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Mohsen Malek, Farshid Ghaderi-Far, Benjamin Torabi, Hamidreza Sadeghipour,
Volume 7, Issue 1 (9-2020)
Volume 7, Issue 1 (9-2020)
Abstract
Extended Abstract
Introduction: Seeds, like other materials, are hygroscopic and exchange moisture with their surroundings. The changes in the moisture of seeds during storage depend on their hygroscopic nature and this feature plays an important role in determining the seed quality and longevity. Furthermore, studying the hygroscopic characteristics if seeds can be useful in seed storage studies as well as in commercial applications such as drying and seeds processing. Therefore, in this study, the relationship between seed moisture content and relative humidity in seed of rapeseed cultivars was studied.
Material and Methods: In this study, the relationship between the ambient relative humidity and seed moisture content of three rapeseed cultivars at 10, 20 and 30 °C was investigated using hygroscopic equilibrium curves. Therefore, water desorption and absorption curves were studied separately. Water absorption and desorption curves were obtained by drying the seeds at 1% relative humidity and seed hydration at 100% relative humidity, respectively, followed by transferring the seeds to different relative humidities at different temperatures and finally determining the equilibrium moisture content of the seeds. It should be noted that glycerol and sulfuric acid solutions were used to creation different relative humidity. Finally, the relationship between seeds moisture content against the relative humidity was quantified by fitting the D’Arcy-Watt equation.
Results: The results indicated that the seeds moisture content varied in cultivars and temperatures at different relative humidities. Also, there was a difference between water desorption and absorption curves in all cultivars and temperatures; desorption curves were generally higher than water absorption curves. The greatest difference among the cultivars regarding seed moisture content was observed at 100% relative humidity, and this difference was less severe at lower relative humidities. Also, the highest seed moisture content of rapeseed cultivars was observed at 20 °C and 100% relative humidity, and the lowest seed moisture content was recorded at 30 °C and 1% relative humidity.
Conclusions: According to the results, it was found that the relationship between seed moisture content and relative humidity followed a sigmoidal function, and this relationship would also vary depending on cultivar and temperature. There was also a difference between the adsorption and desorption curves, which is called "hysteresis", and showed that the seed moisture content at a constant relative humidity was generally higher in the state of dehydration compared with that in the state of hydration. Due to this event, desorption curve is situated higher than the absorption curve.
Highlights:
- Response to hygroscopic equilibrium curves in seeds of different rapeseed cultivars was compared.
- Sulfuric acid and glycerol solutions were used to create different relative humidity.
Hamed Zamani, Hamidreza Mobasser, Aidin Hamidi, Alireza Daneshmand,
Volume 7, Issue 2 (3-2021)
Volume 7, Issue 2 (3-2021)
Abstract
Extended Abstract
Introduction: Seed is the fundamental input of crop production and tobacco is cultivated as transplanting and its transplant produced as float system. Therefore, seed germination and produced seedling health and diseases and pests management have high importance. So, evaluation of seeds dressing effect on germination and important pests and diseases management in the nursery for healthy transplantable seedling production is important. The study aims to investigate the effect of disinfectant of K326 tobacco seed on germination and percentage of transmissible transplants and management of contamination of sciaridae fly, aphid, and collar rot in a float system tray.
Material and method: This study was conducted as a completely randomized design in 3 replications at Tirtash Research and Education Center in 2014. seeds dressed by pelleting apparatus disinfected with Metalaxyl (Ridomil) and Thiophanate–methyl (TopsinM) fungicides and Imidacloprid (Gaucho), Thiamethoxam (Confidor) and Thiodicarb (Larvin) insecticide and seeds heating by 60ºC temperature warm air during 1 hour, seeds treatment by 50ºC heat water for 10 minutes and treatment by 0.5 percent concentration sodium hypochlorite for 4 minutes. Then normal seedlings percent by standard germination test, seedling emergence percent in float system, transplantable seedling of float system and infected to Sciarid fly, aphid and stem rot seedlings determined.
Results: Results showed that K326 Tobacco Seeds Disinfected by 2.5 g/kg metallaxyl + 2.5 g/kg thiophane-methyl (70% wettable powder) + 10 g/kg imidacloprid + 6 cm3/kg Thiodicarb had the highest percentage of normal seedlings, percentage of seedling emergence in the float system tray and percentage of removable transplants and the least seedling contaminated with sciaridae, aphid and collar rot.
Conclusion: Results of this study showed that all seed disinfection treatments improved seed germination, seedling emergence percentage, and removable seedlings in the float system tray as well as infected seedlings compared to control decreased collar rot, sciaridae fly, and aphids. Also, the mentioned traits were superior to the non-chemical disinfectant treatments in seed disinfection treatments with the studied fungicides and insecticides.
Highlights:
1- The effects of chemical disinfectant treatments (different insecticides and fungicides permitted and common) as coatings on seed germination and percentage of tobacco seedling emergence were evaluated and compared.
ed The effect of non-chemical disinfectant treatments on seed germination and percentage of tobacco seedling emergence and management of pests and diseases seedbed were evaluated and compared.
Introduction: Seed is the fundamental input of crop production and tobacco is cultivated as transplanting and its transplant produced as float system. Therefore, seed germination and produced seedling health and diseases and pests management have high importance. So, evaluation of seeds dressing effect on germination and important pests and diseases management in the nursery for healthy transplantable seedling production is important. The study aims to investigate the effect of disinfectant of K326 tobacco seed on germination and percentage of transmissible transplants and management of contamination of sciaridae fly, aphid, and collar rot in a float system tray.
Material and method: This study was conducted as a completely randomized design in 3 replications at Tirtash Research and Education Center in 2014. seeds dressed by pelleting apparatus disinfected with Metalaxyl (Ridomil) and Thiophanate–methyl (TopsinM) fungicides and Imidacloprid (Gaucho), Thiamethoxam (Confidor) and Thiodicarb (Larvin) insecticide and seeds heating by 60ºC temperature warm air during 1 hour, seeds treatment by 50ºC heat water for 10 minutes and treatment by 0.5 percent concentration sodium hypochlorite for 4 minutes. Then normal seedlings percent by standard germination test, seedling emergence percent in float system, transplantable seedling of float system and infected to Sciarid fly, aphid and stem rot seedlings determined.
Results: Results showed that K326 Tobacco Seeds Disinfected by 2.5 g/kg metallaxyl + 2.5 g/kg thiophane-methyl (70% wettable powder) + 10 g/kg imidacloprid + 6 cm3/kg Thiodicarb had the highest percentage of normal seedlings, percentage of seedling emergence in the float system tray and percentage of removable transplants and the least seedling contaminated with sciaridae, aphid and collar rot.
Conclusion: Results of this study showed that all seed disinfection treatments improved seed germination, seedling emergence percentage, and removable seedlings in the float system tray as well as infected seedlings compared to control decreased collar rot, sciaridae fly, and aphids. Also, the mentioned traits were superior to the non-chemical disinfectant treatments in seed disinfection treatments with the studied fungicides and insecticides.
Highlights:
1- The effects of chemical disinfectant treatments (different insecticides and fungicides permitted and common) as coatings on seed germination and percentage of tobacco seedling emergence were evaluated and compared.
ed The effect of non-chemical disinfectant treatments on seed germination and percentage of tobacco seedling emergence and management of pests and diseases seedbed were evaluated and compared.
Hossein Rezvani, Seyyed Fazel Fazeli Kakhki,
Volume 7, Issue 2 (3-2021)
Volume 7, Issue 2 (3-2021)
Abstract
Extended Abstract
Introduction: One of the biological methods of weed control is the use of allelopathic substances or herbal secretions that have the potential to inhibit growth weeds. Wheat allelopathic studies include the study of wheat allelopathy against other crops, weeds, pests and diseases, isolation and identification of allelopathic compounds, the effects of wheat toxicity on self-storage and management of wheat residues. Wild mustard (Sinapis arvensis) is a problematic weed in the country, especially in Golestan province. The present study was conducted to investigate the allelopathic potential of four wheat cultivars to use those cultivars in integrated weed management system to reduction growth mustard weed.
Materials and methods: A factorial experiment was conducted in completely randomized design with three replications at Physiology Laboratory of Golestan Agricultural Research Center. Treatments included concentrations of 0, 2.5, 5, and 7.5% aqueous extract of aerial and underground organs of four wheat cultivars (Morvarid, Moghan, Tajan, and Arta) with 6000 polyethylene glycol treatment in four concentration (zero, 2.5, 5, and 7.5 percent). Three-parameter logistic model was used to evaluate the allelopathic potential of wheat genotypes for reducing the percentage of wild mustard germination and liquid chromatography (HPLC) was used to determine the phenolic acids composition in wheat cultivar extract.
