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Showing 13 results for Sedghi
Mohammad Sedghi, Farzaneh Hasani, Raouf Seyed Sharifi,
Volume 1, Issue 2 ((Autumn & Winter) 2015)
Volume 1, Issue 2 ((Autumn & Winter) 2015)
Abstract
Application of zinc can improve the tolerance and resistance of plants especially sunflower to environmental stresses and be effective on kernel set and yield. To investigate the effects of zinc oxide nanoparticles on the length, effective period, the rate of kernel filling and kernel weight in sunflower cultivars, a factorial experiment based on randomized complete block design with three replications was conducted at the University of Mohaghegh Ardabili, Ardabil, Iran. Treatments were three sunflower cultivars as Aline 191, Aline 122 and Farrokh and three concentrations of nano zinc oxide including 0, 0.5 and 1 g lit-1 which sprayed at three stages. Results showed that interaction of cultivar and nano zinc oxide was significant on kernel filling rate, the effective period of kernel filling, maximum kernel weight and duration of kernel filling. The rate of filling and maximum kernel weight increased with 0.5 g lit-1 spraying of Nano zinc oxide in Aline 191 and 122, but in Farrokh cultivar was significantly reduced in comparison to the control. Also, no significant difference was found between 0, 0.5 and 1 g lit-1 of nano zinc oxide on kernel filling rate, effective kernel-filling period and duration in Farrokh cultivar. In conclusion, foliar application of zinc oxide nanoparticles led to the improvement of kernel weight and their filling parameters and the more appropriate response was observed in foreign cultivars for this treatment, while final kernel weight decreased in Farrokh cultivar. Therefore, it can be used 0.5 g lit-1 of nano zinc oxide for increasing grain yield in foreign cultivars of Aline.
Effat Ghaviazm, Mohammad Sedghi, Raouf Seyed Sharifi,
Volume 2, Issue 2 ((Autumn & Winter) 2016)
Volume 2, Issue 2 ((Autumn & Winter) 2016)
Abstract
Marigold (Calendula officinalis) is a medicinal plant belonging to the Asteraceae family, which seems necessary the review of its various features especially the improvement of reproduction in order to the development of vegetation and extraction of raw pharmaceutics materials. In order to study the effects of seed hardening on the quality of seeds harvested from different positions of inflorescence on the storability of pot marigold, an experiment conducted at the University of Mohaghegh Ardabili in 2011. Seeds hardened before planting with CaCl2 2% and distilled water. At harvest, the seeds collected from both inner and outer regions of the inflorescence from storage experiments in the laboratory. Harvested seeds stored for six months at 40°C. Then an experiment conducted as factorial based on a completely randomizes design with four replications at the laboratory. Results showed that the highest germination percentage (96%), rate (3.91 day-1), radicle length (5.71 cm) and seed residual dry weight (0.061 g) were related to outer positioned seeds. The highest plumule length (4.79 cm) and seedling dry weight (0.016 g) obtained from outer seeds hardened with distilled water. In conclusion, for best stability results of pot marigold seeds, it is recommended to harden seeds before planting with water and harvest outer seeds from the inflorescence.
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Narjes Hojati Fahim, Mohamad Sedghi, Mehrdad Chaeichi, Rraouf Seyed Sharifi,
Volume 6, Issue 1 ((Spring and Summer) 2019)
Volume 6, Issue 1 ((Spring and Summer) 2019)
Abstract
Extended Abstract
Introduction: Iran is located in the arid and semi-arid regions of the world with an average rainfall of 240 mm per year, which requires rethinking of the adoption of methods. One of the alternative ways is to use organic and biological fertilizers. Biological fertilizers are considered as the main and the most important factor in the integrated management of plant foods for sustainable agriculture as they play an important role in product improvement and efficiency. Therefore, this research was carried out with the aim of investigating the effect of seed pre-treatment with some organic and biological fertilizers in rainfed wheat.
Materials and Methods: A factorial experiment with three replications was conducted at the Laboratory of Seed and Plant Certification and Registration of the Center of Agriculture and Natural Resources Research located in Hamedan. Seed inoculation was considered in 5 levels (Seafull, Disper Root Gs., Bio-Health, Trichodermin and control) on 8 different rainfed wheat cultivars (Azar-2, Hashtrood, Baran, Rasad, Owhadi, Sardari, Takab and Homa). First, the seeds were disinfected with sodium hypochlorite, and were then cultured in special containers and were placed in the germinator at 20 ° C. After 4 and 8 days, the number of germinated seeds was counted. Germination seeds were counted in each treatment and germination indices such as germination rate, average daily germination, coefficient germination rate, longitudinal vigor index, weight vigor index, seedling fresh weight, root length/shoot ratio, shoot fresh weight, root fresh weight, seed reserve utilization rate, seed reserve utilization efficiency, fraction utilization seed reserve, seed dry weight were calculated.
Results: With application of different levels of fertilizer, the rate of germination treatment Homa×Bio-Health (155%), average daily germination treatment Hashtrood×Bio-Health (69%), coefficient germination rate treatment Owhadi×Disper Root Gs (60%), longitudinal vigor index treatment Owhadi×Bio-Health (108%), weight vigor index treatment Homa×Bio-Health (64%), root fresh weight treatment Hashtrood×Disper Root Gs (106%), shoot fresh weight treatment Hashtrood×Seafull (23%), seedling fresh weight treatment Homa×Bio-Health (42%), root length/shoot ratio treatment Owhadi×Trichodermin (75%), seed reserve utilization rate treatment Homa×Bio-Health (118%), and fraction utilization seed reserve treatment Homa×Bio-Health (119%) increased, compared with the control. In addition, the application of Bio-Health fertilizer and Hashtrood cultivar had the highest amount in almost all the mentioned attributes
Conclusion: Investigation of the different levels of fertilization showed that in most of the indices related to germination and heterotrophic growth of seedling, pretreatment with Bio-Health biofertilizer had a significant difference with other fertilizer levels.
Highlights:
- Evaluation of germination indices for recent cultivars of rainfed wheat, released by rainfed Research Institute of Iran.
- Investigating and comparing fertilizers with various multifactorial compounds (fungi and bacteria) and with each other.
- Conducting research on commercial compounds and comparison of live biochemical and non-organic matters in a single experiment.
