University of Isfahan Journal of Plant Biological Sciences 3041-9603 16 3 2024 09 22 Improvement of growth and yield of pumpkin (Cucurbita pepo L.) plant under field conditions by selenium and silicon application Improvement of growth and yield of pumpkin (Cucurbita pepo L.) plant under field conditions by selenium and silicon application 1 20 29667 10.22108/ijpb.2025.143691.1384 FA Ameneh Mansoori 1 Department of Horticultural Sciences, Faculty of Agriculture, Ilam University, Ilam, Iran Fardin Ghanbari 1 Department of Horticultural Sciences, Faculty of Agriculture, Ilam University, Ilam, Iran Amirali Shayan Department of Horticulture, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran Journal Article 2024 12 15 In developing countries, fertilization is one of the most crucial factors in improving agricultural productivity and ensuring food security. In this research, the effect of six treatments (control (distilled water), 1 mM silicon (Si), 2 mM Si, 5 µM selenium (Se), 10 µM Se, and a combination of Si and Se) was evaluated on various traits of Cucurbita pepo under field conditions. In this regard, an experiment was conducted in a randomized complete block design (RCBD) with three replications at the greenhouse farm of the Faculty of Agriculture, Ilam University, in 2023. At the end of the experimental period, various traits, including growth parameters, plant pigments, yield, and several macro- and micronutrients, were measured. The results showed that spraying Si and Se, along with their combination, improved different traits including yield (33-73%), shoot fresh (29-60%) and dry weight (27-56%), 100- seed weight (16-18%), number of fruits per plant (43-59%), oil percentage (18-27%) and oil yield (40-65%) in the treated squash. Furthermore, Si and Se, separately and in combination, significantly increased chlorophyll content (11-20%), carotenoids (33-43%), and Fe2+, Zn2+, K+, and Na+ in the plants. In conclusion, our study demonstrated that foliar spraying with Si and Se can enhance the growth and yield of Cucurbita pepo under field conditions. Introduction As one of the essential micronutrients and one of fourteen rare elements effective in human health, Selenium (Se) possesses anti-cancer, anti-aging, and immune-enhancing properties (Azizi et al., 2020). Furthermore, Se is considered an essential component of selenoamino acids, selenoproteins, glutathione peroxidase, and thioredoxin reductase (Hu et al., 2023). To enhance its content in human food, Se has been suggested for use as a chemical fertilizer in crops. Followed by Oxygen (O2), Silicon (Si) is the second most abundant element in the Earth's crust and accounts for 32% of the lithosphere. Si is naturally found in the form of silicates, silicon minerals, or in combination with oxygen or other elements such as aluminum, manganese, calcium, sodium, iron, and potassium. Overall, Si mainly constitutes more than 95% of terrestrial rocks, meteorites, water, and the atmosphere (Trejo-Téllez et al., 2020). Si plays a considerable role in plant growth and development. In this context, it generally improves seed germination, photosynthetic activity, stomatal conductance, carbon dioxide uptake, gas exchange, leaf turgor, relative water content (RWC), and plant production and yield (Arif et al., 2021). Additionally, Si can influence plant-water relationships, enhance photosynthesis and nutrient uptake, regulate phytohormone biosynthesis and the activity of specific enzymes, and mitigate oxidative stress (Wadas, 2021). Considering the remarkable effects of Si on plant growth and development, this study aimed to evaluate its effects separately and in combination with Se on some growth, physiological, and yield traits of Cucurbita pepo under field conditions. Materials and Methods This study was conducted at the Agricultural Faculty of Ilam University, utilizing a randomized complete block design (RCBD) with three replications under field conditions in 2023. To produce seedlings, the seeds of Cucurbita pepo (Hamadan accession) were sown in plastic bags and watered regularly. After two weeks, the two-leaf seedlings were transferred to the experimental field, and then, at the four-leaf stage, they were subjected to a treatment that included foliar spraying repeated four times a day at 10-day intervals. The foliar spraying consisted of distilled water (control), Se (5 and 10 μM), Si (1 and 2 mM), and a combination of Si (2 mM) and Se (10 μM). After fully ripening, the fruit and aerial parts of the plants were transferred to the laboratory for measurement of the traits. Result and Discussion The results of this study showed that the application of Si and Se increased the fresh and dry weight of Cucurbita pepo. At low concentrations in wheat, Si has been reported to increase the fresh and dry weights of both the shoot and root (Karimi & Mohsenzadeh, 2016). Previous studies have also documented that respiratory activity in the leaves of Se-treated cabbage was remarkably high, which consequently led to an increase in cabbage yield. Furthermore, it has been demonstrated that Se can enhance the yield of lettuce (Hajiboland & Keivanfar, 2012), which is consistent with our findings regarding growth parameters. In our study, the application of Si and Se increased the number of fruits per plant, as well as the fresh and dry weights, and the yield of Cucurbita pepo. Researchers have previously stated that the foliar application of Se likely improves yield-related traits by influencing physiological processes (Hemmati et al., 2019). Due to the suitable properties of Se, such as its highly antioxidant activity, Se-treated plants have grown appropriately and gained a remarkable increase in oil content (Hemmati et al., 2019). In addition to improving growth traits, Si and Se enhanced oil percentage and yield of the treated plants (Shahidi et al., 2023), which is in agreement with our findings. Elevating the content of chlorophyll and carotenoids, as well as the amount of nutritional elements such as Fe2+, Zn2+, K+, and Na+, is another beneficial effect of applying these substances to plants. In conclusion, the application of Si (particularly 2 mM) and Se (particularly 5 μM) should be employed to improve growth parameters and yield of Cucurbita pepo under field conditions. In developing countries, fertilization is one of the most crucial factors in improving agricultural productivity and ensuring food security. In this research, the effect of six treatments (control (distilled water), 1 mM silicon (Si), 2 mM Si, 5 µM selenium (Se), 10 µM Se, and a combination of Si and Se) was evaluated on various traits of Cucurbita pepo under field conditions. In this regard, an experiment was conducted in a randomized complete block design (RCBD) with three replications at the greenhouse farm of the Faculty of Agriculture, Ilam University, in 2023. At the end of the experimental period, various traits, including growth parameters, plant pigments, yield, and several macro- and micronutrients, were measured. The results showed that spraying Si and Se, along with their combination, improved different traits including yield (33-73%), shoot fresh (29-60%) and dry weight (27-56%), 100- seed weight (16-18%), number of fruits per plant (43-59%), oil percentage (18-27%) and oil yield (40-65%) in the treated squash. Furthermore, Si and Se, separately and in combination, significantly increased chlorophyll content (11-20%), carotenoids (33-43%), and Fe2+, Zn2+, K+, and Na+ in the plants. In conclusion, our study demonstrated that foliar spraying with Si and Se can enhance the growth and yield of Cucurbita pepo under field conditions. Introduction As one of the essential micronutrients and one of fourteen rare elements effective in human health, Selenium (Se) possesses anti-cancer, anti-aging, and immune-enhancing properties (Azizi et al., 2020). Furthermore, Se is considered an essential component of selenoamino acids, selenoproteins, glutathione peroxidase, and thioredoxin reductase (Hu et al., 2023). To enhance its content in human food, Se has been suggested for use as a chemical fertilizer in crops. Followed by Oxygen (O2), Silicon (Si) is the second most abundant element in the Earth's crust and accounts for 32% of the lithosphere. Si is naturally found in the form of silicates, silicon minerals, or in