Results: Extract of shoot of all wheat cultivars reduced root length of wild mustard in comparison of control. Wheat cultivars reduced shoot length of wild mustard by 28% to 51% compared to control. The highest reduction in mustard shoot length was obtained from the Morvarid extract. Increase in shoot extract concentration of Arta to 7.5%, reduced root and shoot dry weight as 47 and 29% in compare of control treatment and Moghan cultivar in the same concentration (7.5%) caused reduction in root and shoot dry weight with 68 and 41% respectively. The highest reduction in germination indices of wild mustard was obtained from high concentrations of Morvarid and Moghan wheat extract. It was also found that with increasing concentration of polyethylene glycol (PEG) growth indices and germination components of wild mustard seed decreased, but this decrease was not significant. This confirms that the osmotic potential of the extract concentration is not involved in the exacerbation of the allelochemical effect and the likelihood of osmotic effect seems poor. In total, Morvarid cultivar with 25.34 mg phenolic acid content had the highest phenolic acid concentration, which was approximately three times more than that of Tajan, 1.5 times Moghan and three times of Arta cultivar. Morvarid cultivar had higher concentration of vanillic acid and ferulic acid than the other three cultivars. Overall, the least allelopathic effect was observed in Tajan cultivar and the most allelopathic effect was in Morvarid cultivar.
Conclusion: Among the cultivars studied, the highest inhibition was related to Morvarid cultivar. The results also showed that the highest amount of inhibition was related to shoot extract so that the root extract inhibition was less than the shoot on studied traits. In general, the results of the present study showed that some wheat cultivars have greater inhibitory potential against wild mustard weed, which can be used in breeding programs to produce cultivar with high allelopathic potential. Awareness of this issue is more important, especially in sustainable weed-management. Therefore, it is suitable to perform comprehensive studies on their allelopathic potential so that they can be used in agriculture, including combating with weeds, pests and plant diseases, breeding crop and horticulture, design herbicides and pesticides that is provide environmentally friendly, safe, and biodegradable.
Highlights:
Introduction: One of the biological methods of weed control is the use of allelopathic substances or herbal secretions that have the potential to inhibit growth weeds. Wheat allelopathic studies include the study of wheat allelopathy against other crops, weeds, pests and diseases, isolation and identification of allelopathic compounds, the effects of wheat toxicity on self-storage and management of wheat residues. Wild mustard (Sinapis arvensis) is a problematic weed in the country, especially in Golestan province. The present study was conducted to investigate the allelopathic potential of four wheat cultivars to use those cultivars in integrated weed management system to reduction growth mustard weed.
Materials and methods: A factorial experiment was conducted in completely randomized design with three replications at Physiology Laboratory of Golestan Agricultural Research Center. Treatments included concentrations of 0, 2.5, 5, and 7.5% aqueous extract of aerial and underground organs of four wheat cultivars (Morvarid, Moghan, Tajan, and Arta) with 6000 polyethylene glycol treatment in four concentration (zero, 2.5, 5, and 7.5 percent). Three-parameter logistic model was used to evaluate the allelopathic potential of wheat genotypes for reducing the percentage of wild mustard germination and liquid chromatography (HPLC) was used to determine the phenolic acids composition in wheat cultivar extract.
Results: Extract of shoot of all wheat cultivars reduced root length of wild mustard in comparison of control. Wheat cultivars reduced shoot length of wild mustard by 28% to 51% compared to control. The highest reduction in mustard shoot length was obtained from the Morvarid extract. Increase in shoot extract concentration of Arta to 7.5%, reduced root and shoot dry weight as 47 and 29% in compare of control treatment and Moghan cultivar in the same concentration (7.5%) caused reduction in root and shoot dry weight with 68 and 41% respectively. The highest reduction in germination indices of wild mustard was obtained from high concentrations of Morvarid and Moghan wheat extract. It was also found that with increasing concentration of polyethylene glycol (PEG) growth indices and germination components of wild mustard seed decreased, but this decrease was not significant. This confirms that the osmotic potential of the extract concentration is not involved in the exacerbation of the allelochemical effect and the likelihood of osmotic effect seems poor. In total, Morvarid cultivar with 25.34 mg phenolic acid content had the highest phenolic acid concentration, which was approximately three times more than that of Tajan, 1.5 times Moghan and three times of Arta cultivar. Morvarid cultivar had higher concentration of vanillic acid and ferulic acid than the other three cultivars. Overall, the least allelopathic effect was observed in Tajan cultivar and the most allelopathic effect was in Morvarid cultivar.
Conclusion: Among the cultivars studied, the highest inhibition was related to Morvarid cultivar. The results also showed that the highest amount of inhibition was related to shoot extract so that the root extract inhibition was less than the shoot on studied traits. In general, the results of the present study showed that some wheat cultivars have greater inhibitory potential against wild mustard weed, which can be used in breeding programs to produce cultivar with high allelopathic potential. Awareness of this issue is more important, especially in sustainable weed-management. Therefore, it is suitable to perform comprehensive studies on their allelopathic potential so that they can be used in agriculture, including combating with weeds, pests and plant diseases, breeding crop and horticulture, design herbicides and pesticides that is provide environmentally friendly, safe, and biodegradable.
Highlights:
- The allelopathic potential of wheat cultivars was investigated on germination of wild mustard seeds.
- High performance liquid chromatography was used to detect inhibitors and other allopathic substances of wheat cultivars.
- Biological inhibition was investigation in wild mustard weed.
Rahim Tarbali, Ali Asghar Aliloo, Manouchehr Farjami Nejad,
Volume 7, Issue 2 (3-2021)
Volume 7, Issue 2 (3-2021)
Abstract
Extended Abstract
Introduction: The weed invasion is one of the main yield-reducing factors in crops. They are potent competitors on vital resources which limits the availability of the resources for crops. Allelopathy is one of the weeds' abilities that commonly with inhibitory influences, affects plant communities' behavior. Therefore, the evaluation of these compounds' effects is important on crop plants. Also, the identification of allelopathic plants and their bioactive compounds can be a suitable approach to weed management. Thus, the aim of this study was the evaluation of the allelopathic potential of C. falcate on germination indices of wheat seeds and the mode of action of the extract on some enzyme activities. Furthermore, secondary metabolites in methanolic root extract were identified and reported.
Materials and methods: Germination and seedling experiments of Triticum aestivum var. Sardary seeds were tested by 0, 5%, 10%, 15%, and 20% concentrations of C. falcata root extracts based on CRD with four replications at the research laboratory of Maragheh University during 2018-19. Also, the influence of the extract was studied on enzyme activities of alpha-amylase, catalase, peroxidase, superoxide dismutase, and polyphenol oxidase. Furthermore, chemical compounds of the root methanolic extract identified by GC/MS instruments.
Results: Germination percentage and germination rate decreased significantly with the increase in the concentration of the extract, and germination stopped at concentrations above 15%. The results of seedling growth showed severe inhibitory effects of the extract on radicle and shoot organs of wheat seedlings that associated with reducing of the lengths and weights of the organs, and consequently, the vigor of seedling declined. The extract significantly reduced the activity of alpha-amylase, however, the activities of antioxidant enzymes first increased at low and medium concentrations but at high concentrations, the activities declined. The phytochemical analysis identified 62 compounds in the root of this plant that Octadecatrienal, Dihydro-4H-pyrazolo [3, 4-d] pyrimidin-4-one, Hexadecanoic acid, Hexadecanoic acid, 2-hydroxy-1 (hydroxymethyl) ethyl ester, Isopropyl isothiocyanate, and Cyclohexanone could be effective compounds on seed germination.
Introduction: The weed invasion is one of the main yield-reducing factors in crops. They are potent competitors on vital resources which limits the availability of the resources for crops. Allelopathy is one of the weeds' abilities that commonly with inhibitory influences, affects plant communities' behavior. Therefore, the evaluation of these compounds' effects is important on crop plants. Also, the identification of allelopathic plants and their bioactive compounds can be a suitable approach to weed management. Thus, the aim of this study was the evaluation of the allelopathic potential of C. falcate on germination indices of wheat seeds and the mode of action of the extract on some enzyme activities. Furthermore, secondary metabolites in methanolic root extract were identified and reported.
Materials and methods: Germination and seedling experiments of Triticum aestivum var. Sardary seeds were tested by 0, 5%, 10%, 15%, and 20% concentrations of C. falcata root extracts based on CRD with four replications at the research laboratory of Maragheh University during 2018-19. Also, the influence of the extract was studied on enzyme activities of alpha-amylase, catalase, peroxidase, superoxide dismutase, and polyphenol oxidase. Furthermore, chemical compounds of the root methanolic extract identified by GC/MS instruments.
Results: Germination percentage and germination rate decreased significantly with the increase in the concentration of the extract, and germination stopped at concentrations above 15%. The results of seedling growth showed severe inhibitory effects of the extract on radicle and shoot organs of wheat seedlings that associated with reducing of the lengths and weights of the organs, and consequently, the vigor of seedling declined. The extract significantly reduced the activity of alpha-amylase, however, the activities of antioxidant enzymes first increased at low and medium concentrations but at high concentrations, the activities declined. The phytochemical analysis identified 62 compounds in the root of this plant that Octadecatrienal, Dihydro-4H-pyrazolo [3, 4-d] pyrimidin-4-one, Hexadecanoic acid, Hexadecanoic acid, 2-hydroxy-1 (hydroxymethyl) ethyl ester, Isopropyl isothiocyanate, and Cyclohexanone could be effective compounds on seed germination.
Conclusion: C. falcata had a very strong inhibitory effect on the seed viability and seed vigor of the wheat seeds. According to the results, the mode of action of the allelopathic compounds is induced by induction of oxidative stress and inhibition of seed reserves remobilization during germination. The high sensitivity of alpha-amylase activity to allelochemicals was detected in this experiment. The decrease in the activity of all studied enzymes at high concentrations of C. falcata root extract was also significant. Stearic acid and palmitic acid derivatives accounted for about 30% of the compounds, which are very likely to interfere with the activity of the enzymes.