Khadijeh Sourazar, Mohammad Sedghi, Raouf Seyed Sharifi,
Volume 9, Issue 1 ((Spring and Summer) 2022)
Volume 9, Issue 1 ((Spring and Summer) 2022)
Abstract
Extended Abstract
Introduction: The germination stage ensures the durability, establishment, and final yield of plants. The final density of plants per unit area is resulted when the planted seeds germinate fully and with adequate rate. Plants mainly undergo abiotic stresses that are a considerable constraint for agricultural production worldwide. Seed priming is one of the simplest and cheap methods to improve seed germination, acceleration of seedling growth and establishment, uniformity, reduction of flowering time, vigorous seedling production, etc which leads to improved quality and yield of crop under stressful and non-stressful conditions. This study aimed to investigate the effect of different types of priming on enzymatic and physiological changes of French bean seed under cobalt chloride stress conditions.
Materials and Methods: To examine the effect of priming on germination indices, the activity of antioxidant enzymes and proteins in French bean under cobalt chloride stress, a factorial experiment was performed in a completely randomized design with three replications. These factors included four levels: seed priming with 100 mg / l salicylic acid and mannitol, control and distilled water (no priming), and three levels of cobalt chloride stress (0, 100, and 200 mg / l).
Results: The results showed that with increasing cobalt chloride concentration, germination indices (germination rate, root length, root fresh weight, stem fresh weight and stem dry weight) decreased. However, in the pretreatment of distilled water, salicylic acid, and mannitol there was a significant increase in germination indices (mean germination time, radicle length, plumule length, fresh radicle weight, and weight plumule) was observed. The interaction effect of priming and cobalt chloride caused an increase in radicle dry weight compared to control × stress treatment. The highest values of fresh radicle weight (14.4 g), dry weight of plumule (0.27 g), and plumule length (0.17 cm) were obtained in hydro priming pretreatment. The results also showed that hormone priming under stress conditions of 200 and 100 mg / l cobalt chloride increased protein content and polyphenol oxidase activity of French bean seedlings compared with the control treatment, respectively. Osmo priming increased the activity of catalase and peroxidase enzymes under stress and non-stress conditions resulted by 200 mg / l cobalt chloride.
Conclusion: according to the results of the present study, cobalt chloride reduced some physiological and biochemical traits of French bean seeds. However, the French bean has a relatively high cobalt chloride tolerance capacity, so that it showed good tolerance to different concentrations of cobalt chloride for up to 9 days.
Highlights:
1- The effect of different concentrations of cobalt chloride and different types of priming on the germination of French bean seeds was investigated.
2- French bean seedling protein content increased under the influence of hormone priming.
Introduction: The germination stage ensures the durability, establishment, and final yield of plants. The final density of plants per unit area is resulted when the planted seeds germinate fully and with adequate rate. Plants mainly undergo abiotic stresses that are a considerable constraint for agricultural production worldwide. Seed priming is one of the simplest and cheap methods to improve seed germination, acceleration of seedling growth and establishment, uniformity, reduction of flowering time, vigorous seedling production, etc which leads to improved quality and yield of crop under stressful and non-stressful conditions. This study aimed to investigate the effect of different types of priming on enzymatic and physiological changes of French bean seed under cobalt chloride stress conditions.
Materials and Methods: To examine the effect of priming on germination indices, the activity of antioxidant enzymes and proteins in French bean under cobalt chloride stress, a factorial experiment was performed in a completely randomized design with three replications. These factors included four levels: seed priming with 100 mg / l salicylic acid and mannitol, control and distilled water (no priming), and three levels of cobalt chloride stress (0, 100, and 200 mg / l).
Results: The results showed that with increasing cobalt chloride concentration, germination indices (germination rate, root length, root fresh weight, stem fresh weight and stem dry weight) decreased. However, in the pretreatment of distilled water, salicylic acid, and mannitol there was a significant increase in germination indices (mean germination time, radicle length, plumule length, fresh radicle weight, and weight plumule) was observed. The interaction effect of priming and cobalt chloride caused an increase in radicle dry weight compared to control × stress treatment. The highest values of fresh radicle weight (14.4 g), dry weight of plumule (0.27 g), and plumule length (0.17 cm) were obtained in hydro priming pretreatment. The results also showed that hormone priming under stress conditions of 200 and 100 mg / l cobalt chloride increased protein content and polyphenol oxidase activity of French bean seedlings compared with the control treatment, respectively. Osmo priming increased the activity of catalase and peroxidase enzymes under stress and non-stress conditions resulted by 200 mg / l cobalt chloride.
Conclusion: according to the results of the present study, cobalt chloride reduced some physiological and biochemical traits of French bean seeds. However, the French bean has a relatively high cobalt chloride tolerance capacity, so that it showed good tolerance to different concentrations of cobalt chloride for up to 9 days.
Highlights:
1- The effect of different concentrations of cobalt chloride and different types of priming on the germination of French bean seeds was investigated.
2- French bean seedling protein content increased under the influence of hormone priming.
Haniyeh Saadat, Mohammad Sedghi, Raouf Seyed Sharifi, Salim Farzaneh,
Volume 9, Issue 2 ((Autumn & Winter) 2023)
Volume 9, Issue 2 ((Autumn & Winter) 2023)
Abstract
Introduction: Today, population growth has placed a significant burden on global agricultural resources. As a result, meeting global food demand and increasing farmers' incomes has become a challenging task. Salinity is one of the most harmful factors in the arid and semi-arid regions of the world that influences crop production. Seed priming is a technology by which seeds are physiologically and biochemically prepared for germination before being placed in their bed and exposed to the ecological conditions of the environment. The aim of this study was to evaluate the efficiency of the effect of chitosan on bean germination indices under salt stress.
Materials and Methods: The experiment was conducted as factorial based on a completely randomized design with four replications in a row (tube or sandwich culture) between filter paper at the University of Mohaghegh Ardabili in 2021. Treatments included four salinity levels (0, 50, 100, and 150 Mm) and four chitosan levels (0, 25, 50, and 75% by weight volume), all of which had been dissolved in 1% acetic acid. The studied traits included germination coefficient, allometric coefficient, daily germination rate, mean daily germination, seedling length and weight index, radicle length, plumule length, seedling length, radicle fresh and dry weight, plumule fresh and dry weight and residual dry weight. Data analysis was performed using the SAS 9.2 software and Duncan's test at p<0.05 probability level was used for mean comparison.