combination with oxygen or other elements such as aluminum, manganese, calcium, sodium, iron, and potassium. Overall, Si mainly constitutes more than 95% of terrestrial rocks, meteorites, water, and the atmosphere (Trejo-Téllez et al., 2020). Si plays a considerable role in plant growth and development. In this context, it generally improves seed germination, photosynthetic activity, stomatal conductance, carbon dioxide uptake, gas exchange, leaf turgor, relative water content (RWC), and plant production and yield (Arif et al., 2021). Additionally, Si can influence plant-water relationships, enhance photosynthesis and nutrient uptake, regulate phytohormone biosynthesis and the activity of specific enzymes, and mitigate oxidative stress (Wadas, 2021). Considering the remarkable effects of Si on plant growth and development, this study aimed to evaluate its effects separately and in combination with Se on some growth, physiological, and yield traits of Cucurbita pepo under field conditions. Materials and Methods This study was conducted at the Agricultural Faculty of Ilam University, utilizing a randomized complete block design (RCBD) with three replications under field conditions in 2023. To produce seedlings, the seeds of Cucurbita pepo (Hamadan accession) were sown in plastic bags and watered regularly. After two weeks, the two-leaf seedlings were transferred to the experimental field, and then, at the four-leaf stage, they were subjected to a treatment that included foliar spraying repeated four times a day at 10-day intervals. The foliar spraying consisted of distilled water (control), Se (5 and 10 μM), Si (1 and 2 mM), and a combination of Si (2 mM) and Se (10 μM). After fully ripening, the fruit and aerial parts of the plants were transferred to the laboratory for measurement of the traits. Result and Discussion The results of this study showed that the application of Si and Se increased the fresh and dry weight of Cucurbita pepo. At low concentrations in wheat, Si has been reported to increase the fresh and dry weights of both the shoot and root (Karimi & Mohsenzadeh, 2016). Previous studies have also documented that respiratory activity in the leaves of Se-treated cabbage was remarkably high, which consequently led to an increase in cabbage yield. Furthermore, it has been demonstrated that Se can enhance the yield of lettuce (Hajiboland & Keivanfar, 2012), which is consistent with our findings regarding growth parameters. In our study, the application of Si and Se increased the number of fruits per plant, as well as the fresh and dry weights, and the yield of Cucurbita pepo. Researchers have previously stated that the foliar application of Se likely improves yield-related traits by influencing physiological processes (Hemmati et al., 2019). Due to the suitable properties of Se, such as its highly antioxidant activity, Se-treated plants have grown appropriately and gained a remarkable increase in oil content (Hemmati et al., 2019). In addition to improving growth traits, Si and Se enhanced oil percentage and yield of the treated plants (Shahidi et al., 2023), which is in agreement with our findings. Elevating the content of chlorophyll and carotenoids, as well as the amount of nutritional elements such as Fe2+, Zn2+, K+, and Na+, is another beneficial effect of applying these substances to plants. In conclusion, the application of Si (particularly 2 mM) and Se (particularly 5 μM) should be employed to improve growth parameters and yield of Cucurbita pepo under field conditions.

https://ijpb.ui.ac.ir/article_29667_8eb31d728db234ab0b6dcb3b59161a75.pdf

University of Isfahan Journal of Plant Biological Sciences 3041-9603 16 3 2024 09 22 The effect of priming on the antioxidant system and seed deterioration indices of triticale (X Triticosecale) The effect of priming on the antioxidant system and seed deterioration indices of triticale (X Triticosecale) 21 48 29741 10.22108/ijpb.2025.145379.1410 FA Gilla Nazari Department of Plant Production and Genetics, Faculty of Agricultural Science and Technology, University of Mohaghegh Ardabili, Ardabil, Iran Mohammad Sedghi Department of Plant Production and Genetics, Faculty of Agricultural Science and Technology, University of Mohaghegh Ardabili, Ardabil, Iran Raouf Seyed Sharifi Department of Plant Production and Genetics, Faculty of Agricultural Science and Technology, University of Mohaghegh Ardabili, Ardabil, Iran Journal Article 2025 05 22 To examine the effect of priming on germination indices and some biochemical traits of deteriorated triticale seeds, a factorial experiment was performed in a completely randomized design with three replications at the Laboratory of Seed Science and Technology, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili in 2023. Treatments included seed deterioration (5%, 15%, and 25%) and priming (no prime, distilled water, cytokinin, spermidine, salicylic acid, and auxin). The hormones used were prepared at a concentration of 1 mM based on preliminary test results. In the initial test, concentrations of 0.25, 0.5, 1, 1.5, and 2 mM of each hormone were tested, and the most suitable concentration was found to be 1 mM. The results showed that priming with auxin caused the most significant increase in the activities of catalase (40.39%), superoxide dismutase (46.7%), polyphenol oxidase (73.01%), and kayagol peroxidase (17.56%) compared to the control. Additionally, the levels of malondialdehyde (21.1 nmol/g fresh weight), hydrogen peroxide (103 nmol/g fresh weight), and superoxide (35 units) were the lowest in priming with auxin. The levels of Maillard and Amadori products increased due to exhaustion, but decreased by 0.63 and 0.017, respectively, in priming with auxin. In general, the results indicate that seed treatment with auxin can mitigate the detrimental effects of exhaustion on certain triticale seedling traits and enhance seedling growth by stimulating antioxidant enzymes and neutralizing free radicals. Introduction Triticale (× Triticosecale), a hybrid of wheat and rye, exhibits superior biomass production and adaptability. However, its seed viability can significantly decline due to deterioration during storage. Seed aging is associated with oxidative stress, membrane degradation, and biochemical changes, including the accumulation of Maillard and Amadori products. These changes impair seedling establishment and vigor. Reactive oxygen species (ROS), including hydrogen peroxide (H₂O₂) and superoxide radicals (O₂⁻), play a crucial role in cellular damage. The antioxidant defense system, particularly enzymes like catalase (CAT), superoxide dismutase (SOD), guaiacol peroxidase (POD), and polyphenol oxidase (PPO), counteract ROS toxicity. Seed priming, particularly with plant growth regulators, has been recognized as a practical approach to mitigate the effects of seed aging by enhancing antioxidant defenses and repairing cellular structures. In this study, we investigated the effects of different priming treatments, including hydropriming, cytokinin, spermidine, salicylic acid, and auxin, on seedling antioxidant activity and deterioration indices under accelerated aging conditions. Materials and Methods A factorial experiment based on a completely randomized design with three replications was conducted at the Seed Science and Technology Laboratory, University of Mohaghegh Ardabili, in 2023. The experiment included three levels of seed deterioration (95%, 85%, and 75% viability) induced through accelerated aging (40 °C and 100% RH), and six priming treatments: control (unprimed), hydropriming, cytokinin, spermidine, salicylic acid, and auxin, all applied at 1 mM concentration based on preliminary trials. Priming was carried out by soaking seeds for 24 hours at 25 °C, followed by drying to their initial moisture content. Antioxidant enzyme activities (CAT, SOD, POD, PPO, and APX), ROS levels (H₂O₂ and O2-), and seed deterioration indicators (Malondialdehyde – MDA, Maillard, and Amadori products) were evaluated using spectrophotometric methods. Antioxidant capacity was also assessed via the DPPH radical scavenging assay. Results and Discussion Priming with auxin significantly enhanced the activity of CAT, SOD, POD, and PPO, especially under high deterioration (75% viability). CAT activity increased by 40.39%, SOD by 46.7%, PPO by 