Highlights:
- Allelopathy effects of C. falcata root extract on germination indices of wheat were studied.
- Chemical compounds identified were in methanol extract of the plant roots of C. falcate.
- Oxidative stress is induced by the allelochemicals of C. falcata.
Amin Haghighi, Yazdan Izady, Miad Haji Mahmoudi, Seyed Amir Moosavi,
Volume 7, Issue 2 (3-2021)
Volume 7, Issue 2 (3-2021)
Abstract
Extended Abstract
Introduction: Seed germination and seedling emergence depend on the genetics of plant species and are also influenced by environmental factors. Genetics and nutritional status of the maternal plant, maturity stage at a time of harvest, and environmental factors such as temperature, salinity, drought, and soil fertility influence seed germination. Seed vigor as the main parameter of seed quality decreases due to accelerated aging and storage. The objective of this study was to evaluate the response of accelerated aged Chia seed to different levels of salinity stress.
Material and Methods: Two-way factorial experiment with experimental factors, including five levels of seed accelerated aging durations (0, 24, 48, 72, 96 h) and six levels of salinity stress (0, 50, 100, 150, 200, and 250 mM) was arranged based on a complete randomized block design with three replications. The experiment was conducted at seed technology laboratory Khuzestan Agricultural Sciences and Natural Resources, University of Khuzestan, in 2019.
Results: Results of analysis of variance revealed that the effect of seed accelerating aging, salinity stress, and interaction effects of both factors on all measured germination traits were significant (p<0.01). The best pattern of seed germination was evaluated using three-parameter sigmoid models (logistic, Gompertz, and sigmoidal) and two polynomial models (quadratic and cubic), then the performance of all models was compared using (R2adj), root square of the mean (RMSE) and corrected Akaike index (AICc). Results showed that at accelerated aging duration, models' performance to describe Chia seed germination response varied at different levels of salinity stress. At no aging and 72h of accelerated aging treatments, the sigmoidal model exhibited the best fit on final seed germination, whereas for the other levels of accelerated aging, Gompertz exhibited the best fit. Based on the output of the sigmoidal model, for no aging and 72 hours of accelerated aging, 50% of seed germination was declined at 171.7 and 76.9 mM, respectively, and based on the results of the Gompertz model, after 24 and 48 h of accelerated aging, seed germination declined to 50% at 163.8 and 129.6 mM. Results obtained from fitting polynomial models on seed germination showed that the cubic model provides reasonable descriptions for studied traits such as seed vigor.
Conclusion: Chia seed germination was sensitive to salinity and accelerated aging treatments. At no aging condition, Chia seeds tolerate salinity stress up to 200 mM and were able to germinate. By increasing aging durations, seed germination declined dramatically at all salinity levels and after 96 hours of aging, there was no seed germination at 150 mM.
Highlights:
1- The best nonlinear model to study accelerated Chia seed response to salinity stress was selected using the model selection criterion.
2- Chia seed germination threshold to salinity stress was determined for not- aged and aged seeds.
Introduction: Seed germination and seedling emergence depend on the genetics of plant species and are also influenced by environmental factors. Genetics and nutritional status of the maternal plant, maturity stage at a time of harvest, and environmental factors such as temperature, salinity, drought, and soil fertility influence seed germination. Seed vigor as the main parameter of seed quality decreases due to accelerated aging and storage. The objective of this study was to evaluate the response of accelerated aged Chia seed to different levels of salinity stress.
Material and Methods: Two-way factorial experiment with experimental factors, including five levels of seed accelerated aging durations (0, 24, 48, 72, 96 h) and six levels of salinity stress (0, 50, 100, 150, 200, and 250 mM) was arranged based on a complete randomized block design with three replications. The experiment was conducted at seed technology laboratory Khuzestan Agricultural Sciences and Natural Resources, University of Khuzestan, in 2019.
Results: Results of analysis of variance revealed that the effect of seed accelerating aging, salinity stress, and interaction effects of both factors on all measured germination traits were significant (p<0.01). The best pattern of seed germination was evaluated using three-parameter sigmoid models (logistic, Gompertz, and sigmoidal) and two polynomial models (quadratic and cubic), then the performance of all models was compared using (R2adj), root square of the mean (RMSE) and corrected Akaike index (AICc). Results showed that at accelerated aging duration, models' performance to describe Chia seed germination response varied at different levels of salinity stress. At no aging and 72h of accelerated aging treatments, the sigmoidal model exhibited the best fit on final seed germination, whereas for the other levels of accelerated aging, Gompertz exhibited the best fit. Based on the output of the sigmoidal model, for no aging and 72 hours of accelerated aging, 50% of seed germination was declined at 171.7 and 76.9 mM, respectively, and based on the results of the Gompertz model, after 24 and 48 h of accelerated aging, seed germination declined to 50% at 163.8 and 129.6 mM. Results obtained from fitting polynomial models on seed germination showed that the cubic model provides reasonable descriptions for studied traits such as seed vigor.
Conclusion: Chia seed germination was sensitive to salinity and accelerated aging treatments. At no aging condition, Chia seeds tolerate salinity stress up to 200 mM and were able to germinate. By increasing aging durations, seed germination declined dramatically at all salinity levels and after 96 hours of aging, there was no seed germination at 150 mM.
Highlights:
1- The best nonlinear model to study accelerated Chia seed response to salinity stress was selected using the model selection criterion.
2- Chia seed germination threshold to salinity stress was determined for not- aged and aged seeds.
Ahmad Zare, Elham Elahifard, Zahra Asadinejad,
Volume 7, Issue 2 (3-2021)
Volume 7, Issue 2 (3-2021)
Abstract
Extended Abstract
Introduction: Syrian mesquite is introduced as a weed in wheat and barley fields, saffron, cotton and vegetables, and in orchards. The spread of this weed in different climates raises the question of how much native plant conditions can affect germination characteristics. Therefore, the purpose of this study was to evaluate the effect of native plant conditions on germination characteristics in response to environmental stresses (temperature, salinity, and drought).
Materials and Methods: To investigate dormancy elimination and germination response thresholds of two Syrian mesquite ecotypes (Khuzestan and Fars) to environmental factors (temperature, salinity, and drought), four separate experiments were carried out as factorial based on completely block design with three replications at Agricultural Sciences and Natural Resources University of Khuzestan. Treatments included immersion the seeds with concentrated sulfuric acid (96%) (0, 10, 15, 20, 25, and 30 min), different temperature (0, 5, 10, 15, 20, 25, 30, 35, 40, and 45 °C), salinity levels (0, 100, 200, 300, 400, 500, and 600 mM), and different levels of drought stress (0, 0.2, 0.4, 0.6, 0.8, 1 and 1.2 MPa).
Results: The time required for immersion of seeds in sulfuric acid to dormancy breaking for two ecotypes was different. The estimated parameters indicated time of immersion in sulfuric acid to reach 50% germination in the Khuzestan ecotype (11.38 min) was longer than the Fars ecotype (8.10 min). The Khuzestan ecotype was also able to germinate (45%) at 40 ° C, whereas germination in the Fars ecotype was stopped at this temperature. Germination rate and cumulative germination percentage at temperatures below 25 ° C were higher in Fars ecotype than in the Khuzestan ecotype. The results of the salinity experiment showed that 50% reduction in seed vigor index, final germination percentage, and germination rate in the Fars ecotype were 167.48, 404.46, and 307.02 mM respectively and in the Khuzestan ecotype were 0.89. 229, 380.16, and 299.57 mM, respectively. For drought treatments, 50% reduction in final germination percentage, seed vigor index, and germination rate in Fars ecotype were -0.50, -0.38, and -0.39 MPa, respectively, and in Khuzestan ecotype were -0.46, -0.46, and -0.50 MPa, respectively.
Conclusion: Overall, the results showed that native plant climatic conditions (latitude and longitude, elevation, rainfall, and temperature) can affect the degree of seed dormancy, resistance to environmental stresses such as temperature, salinity, and drought.
Highlights:
1- Seed germination response thresholds of two ecotypes of Fars and Khuzestan for exposure to temperature and drought and salinity stresses were compared.
Marjan Diyanat, Pouya Sonboli-Hamedani, Fereidoon Ghasem-Khan Ghajar,
Volume 8, Issue 1 (9-2021)
Volume 8, Issue 1 (9-2021)
Abstract
Extended Abstract
Introduction: Seed dormancy is the most important factor that prevents weed seed germination. Lack of simultaneous germination of weed seeds causes a number of problems in their control due to seed dormancy in the fields; therefore, weed seed dormancy is considered to be an undesirable trait for farmers. The aim of this study was to investigate the effect of magnetic field on seed dormancy elimination in some weed species.
Material and Methods: In order to study the effect of Magnetic field on germination and seedling growth of redroot pigweed (Amaranthus retroflexus), spring wild oat (Avena fatua) and common purslane (Portulaca oleraceae), a factorial experiment based on completely randomized design was conducted at the Ecology laboratory of Science Research Branch, Islamic Azad University in 2019. Factors consisted of dormancy breaking treatment at 8 levels (gibberellic acid 1000 mg/l for 20 minutes, gibberellic acid 2000 mg/l for 20 minutes, sulfuric acid for 5 minutes, sulfuric acid for 10 minutes, sulfuric acid for 20 minutes, nitrate potassium at 0.01 g/L, nitrate potassium at 0.05 g/L and control) and magnetic field at 4 levels (0, 25, 50 and 100 mT).