Results: The results showed that salinity stress decreased allometric coefficient (AC), seedling length vigor index (SLVI), radicle and seedling length (RL and SL), and radicle fresh and dry weight (RFW and RDW) and increased daily germination rate (DGS) and residual dry weight (RDW). Seed pretreatment with chitosan increased AC, SLVI, RL, SL, RFW, and RDW. The comparison of the means showed that there was a significant difference between the levels of chitosan so that the highest number of traits was obtained from the use of 75% chitosan and the lowest was obtained from the chitosan-free treatment. SLVI, SL, and RDW in 75% chitosan pre-treatment were higher at about 31, 26, and 27% compared to the control (priming with distilled water), respectively. The highest AC was observed in priming with 50% chitosan. Comparison of the mean for salinity stress also showed that the highest and lowest values of the measured traits respectively were obtained from the application of 0 and 150 Mm salinity levels. Also, with increasing salinity, chitosan increased germination coefficient (GC), seedling weight vigor index (SWVI), plumule length (PL), and plumule fresh and dry weight (PFW and PDW).
Conclusions: The results of this study show that among the different treatments, pre-treatment of seeds with 75 % Chitosan may be considered an effective way to improve seed germination of bean. It also can reduce the harmful effects of salinity stress on some traits in bean seedlings and improve seedling growth. Also, pretreatment with distilled water is an easy, low-cost and effective way to increase bean seedling germination and growth indices. Farmers can use this method for fast germination and better seedling growth under salt stress conditions.
Highlights:
- The effect of different concentrations of chitosan on the germination of bean seeds was investigated.
- Priming with chitosan increased the allometric coefficient, seedling length vigor index, radicle and seedling length, and radicle fresh and dry weight.
- A suitable method for reducing the harmful effects of salinity and increasing germination indicators of beans was introduced.
Haniyeh Saadat, Mohammad Sedghi, Raouf Seyed Sharifi, Salim Farzaneh,
Volume 10, Issue 2 ((Autumn & Winter) 2024)
Volume 10, Issue 2 ((Autumn & Winter) 2024)
Abstract
Extended Abstract
Introduction: At present, the drastic increase in population has created an additional burden on the world's agricultural resources. As a result, meeting global food demand and increasing farmers' incomes has become a challenging task. Salinity is one of the abiotic stresses that strongly affect the germination, growth, and yield of crops. Seed priming is a simple technology that hydrates seeds to the point where the metabolic activity for germination is initiated without radicle emergence. In fact, the seeds are physiologically and biochemically prepared to germinate before being placed in their bed and exposed to environmental conditions. This research was conducted to investigate the effect of seed priming with chitosan on germination indices and biochemical traits of beans under salt stress.
Materials and Methods: This experiment was conducted at the University of Mohaghegh Ardabili in 2021 as a factorial in the form of a completely randomized design with four repetitions. The treatments included four levels of salinity (0, 50, 100, and 150 mM) and four levels of chitosan (0, 0.25, 0.50, and 0.75% w/v), all of which were dissolved in 1% acetic acid.
Results: The results showed that salinity stress decreased germination percentage (GP), peak value (PV), and germination value (GV). However, seed priming with different levels of chitosan, especially 0.75% chitosan, improved GP, PV, and GV by 7, 21, and 17%, respectively, compared to the control. Proline content and polyphenol oxidase enzyme activity went up with increasing salinity. However, the application of chitosan 0.75% increased these traits by 34% and 43%, respectively, compared to the control (priming with distilled water). Electrolyte leakage in priming with 0.75% chitosan decreased by 31% compared to the control, which indicates the maintenance of the cell membrane stability. The content of soluble sugars in the treatment with 0.75% chitosan and 150 mM salinity showed an increase of about 78% compared to the control. The highest correlation among traits was observed between peak value and germination coefficient (r2=0.99) and between proline and polyphenol oxidase enzyme (r2=0.92).
Conclusions: The results of this study show that among the different treatments, pre-treatment of seeds with 75 % Chitosan may be considered an effective way to improve germination indices and biochemical characteristics of beans and it can be used as a treatment to deal with salinity conditions in bean seedlings and improve their seedling growth.
Highlights:
Introduction: At present, the drastic increase in population has created an additional burden on the world's agricultural resources. As a result, meeting global food demand and increasing farmers' incomes has become a challenging task. Salinity is one of the abiotic stresses that strongly affect the germination, growth, and yield of crops. Seed priming is a simple technology that hydrates seeds to the point where the metabolic activity for germination is initiated without radicle emergence. In fact, the seeds are physiologically and biochemically prepared to germinate before being placed in their bed and exposed to environmental conditions. This research was conducted to investigate the effect of seed priming with chitosan on germination indices and biochemical traits of beans under salt stress.
Materials and Methods: This experiment was conducted at the University of Mohaghegh Ardabili in 2021 as a factorial in the form of a completely randomized design with four repetitions. The treatments included four levels of salinity (0, 50, 100, and 150 mM) and four levels of chitosan (0, 0.25, 0.50, and 0.75% w/v), all of which were dissolved in 1% acetic acid.
Results: The results showed that salinity stress decreased germination percentage (GP), peak value (PV), and germination value (GV). However, seed priming with different levels of chitosan, especially 0.75% chitosan, improved GP, PV, and GV by 7, 21, and 17%, respectively, compared to the control. Proline content and polyphenol oxidase enzyme activity went up with increasing salinity. However, the application of chitosan 0.75% increased these traits by 34% and 43%, respectively, compared to the control (priming with distilled water). Electrolyte leakage in priming with 0.75% chitosan decreased by 31% compared to the control, which indicates the maintenance of the cell membrane stability. The content of soluble sugars in the treatment with 0.75% chitosan and 150 mM salinity showed an increase of about 78% compared to the control. The highest correlation among traits was observed between peak value and germination coefficient (r2=0.99) and between proline and polyphenol oxidase enzyme (r2=0.92).