73.01%, and POD by 17.56% compared to unprimed controls. These enhancements imply a stronger enzymatic detoxification of ROS, improving the seedling's resilience under oxidative stress. Ascorbate peroxidase (APX) activity was also highest in auxin-primed seeds under severe aging. Auxin-primed seeds exhibited the lowest levels of H₂O₂ (103 nmol/g FW) and superoxide (35 U/1000), indicating efficient ROS neutralization. Conversely, unprimed seeds with viability below 75% showed the highest ROS accumulation. DPPH radical scavenging activity was also significantly higher in auxin-primed seeds, confirming improved antioxidant potential. Malondialdehyde (MDA), a key marker of membrane lipid peroxidation, was lowest in auxin-primed seeds (21.1 nmol/g FW) and highest in cytokinin-primed seeds under severe aging (60.2 nmol/g FW). This reduction in MDA highlights the protective role of auxin against membrane degradation. Both Amadori and Maillard product levels were elevated under seed aging, but auxin priming substantially reduced their accumulation. Amadori content dropped to 0.017 (A550), and Maillard product index declined to 0.63%, indicating reduced non-enzymatic glycation and oxidative damage to proteins. Auxin may activate transcription factors and gene networks associated with antioxidant enzymes, enhancing their expression during germination. Similar observations were reported in rice and soybean, where auxin priming improved photosynthesis, chlorophyll content, and stress tolerance by modulating ROS signaling. Polyamines, such as spermidine, also showed beneficial effects by stabilizing membranes and scavenging ROS, although to a lesser extent than auxin. Conclusion Priming triticale seeds with auxin significantly enhances antioxidant enzyme activities, mitigates oxidative damage, and reduces biochemical markers of seed deterioration. This leads to improved seedling vigor even under severe aging stress. Among the treatments studied, auxin was the most effective in restoring physiological and biochemical seed quality, followed by salicylic acid and spermidine. Seed priming, therefore, represents a promising pre-sowing strategy to extend seed longevity and enhance field emergence under stress conditions. To examine the effect of priming on germination indices and some biochemical traits of deteriorated triticale seeds, a factorial experiment was performed in a completely randomized design with three replications at the Laboratory of Seed Science and Technology, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili in 2023. Treatments included seed deterioration (5%, 15%, and 25%) and priming (no prime, distilled water, cytokinin, spermidine, salicylic acid, and auxin). The hormones used were prepared at a concentration of 1 mM based on preliminary test results. In the initial test, concentrations of 0.25, 0.5, 1, 1.5, and 2 mM of each hormone were tested, and the most suitable concentration was found to be 1 mM. The results showed that priming with auxin caused the most significant increase in the activities of catalase (40.39%), superoxide dismutase (46.7%), polyphenol oxidase (73.01%), and kayagol peroxidase (17.56%) compared to the control. Additionally, the levels of malondialdehyde (21.1 nmol/g fresh weight), hydrogen peroxide (103 nmol/g fresh weight), and superoxide (35 units) were the lowest in priming with auxin. The levels of Maillard and Amadori products increased due to exhaustion, but decreased by 0.63 and 0.017, respectively, in priming with auxin. In general, the results indicate that seed treatment with auxin can mitigate the detrimental effects of exhaustion on certain triticale seedling traits and enhance seedling growth by stimulating antioxidant enzymes and neutralizing free radicals. Introduction Triticale (× Triticosecale), a hybrid of wheat and rye, exhibits superior biomass production and adaptability. However, its seed viability can significantly decline due to deterioration during storage. Seed aging is associated with oxidative stress, membrane degradation, and biochemical changes, including the accumulation of Maillard and Amadori products. These changes impair seedling establishment and vigor. Reactive oxygen species (ROS), including hydrogen peroxide (H₂O₂) and superoxide radicals (O₂⁻), play a crucial role in cellular damage. The antioxidant defense system, particularly enzymes like catalase (CAT), superoxide dismutase (SOD), guaiacol peroxidase (POD), and polyphenol oxidase (PPO), counteract ROS toxicity. Seed priming, particularly with plant growth regulators, has been recognized as a practical approach to mitigate the effects of seed aging by enhancing antioxidant defenses and repairing cellular structures. In this study, we investigated the effects of different priming treatments, including hydropriming, cytokinin, spermidine, salicylic acid, and auxin, on seedling antioxidant activity and deterioration indices under accelerated aging conditions. Materials and Methods A factorial experiment based on a completely randomized design with three replications was conducted at the Seed Science and Technology Laboratory, University of Mohaghegh Ardabili, in 2023. The experiment included three levels of seed deterioration (95%, 85%, and 75% viability) induced through accelerated aging (40 °C and 100% RH), and six priming treatments: control (unprimed), hydropriming, cytokinin, spermidine, salicylic acid, and auxin, all applied at 1 mM concentration based on preliminary trials. Priming was carried out by soaking seeds for 24 hours at 25 °C, followed by drying to their initial moisture content. Antioxidant enzyme activities (CAT, SOD, POD, PPO, and APX), ROS levels (H₂O₂ and O2-), and seed deterioration indicators (Malondialdehyde – MDA, Maillard, and Amadori products) were evaluated using spectrophotometric methods. Antioxidant capacity was also assessed via the DPPH radical scavenging assay. Results and Discussion Priming with auxin significantly enhanced the activity of CAT, SOD, POD, and PPO, especially under high deterioration (75% viability). CAT activity increased by 40.39%, SOD by 46.7%, PPO by 73.01%, and POD by 17.56% compared to unprimed controls. These enhancements imply a stronger enzymatic detoxification of ROS, improving the seedling's resilience under oxidative stress. Ascorbate peroxidase (APX) activity was also highest in auxin-primed seeds under severe aging. Auxin-primed seeds exhibited the lowest levels of H₂O₂ (103 nmol/g FW) and superoxide (35 U/1000), indicating efficient ROS neutralization. Conversely, unprimed seeds with viability below 75% showed the highest ROS accumulation. DPPH radical scavenging activity was also significantly higher in auxin-primed seeds, confirming improved antioxidant potential. Malondialdehyde (MDA), a key marker of membrane lipid peroxidation, was lowest in auxin-primed seeds (21.1 nmol/g FW) and highest in cytokinin-primed seeds under severe aging (60.2 nmol/g FW). This reduction in MDA highlights the protective role of auxin against membrane degradation. Both Amadori and Maillard product levels were elevated under seed aging, but auxin priming substantially reduced their accumulation. Amadori content dropped to 0.017 (A550), and Maillard product index declined to 0.63%, indicating reduced non-enzymatic glycation and oxidative damage to proteins. Auxin may activate transcription factors and gene networks associated with antioxidant enzymes, enhancing their expression during germination. Similar observations were reported in rice and soybean, where auxin priming improved photosynthesis, chlorophyll content, and stress tolerance by modulating ROS signaling. Polyamines, such as spermidine, also showed beneficial effects by stabilizing membranes and scavenging ROS, although to a lesser extent than auxin. Conclusion Priming triticale seeds with auxin significantly enhances antioxidant enzyme activities, mitigates oxidative damage, and reduces biochemical markers of seed deterioration. This leads to improved seedling vigor even under severe aging stress. Among the treatments studied, auxin was the most effective in restoring physiological and biochemical seed quality, followed by salicylic acid and spermidine. Seed priming, therefore, represents a promising pre-sowing strategy to extend seed longevity and enhance field emergence under stress conditions.