Results: Results showed that responses of three weed species to magnetic field were different. Magnetic field increased percentage of germination, fresh weight of plumule and length of plumule of redroot pigweed, so magnetic field at 100 mT was the best treatment for dormancy breaking. The highest germination percentage of wild oat was obtained in 0.01 mM potassium nitrate at 50 mT. The length plumule of wild oat increased significantly at 2000 mg/l gibberellic acid with increasing magnetic field level from zero to 25 mM. Nitrate potassium at 0.05 g/L was the best treatment for breaking the dormancy of common purslane. Magnetic field at 100 mT could increase percentage of germination of this weed.
Conclusion: In general, the results of this study showed that sulfuric acid treatment was not a suitable option for the removal of dormancy in the three weed species because of the elimination of seed embryos. Magnetic field treatment significantly increased the studied traits in all three species of redroot pigweed, spring wild oat and purslane. The interaction between dormancy breaking treatment and magnetic field was significant in many of the studied traits and the effect of dormancy breaking treatment was intensified by magnetic field. Therefore, the use of magnetic field treatment is recommended to increase the germination of these three species.
Highlights:
1- There is a positive and significant interaction between seed dormancy elimination treatments and magnetic field.
2- Sulfuric acid treatment is not a suitable option for breaking the dormancy of redroot pigweed, spring wild oat and purslane.
Introduction: Seed dormancy is the most important factor that prevents weed seed germination. Lack of simultaneous germination of weed seeds causes a number of problems in their control due to seed dormancy in the fields; therefore, weed seed dormancy is considered to be an undesirable trait for farmers. The aim of this study was to investigate the effect of magnetic field on seed dormancy elimination in some weed species.
Material and Methods: In order to study the effect of Magnetic field on germination and seedling growth of redroot pigweed (Amaranthus retroflexus), spring wild oat (Avena fatua) and common purslane (Portulaca oleraceae), a factorial experiment based on completely randomized design was conducted at the Ecology laboratory of Science Research Branch, Islamic Azad University in 2019. Factors consisted of dormancy breaking treatment at 8 levels (gibberellic acid 1000 mg/l for 20 minutes, gibberellic acid 2000 mg/l for 20 minutes, sulfuric acid for 5 minutes, sulfuric acid for 10 minutes, sulfuric acid for 20 minutes, nitrate potassium at 0.01 g/L, nitrate potassium at 0.05 g/L and control) and magnetic field at 4 levels (0, 25, 50 and 100 mT).
Results: Results showed that responses of three weed species to magnetic field were different. Magnetic field increased percentage of germination, fresh weight of plumule and length of plumule of redroot pigweed, so magnetic field at 100 mT was the best treatment for dormancy breaking. The highest germination percentage of wild oat was obtained in 0.01 mM potassium nitrate at 50 mT. The length plumule of wild oat increased significantly at 2000 mg/l gibberellic acid with increasing magnetic field level from zero to 25 mM. Nitrate potassium at 0.05 g/L was the best treatment for breaking the dormancy of common purslane. Magnetic field at 100 mT could increase percentage of germination of this weed.
Conclusion: In general, the results of this study showed that sulfuric acid treatment was not a suitable option for the removal of dormancy in the three weed species because of the elimination of seed embryos. Magnetic field treatment significantly increased the studied traits in all three species of redroot pigweed, spring wild oat and purslane. The interaction between dormancy breaking treatment and magnetic field was significant in many of the studied traits and the effect of dormancy breaking treatment was intensified by magnetic field. Therefore, the use of magnetic field treatment is recommended to increase the germination of these three species.
Highlights:
1- There is a positive and significant interaction between seed dormancy elimination treatments and magnetic field.
2- Sulfuric acid treatment is not a suitable option for breaking the dormancy of redroot pigweed, spring wild oat and purslane.
Mehrdad Mahlooji, Mehrdad Jenab,
Volume 8, Issue 1 (9-2021)
Volume 8, Issue 1 (9-2021)
Abstract
Extended abstract
Introduction: Barley is the fourth largest cereal crop in the world and the second cereal crop in Iran in supplying food needs. Considering population growth and food shortages, it is important to look at ways to increase production. Seeds of higher quality and vigor emerge better when exposed to biotic and abiotic stresses and have stronger seedlings with higher vigor. It seems that one of the appropriate strategies for reducing or moderating the effect of stress on yield is foliar application with micronutrients which can also affect germination and vigor of the produced seeds. For this purpose, the effect of water stress and foliar application on germination characteristics and vigor of barley seeds was investigated.
Materials and Methods: A factorial experiment was carried out based on CRD with four replications on the seeds resulted from a field experiment at Isfahan Kaboutarabad Agricultural Research Station, during the cropping year of 2018-19. The main factors was foliar application at five levels: no foliar application(water use), zinc sulfate (0.5%), potassium sulfate (0.5%) and salicylic acid (1.5 mM), and superoxide dismutase (3 mg/liter) at the start of tillering for three times at seven day intervals and the sub-factor was genotypes was Goharan (drought tolerant), Mehr (salt-tolerant) and Armaghan (stress-sensitive). After harvesting, germination traits were evaluated.
Results: Foliar application of maternal barley plant at the late season drought stress had a significant effect on root and shoots length, root and shoot dry weight, length and weight vigor indices, allometric coefficient and germination uniformity of seed. Also among the studied cultivars in late season irrigation cut off conditions, Goharan cultivar had a better shoot and root development (seedling vigor weight index) and higher seed germination uniformity.
Conclusion: Foliar application of potassium sulfate and zinc sulfate on different barley cultivars resulted in favorable metabolic conditions in seed and due to better root development and higher dry weight than stem development and as a result, higher allometric coefficient and better establishment under late season drought stress, may provide better growth conditions under drought stress conditions.
Highlights:
Introduction: Barley is the fourth largest cereal crop in the world and the second cereal crop in Iran in supplying food needs. Considering population growth and food shortages, it is important to look at ways to increase production. Seeds of higher quality and vigor emerge better when exposed to biotic and abiotic stresses and have stronger seedlings with higher vigor. It seems that one of the appropriate strategies for reducing or moderating the effect of stress on yield is foliar application with micronutrients which can also affect germination and vigor of the produced seeds. For this purpose, the effect of water stress and foliar application on germination characteristics and vigor of barley seeds was investigated.
Materials and Methods: A factorial experiment was carried out based on CRD with four replications on the seeds resulted from a field experiment at Isfahan Kaboutarabad Agricultural Research Station, during the cropping year of 2018-19. The main factors was foliar application at five levels: no foliar application(water use), zinc sulfate (0.5%), potassium sulfate (0.5%) and salicylic acid (1.5 mM), and superoxide dismutase (3 mg/liter) at the start of tillering for three times at seven day intervals and the sub-factor was genotypes was Goharan (drought tolerant), Mehr (salt-tolerant) and Armaghan (stress-sensitive). After harvesting, germination traits were evaluated.
Results: Foliar application of maternal barley plant at the late season drought stress had a significant effect on root and shoots length, root and shoot dry weight, length and weight vigor indices, allometric coefficient and germination uniformity of seed. Also among the studied cultivars in late season irrigation cut off conditions, Goharan cultivar had a better shoot and root development (seedling vigor weight index) and higher seed germination uniformity.
Conclusion: Foliar application of potassium sulfate and zinc sulfate on different barley cultivars resulted in favorable metabolic conditions in seed and due to better root development and higher dry weight than stem development and as a result, higher allometric coefficient and better establishment under late season drought stress, may provide better growth conditions under drought stress conditions.
- Goharan barley cultivar responds more positively to foliar application under late season drought stress conditions.
- Foliar application of potassium sulfate, zinc sulfate and super oxidase superoxide on Goharan cultivar maternal plant under late season drought stress condition led to the highest seedling root length, root dry weight and shoot dry weight.
Aidin Hamidi, Samad Allah Karami, Victoria Askari,
Volume 8, Issue 1 (9-2021)
Volume 8, Issue 1 (9-2021)
Abstract
Extended Abstract
Introduction: Cotton is the most important fiber-oil seed crop. Seed germination, vigour and health are the most important aspects of cotton seed quality. In Iran, annual cotton seed requirement is near 4000 tones, half of which is delinted and half is provided as fuzzy seed and therefore infection of fuzzy seeds to seed borne disease pathogens is possible. Every year a part of produced cotton seed does not possess standard quality and is not certify for various reasons including infection with seed borne disease pathogens. Thereafter, this research was conducted in order to study the relationship among cotton commercial cultivars seed germination, vigour and health.
Materials and Methods: Fuzzy seeds lots samples of Sahel, Varamin, Bakhtegan and Mehr cotton commercial cultivars with of 80, 90, and 95 percent intial germination ability (normal seedlings percent) produced at Golestan, Khorasan Razavi, Fars, and Ardabil provinces respectively underwent Standard germination and accelerated ageing tests. Final germination percent before and after accelerated ageing, normal seedlings percent after accelerated ageing, decayed seeds percent before and after accelerated ageing, mean germination time, seedling length, dry weight, seedling length and weight vigour indices after accelerated ageing were measured and the fungus on decayed seeds were determined by blotter test. Then, their average frequency was determined.