Conclusions: The results of this study show that among the different treatments, pre-treatment of seeds with 75 % Chitosan may be considered an effective way to improve germination indices and biochemical characteristics of beans and it can be used as a treatment to deal with salinity conditions in bean seedlings and improve their seedling growth.
Highlights:
- Seed priming using chitosan improved germination indices of common bean seeds under salt stress.
- Priming with chitosan increased proline and polyphenol oxidase enzyme.
- A chitosan concentration of 0.75 V/W showed a better effect on germination indices and biochemical characteristics.
- Priming with chitosan can be a suitable method to mitigate the negative effects of salinity, increase germination indices, and improve the biochemical characteristics of beans.
Haniyeh Saadat, Mohammad Sedghi,
Volume 10, Issue 2 ((Autumn & Winter) 2024)
Volume 10, Issue 2 ((Autumn & Winter) 2024)
Abstract
Extended abstract
Introduction: Soybean is among the most important oil crops of the world. Currently, 55% of the world's oil is supplied by soybean. Seed aging, an undesirable feature of agriculture, is one of the main problems in agriculture that leads to economic losses. Although aging is an irreversible process, its speed is delayed by proper storage and optimal storage methods. While kept under inappropriate conditions after harvesting, its quality during storage declines. Priming has a direct and indirect effect on the growth and development of plants, and its indirect effects are more beneficial than its direct effects. Priming improves the longevity of low-vigor seeds. During the priming of these seeds, a long time can occur to repair metabolic damage before any progress in germination, which ultimately prevents further deterioration. Several studies have shown that seed treatment with sodium nitroprusside during reaction with reactive oxygen species and increased activity of antioxidant enzymes is essential to protecting plants against stress. The aim of this study was to the investigate the effect of sodium nitroprusside levels on germination indices and antioxidant enzyme activity in soybean seedlings under accelerated aging test.
Materials and Methods: This experiment was conducted in 2023 as a factorial in the form of a completely randomized design with 3 replications at the University of Mohaghegh Ardabili. Experimental treatments included accelerated aging treatment at three levels (0, 24, and 48 hours) and three levels of sodium nitroprusside (0, 100, and 200 ppm).
Results: The results showed that aging reduced germination indices including germination percentage (GP), germination value (GV), and mean daily germination (MDG). Also, priming with different levels of sodium nitroprusside, especially the 200 ppm level, improved these traits, but priming with sodium nitroprusside decreased the mean germination rate (MGR) and the mean germination time (MGT). The superoxide dismutase and ascorbate peroxidase enzyme activity due to priming with sodium nitroprusside 200 ppm compared to the control showed an increase of 22 and 26%, respectively. Also, the content of peroxidase enzyme activity showed an increase of about 34% compared to the control in priming with sodium nitroprusside 200 ppm and 48 hours aging compared to the control. The lowest catalase enzyme (7.7 units mg protein-1 min-1) was in pretreatment with sodium nitroprusside 100 ppm and without aging.
Conclusions: The results of this study show that among the different treatments, pre-treatment of seeds with sodium nitroprusside 200 ppm may be considered an effective way to improve germination indices and antioxidant enzymes activity of soybean and can be used as a treatment to deal with salinity conditions in soybean seedlings and improve their growth.
Highlights:
Introduction: Soybean is among the most important oil crops of the world. Currently, 55% of the world's oil is supplied by soybean. Seed aging, an undesirable feature of agriculture, is one of the main problems in agriculture that leads to economic losses. Although aging is an irreversible process, its speed is delayed by proper storage and optimal storage methods. While kept under inappropriate conditions after harvesting, its quality during storage declines. Priming has a direct and indirect effect on the growth and development of plants, and its indirect effects are more beneficial than its direct effects. Priming improves the longevity of low-vigor seeds. During the priming of these seeds, a long time can occur to repair metabolic damage before any progress in germination, which ultimately prevents further deterioration. Several studies have shown that seed treatment with sodium nitroprusside during reaction with reactive oxygen species and increased activity of antioxidant enzymes is essential to protecting plants against stress. The aim of this study was to the investigate the effect of sodium nitroprusside levels on germination indices and antioxidant enzyme activity in soybean seedlings under accelerated aging test.
Materials and Methods: This experiment was conducted in 2023 as a factorial in the form of a completely randomized design with 3 replications at the University of Mohaghegh Ardabili. Experimental treatments included accelerated aging treatment at three levels (0, 24, and 48 hours) and three levels of sodium nitroprusside (0, 100, and 200 ppm).
Results: The results showed that aging reduced germination indices including germination percentage (GP), germination value (GV), and mean daily germination (MDG). Also, priming with different levels of sodium nitroprusside, especially the 200 ppm level, improved these traits, but priming with sodium nitroprusside decreased the mean germination rate (MGR) and the mean germination time (MGT). The superoxide dismutase and ascorbate peroxidase enzyme activity due to priming with sodium nitroprusside 200 ppm compared to the control showed an increase of 22 and 26%, respectively. Also, the content of peroxidase enzyme activity showed an increase of about 34% compared to the control in priming with sodium nitroprusside 200 ppm and 48 hours aging compared to the control. The lowest catalase enzyme (7.7 units mg protein-1 min-1) was in pretreatment with sodium nitroprusside 100 ppm and without aging.
Conclusions: The results of this study show that among the different treatments, pre-treatment of seeds with sodium nitroprusside 200 ppm may be considered an effective way to improve germination indices and antioxidant enzymes activity of soybean and can be used as a treatment to deal with salinity conditions in soybean seedlings and improve their growth.
Highlights:
- Seed priming using sodium nitroprusside improved germination indices of seed common soybean under aging.
- Priming with sodium nitroprusside increased antioxidant enzyme activity.
- The concentration of 200 ppm sodium nitroprusside showed a better effect on germination indices and biochemical characteristics.
Haniyeh Saadat, Mohammad Sedghi,
Volume 11, Issue 1 ((Spring and Summer) 2024)
Volume 11, Issue 1 ((Spring and Summer) 2024)
Abstract
Extended abstract
Introduction: Salinity is the most significant environmental stress that limits plant productivity by affecting morphology, physiology, and biochemistry of plants, especially in semi-arid and arid regions. Salinity disrupts and eventually delays seedling growth by delaying seed germination and reducing the germination rate. Seed priming stands out as a quick, easy, low-cost, and effective strategy for improving germination, seedling growth parameters, and overall plant defense against abiotic stresses in many crops. It is defined as the pre-sowing seed treatment during which seeds are immersed in water or chemical solutions and are dry until further use. The aim of this study was to assess the effect of priming with sodium nitroprusside on germination indices and biochemical traits in rice seedlings under salinity stress.