https://ijpb.ui.ac.ir/article_29741_39ec43e9e83122533059660247e88599.pdf

University of Isfahan Journal of Plant Biological Sciences 3041-9603 16 3 2024 09 22 The effect of atmospheric cold plasma and cadmium stress on germination and biochemical indices of different quinoa genotypes The effect of atmospheric cold plasma and cadmium stress on germination and biochemical indices of different quinoa genotypes 49 78 29748 10.22108/ijpb.2025.145113.1407 FA Salim Farzaneh 1 Department of Plant Production and Genetics, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran. Fatemeh Mahmoudi Department of Plant Production and Genetics, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran. Journal Article 2025 05 03 One of the technologies used to improve seed germination is the use of cold plasma. To investigate the effect of atmospheric cold plasma and cadmium stress on the germination and biochemical indices of different quinoa genotypes, a factorial experiment was conducted in a completely randomized design with three replications at the University of Mohaghegh Ardabili. The experimental treatments included cadmium concentrations at three levels (zero (control), 50, and 150 mg/L), cold plasma duration at three levels (0 (control), 10, and 30 seconds), and quinoa genotypes at three levels (Titicaca, Q26, and Giza). The results showed that as stress intensity increased, the average germination percentage and rate, as well as the dry weight and length of quinoa seedlings, decreased. Overall, it appears that among the studied cultivars, the Q26 cultivar yielded better results compared to the other cultivars. Additionally, 30 seconds of cold plasma treatment had the most positive effect on the germination and seedling growth of quinoa cultivars under different levels of cadmium stress, increasing seed and seedling vigor, and enhancing the activity of antioxidant enzymes. Introduction Heavy metal stress is one of the most critical abiotic factors that has garnered considerable attention over the last 30 years. Heavy metal is any element that exhibits a high density and exerts its lethal effects even when present in small amounts. Quinoa is a multipurpose plant that has recently been incorporated into the human diet as a substitute for animal products, serving as a source of protein. With the increasing world population, there is a need to provide more food. On the other hand, the role of new technologies in increasing health and production has a significant contribution. Plasma is often referred to as the fourth state of matter. The energy level rises from solid to liquid and gas, and finally to the ionized state of plasma. Cold atmospheric pressure plasma (CAP) has garnered increasing attention in recent years for its applications in biomedical, environmental, and agricultural fields. A wide range of effects of cold plasma treatment is observed in agricultural applications, including its impact on seed germination and seedling growth. Considering the importance of quinoa and the problems in the field of germination and seedling growth (due to the sensitivity and criticality of these stages), the use of the cold plasma technique in quinoa can be considered one of the solutions that can directly and indirectly improve germination and seedling establishment under heavy metal stress conditions. Therefore, this study aimed to investigate the effect of atmospheric cold plasma and cadmium stress on germination and biochemical indices of different quinoa genotypes. Materials and Methods The experimental treatments included cadmium concentrations at three levels (zero (control), 50, and 150 mg/L), cold plasma duration at three levels (zero (control), 10, and 30 seconds), and quinoa genotypes at three levels (Titicaca, Q26, and Giza). The quinoa seeds used in this study were the varieties T-T Kaka, Q26, and Giza (with a seed purity of 99%, a germination rate of 95%, and a thousand-seed weight of 2.6 g), purchased from Pakan Seed Company, Isfahan. Before applying the treatments, the seeds were disinfected with 2% sodium hypochlorite for one minute and then washed with distilled water. For the atmospheric cold plasma treatment, the seeds were exposed to cold argon (Ar) plasma for 10 and 30 seconds. Cold plasma device (DBD): The distance between the dielectrics was 3 mm. Argon was used as a functional gas between the dielectrics. After cold plasma treatment, the seeds were transferred to Petri dishes for germination testing. To perform the germination test, 50 quinoa seeds were randomly placed in three replicates in the Petri dishes using the top of paper method, and based on the desired treatments, cadmium solutions at concentrations of 50 and 150 mg/L were added to the Petri dishes (distilled water was used for the control treatment). The samples were then transferred to a germination chamber at 20°C and kept in this condition for 10 days. The method of Chang & Koa (1988) was used to prepare the enzyme extract. The activity of the catalase enzyme was measured according to the method of Aebi (1984), and the peroxidase enzyme was measured according to the method of Chanec Maehly & (1955), based on the formation of tetraguaiacol from guaiacol in the presence of hydrogen peroxide and guaiacol enzyme. The activity of the polyphenol oxidase enzyme was measured by the method of Kar & Mishra (1955). Statistical analysis of data was done using SAS 9.4 statistical software. The normality of data distribution was evaluated using the Kolmogorov-Smirnov test. The comparison of means was done using Duncan's multiple range test at the 5% probability level. Excel software was used to draw graphs. Results and Discussion The results showed that as stress intensity increased, the average germination percentage and rate, as well as the dry weight and length of quinoa seedlings, decreased. In non-stressed conditions, the germination percentage and rate, and dry weight of seedlings obtained from seeds pretreated with cold plasma in the Q26 cultivar were significantly higher than those of the control seeds. Additionally, the duration of cold plasma treatment increased the traits of germination percentage, germination rate, average germination percentage, seedling length, and dry weight, as well as catalase, peroxidase, and polyphenol oxidase enzyme activities, saponin, and proline content. However, it decreased the average germination duration and time to 90% germination. Treatment of seeds with cold plasma for 30 seconds increased the seedling length by 53.79% compared to the control treatment. In all the traits studied, the Q26 cultivar was superior to the Titicaca and Giza cultivars. Conclusion Overall, it appears that among the studied cultivars, the Q26 cultivar yielded better results compared to the other cultivars. Additionally, 30 seconds of cold plasma treatment had the most positive effect on the germination and seedling growth of quinoa cultivars under different levels of cadmium stress, increasing seed and seedling vigor, and enhancing the activity of antioxidant enzymes. One of the technologies used to improve seed germination is the use of cold plasma. To investigate the effect of atmospheric cold plasma and cadmium stress on the germination and biochemical indices of different quinoa genotypes, a factorial experiment was conducted in a completely randomized design with three replications at the University of Mohaghegh Ardabili. The experimental treatments included cadmium concentrations at three levels (zero (control), 50, and 150 mg/L), cold plasma duration at three levels (0 (control), 10, and 30 seconds), and quinoa genotypes at three levels (Titicaca, Q26, and Giza). The results showed that as stress intensity increased, the average germination percentage and rate, as well as the dry weight and length of quinoa seedlings, decreased. Overall, it appears that among the studied cultivars, the Q26 cultivar yielded better results compared to the other cultivars. Additionally, 30 seconds of cold plasma treatment had the most positive effect on the germination and seedling growth of quinoa cultivars under different levels of cadmium stress, increasing seed and seedling vigor, and enhancing the activity of antioxidant enzymes. Introduction Heavy metal stress is one of the most critical abiotic factors that has garnered considerable attention over the last 30 years. Heavy metal is any element that exhibits a high density and exerts its lethal effects even when present in small amounts. Quinoa is a multipurpose plant that has recently been incorporated into the human diet as a substitute for animal products, serving as a source of protein. With the increasing world population, there is a need to provide more food. On the other hand, the role of new technologies in increasing