Results: Sahel and Bakhtegan cultivars and seeds having the highest primary germination ability had the most final germination percent before accelerated ageing and Sahel cultivar seed with the highest and moderate initial germination had the highest final germination percent after accelerated ageing. Sahel cultivar seeds had the highest normal seedlings percent after accelerated ageing. The highest decayed seeds percent before accelerated ageing belonged to Varamin and Mehr cultivars with moderate and low intial germination ability, and the highest decayed seeds percent after accelerated ageing belonged to Varamin and Mehr cultivars with low intial germination ability. Seeds having the lowest primary germination ability had the highest mean germination time and Sahel cultivar seeds had the highest seedling length and weight vigour indices. All studied cultivars seeds had been contaminated with Fusarium spp., Alternaria spp., Aspergillus spp. and Trichothecium roseum. Also, Varamin and Mehr cultivars seeds had the highest and Sahel cultivar seeds had the lowest average frequency of fungus on decayed seeds. Final germination percent before and after accelerated ageing and seedling length and weight vigour indices had significant negative correlation with decayed seeds percent before and after accelerated ageing.
Conclusion: Seeds decay was the most important factor of studied cotton cultivars seed deterioration and germination and seedling vigour decrease. Sahel and Mehr cultivars seeds and seeds with the highest (95 percent) and lowest (80 percent) intial germination ability seeds respectively had the highest (91 percent) and lowest (58 percent) seed final germination percent and seedling vigour. Alternaria spp., Aspergillus spp. on Mehr cultivar seeds, Fusarium spp. on Varamin cultivar seeds and Trichothecium roseum on Bakhtegan cultivars seeds with average frequency on decayed seeds after accelerated ageing of respectively 100, 99, 80.70 and 63 percent were the fungus that led to the most seeds germination and seedlings vigour decrease.
Highlights:
Introduction: Cotton is the most important fiber-oil seed crop. Seed germination, vigour and health are the most important aspects of cotton seed quality. In Iran, annual cotton seed requirement is near 4000 tones, half of which is delinted and half is provided as fuzzy seed and therefore infection of fuzzy seeds to seed borne disease pathogens is possible. Every year a part of produced cotton seed does not possess standard quality and is not certify for various reasons including infection with seed borne disease pathogens. Thereafter, this research was conducted in order to study the relationship among cotton commercial cultivars seed germination, vigour and health.
Materials and Methods: Fuzzy seeds lots samples of Sahel, Varamin, Bakhtegan and Mehr cotton commercial cultivars with of 80, 90, and 95 percent intial germination ability (normal seedlings percent) produced at Golestan, Khorasan Razavi, Fars, and Ardabil provinces respectively underwent Standard germination and accelerated ageing tests. Final germination percent before and after accelerated ageing, normal seedlings percent after accelerated ageing, decayed seeds percent before and after accelerated ageing, mean germination time, seedling length, dry weight, seedling length and weight vigour indices after accelerated ageing were measured and the fungus on decayed seeds were determined by blotter test. Then, their average frequency was determined.
Results: Sahel and Bakhtegan cultivars and seeds having the highest primary germination ability had the most final germination percent before accelerated ageing and Sahel cultivar seed with the highest and moderate initial germination had the highest final germination percent after accelerated ageing. Sahel cultivar seeds had the highest normal seedlings percent after accelerated ageing. The highest decayed seeds percent before accelerated ageing belonged to Varamin and Mehr cultivars with moderate and low intial germination ability, and the highest decayed seeds percent after accelerated ageing belonged to Varamin and Mehr cultivars with low intial germination ability. Seeds having the lowest primary germination ability had the highest mean germination time and Sahel cultivar seeds had the highest seedling length and weight vigour indices. All studied cultivars seeds had been contaminated with Fusarium spp., Alternaria spp., Aspergillus spp. and Trichothecium roseum. Also, Varamin and Mehr cultivars seeds had the highest and Sahel cultivar seeds had the lowest average frequency of fungus on decayed seeds. Final germination percent before and after accelerated ageing and seedling length and weight vigour indices had significant negative correlation with decayed seeds percent before and after accelerated ageing.
Conclusion: Seeds decay was the most important factor of studied cotton cultivars seed deterioration and germination and seedling vigour decrease. Sahel and Mehr cultivars seeds and seeds with the highest (95 percent) and lowest (80 percent) intial germination ability seeds respectively had the highest (91 percent) and lowest (58 percent) seed final germination percent and seedling vigour. Alternaria spp., Aspergillus spp. on Mehr cultivar seeds, Fusarium spp. on Varamin cultivar seeds and Trichothecium roseum on Bakhtegan cultivars seeds with average frequency on decayed seeds after accelerated ageing of respectively 100, 99, 80.70 and 63 percent were the fungus that led to the most seeds germination and seedlings vigour decrease.
Highlights:
- Cotton commercial cultivars seed lots seed borne fungi and contamination rate were identified.
The relationship of cotton commercial cultivars seeds germination percent and seedling vigour with contamination to seed borne fungi were determined
Ahmad Zare, Fatemeh Deris, Zahra Karimi,
Volume 8, Issue 1 (9-2021)
Volume 8, Issue 1 (9-2021)
Abstract
Extended Abstract
Introduction: Notobasis (Syrian Thistle (has been introduced as a weed - medicinal plant. In Khuzestan province, the presence of Notobasis is abundant in cereal fields, especially field margins. For successful weed control, knowledge of weed biology and ecology (temperature, salinity and drought stresses) plays a key role in population dynamics of weeds and weed management. Therefore, the study aimed to evaluate Syrian Thistle response to temperature, salinity and drought, as well as to determine the cardinal temperature based on segmented, beta-four-parameter and dent-like models.
Materials and Methods: To investigate the effect of temperature (5, 10, 15, 20, 25, 30, 35 and 40 °C), salinity (zero, 50, 100, 150, 200, 250 and 300 mM) and drought stress (zero, 2) -0.0, -0.4, -0.6, -0.8, -1, -1.2 and -1.4 MPa). Three separate experiments were conducted in 2019 at agricultural science and natural resources university of Khuzestan at the laboratory of weed science with 6 replications. In each Petri dish, 25 seeds were placed and 7 ml of solution was added. In salinity and drought stresses experiments, sodium chloride solution and polyethylene glycol 6000 were used.
Results: Germination of Notobasis at temperatures of 5-30°C was more than 90%, and germination percent decreased to 24% as the temperature increased to 35°C, Based on three models segmented, beta 4 parameter and Dent-like, the Base temperature was estimated 2.95, 2.01 and 0.67°C respectively. Also, the optimum temperature in two models (segmented and beta parameter) was obtained 22.26 and 23.40°C respectively. Ceiling temperature was predicted 40.57, 39.75 and 40.03°C in three models (segmented, beta 4 parameter and Dent- like). Salinity required to reduce 50% of germination percentage, germination rate, seedling length and seedling fresh weight were 152, 85, 151 and 127 mM. 50% reduction of traits such as germination percent, germination rate, seedling length and seedling fresh weight were -0.81, -0.41, -0.43 and -0.45 MPa of drought stress respectively.
Conclusion: The results indicated that Notobasis had germination in a wide range of temperatures (5-35°C). In response to environmental stress, Notobasis have been identified as a weed resistant to salinity and drought stresses. Therefore, the presence of this weed in saline fields and arid areas is not unexpected.
Highlights:
1-To determine of cardinal temperature of Notobasis based on different models.
2-To evaluate germination ecology of Notobasis to environmental factors (temperature, salinity and drought stress) as the first report.
Abbas Dehshiri, Mojtaba Karimi, Mohammadhasan Asareh, Aidin Hamidi, Zahra Karbalaeiharoftah, Fazlolla Safikhani,
Volume 8, Issue 1 (9-2021)
Volume 8, Issue 1 (9-2021)
Abstract
Extended abstract
Introduction: Small size of Satureja (Satureja hortensis L.) seed causes many problems in mechanized cultivation and its seed consumption is increased significantly. The approach discussed in the present study is the seed coating of Satureja by several matters and selecting the suitable method as well as investigation of adding hormonal and nutritional substances to the selected coating material for better emergence and the elimination of problem arise as a result of coating.
Materials and Methods: Purified Satureja seeds (97%) were prepared and poured into the coating machine at a specified amount. First, 1% solution of benomyl fungicide was sprayed on the seeds. Then some coating powder was sprayed on the spinning wet seeds inside the machine. Then some of the adhesive solution was sprayed on it and again the coating powder was added and this was repeated several times to create a suitable form for the coated seeds. This was repeated using different materials and among these coatings powder, vermiculite and perlite provided better coating on Satureja seed. Then, different materials including gibberellin, BAP, cytokinin, thiourea (CH4N2S) and potassium nitrate (KNO3), phosphorus from H2PO4 source and manganese sulfate (MnSO4) were used to the emergence of the enlarged seeds and also, the emergence of these seeds were evaluated in the greenhouse.
