic imbalance is due to high presence of sodiumand chloride. There is several strategies for reduce salt effects in plants that including have been used biofertilizers, organic fertilizers and nanoparticles. Nanoparticles (NPs) as one of the most important effective methods, to reduce salinity stress condition. Nano-materials are at a scale of 100 nm or less. Proline can be mentioned among nano-materials. Proline (Pro) is one of compatible solutes and cellular protector accumulated in response to abiotic stress. Accumulation of proline happens in plant during exposure to stress. The amount of this biosynthesis is insufficient, so it is applied externally to tolerance with the stress of this substance. Organic fertilizers reduce the harmful effects of chemical fertilizer and improve the chemical, biological structure of soils, leading to increased crop yield. waste reduction and especially fish waste (as one of the concerns of the world today) is one of the important strategies for environmental sustainability. Fish processing waste is rich in essential proteins, macro and micronutrients that casuses reduced salinity stress.
Method
Stevia seedlings were purchased from a medicinal plant greenhouse (zargiah) in Shiraz city and planted in 12 L pots. This study was conducted in a factorial experiment and based on a completely randomized design with four replications in the spring-summer of 2022. Planting bed includes containing a mixture of cocopeat and perlite .The plants were first irrigated with half-strength Hoagland’s solution and then irrigated with full-strength nutrient solution. The first factor was salinity stress at four levels (0, 30, 60, 90 mM NaCl) and the second factor salinity reducer at five levels (control, 15 and 30 mgL-1 glycine betaine without liquid fish waste fertilizer, 15 and 30 mgL-1 glycine betaine with 15% (v/v) liquid fish waste fertilizer). Then growth parameters, relative water content, a* and b* color and total phenol, hydrogen peroxide (H2O2), malondialdehyde (MDA), proline, and total carbohydrates were measured. Data were analyzed using SAS 9.1 software by analyzing the means using Duncan’s multiple range test, with a significant difference level at p < 0.05.
Results
Salinity stress significantly decreased plant growth traits. Salinity, increased proline and total phenols, MDA, H2O2, EL compared with the control. Fish waste fertilizer with proline nanoparticles increased morphological parameters, RWC, proline, phenols, sugar, and reduced EL, MDA, and H2O2. Salinity stress caused a 39% reduction in plant height, 50.24% in root fresh weight, 70.93% in root dry weight, 46.15% in relative water content, 55.93% in a*color, 51.16% in b*color, 39.44% in proline, 71.68% total carbohydrate, 42.7% by phenol and 73.33% by hydrogen peroxide by compared to the control. The application of 20 mg/L proline nanoparticles simultaneous with liquid fish waste fertilizer resulted in reduction a 31.7% by membrane electrolyte leakage, 56.66% by root sodium, and an increase of 78.23% proline, 72.98% by total carbohydrate, 71.42% root potassium, and 62.45% by root calcium under 90 mM salinity stress compared to the control treatment.
Conclusions
Results showed that salinity due to accumulation in Na+ and disruption to the absorption of essential nutrients especially N and K, negatively affected plant growth and yield and overall. Proline and fish waste bio- fertilizer with increase in potassium causes open of the stomata increase of photosynthesis and plant growth. Application of proline especially when used at a concentration of 20 (mg/l) and fish waste bio-fertilizer could be considered as a sustainable, for the mitigating of salinity stress effects in stevia plants and potentially other crops. Hence, proline nanoparticles with fish waste bio-fertilizer could be considered an effective method to apply on plants under different stress conditions to mitigate stress effects through a safe and environmentally friendly method.
Research Article
Ornamental plants
Mohammad Ahmadpour,; Azadeh Mousavi Bazaz; Ali Tehranifar
Abstract
Introduction
Water scarcity, along with growing population and global warming, forms a serious worldwide problem for desert countries such as Iran. Since the rainfall every year is limited, effective use of water resources is of utmost significance. Substitution of lawns with high-water-demand requirements, ...