health and production has a significant contribution. Plasma is often referred to as the fourth state of matter. The energy level rises from solid to liquid and gas, and finally to the ionized state of plasma. Cold atmospheric pressure plasma (CAP) has garnered increasing attention in recent years for its applications in biomedical, environmental, and agricultural fields. A wide range of effects of cold plasma treatment is observed in agricultural applications, including its impact on seed germination and seedling growth. Considering the importance of quinoa and the problems in the field of germination and seedling growth (due to the sensitivity and criticality of these stages), the use of the cold plasma technique in quinoa can be considered one of the solutions that can directly and indirectly improve germination and seedling establishment under heavy metal stress conditions. Therefore, this study aimed to investigate the effect of atmospheric cold plasma and cadmium stress on germination and biochemical indices of different quinoa genotypes. Materials and Methods The experimental treatments included cadmium concentrations at three levels (zero (control), 50, and 150 mg/L), cold plasma duration at three levels (zero (control), 10, and 30 seconds), and quinoa genotypes at three levels (Titicaca, Q26, and Giza). The quinoa seeds used in this study were the varieties T-T Kaka, Q26, and Giza (with a seed purity of 99%, a germination rate of 95%, and a thousand-seed weight of 2.6 g), purchased from Pakan Seed Company, Isfahan. Before applying the treatments, the seeds were disinfected with 2% sodium hypochlorite for one minute and then washed with distilled water. For the atmospheric cold plasma treatment, the seeds were exposed to cold argon (Ar) plasma for 10 and 30 seconds. Cold plasma device (DBD): The distance between the dielectrics was 3 mm. Argon was used as a functional gas between the dielectrics. After cold plasma treatment, the seeds were transferred to Petri dishes for germination testing. To perform the germination test, 50 quinoa seeds were randomly placed in three replicates in the Petri dishes using the top of paper method, and based on the desired treatments, cadmium solutions at concentrations of 50 and 150 mg/L were added to the Petri dishes (distilled water was used for the control treatment). The samples were then transferred to a germination chamber at 20°C and kept in this condition for 10 days. The method of Chang & Koa (1988) was used to prepare the enzyme extract. The activity of the catalase enzyme was measured according to the method of Aebi (1984), and the peroxidase enzyme was measured according to the method of Chanec Maehly & (1955), based on the formation of tetraguaiacol from guaiacol in the presence of hydrogen peroxide and guaiacol enzyme. The activity of the polyphenol oxidase enzyme was measured by the method of Kar & Mishra (1955). Statistical analysis of data was done using SAS 9.4 statistical software. The normality of data distribution was evaluated using the Kolmogorov-Smirnov test. The comparison of means was done using Duncan's multiple range test at the 5% probability level. Excel software was used to draw graphs. Results and Discussion The results showed that as stress intensity increased, the average germination percentage and rate, as well as the dry weight and length of quinoa seedlings, decreased. In non-stressed conditions, the germination percentage and rate, and dry weight of seedlings obtained from seeds pretreated with cold plasma in the Q26 cultivar were significantly higher than those of the control seeds. Additionally, the duration of cold plasma treatment increased the traits of germination percentage, germination rate, average germination percentage, seedling length, and dry weight, as well as catalase, peroxidase, and polyphenol oxidase enzyme activities, saponin, and proline content. However, it decreased the average germination duration and time to 90% germination. Treatment of seeds with cold plasma for 30 seconds increased the seedling length by 53.79% compared to the control treatment. In all the traits studied, the Q26 cultivar was superior to the Titicaca and Giza cultivars. Conclusion Overall, it appears that among the studied cultivars, the Q26 cultivar yielded better results compared to the other cultivars. Additionally, 30 seconds of cold plasma treatment had the most positive effect on the germination and seedling growth of quinoa cultivars under different levels of cadmium stress, increasing seed and seedling vigor, and enhancing the activity of antioxidant enzymes.

https://ijpb.ui.ac.ir/article_29748_802ae2df413edf1e182d61a91d46672b.pdf

University of Isfahan Journal of Plant Biological Sciences 3041-9603 16 3 2024 09 22 The effect of plant growth regulators and biostimulants on callus formation of Catharanthus roseus The effect of plant growth regulators and biostimulants on callus formation of Catharanthus roseus 79 94 29788 10.22108/ijpb.2025.145277.1409 FA Arezoo Sabahi Ojnaz Department of Production Engineering and Plant Genetics, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili Nasser Zare Department of Production Engineering and Plant Genetics, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili Roghayyeh Hazrati Department of Production Engineering and Plant Genetics, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili Rasool Asghari‑Zakaria Department of Production Engineering and Plant Genetics, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili Parisa Sheikhzadeh Department of Production Engineering and Plant Genetics, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili Journal Article 2025 05 14 Catharanthus roseus is a medicinal plant that is of great importance due to its abundant production of the alkaloids vincristine and vinblastine and their use in the production of anticancer drugs. Given the high price of these compounds and their small amounts in this plant, efforts to increase the production of these compounds have led to extensive research on this plant. The aim of the present study is to investigate and test various factors affecting callus formation in Catharanthus roseus, such as plant hormones (2.4-D (0.5, 1, 1.5 mg/L), NAA (0.5, 1, 3 mg/L), and BAP (0.5, 1, 3 mg/L)), ascorbic acid (50, 100, and 150 mg/L), melatonin, and yeast extract (50, 100, and 150 mg/L), as well as to investigate the best method for disinfecting Catharanthus roseus seeds. The results of the study showed that for disinfection of Parvansh seeds, the best method with the highest percentage of survival and the lowest percentage of fungal and bacterial contamination is related to the anti-infection of sodium hypochlorite at 2.5%. Also, the appropriate culture medium for callus growth is MS culture medium containing 1 mg/L NAA and 1 mg/L BAP. Also, in the ascorbic acid treatment, the highest fresh weight of callus was observed in the 150 mg/L ascorbic acid treatment (0.0872), which had the least color change (browning). Also, the results of examining the morphological characteristics of calluses treated with melatonin and yeast extract showed that the highest percentage of callus formation and the highest fresh weight of callus were related to yeast extract at a concentration of 150 mg/L. Introduction Medicinal plants have played a vital role in human life since ancient times, and today, about 80% of the medicines we consume have plant roots. Catharanthus roseus, native to Madagascar and tropical regions, is one of these natural treasures that has attracted attention due to its valuable medicinal compounds, especially anticancer alkaloids such as vinblastine and vincristine. For the sustainable production of these compounds, modern cultivation methods such as in vitro culture (tissue culture) are used. In this method, different parts of the plant, such as callus, hairy roots, stem, and leaves, can be used to produce seedlings and control the amount of alkaloids. Plant hormones, especially auxin and cytokinin, play a key role in growth and development, as well as the process of callus formation. Research has shown that the appropriate composition and concentration of these hormones can significantly affect the dry weight of callus and the production of alkaloids; For example, the combination of BAP and NAA has yielded positive results. In addition to hormones, substances such as ascorbic acid (vitamin C), yeast extract, and melatonin also help improve callus formation and plant resistance. Ascorbic acid, as a potent antioxidant, plays a role in cell division and growth, and yeast extract increases metabolic activity by providing nutrients and natural hormones. Melatonin, with its antioxidant properties, also reduces oxidative stress and stimulates cell