Results: Initial results showed that vermiculite and perlite provided better cover for Satureja compared with the other coating materials. Investigating the emergence of perlite-coated seeds in the greenhouse showed that gibberellin (all concentrations) and kinetin (500 mg/l) present in the seed coat improved the Satureja seed emergence under greenhouse condition. Also, it was found that Thiourea (700 and 7000 mg/l), potassium nitrate (7, 70, 700 mg/l), phosphorous (9 kg/100 kg seed) and manganese sulphate (2 and 4 mg/l) present in the coat significantly increased the Satureja seed emergence and led to improved seedling growth.
Conclusion: Perlite for the purpose of seed pelleting of Satureja showed good results and the use of gibberellin (at all concentrations) and quintine (500 mg/l) in the seed pelleting improved germination of pelleted Satureja seed.
Highlights:
1- Technical knowledge of Satureja seed pelleting was obtained.
2- The suitable material to improve the emergence of pelleted Satureja seed was introduced.
Introduction: Small size of Satureja (Satureja hortensis L.) seed causes many problems in mechanized cultivation and its seed consumption is increased significantly. The approach discussed in the present study is the seed coating of Satureja by several matters and selecting the suitable method as well as investigation of adding hormonal and nutritional substances to the selected coating material for better emergence and the elimination of problem arise as a result of coating.
Materials and Methods: Purified Satureja seeds (97%) were prepared and poured into the coating machine at a specified amount. First, 1% solution of benomyl fungicide was sprayed on the seeds. Then some coating powder was sprayed on the spinning wet seeds inside the machine. Then some of the adhesive solution was sprayed on it and again the coating powder was added and this was repeated several times to create a suitable form for the coated seeds. This was repeated using different materials and among these coatings powder, vermiculite and perlite provided better coating on Satureja seed. Then, different materials including gibberellin, BAP, cytokinin, thiourea (CH4N2S) and potassium nitrate (KNO3), phosphorus from H2PO4 source and manganese sulfate (MnSO4) were used to the emergence of the enlarged seeds and also, the emergence of these seeds were evaluated in the greenhouse.
Results: Initial results showed that vermiculite and perlite provided better cover for Satureja compared with the other coating materials. Investigating the emergence of perlite-coated seeds in the greenhouse showed that gibberellin (all concentrations) and kinetin (500 mg/l) present in the seed coat improved the Satureja seed emergence under greenhouse condition. Also, it was found that Thiourea (700 and 7000 mg/l), potassium nitrate (7, 70, 700 mg/l), phosphorous (9 kg/100 kg seed) and manganese sulphate (2 and 4 mg/l) present in the coat significantly increased the Satureja seed emergence and led to improved seedling growth.
Conclusion: Perlite for the purpose of seed pelleting of Satureja showed good results and the use of gibberellin (at all concentrations) and quintine (500 mg/l) in the seed pelleting improved germination of pelleted Satureja seed.
Highlights:
1- Technical knowledge of Satureja seed pelleting was obtained.
2- The suitable material to improve the emergence of pelleted Satureja seed was introduced.
Shamsaldin Skandarnejad, Manoochehr Gholipoor, Hassan Makarian,
Volume 8, Issue 2 (3-2022)
Volume 8, Issue 2 (3-2022)
Abstract
Extended Abstract
Introduction: A large number of experimental evidence indicates the positive effect of irradiating the seed with ultrasonic waves; so that irradiation causes the production of a more vigorous seedling. Conversely, inappropriate intensity and duration of irradiation can impose deleterious effects on seedlings by damaging the enzymatic activity. There are complex inter-and intra-relations between irradiation components (pre-soaking duration, temperature, and duration of irradiation) and response variables [seedling dry weight (SDW) and percent of abnormal seedlings (PAS)]. Therefore the balance values of the irradiation components cannot be precisely obtained by mean comparison. This study aimed to optimize (finding the balance values of) irradiation components for increased SDW, but diminished PAS of mung bean, using an artificial neural network.
Materials and Methods: A factorial experiment was conducted based on a completely randomized design with three replications. The factors were six pre-soaking durations (2, 4, 6, 8, 10, and 12 hours), 5 irradiation durations (0, 3, 6, 9 and 12 minutes), and 4 irradiation temperatures (17, 22, 27, and 32 oC). The 25 seeds were chosen for each petri dish. The multi-layer perceptron neural network was used to quantify the relations between variables; the experimental factors were used as the input (regressors), and PAS and SDW as the output of the model (response variables).
Results: The analysis of variance results indicated that the simple and interactive effects of factors were significant on PAS and SDW. The structure 3:3:2 of the neural network, which is based on Secant Hyperbolic function, was suitable. The SDW and PAS were negligibly different for the contribution of the factors in determining their changes. In terms of relative contribution, the factors ranked from higher to lower as irradiation duration, irradiation temperature, and pre-soaking duration. The optimized values of components of irradiation by the neural network were irradiation temperature of 17.96 oC, irradiation duration of 5.3 minutes, and pre-soaking duration of 11.25 hours. For these components, SDW was 27% higher, and PAS tended to be 0.6% lower, compared to the best component combination gotten by mean comparison.
Conclusion: Due to the highly strong interaction of irradiation components on seedling growth, the effect of component (s) tends to be changed intensively with changing the quantity of each component. In terms of finding the best combination of irradiation components, the neural network was more efficient than the mean comparison. Therefore, the neural network could be used as a complementary procedure in such investigations.
Highlights:
1- Irradiation components including irradiation duration and temperature, and pre-soaking duration affected seedling growth.
2- Inappropriate irradiation components diminished seedling growth to the below of no-irradiation conditions.
3- The optimum (balanced) levels of irradiation components increased seedling growth remarkably.
Kamran Alimardani, Amin Salehi, Mohsen Movahhedi Dehnavi, Ali Moradi,
Volume 8, Issue 2 (3-2022)
Volume 8, Issue 2 (3-2022)
Abstract
Extended Abstract
Introduction: Schrophularia striata is one of the medicinal plants of the Scrophulariaceae family and contains phenolic compounds. Locals have traditionally used this herbal medicine to treat infections caused by wounds, gastrointestinal diseases, and eye diseases. Due to excessive consumption by indigenous people and climate change, especially increasing temperature, the cold required to eliminate seed dormancy is not presently available and its germination and growth has decreased. Therefore, this plant is at the risk of extinction. Since this plant is propagated in natural habitats through seed and due to deep seed dormancy, evaluation of different seed dormancy methods is necessary for conservation and domestication of this species. In this study, suitable methods to eliminate seed dormancy of this plant using chilling and gibberellic acid treatments were studied on the seeds collected from different habitats of Ilam province.
Materials and Methods: To investigate the effect of using chilling and gibberellic acid on Schrophularia striata dormancy, a split plot factorial experiment based on completely randomized design with four replications was conducted at the seed laboratory of Yasouj University in 2018. The first factor included the duration of moist chilling period (0, 4, 8, 12 and 16 weeks), the second factor included gibberellic acid (0, 300 and 600 mg/L) and the third factor included five habitats (Ilam, Ivan, Mehran, Abadan and Dehloran).
Results: The results showed that the 16-week Chilling and zero gibberellic acid treatments had the highest germination percentage in all habitats, as the percentage of germination in Mehran, Ivan, Ilam, Abadan and Dehloran habitats was 66, 50, 36, 30 and 25%, respectively. Also, the highest germination rate was observed in all habitats at 16 weeks chilling and zero mg/L gibberellic acid concentration. The highest germination uniformity was obtained at 16 and 12 weeks of chilling.
Conclusions: Chilling period duration was effective on germination percentage and rate and with increasing chilling period, germination percentage and rate increased. This indicates that the seeds studied had some degree of physiological dormancy, and the seed of higher altitude habitats required longer chilling periods than those of the lower ones for germination. Also, according to the results of this experiment, chilling periods above 16 weeks should be used to increase germination percentage.
Highlights:
1- Chilling period duration in the presence of gibberellic acid was the most important factor for the elimination of Schrophularia striata seed Dormancy and increased germination.
2- With increasing altitude and in the same chilling period duration, habitats with lower altitude had higher germination percentage and rate
Introduction: Schrophularia striata is one of the medicinal plants of the Scrophulariaceae family and contains phenolic compounds. Locals have traditionally used this herbal medicine to treat infections caused by wounds, gastrointestinal diseases, and eye diseases. Due to excessive consumption by indigenous people and climate change, especially increasing temperature, the cold required to eliminate seed dormancy is not presently available and its germination and growth has decreased. Therefore, this plant is at the risk of extinction. Since this plant is propagated in natural habitats through seed and due to deep seed dormancy, evaluation of different seed dormancy methods is necessary for conservation and domestication of this species. In this study, suitable methods to eliminate seed dormancy of this plant using chilling and gibberellic acid treatments were studied on the seeds collected from different habitats of Ilam province.
Materials and Methods: To investigate the effect of using chilling and gibberellic acid on Schrophularia striata dormancy, a split plot factorial experiment based on completely randomized design with four replications was conducted at the seed laboratory of Yasouj University in 2018. The first factor included the duration of moist chilling period (0, 4, 8, 12 and 16 weeks), the second factor included gibberellic acid (0, 300 and 600 mg/L) and the third factor included five habitats (Ilam, Ivan, Mehran, Abadan and Dehloran).
Results: The results showed that the 16-week Chilling and zero gibberellic acid treatments had the highest germination percentage in all habitats, as the percentage of germination in Mehran, Ivan, Ilam, Abadan and Dehloran habitats was 66, 50, 36, 30 and 25%, respectively. Also, the highest germination rate was observed in all habitats at 16 weeks chilling and zero mg/L gibberellic acid concentration. The highest germination uniformity was obtained at 16 and 12 weeks of chilling.