Materials and Methods: This experiment was conducted as a factorial based on a completely randomized design with three replications at the University of Mohaghegh Ardabili in 2023. Experimental treatments included four salinity levels (0, 50, 100, and 150 mM) and three levels of sodium nitroprusside (0, 40, and 80 µM).
Results: The results showed that salinity reduced germination and growth indicators including mean daily germination (MDG), germination coefficient (GC), allometric coefficient (AC), radicle length (RL), pedicel length (PL) and seedling length (SL), as well as radicle and pedicel fresh and dry weight (RFW, PFW, RDW and PDW), but seed pretreatment with different levels of sodium nitroprusside, especially the level of 80 µM, improved these traits. Salinity reduced the seedling moisture percentage (SMP), so that the highest SMP (70.13%) was observed in the control treatment. The highest daily germination rate (DGR) and malondialdehyde content (MDA) were observed at a salinity of 150 mM. Priming decreased DGS and MDA, so that the lowest DGS (0.08) and MDA (0.159 mM g-1 FW) were obtained in priming with 80 μM sodium nitroprusside. Also, salinity decreased the activity of the α-amylase enzyme, so the lowest α-amylase activity (7.93 mg g-1 FW seed) was obtained in the control (distilled water) and at a salinity of 150 mM.
Conclusions: The results showed that seed treatment with sodium nitroprusside at 80 µM is the most effective method to improve rice germination and biochemical traits under salinity stress. It can reduce the harmful effects of salinity on some traits in rice seedlings and improve seedling growth.
Highlights:
Introduction: Salinity is the most significant environmental stress that limits plant productivity by affecting morphology, physiology, and biochemistry of plants, especially in semi-arid and arid regions. Salinity disrupts and eventually delays seedling growth by delaying seed germination and reducing the germination rate. Seed priming stands out as a quick, easy, low-cost, and effective strategy for improving germination, seedling growth parameters, and overall plant defense against abiotic stresses in many crops. It is defined as the pre-sowing seed treatment during which seeds are immersed in water or chemical solutions and are dry until further use. The aim of this study was to assess the effect of priming with sodium nitroprusside on germination indices and biochemical traits in rice seedlings under salinity stress.
Materials and Methods: This experiment was conducted as a factorial based on a completely randomized design with three replications at the University of Mohaghegh Ardabili in 2023. Experimental treatments included four salinity levels (0, 50, 100, and 150 mM) and three levels of sodium nitroprusside (0, 40, and 80 µM).
Results: The results showed that salinity reduced germination and growth indicators including mean daily germination (MDG), germination coefficient (GC), allometric coefficient (AC), radicle length (RL), pedicel length (PL) and seedling length (SL), as well as radicle and pedicel fresh and dry weight (RFW, PFW, RDW and PDW), but seed pretreatment with different levels of sodium nitroprusside, especially the level of 80 µM, improved these traits. Salinity reduced the seedling moisture percentage (SMP), so that the highest SMP (70.13%) was observed in the control treatment. The highest daily germination rate (DGR) and malondialdehyde content (MDA) were observed at a salinity of 150 mM. Priming decreased DGS and MDA, so that the lowest DGS (0.08) and MDA (0.159 mM g-1 FW) were obtained in priming with 80 μM sodium nitroprusside. Also, salinity decreased the activity of the α-amylase enzyme, so the lowest α-amylase activity (7.93 mg g-1 FW seed) was obtained in the control (distilled water) and at a salinity of 150 mM.
Conclusions: The results showed that seed treatment with sodium nitroprusside at 80 µM is the most effective method to improve rice germination and biochemical traits under salinity stress. It can reduce the harmful effects of salinity on some traits in rice seedlings and improve seedling growth.
Highlights:
- Seed priming using sodium nitroprusside improved the germination indices of rice seeds under salinity.
- Priming with sodium nitroprusside decreased MDA content and increased α-amylase activity.
- The concentration of 80 µM sodium nitroprusside showed a better effect on germination indices and biochemical characteristics.
Haniyeh Saadat, Mohammad Sedghi,
Volume 11, Issue 1 ((Spring and Summer) 2024)
Volume 11, Issue 1 ((Spring and Summer) 2024)
Abstract
Extended abstract
Introduction: Environmental stresses, including salinity, result in the overproduction of reactive oxygen species, which, at high levels, can cause oxidative damage, impair membrane lipid functions, inactivate enzymes, and impede the metabolic activities of the plant. Salinity affects seedling growth through osmotic stress, ionic toxicity, lack of absorption of essential elements and water, production of free radicals, cell membrane destruction, and reduction of cell division. Seed priming is a quick, easy, low-cost, and effective strategy for improving germination. It is a seed treatment before planting in which seeds are fully immersed in special solutions and dried until further use. Seed priming assists the germinating seed in mitigating saline stress by neutralizing ionic toxicity or by promoting defense mechanisms. This study aimed to assess the effect of seed priming with vitamin U (S-Methylmethionine) on germination and the physiological and biochemical characteristics of sunflower seedlings under salinity stress.
Materials and Methods: This experiment was conducted in 2023 as a factorial based on a completely randomized design with three replications at the University of Mohaghegh Ardabili. Experimental treatments included four salinity levels (0, 50, 100, and 150 mM) and three levels of vitamin U (0, 2, and 4 mM).