division. The primary objective of this research is to identify the most effective method of seed disinfection and to examine the impact of varying concentrations of plant hormones, ascorbic acid, melatonin, and yeast extract on the callus formation process in the Parvanesh plant, aiming to optimize the production of valuable medicinal compounds. Materials and Methods In this study, Parvansh seeds were obtained from Pakan Seed Company, Isfahan. Seed disinfection and initial cultivation: For seed disinfection, 70% alcohol and three different concentrations of sodium hypochlorite (1.5%, 2.5%, and 5%) were used. After washing and drying, the seeds were cultivated in MS culture medium (without hormones) and first in the dark (temperature 24 ± 2 °C) and then in controlled light conditions (16 hours of light, 8 hours of darkness) for germination. Investigation of hormones for callus formation: When the seedlings reached the 8-leaf stage, the leaves were cut into small pieces (0.5 to 1 cm) and placed as explants on MS culture medium containing different combinations of plant hormones 2.4-D, NAA, and BAP. After 4 weeks, the percentage and fresh weight of calluses were measured. Effect of ascorbic acid: After determining the best hormone combination (NAA 1 mg/L + BAP 1 mg/L), different concentrations of ascorbic acid (50, 100, and 150 mg/L) were added to this culture medium (using a syringe filter for sterilization). Then, leaf explants were cultured on these media, and the percentage and fresh weight of calluses were evaluated. Effect of melatonin and yeast extract: In the next step, melatonin and yeast extract were also added in three similar concentrations (50, 100, and 150 mg/L) to the culture medium containing NAA and BAP hormones (this time before autoclaving). Callus growth was examined after 20 days. Statistical analysis: All experiments were performed in a completely randomized design with three replications, and data were analyzed using SPSS software and Duncan's test. Graphs were also drawn using Excel. Results and Discussion The results showed that the seed disinfection method plays a vital role in the success of cultivation. 2.5% sodium hypochlorite gave the highest percentage of seed viability, indicating its high efficiency in eliminating bacterial and fungal contamination while maintaining seed health. In contrast, 5% sodium hypochlorite had the lowest viability, and the use of 70% alcohol and 1.5% sodium hypochlorite resulted in the highest contamination. Different combinations of plant hormones were tested to stimulate callus formation from leaf explants. The results showed that MS medium containing 1 mg/L NAA and 1 mg/L BAP, as well as MS medium containing 1 mg/L 2,4-D and 0.5 mg/L BAP, produced the highest callus fresh weight. The highest callus formation percentage (95.23%) was also observed in the same hormonal combination (1 mg/L NAA and 1 mg/L BAP), indicating the importance of hormonal balance in the callus formation process. Adding ascorbic acid to the culture medium significantly improved callus formation and callus quality. A concentration of 150 mg/L ascorbic acid not only resulted in the highest callus formation percentage (86.19%) and callus fresh weight, but also significantly prevented callus browning. This indicates that ascorbic acid plays an essential role in reducing oxidative stress and maintaining callus health. In investigating the effect of yeast extract and melatonin, the results showed that yeast extract at different concentrations, especially 150 mg/L, was able to produce 100% callus formation and the highest callus fresh weight (0.633 g). In contrast, melatonin at a concentration of 150 mg/L resulted in the lowest callus percentage and weight. This finding confirms the importance of yeast extract as a rich source of nutrients and growth regulators in improving callus formation. Conclusion The best method of seed disinfection is the use of 2.5% sodium hypochlorite, which provides high viability and low contamination. The optimal composition for callus production includes MS medium with 1 mg/L NAA and 1 mg/L BAP. An ascorbic acid concentration of 150 mg/L has the highest percentage of callus formation. Yeast extract at a concentration of 150 mg/L increases callus formation, but melatonin at higher concentrations inhibits callus growth. Catharanthus roseus is a medicinal plant that is of great importance due to its abundant production of the alkaloids vincristine and vinblastine and their use in the production of anticancer drugs. Given the high price of these compounds and their small amounts in this plant, efforts to increase the production of these compounds have led to extensive research on this plant. The aim of the present study is to investigate and test various factors affecting callus formation in Catharanthus roseus, such as plant hormones (2.4-D (0.5, 1, 1.5 mg/L), NAA (0.5, 1, 3 mg/L), and BAP (0.5, 1, 3 mg/L)), ascorbic acid (50, 100, and 150 mg/L), melatonin, and yeast extract (50, 100, and 150 mg/L), as well as to investigate the best method for disinfecting Catharanthus roseus seeds. The results of the study showed that for disinfection of Parvansh seeds, the best method with the highest percentage of survival and the lowest percentage of fungal and bacterial contamination is related to the anti-infection of sodium hypochlorite at 2.5%. Also, the appropriate culture medium for callus growth is MS culture medium containing 1 mg/L NAA and 1 mg/L BAP. Also, in the ascorbic acid treatment, the highest fresh weight of callus was observed in the 150 mg/L ascorbic acid treatment (0.0872), which had the least color change (browning). Also, the results of examining the morphological characteristics of calluses treated with melatonin and yeast extract showed that the highest percentage of callus formation and the highest fresh weight of callus were related to yeast extract at a concentration of 150 mg/L. Introduction Medicinal plants have played a vital role in human life since ancient times, and today, about 80% of the medicines we consume have plant roots. Catharanthus roseus, native to Madagascar and tropical regions, is one of these natural treasures that has attracted attention due to its valuable medicinal compounds, especially anticancer alkaloids such as vinblastine and vincristine. For the sustainable production of these compounds, modern cultivation methods such as in vitro culture (tissue culture) are used. In this method, different parts of the plant, such as callus, hairy roots, stem, and leaves, can be used to produce seedlings and control the amount of alkaloids. Plant hormones, especially auxin and cytokinin, play a key role in growth and development, as well as the process of callus formation. Research has shown that the appropriate composition and concentration of these hormones can significantly affect the dry weight of callus and the production of alkaloids; For example, the combination of BAP and NAA has yielded positive results. In addition to hormones, substances such as ascorbic acid (vitamin C), yeast extract, and melatonin also help improve callus formation and plant resistance. Ascorbic acid, as a potent antioxidant, plays a role in cell division and growth, and yeast extract increases metabolic activity by providing nutrients and natural hormones. Melatonin, with its antioxidant properties, also reduces oxidative stress and stimulates cell division. The primary objective of this research is to identify the most effective method of seed disinfection and to examine the impact of varying concentrations of plant hormones, ascorbic acid, melatonin, and yeast extract on the callus formation process in the Parvanesh plant, aiming to optimize the production of valuable medicinal compounds. Materials and Methods In this study, Parvansh seeds were obtained from Pakan Seed Company, Isfahan. Seed disinfection and initial cultivation: For seed disinfection, 70% alcohol and three different concentrations of sodium hypochlorite (1.5%, 2.5%, and 5%) were used. After washing and drying, the seeds were cultivated in MS culture medium (without hormones) and first in the dark (temperature 24 ± 2 °C) and then in controlled light conditions (16 hours of light, 8 hours of darkness) for germination. Investigation of hormones for callus formation: When the seedlings reached the 8-leaf stage, the leaves were cut into small pieces (0.5 to 1 cm) and placed as explants on MS culture medium containing different combinations of plant hormones 2.4-D, NAA, and BAP. After 4 weeks, the percentage and fresh weight of calluses were measured. Effect of ascorbic acid: After determining the best hormone combination (NAA 1 mg/L + BAP 1 mg/L), different concentrations of ascorbic acid (50, 100, and 150 mg/L) were added to this culture medium (using a syringe filter for sterilization). Then, leaf explants were cultured on these media, and the percentage and fresh weight of calluses were evaluated. Effect of melatonin and yeast extract: In the next step, melatonin and yeast extract were also added in three similar concentrations (50, 100, and 150 mg/L) to the culture medium containing NAA and BAP hormones (this time before autoclaving). Callus growth was examined after 20 days. Statistical analysis: All experiments were performed in a completely randomized design with three replications, and data were analyzed using SPSS software and Duncan's test. Graphs were also drawn using Excel. Results and Discussion The results showed that the seed disinfection method plays a vital role in the success of cultivation. 