Conclusions: Chilling period duration was effective on germination percentage and rate and with increasing chilling period, germination percentage and rate increased. This indicates that the seeds studied had some degree of physiological dormancy, and the seed of higher altitude habitats required longer chilling periods than those of the lower ones for germination. Also, according to the results of this experiment, chilling periods above 16 weeks should be used to increase germination percentage.
Highlights:
1- Chilling period duration in the presence of gibberellic acid was the most important factor for the elimination of Schrophularia striata seed Dormancy and increased germination.
2- With increasing altitude and in the same chilling period duration, habitats with lower altitude had higher germination percentage and rate
Behzad Nouri Feli, Hamid Reza Eisvand, Naser Akbari, Dariush Goodarzi,
Volume 8, Issue 2 (3-2022)
Volume 8, Issue 2 (3-2022)
Abstract
Extended Abstract
Introduction: Providing important and effective elements such as zinc and boron- especially in areas where the soil for some reason cannot meet the needs of the plant- will be a good solution to improve seed and seedling quality and nutrition, and community health status. A considerable part of the wheat producing regions in the country are faced with late season haet during seed development stages. Thus, the present study will investigate the effect of heat stress and mother plant nutrition with zinc and boron micronutrients on seed deterioration and physiological quality of wheat seedlings.
Material and Methods: In a field experiment, wheat seeds were planted on two suitable planting dates (November 20) and late (January 5) to apply late-season heat stress during the seed development stage with three replications in Ramhormoz, Iran. The nutrition of mother plants with zinc and boron elements was done at three levels (nutrient-free and application of zinc and boron) as a foliar application. After harvest, the seeds were transferred to the laboratory and membrane integrity of seed cells was investigated using an electrical conductivity test as an indicator of deterioration. Another part of the seeds was planted in a factorial pot experiment based on RCBD with three replications to evaluate the quality of seeds and seedlings in the greenhouse.
Results: The results showed that exposure of seeds to heat stress during development reduced seed quality as well as seedlings so that the cell membrane in the seeds produced under heat stress conditions was damaged and their electrical conductivity increased by 19%. Also, these seeds showed more sensitivity to deterioration. The percentage of seedling emergence in the stressed seeds decreased by 21.66%. Heat stress also reduced seedling quality indices such as chlorophyll content, shoot dry weight, and root dry weight. Application of zinc and boron on the mother plant not only led to improved quality of seeds and seedlings under normal conditions but also the negative effects of heat stress on seed and seedling quality were reduced. There was a significant negative correlation between the seed electrical conductivity test and qualitative parameters. Therefore, the use of this test is recommended to determine the quality of seeds, especially seeds produced under late-season heat stress conditions.
Conclusion: Noting the negative effect of heat during seed development on seed quality, planting dates should be adjusted as much as possible so that the seed development stage does not coincide with the late-season heat stress. Due to the beneficial effects of using zinc and boron in the mother plant on many traits related to the quality of seeds and seedlings, their application- especially zinc- in soils with deficiency or the possibility of heat stress at the end of the season is recommended.
Highlights:
Introduction: Providing important and effective elements such as zinc and boron- especially in areas where the soil for some reason cannot meet the needs of the plant- will be a good solution to improve seed and seedling quality and nutrition, and community health status. A considerable part of the wheat producing regions in the country are faced with late season haet during seed development stages. Thus, the present study will investigate the effect of heat stress and mother plant nutrition with zinc and boron micronutrients on seed deterioration and physiological quality of wheat seedlings.
Material and Methods: In a field experiment, wheat seeds were planted on two suitable planting dates (November 20) and late (January 5) to apply late-season heat stress during the seed development stage with three replications in Ramhormoz, Iran. The nutrition of mother plants with zinc and boron elements was done at three levels (nutrient-free and application of zinc and boron) as a foliar application. After harvest, the seeds were transferred to the laboratory and membrane integrity of seed cells was investigated using an electrical conductivity test as an indicator of deterioration. Another part of the seeds was planted in a factorial pot experiment based on RCBD with three replications to evaluate the quality of seeds and seedlings in the greenhouse.
Results: The results showed that exposure of seeds to heat stress during development reduced seed quality as well as seedlings so that the cell membrane in the seeds produced under heat stress conditions was damaged and their electrical conductivity increased by 19%. Also, these seeds showed more sensitivity to deterioration. The percentage of seedling emergence in the stressed seeds decreased by 21.66%. Heat stress also reduced seedling quality indices such as chlorophyll content, shoot dry weight, and root dry weight. Application of zinc and boron on the mother plant not only led to improved quality of seeds and seedlings under normal conditions but also the negative effects of heat stress on seed and seedling quality were reduced. There was a significant negative correlation between the seed electrical conductivity test and qualitative parameters. Therefore, the use of this test is recommended to determine the quality of seeds, especially seeds produced under late-season heat stress conditions.
Conclusion: Noting the negative effect of heat during seed development on seed quality, planting dates should be adjusted as much as possible so that the seed development stage does not coincide with the late-season heat stress. Due to the beneficial effects of using zinc and boron in the mother plant on many traits related to the quality of seeds and seedlings, their application- especially zinc- in soils with deficiency or the possibility of heat stress at the end of the season is recommended.
Highlights:
- Zinc and boron micronutrients were used to mitigate the harmful effects of heat stress on seed quality.
- Physiological characteristics of seedlings obtained from seeds produced in the field under late-season heat stress conditions were investigated.
Nader Shahbazi, Seyyed Kamal Kazemitabar, Ghaffar Kiani, Ali Pakdin Parizi, Pooyan Mehraban Joubani,
Volume 8, Issue 2 (3-2022)
Volume 8, Issue 2 (3-2022)
Abstract
Extended abstract
Introduction: One of the ways to overcome the limitation of fresh water and lack of sufficient water reserves for agriculture is to use unconventional waters such as seawater. Salinity stress is the most important abiotic stress in seawater application. Identification and planting of salinity tolerant genotypes of a plant species is one of the effective and valuable strategies in reducing the effects of salinity stress. Germination, growth and seedling establishment are among the salinity-sensitive stages in most plants. Therefore, for improvement of abiotic stress tolerance in plants, it is necessary to study the traits and indicators related to tolerance in the germination stage.
Material and Methods: A factorial experiment was conducted based on a completely randomized design with three replications at the laboratory of Plant Breeding Department of Sari University of Agricultural Sciences and Natural Resources in 2020. The first factor included the cultivars and the second included 5 salinity levels (control (no seawater), 3, 6, 9 and 11 dS (deciSiemens per meter) obtained from the incorporation of Caspian Sea and urban water. The number of germinated seeds was counted during eight days of salinity stress. Then, germination percentage, time required for 50% germination, seedling vigor index and germination rate were calculated. On the eighth day, radicle and plumule dry and fresg weights, radicle and plumule length and seedling dry weight were measured.
Results: The results of analysis of variance showed the significance of the effect of different salinity levels, genotype and the interaction of salinity and genotype for all calculated indices at p<0.01. Mean comparison of the interaction of different levels of salinity and cultivars and landraces showed that all the studied traits except for the time to reach fifty percent germination decreased with increasing salinity. Among the studied cultivars, Oltan cultivar had the highest value of germination percentage (100%), germination rate (24.17 seeds per day), seedling vigor index (5.03), plumule length (55.67 mm), radicle length (70 mm), plumule fresh weight (62 mg), radicle fresh weight (45 mg), plumule dry weight (4.77 mg), seedling dry weight (6/23 Mg) and the lowest amount of the time required for 50% germination (24.17 hours) in control treatment. In contrast, Pakistani cultivar had the lowest germination rate (3.06 seeds per day), seedling vigor index (1), plumule length (8.33 mm), radicle length (3 mm), plumule fresh weight (10 mg), radicle fresh weight (2 mg), plumule dry weight (0.57 mg), seedling dry weight (0.84 mg) and the highest time required for 50% germination (24.17 hours) in 11 dS / m salinity level. Using the results of this experiment, among the studied cultivars, Oltan cultivar was selected as the most tolerant and Pakistani cultivar as the most sensitive cultivars to salinity stress at the germination stage.
Conclusion: The studied cultivars and landraces showed different reactions in terms of germination indices when treated with salinity from seawater. The high significant difference in this experiment indicated the high genetic diversity among the studied genotypes. It is possible to choose from these genotypes for salinity tolerance breeding programs in sesame plant.
Highlights:
Introduction: One of the ways to overcome the limitation of fresh water and lack of sufficient water reserves for agriculture is to use unconventional waters such as seawater. Salinity stress is the most important abiotic stress in seawater application. Identification and planting of salinity tolerant genotypes of a plant species is one of the effective and valuable strategies in reducing the effects of salinity stress. Germination, growth and seedling establishment are among the salinity-sensitive stages in most plants. Therefore, for improvement of abiotic stress tolerance in plants, it is necessary to study the traits and indicators related to tolerance in the germination stage.