Results: The results showed that salinity reduced the germination and growth indicators, including Germination Rate (GR), Germination Percentage (GP), Mean Daily Germination (MDG), Seedling Length (SL), Seedling Dry Weight (SDW), Seedling Length Vigor Index (SLVI), and Seedling Weight Vigor Index (SWVI); but seed pretreatment with different levels of vitamin U, especially the level of 4 mM, improved these traits. Daily Germination Speed (DGS) was higher by about 25% compared with the control treatment without salinity and, in priming with vitamin U compared with the control (distilled water), it showed a decrease of about 32%. Compared with the control (distilled water), the catalase, peroxidase, superoxide dismutase activities, and proline content of seedlings obtained from primed seeds increased respectively by 9%, 8%, 32%, and 47% after vitamin U treatment. With increasing salinity levels, there was a reduction trend in total seed protein content (0.384 mg g-1 FW), and the lowest total seed protein content was observed at salinity 150 mM. Mean Germination Time (MGT) and malondialdehyde content of seedlings in the priming with a concentration of 4 mM vitamin U and without salinity showed a decrease of about 73% and 21%, respectively, compared with the control (distilled water) and salinity 150 mM.
Conclusions: The results of this research showed that sunflower seed priming with vitamin U at a concentration of 4 mM is the most effective method to improve the germination and biochemical characteristics of seedlings, and stimulating antioxidant enzymes can reduce the harmful effects of salinity on some traits in sunflower seedlings and improve seedling growth.
Highlights:
Introduction: Environmental stresses, including salinity, result in the overproduction of reactive oxygen species, which, at high levels, can cause oxidative damage, impair membrane lipid functions, inactivate enzymes, and impede the metabolic activities of the plant. Salinity affects seedling growth through osmotic stress, ionic toxicity, lack of absorption of essential elements and water, production of free radicals, cell membrane destruction, and reduction of cell division. Seed priming is a quick, easy, low-cost, and effective strategy for improving germination. It is a seed treatment before planting in which seeds are fully immersed in special solutions and dried until further use. Seed priming assists the germinating seed in mitigating saline stress by neutralizing ionic toxicity or by promoting defense mechanisms. This study aimed to assess the effect of seed priming with vitamin U (S-Methylmethionine) on germination and the physiological and biochemical characteristics of sunflower seedlings under salinity stress.
Materials and Methods: This experiment was conducted in 2023 as a factorial based on a completely randomized design with three replications at the University of Mohaghegh Ardabili. Experimental treatments included four salinity levels (0, 50, 100, and 150 mM) and three levels of vitamin U (0, 2, and 4 mM).
Results: The results showed that salinity reduced the germination and growth indicators, including Germination Rate (GR), Germination Percentage (GP), Mean Daily Germination (MDG), Seedling Length (SL), Seedling Dry Weight (SDW), Seedling Length Vigor Index (SLVI), and Seedling Weight Vigor Index (SWVI); but seed pretreatment with different levels of vitamin U, especially the level of 4 mM, improved these traits. Daily Germination Speed (DGS) was higher by about 25% compared with the control treatment without salinity and, in priming with vitamin U compared with the control (distilled water), it showed a decrease of about 32%. Compared with the control (distilled water), the catalase, peroxidase, superoxide dismutase activities, and proline content of seedlings obtained from primed seeds increased respectively by 9%, 8%, 32%, and 47% after vitamin U treatment. With increasing salinity levels, there was a reduction trend in total seed protein content (0.384 mg g-1 FW), and the lowest total seed protein content was observed at salinity 150 mM. Mean Germination Time (MGT) and malondialdehyde content of seedlings in the priming with a concentration of 4 mM vitamin U and without salinity showed a decrease of about 73% and 21%, respectively, compared with the control (distilled water) and salinity 150 mM.
Conclusions: The results of this research showed that sunflower seed priming with vitamin U at a concentration of 4 mM is the most effective method to improve the germination and biochemical characteristics of seedlings, and stimulating antioxidant enzymes can reduce the harmful effects of salinity on some traits in sunflower seedlings and improve seedling growth.
Highlights:
- Seed priming using vitamin U improved germination indices of sunflower seed under salinity.
- Priming with vitamin U decreased the content of malondialdehyde and increased the amount of proline and protein.
- The concentration of 4 mM vitamin U revealed a better effect on germination indices and biochemical characteristics.
Gilla Nazari, Mohammad Sedghi, Raouf Seyed Sharifi,
Volume 11, Issue 1 ((Spring and Summer) 2024)
Volume 11, Issue 1 ((Spring and Summer) 2024)
Abstract
Extended abstract
Introduction: Germination and seedling growth are one of the most important stages of plant growth, which determine the degree of success of agricultural systems in production. Seed deterioration due to storage conditions is a challenge that results in diminished germinability poor seedling establishment, the loss of seed vigor, and finally seed mortality. Thus, it is necessary to use methods to increase seed germinability and enhance seedling establishment. The use of plant hormones is one of the methods that can increase seed germinability and optimal plant growth under seed deterioration conditions. Seed priming with plant hormones is among simple and cheap methods to improve seed germination, accelerate seedling growth and establishment, germination uniformity, and production of vigorous seedlings. The purpose of this experiment is to determine the most effective pretreatments of growth hormones to improve the germination and seedling establishment characteristics of deteriorated triticale seeds.
Materials and Methods: 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).
Results: The results showed that seed deterioration reduced the germination percentage. Priming reduced the effect of seed deterioration and improved the germination percentage by 36.9%. As seed deterioration increased, radicle length, seedling length, vigor index, protein content, and protease activity decreased, whereas priming mitigated the effect of seed deterioration on these traits. At the lowest level of seed deterioration (25%), priming with auxin increased radicle length, plumule length, protease activity, and seedling length vigor index by 72.07, 62.06, 73.27, and 77.06, respectively, compared with no priming.
Conclusions: In general, it seems that triticale seed priming with auxin can invigorate deteriorated seeds and increase germination and seedling production uniformity.
Highlights:
Introduction: Germination and seedling growth are one of the most important stages of plant growth, which determine the degree of success of agricultural systems in production. Seed deterioration due to storage conditions is a challenge that results in diminished germinability poor seedling establishment, the loss of seed vigor, and finally seed mortality. Thus, it is necessary to use methods to increase seed germinability and enhance seedling establishment. The use of plant hormones is one of the methods that can increase seed germinability and optimal plant growth under seed deterioration conditions. Seed priming with plant hormones is among simple and cheap methods to improve seed germination, accelerate seedling growth and establishment, germination uniformity, and production of vigorous seedlings. The purpose of this experiment is to determine the most effective pretreatments of growth hormones to improve the germination and seedling establishment characteristics of deteriorated triticale seeds.
Materials and Methods: 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).