2.5% sodium hypochlorite gave the highest percentage of seed viability, indicating its high efficiency in eliminating bacterial and fungal contamination while maintaining seed health. In contrast, 5% sodium hypochlorite had the lowest viability, and the use of 70% alcohol and 1.5% sodium hypochlorite resulted in the highest contamination. Different combinations of plant hormones were tested to stimulate callus formation from leaf explants. The results showed that MS medium containing 1 mg/L NAA and 1 mg/L BAP, as well as MS medium containing 1 mg/L 2,4-D and 0.5 mg/L BAP, produced the highest callus fresh weight. The highest callus formation percentage (95.23%) was also observed in the same hormonal combination (1 mg/L NAA and 1 mg/L BAP), indicating the importance of hormonal balance in the callus formation process. Adding ascorbic acid to the culture medium significantly improved callus formation and callus quality. A concentration of 150 mg/L ascorbic acid not only resulted in the highest callus formation percentage (86.19%) and callus fresh weight, but also significantly prevented callus browning. This indicates that ascorbic acid plays an essential role in reducing oxidative stress and maintaining callus health. In investigating the effect of yeast extract and melatonin, the results showed that yeast extract at different concentrations, especially 150 mg/L, was able to produce 100% callus formation and the highest callus fresh weight (0.633 g). In contrast, melatonin at a concentration of 150 mg/L resulted in the lowest callus percentage and weight. This finding confirms the importance of yeast extract as a rich source of nutrients and growth regulators in improving callus formation. Conclusion The best method of seed disinfection is the use of 2.5% sodium hypochlorite, which provides high viability and low contamination. The optimal composition for callus production includes MS medium with 1 mg/L NAA and 1 mg/L BAP. An ascorbic acid concentration of 150 mg/L has the highest percentage of callus formation. Yeast extract at a concentration of 150 mg/L increases callus formation, but melatonin at higher concentrations inhibits callus growth.

https://ijpb.ui.ac.ir/article_29788_951734c8f01bc83953f191b7bc7eaf34.pdf

University of Isfahan Journal of Plant Biological Sciences 3041-9603 16 3 2024 09 22 Effect of culture filtrate and Serendipita indica cell homogenate on content and chemical composition of essential oil and some physiological traits of lemon balm (Melissa officinalis L.) Effect of culture filtrate and Serendipita indica cell homogenate on content and chemical composition of essential oil and some physiological traits of lemon balm (Melissa officinalis L.) 95 120 29876 10.22108/ijpb.2025.145810.1413 FA Maryam Kiani Department of Plant Production and Genetics, Faculty of Agriculture, Malayer University, Malayer, Iran Mohammad Abdoli Department of Plant Production and Genetics, Faculty of Agriculture, Malayer University, Malayer, Iran Mehdi Ghabooli Department of Plant Production and Genetics, Faculty of Agriculture, Malayer University, Malayer, Iran Journal Article 2025 07 01 Lemon balm (Melissa officinalis L.) is a perennial herb that has antioxidant, anti-bacterial, anti-inflammatory, antifungal, and antitumor activities. The present study aimed to investigate the effect of foliar application of culture filtrate (0 and ½ v/v), Serendipita indica cell homogenate (20, 40, 80, and 160 mg/L), and their combined effect on the content and chemical composition of essential oil and some physiological traits of lemon balm in a completely randomized design with three replications. A total of 38 compounds were identified in M. officinalis essential oils, with the major constituents being citronellal, γ-3-carene, trans-carveol, citral, and linalool (total 25.77 to 40.20%), respectively. The results showed that the effect of treatments on the content of major components of lemon balm essential oil was highly significant at the 1% probability level. The highest essential oil content (0.28%) and major compounds, including citronellal, trans-carveol, citral, and linalool (32, 56, 58, 74, and 63% higher than those in the control plants, respectively) were obtained by ½ culture filtrate plus 160 mg/l cell homogenate treatment. The lowest amount was received in the control treatment (without elicitor). The results showed that the type and amount of these elicitors significantly affected the amount of chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, soluble sugar, malondialdehyde content, proline, and flavonoids compared to the control. Citral showed a positive and significant correlation with citronellal, trans-carveol, and linalool (p ≤ 0.01). The heatmap for the studied traits showed a distinct clustering between the control and the treatments of these elicitors. Overall, foliar application of S. indica culture filtrate and cell homogenate is suggested as a biotic elicitor to improve the production of M. officinalis essential oil and its major compounds. Introduction Lemon balm (Melissa officinalis L.) is a perennial herb that has antioxidant, anti-bacterial, anti-inflammatory, antifungal, and antitumor activities. Unlike other plants of the Lamiaceae family, the essential oil content of lemon balm is relatively low; therefore, it has become one of the most valuable types of essential oils. The use of elicitors can be a suitable approach to increase the production of valuable secondary metabolites in medicinal and aromatic plants. The endophytic fungus, Serendipita indica stimulates the growth of many plant species and also increases the production of secondary metabolites. The present study aimed to investigate the effect of foliar application of culture filtrate and S. indica cell homogenate and their combined impact on the content and chemical composition of essential oil and some physiological traits of M. officinalis. Materials and Methods The present study was conducted in a completely randomized design with 10 treatments and three replications in the research greenhouse of Malayer University. The experimental treatments included foliar application with culture filtrate (0 and ½ v/v), S. indica cell homogenate (20, 40, 80, and 160 mg/L), and the combined effect of ½ culture filtrate with 20, 40, 80, and 160 mg/L of S. indica cell homogenate. Autoclaved S. indica culture medium was used as culture filtrate, and powdered mycelium sediment dissolved in distilled water was used as cell homogenate. The control treatment (0 v/v culture filtrate) was sprayed with distilled water. Foliar application of the biotic elicitors on M. officinalis aerial parts was performed at the 40% flowering stage. Five days after elicitation with culture filtrate and S. indica cell homogenate, aerial parts of treated and control plants were sampled to determine biochemical and physiological traits. The content and chemical composition of essential oil, as well as some physiological traits including chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, proline, malondialdehyde content, soluble sugars, total phenols, and flavonoids were measured. The composition of the essential oils was determined by gas chromatography-mass spectroscopy (GC/MS). The correlation coefficient (r) between measured traits was estimated using the Pearson method. Results and Discussion A total of 38 compounds were identified in M. officinalis essential oils, with citronellal, γ-3-carene, trans-carveol, citral, and linalool being the major constituents (total 25.77 to 40.20%). The results of analysis of variance (ANOVA) showed that the effects of treatments consisting of different concentrations of culture filtrate, S. indica cell homogenate, and their combined effects on the content of major components of lemon balm essential oil were highly significant at the 1% probability level. The highest essential oil content (0.28%) and major compounds, including citronellal, trans-carveol, citral, and