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Introduction
Water scarcity, along with growing population and global warming, forms a serious worldwide problem for desert countries such as Iran. Since the rainfall every year is limited, effective use of water resources is of utmost significance. Substitution of lawns with high-water-demand requirements, by drought-resistant, native ground cover plants, is one of the key steps. lawns establish quickly, but are expensive to maintain with high watering reqirements, and hence are unsuitable for current climatic conditions. Previous studies have shown that sustainable management practices such as soil improvement, mulching, and advanced irrigation systems such as subsurface irrigation can reduce water consumption. Urban green spaces play an important role in enhancing environmental quality and public health, and drought-resistant ground covers can assist in the achievement of international green space standards. These plants improve soil health, minimize erosion, inhibit weeds, and require less upkeep than traditional lawns. The aim of this research was to examine the performance of different species of ground covers as alternatives to lawns for the purposes of improving the efficiency of water use and biodiversity in urban environments.
Materials and Methods
This August 2024 greenhouse experiment was conducted at Ferdowsi University of Mashhad (36°20′N, 59°39′) to compare responses to drought stress among selected groundcover species. Festuca arundinacea was sown at 12 g per pot, and Phyla nodiflora and Sedum acre were grown from uniform rooted cuttings. A completely randomized factorial design with four irrigation levels (20%, 40%, 60%, and 80% of field capacity) and three replications was used. Drought treatment started after full establishment for 75 days. Morphological traits (shoot height, root length, fresh and dry biomass) physiological, (relative water content, electrolyte leakage), and biochemical parameters (chlorophyll a and chlorophyll b) were measured at the end of the experiment. Relative water content (RWC) and Electrolyt leakage (EL) were measured using standard procedures, and pigment contents were measured by spectrophotometry. Daily water consumption was measured gravimetrically. Data were statistically examined using ANOVA and Duncan's multiple range test at a 5% significance level in Minitab 22, with graphs prepared in Excel.
Results and Discussion
Results indicated that drought stress had a great effect on morphological traits across all the species with Sedum acre being most sensitive, particularly in root length and biomass. Festuca arundinacea had optimal growth and biomass at 60% field capacity, signifying moderate drought tolerance. Physiological and biochemical traits, like relative water content (RWC), electrolyte leakage (EL), chlorophyll content, were all impacted by drought greatly. The greatest shoot height in Festuca was observed under the control condition (80% field capacity), which was not significantly different from the 60% field capacity treatment. However, in Phyla spp., the highest shoot height was recorded at 60% field capacity, which differed significantly from both the milder and more severe stress levels. The highest relative leaf water content (RWC) in tall fescue, goldmoss stonecrop, and phyla plants was observed at 80% field capacity (FC 80%), with no significant difference between the first (80% FC) and second (60% FC) irrigation levels. Furthermore, across all species, RWC generally decreased with increasing drought stress intensity, and the lowest values for this trait were recorded under the most severe stress level (20% FC) for all plants. In all the plant species, the highest levels of electrolyte leakage were observed under the most severe stress conditions (the fourth and third levels of drought stress). Phyla nodiflora maintained higher levels of relative water content during drought stress, demonstrating enhanced tolerance to water scarcity.The findings indicate the potential of drought-resistant groundcovers for water-saving urban landscaping.
Conclusion
The groundcover species examined in this study responded differently to drought stress. Phyla nodiflora performed better in most physiological and morphological parameters with notable tolerance to water deficit stress. On the other hand, Sedum acre was the most sensitive plant to drought. As drought severity increased, key parameters such as root length, fresh biomass, relative water content of leaves, and chlorophyll content reduced, whereas electrolyte leakage increased. These findings reinforce the importance of utilizing drought-tolerant species like Phyla nodiflora for future sustainable desert urban landscape design. Replacement of high-water-demand lawn with such robust groundcovers can help significantly in the preservation of water resources. However, more studies need to be carried out to find out the long-term adaptation and adaptability of these species under diverse weather and irrigation regimes.