Results: The results showed that seed deterioration reduced the germination percentage. Priming reduced the effect of seed deterioration and improved the germination percentage by 36.9%. As seed deterioration increased, radicle length, seedling length, vigor index, protein content, and protease activity decreased, whereas priming mitigated the effect of seed deterioration on these traits. At the lowest level of seed deterioration (25%), priming with auxin increased radicle length, plumule length, protease activity, and seedling length vigor index by 72.07, 62.06, 73.27, and 77.06, respectively, compared with no priming.
Conclusions: In general, it seems that triticale seed priming with auxin can invigorate deteriorated seeds and increase germination and seedling production uniformity.
Highlights:
- Auxin pretreatment had the greatest effect on improving the quality and germination characteristics of deteriorated triticale seeds.
- Effects of using growth regulators pretreatment were investigated in deteriorated triticale seeds.
Haniyeh Saadat, Mohammad Sedghi,
Volume 11, Issue 2 ((Autumn & Winter) 2025)
Volume 11, Issue 2 ((Autumn & Winter) 2025)
Abstract
Extended abstract
Introduction: Salinity stress leads to the excessive production of reactive oxygen species, which at high levels can cause oxidative damage, disrupt membrane lipid functions, inactivate enzymes, and hinder metabolic activities in plants. Salinity affects seedling growth through osmotic stress, ionic toxicity, deficient absorption of essential nutrients and water, production of free radicals, destruction of the cell membrane, and reduced cell division. Utilizing pretreatment methods serves as a simple approach to mitigate the adverse effects of environmental stress. Seed pretreatment induces biochemical changes, such as the activation of enzymes involved in cellular metabolism, inhibition of metabolism, and improved water absorption, thereby aiding the germination process. This study aims to assess the impact of pretreatment on germination characteristics, activity of certain hydrolytic enzymes, and the glyoxylate cycle in marigold seedlings under salinity stress.
Materials and Methods: A factorial experiment was conducted based on a completely randomized design with three replications at the University of Mohaghegh Ardabili in 2023. Experimental treatments included four salinity levels (0, 50, 100, and 150 mM sodium chloride) and four pretreatment methods (control with distilled water, pretreatment with salicylic acid at 100 mg/L, gibberellin at 20 mg/L, and chitosan at 0.8% w/v, dissolved in 1% acetic acid).
Results: The findings indicated that salinity reduced germination percentage, mean daily germination, petiole length, and seedling dry weight. However, pretreatment with salicylic acid, gibberellin, and particularly chitosan significantly improved these parameters. The germination coefficient, radicle length, and seedling fresh weight in chitosan-pretreated groups without salinity were approximately 75%, 68%, and 34% higher compared to the control (distilled water) and 150 mM salinity treatments, respectively. Additionally, the activities of amylase, protease, and malate synthase in chitosan-pretreated groups without salinity increased by approximately 82%, 46%, and 70%, respectively, compared with the control and 150 mM salinity.
Conclusions: The results of this research demonstrate that seed pretreatment using salicylic acid, gibberellin, and especially chitosan is an effective strategy for enhancing germination indices and the activity of certain hydrolytic enzymes and the glyoxylate cycle, thereby alleviating the detrimental effects of salinity on marigold seedlings and promoting their growth.
Highlights:
Introduction: Salinity stress leads to the excessive production of reactive oxygen species, which at high levels can cause oxidative damage, disrupt membrane lipid functions, inactivate enzymes, and hinder metabolic activities in plants. Salinity affects seedling growth through osmotic stress, ionic toxicity, deficient absorption of essential nutrients and water, production of free radicals, destruction of the cell membrane, and reduced cell division. Utilizing pretreatment methods serves as a simple approach to mitigate the adverse effects of environmental stress. Seed pretreatment induces biochemical changes, such as the activation of enzymes involved in cellular metabolism, inhibition of metabolism, and improved water absorption, thereby aiding the germination process. This study aims to assess the impact of pretreatment on germination characteristics, activity of certain hydrolytic enzymes, and the glyoxylate cycle in marigold seedlings under salinity stress.
Materials and Methods: A factorial experiment was conducted based on a completely randomized design with three replications at the University of Mohaghegh Ardabili in 2023. Experimental treatments included four salinity levels (0, 50, 100, and 150 mM sodium chloride) and four pretreatment methods (control with distilled water, pretreatment with salicylic acid at 100 mg/L, gibberellin at 20 mg/L, and chitosan at 0.8% w/v, dissolved in 1% acetic acid).
Results: The findings indicated that salinity reduced germination percentage, mean daily germination, petiole length, and seedling dry weight. However, pretreatment with salicylic acid, gibberellin, and particularly chitosan significantly improved these parameters. The germination coefficient, radicle length, and seedling fresh weight in chitosan-pretreated groups without salinity were approximately 75%, 68%, and 34% higher compared to the control (distilled water) and 150 mM salinity treatments, respectively. Additionally, the activities of amylase, protease, and malate synthase in chitosan-pretreated groups without salinity increased by approximately 82%, 46%, and 70%, respectively, compared with the control and 150 mM salinity.
Conclusions: The results of this research demonstrate that seed pretreatment using salicylic acid, gibberellin, and especially chitosan is an effective strategy for enhancing germination indices and the activity of certain hydrolytic enzymes and the glyoxylate cycle, thereby alleviating the detrimental effects of salinity on marigold seedlings and promoting their growth.
Highlights:
- Seed pretreatment with salicylic acid, gibberellin, and especially chitosan significantly improved germination indices of marigold seeds under salinity conditions.
- This pretreatment enhanced the enzymatic activity of amylase, protease, and malate synthase.
- Chitosan pretreatment exhibited superior effects on germination indices and biochemical characteristics.
Haniyeh Saadat, Mohmmad Sedghi,
Volume 11, Issue 2 ((Autumn & Winter) 2025)
Volume 11, Issue 2 ((Autumn & Winter) 2025)
Abstract
Extended abstract
Introduction: The world population is expected to increase rapidly until 2050. For this reason, it is thought that the existing lands will be insufficient for growing grains in order to meet the increasing food needs in thefuture. The decrease in agricultural lands as a result of the increase in biotic and abiotic stress factors are among the important obstacles to agriculture. Wheat, an annual herbaceous plant, is used as a basic and strategic nutrient both in Iran and in the world. Salinity is one of the major abiotic stresses that threaten global food security by impacting agricultural production, particularly in arid and semi-arid regions of the world. Seed pretreatment is a technique for minimizing emergence time, ensuring consistent germination, and improving crop performance. It is a treatment at pre-sowing, leading to a physiological condition that improves the seed to germinate. The aim of this study was to evaluate the effect of seed priming with salicylic acid on germination and biochemical traits of wheat under salinity stress.