linalool (32, 56, 58, 74, and 63% higher than those in the control plants, respectively) were obtained by ½ culture filtrate plus 160 mg/l cell homogenate treatment. The lowest amount was obtained in the control treatment (without elicitor). The results showed that the type and amount of these elicitors significantly affected the amount of chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, soluble sugar, malondialdehyde content, proline, and flavonoids compared to the control. The results of correlation between different traits showed that the amount of essential oil had a positive and significant correlation at the 1% probability level with the major essential oil compounds including citronellal (r=0.986**), trans-carveol (r=0.976**), linalool (r=0.971**), and citral (r=0.962**) and a negative and significant correlation with γ-3-carene (r=-0.976**). Also, citral showed a positive and significant correlation with citronellal, trans-carveol, and linalool (P≤0.01). The heatmap results show that for the essential oil content and the major compounds, including citronellal, trans-carveol, citral, and linalool, the best result was obtained by the treatment of ½ culture filtrate+160 mg/L cell homogenate. Conclusion The current study provided evidence that M. officinalis is a medicinal plant that is well responsive to foliar application of culture filtrate and S. indica cell homogenate applied either alone or together. The results of the heatmap for the studied traits showed that the treated plants could be grouped into three distinct clusters and showed a clear separation between the control and the treatments of these elicitors. Overall, the results indicated that foliar application of S. indica culture filtrate and cell homogenate is suggested as a biotic elicitor to improve the production of M. officinalis essential oil and its major compounds, including linalool, trans-carveol, citronellal, and citral. Lemon balm (Melissa officinalis L.) is a perennial herb that has antioxidant, anti-bacterial, anti-inflammatory, antifungal, and antitumor activities. The present study aimed to investigate the effect of foliar application of culture filtrate (0 and ½ v/v), Serendipita indica cell homogenate (20, 40, 80, and 160 mg/L), and their combined effect on the content and chemical composition of essential oil and some physiological traits of lemon balm in a completely randomized design with three replications. A total of 38 compounds were identified in M. officinalis essential oils, with the major constituents being citronellal, γ-3-carene, trans-carveol, citral, and linalool (total 25.77 to 40.20%), respectively. The results showed that the effect of treatments on the content of major components of lemon balm essential oil was highly significant at the 1% probability level. The highest essential oil content (0.28%) and major compounds, including citronellal, trans-carveol, citral, and linalool (32, 56, 58, 74, and 63% higher than those in the control plants, respectively) were obtained by ½ culture filtrate plus 160 mg/l cell homogenate treatment. The lowest amount was received in the control treatment (without elicitor). The results showed that the type and amount of these elicitors significantly affected the amount of chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, soluble sugar, malondialdehyde content, proline, and flavonoids compared to the control. Citral showed a positive and significant correlation with citronellal, trans-carveol, and linalool (p ≤ 0.01). The heatmap for the studied traits showed a distinct clustering between the control and the treatments of these elicitors. Overall, foliar application of S. indica culture filtrate and cell homogenate is suggested as a biotic elicitor to improve the production of M. officinalis essential oil and its major compounds. Introduction Lemon balm (Melissa officinalis L.) is a perennial herb that has antioxidant, anti-bacterial, anti-inflammatory, antifungal, and antitumor activities. Unlike other plants of the Lamiaceae family, the essential oil content of lemon balm is relatively low; therefore, it has become one of the most valuable types of essential oils. The use of elicitors can be a suitable approach to increase the production of valuable secondary metabolites in medicinal and aromatic plants. The endophytic fungus, Serendipita indica stimulates the growth of many plant species and also increases the production of secondary metabolites. The present study aimed to investigate the effect of foliar application of culture filtrate and S. indica cell homogenate and their combined impact on the content and chemical composition of essential oil and some physiological traits of M. officinalis. Materials and Methods The present study was conducted in a completely randomized design with 10 treatments and three replications in the research greenhouse of Malayer University. The experimental treatments included foliar application with culture filtrate (0 and ½ v/v), S. indica cell homogenate (20, 40, 80, and 160 mg/L), and the combined effect of ½ culture filtrate with 20, 40, 80, and 160 mg/L of S. indica cell homogenate. Autoclaved S. indica culture medium was used as culture filtrate, and powdered mycelium sediment dissolved in distilled water was used as cell homogenate. The control treatment (0 v/v culture filtrate) was sprayed with distilled water. Foliar application of the biotic elicitors on M. officinalis aerial parts was performed at the 40% flowering stage. Five days after elicitation with culture filtrate and S. indica cell homogenate, aerial parts of treated and control plants were sampled to determine biochemical and physiological traits. The content and chemical composition of essential oil, as well as some physiological traits including chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, proline, malondialdehyde content, soluble sugars, total phenols, and flavonoids were measured. The composition of the essential oils was determined by gas chromatography-mass spectroscopy (GC/MS). The correlation coefficient (r) between measured traits was estimated using the Pearson method. Results and Discussion A total of 38 compounds were identified in M. officinalis essential oils, with citronellal, γ-3-carene, trans-carveol, citral, and linalool being the major constituents (total 25.77 to 40.20%). The results of analysis of variance (ANOVA) showed that the effects of treatments consisting of different concentrations of culture filtrate, S. indica cell homogenate, and their combined effects on the content of major components of lemon balm essential oil were highly significant at the 1% probability level. The highest essential oil content (0.28%) and major compounds, including citronellal, trans-carveol, citral, and linalool (32, 56, 58, 74, and 63% higher than those in the control plants, respectively) were obtained by ½ culture filtrate plus 160 mg/l cell homogenate treatment. The lowest amount was obtained in the control treatment (without elicitor). The results showed that the type and amount of these elicitors significantly affected the amount of chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, soluble sugar, malondialdehyde content, proline, and flavonoids compared to the control. The results of correlation between different traits showed that the amount of essential oil had a positive and significant correlation at the 1% probability level with the major essential oil compounds including citronellal (r=0.986**), trans-carveol (r=0.976**), linalool (r=0.971**), and citral (r=0.962**) and a negative and significant correlation with γ-3-carene (r=-0.976**). Also, citral showed a positive and significant correlation with citronellal, trans-carveol, and linalool (P≤0.01). The heatmap results show that for the essential oil content and the major compounds, including citronellal, trans-carveol, citral, and linalool, the best result was obtained by the treatment of ½ culture filtrate+160 mg/L cell homogenate. Conclusion The current study provided evidence that M. officinalis is a medicinal plant that is well responsive to foliar application of culture filtrate and S. indica cell homogenate applied either alone or together. The results of the heatmap for the studied traits showed that the treated plants could be grouped into three distinct clusters and showed a clear separation between the control and the treatments of these elicitors. Overall, the results indicated that foliar application of S. indica culture filtrate and cell homogenate is suggested as a biotic elicitor to improve the production of M. officinalis essential oil and its major compounds, including linalool, trans-carveol, citronellal, and citral.

https://ijpb.ui.ac.ir/article_29876_5698f08b03800abc2eb0f9b0897b9d70.pdf