Materials and Methods: The experiment was conducted as factorial arrangement based on a completely randomized design with four replications at the laboratory of the Faculty of Agriculture University of Mohaghegh Ardabili in 2024. Experimental treatments included four salinity levels (0, 50, 100, and 200 mM NaCl) and four levels of salicylic acid (0, 0.1, 0.5 and 1 mM).
Results: The results showed that salinity stress decreased germination percentage and increased the amount of proline and soluble sugars content, but priming with hydro, salicylic acid 0.1 and 0.5 mM especially salicylic acid 1mM improved these traits. The proline and soluble sugars content in priming with 1mM salicylic acid application were 22% and 43% higher than the control (distilled water). The activity of catalase enzyme in 1 mM salicylic acid treatment and salinity of 200 mM compared with the control showed an increase about 61%. Also the highest amount of α-amylase enzyme activity (4.40 mg maltose g-1 FW seed min-1) was obtained in the treatment with 1 mM salicylic acid and without salinity.
Conclusions: The results of this research showed that seed hydropriming (distilled water), and different levels of salicylic acid, especially 1mM salicylic acid by stimulating antioxidant enzymes and neutralizing free radicals can be considered as a growth enhancer and reduce the adverse effects of salinity in wheat plant.
Highlights:
Introduction: The world population is expected to increase rapidly until 2050. For this reason, it is thought that the existing lands will be insufficient for growing grains in order to meet the increasing food needs in thefuture. The decrease in agricultural lands as a result of the increase in biotic and abiotic stress factors are among the important obstacles to agriculture. Wheat, an annual herbaceous plant, is used as a basic and strategic nutrient both in Iran and in the world. Salinity is one of the major abiotic stresses that threaten global food security by impacting agricultural production, particularly in arid and semi-arid regions of the world. Seed pretreatment is a technique for minimizing emergence time, ensuring consistent germination, and improving crop performance. It is a treatment at pre-sowing, leading to a physiological condition that improves the seed to germinate. The aim of this study was to evaluate the effect of seed priming with salicylic acid on germination and biochemical traits of wheat under salinity stress.
Materials and Methods: The experiment was conducted as factorial arrangement based on a completely randomized design with four replications at the laboratory of the Faculty of Agriculture University of Mohaghegh Ardabili in 2024. Experimental treatments included four salinity levels (0, 50, 100, and 200 mM NaCl) and four levels of salicylic acid (0, 0.1, 0.5 and 1 mM).
Results: The results showed that salinity stress decreased germination percentage and increased the amount of proline and soluble sugars content, but priming with hydro, salicylic acid 0.1 and 0.5 mM especially salicylic acid 1mM improved these traits. The proline and soluble sugars content in priming with 1mM salicylic acid application were 22% and 43% higher than the control (distilled water). The activity of catalase enzyme in 1 mM salicylic acid treatment and salinity of 200 mM compared with the control showed an increase about 61%. Also the highest amount of α-amylase enzyme activity (4.40 mg maltose g-1 FW seed min-1) was obtained in the treatment with 1 mM salicylic acid and without salinity.
Conclusions: The results of this research showed that seed hydropriming (distilled water), and different levels of salicylic acid, especially 1mM salicylic acid by stimulating antioxidant enzymes and neutralizing free radicals can be considered as a growth enhancer and reduce the adverse effects of salinity in wheat plant.
Highlights:
- Seed priming with distilled water, and 1mM salicylic acid improved germination percentage of wheat seed under salinity.
- Hydropriming and 1mM salicylic acid increased the activity of catalase, α-amylase, proline and soluble sugars content.
- Priming with 1mM salicylic acid showed a better effect than other treatments on germination indices and biochemical characteristics.
Haniyeh Saadat, Mohammad Sedghi,
Volume 12, Issue 1 ((Spring and Summer) 2025)
Volume 12, Issue 1 ((Spring and Summer) 2025)
Abstract
Objective: This study aimed to evaluate the effect of chitosan on germination indicators and the activity of antioxidant enzymes in safflower seedlings under salinity stress.
Method: The experiment was conducted using a factorial arrangement based on a completely randomized design with three replications at the University of Mohaghegh Ardabili in 2024. The experimental treatments included four salinity levels (0, 50, 100, and 150 mM NaCl) and four concentrations of chitosan (0, 0.2, 0.4, and 0.5% w/v), which were dissolved in 1% acetic acid.
Results: The results showed that salinity stress reduced the germination rate, radicle length, plumule length, seedling length, seedling fresh weight, and seedling dry weight. However, priming with different concentrations of chitosan, especially at 0.5%, improved these traits. The highest daily germination rate (0.114) was observed in the control group (distilled water priming) under 150 mM salinity. The activity of catalase and peroxidase enzymes in the control under 150 mM salinity increased by approximately 43% and 70%, respectively, compared to the 0.5% chitosan treatment under non-saline conditions. Similarly, the activity of superoxide dismutase enzyme in the 0.5% chitosan treatment under 150 mM salinity increased by about 67% compared to the control under non-saline conditions. Furthermore, the ascorbate peroxidase enzyme activity in seeds primed with 0.5% chitosan increased by 37% compared to the control (distilled water priming).
Conclusions: The results indicated that seed treatment with different concentrations of chitosan can mitigate the harmful effects of salinity on some traits of safflower seedlings and improve seedling growth. The best results were achieved when 0.5% chitosan was used under salinity conditions.
Highlights
- Safflower seed priming using 0.5% chitosan improved the germination indices of safflower seeds under salinity stress.
- Safflower seed priming with 0.5% chitosan increased the activity of the superoxide dismutase and ascorbate peroxidase enzymes.
- Priming with chitosan had a better effect on the germination indices and biochemical characteristics of safflower seeds compared to the control.
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