Material and Methods: A factorial experiment was conducted based on a completely randomized design with three replications at the laboratory of Plant Breeding Department of Sari University of Agricultural Sciences and Natural Resources in 2020. The first factor included the cultivars and the second included 5 salinity levels (control (no seawater), 3, 6, 9 and 11 dS (deciSiemens per meter) obtained from the incorporation of Caspian Sea and urban water. The number of germinated seeds was counted during eight days of salinity stress. Then, germination percentage, time required for 50% germination, seedling vigor index and germination rate were calculated. On the eighth day, radicle and plumule dry and fresg weights, radicle and plumule length and seedling dry weight were measured.
Results: The results of analysis of variance showed the significance of the effect of different salinity levels, genotype and the interaction of salinity and genotype for all calculated indices at p<0.01. Mean comparison of the interaction of different levels of salinity and cultivars and landraces showed that all the studied traits except for the time to reach fifty percent germination decreased with increasing salinity. Among the studied cultivars, Oltan cultivar had the highest value of germination percentage (100%), germination rate (24.17 seeds per day), seedling vigor index (5.03), plumule length (55.67 mm), radicle length (70 mm), plumule fresh weight (62 mg), radicle fresh weight (45 mg), plumule dry weight (4.77 mg), seedling dry weight (6/23 Mg) and the lowest amount of the time required for 50% germination (24.17 hours) in control treatment. In contrast, Pakistani cultivar had the lowest germination rate (3.06 seeds per day), seedling vigor index (1), plumule length (8.33 mm), radicle length (3 mm), plumule fresh weight (10 mg), radicle fresh weight (2 mg), plumule dry weight (0.57 mg), seedling dry weight (0.84 mg) and the highest time required for 50% germination (24.17 hours) in 11 dS / m salinity level. Using the results of this experiment, among the studied cultivars, Oltan cultivar was selected as the most tolerant and Pakistani cultivar as the most sensitive cultivars to salinity stress at the germination stage.
Conclusion: The studied cultivars and landraces showed different reactions in terms of germination indices when treated with salinity from seawater. The high significant difference in this experiment indicated the high genetic diversity among the studied genotypes. It is possible to choose from these genotypes for salinity tolerance breeding programs in sesame plant.
Highlights:
- Different sesame genotypes at different levels of sea salt salinity showed different response at germination stage.
- Among the cultivars studied, Oltan, Nazetakshakhe, Halil and Dashtashtan 2 showed a high degree of tolerance to salinity stress.
Mohammad Hossein Banakar, Hamzeh Amiri, Gholam Hassan Ranjbar, Mohammad Raza Sarafraz Ardakani,
Volume 8, Issue 2 (3-2022)
Volume 8, Issue 2 (3-2022)
Abstract
Extended Abstract
Introduction: Fenugreek, is a medicinal plant that has been considered as a salt tolerant crop. This research was conducted to investigate the effects of salt stress on seedling emergence characteristics and determination of the salt tolerance threshold, declivity of emergence and salt tolerance index of some fenugreek ecotypes.
Material and Methods: Seeds of five ecotypes (Ardestani, Isfahani, hendi, Mashhadi, Neyrizi) were subjected to seven levels of salinity (0.5, 3, 6, 9, 12, 15 and 18 dS/m) in a factorial experiment based on a completely randomized design with three replications. In this research, experimental models (linear, sigmoidal, exponential and multi-component) were used.
Results: Results showed that increasing levels of salinity decreased seedling emergence percentage and rate. In Ardestani and Isfahani ecotypes, increase of salinity up to 3 dS/m had no effect on seedling emergence percentage and thereafter, decreased it, significantly. The maximum seedling emergence percentage (94.62%) belonged to Hendi in control treatment. Hendi ecotype had also the highest emergence percentage (25.81%) at 18 dS/m. Although the highest seedling emergence rate (5.93 per day) belonged to Mashhadi ecotype in control treatment, it didn’t show any significant difference to Hendi, Neyrizi and Isfahani ecotypes. In Ardestani, Mashhadi and Neyrizi ecotypes, seedling length decreased significantly with increasing salinity, but this decrease was not significant in Isfahani ecotype between salinities of 3 and 6 dS/m and also 12 and 15 dS/m. In Hendi ecotype, seedling length at 3 dS/m was similar to control, but higher salinities caused a significant reduction. The maximum value of seedling vigor index (20.44) belonged to Mashhadi and Neyrizi ecotypes in control treatment and Ardestani ecotype had the lowest one (0.39) at 18 dS/m. Results showed that seedling dry weight was first unchanged up to salinity level of 3 dS/m and then gradually decreased with increasing salinity. In Hendi and Neyrizi ecotypes, applying salinities higher than 6 dS/m, gradually decreased seedling dry weight. The salt tolerance threshold of fenugreek for Ardestani, Isfahani, Hindi, Mashhadi and Neyrizi ecotypes was 4.69, 4.90, 7.83, 1.69 and 1.57 dS/m, respectively. Thus, the highest salt tolerance threshold (7.83 dS/m) and the declivity of emergence percentage (7.55%) was obtained from Hendi ecotype and the lowest one from Neyrizi ecotype (1.57 and 4.63 dS/m, respectively). Results of nonlinear models showed that the highest salinity in which 50 percent of seedlings emerged was obtained in Hendi ecotype (14.24 dS/m).
Conclusion: Based on the results, comparing the salt tolerance index of fenugreek ecotypes and also evaluating of some experimental models showed that Hendi ecotype may be introduced as the most tolerant ecotype to salinity stress at the emergence stage to exploit saline soil and water resources.
Highlights:
- Different fenugreek ecotypes in terms of salinity tolerance at seedling emergence stage were compared using some experimental models.
- The salt tolerance threshold, declivity of emergence and also salt tolerance index was reported for some fenugreek ecotypes.
Hakimeh Rahimi, Mohsen Malek, Farshid Ghaderi-Far,
Volume 8, Issue 2 (3-2022)
Volume 8, Issue 2 (3-2022)
Abstract
Extended Abstract
Introduction: Seeds need successful germination at the optimal time and conditions to survive. Sometimes, even in the best environmental and genetic conditions of the seed, they do not germinate or germinate with a delay, which are called dormant seeds. Seed dormancy can have positive effects on avoiding adverse conditions and ensuring survival in the environment. However, dormancy in crop plants reduces emergence and yield by preventing germination. A combination of environmental and seed genetic factors are involved in seed dormancy formation. In general, seed dormancy includes: physical dormancy, physiological dormancy, morphological dormancy, morphophysiological dormancy and combinational dormancy, and physical / chemical scarification treatments, hot and cold stratification, leaching, hormonal treatments, after-ripening, light and combination treatments can be used to eliminate dormancy depending on its type. Therefore, in this study, using domestic studies conducted in the field of seed dormancy in different plant species, identification of dormancy in different plant species and its types have been discussed, and general and practical information in this regard has been provided.
Materials and Methods: In this study, 168 reports published on 250 plant species in the last 20 years, which were published in the seed dormancy of medicinal plants, weeds, rangelands, ornamentals and crops were investigated. Then, the percentage of plants studied and their families, as well as the share of different types of seed dormancy and appropriate treatments to for its eliminate were determined.
Results: Among the plant species studied, the most freuqent type of dormancy was related to physiological dormancy (50%), followed by physical dormancy, combinational dormancy, morphophysiological dormancy and the lowest share of dormancy in the studied plant species was related to morphological dormancy (1.61%). The most effective treatments to eliminate physiological dormancy were the use of cold stratification, gibberellic acid, and potassium nitrate. Also, the most effective treatments for the removal of physical dormancy were the use of physical / mechanical scarification treatments, chemical scarification and potassium nitrate treatment. According to the results, temperature treatments and then gibberellic acid and potassium nitrate treatments are recommendedt eliminate morphological dormancy. To eliminate morphophysiological dormancy, it is recommended to use treatments to maturate differentiated small or undifferentiated seeds (removal of morphological dormancy) as well as treatments to counteract the germination inhibitory factors or to compensate the were applied the most to eliminate morphophysiological dormancy.
Conclusion: By identifying the type of dormancy and applying the appropriate treatments, the germination of economical and valuable plants can be improved.
Highlights:
1- Dormancy types in native plant species of Iran through the information of domestic studies was investigated and a comprehensive report on seed dormancy was presented for the first time.
2- General and practical information about seed dormancy, effective factors and methods of dormancy elimination was reviewed in a practical way.
Introduction: Seeds need successful germination at the optimal time and conditions to survive. Sometimes, even in the best environmental and genetic conditions of the seed, they do not germinate or germinate with a delay, which are called dormant seeds. Seed dormancy can have positive effects on avoiding adverse conditions and ensuring survival in the environment. However, dormancy in crop plants reduces emergence and yield by preventing germination. A combination of environmental and seed genetic factors are involved in seed dormancy formation. In general, seed dormancy includes: physical dormancy, physiological dormancy, morphological dormancy, morphophysiological dormancy and combinational dormancy, and physical / chemical scarification treatments, hot and cold stratification, leaching, hormonal treatments, after-ripening, light and combination treatments can be used to eliminate dormancy depending on its type. Therefore, in this study, using domestic studies conducted in the field of seed dormancy in different plant species, identification of dormancy in different plant species and its types have been discussed, and general and practical information in this regard has been provided.
Materials and Methods: In this study, 168 reports published on 250 plant species in the last 20 years, which were published in the seed dormancy of medicinal plants, weeds, rangelands, ornamentals and crops were investigated. Then, the percentage of plants studied and their families, as well as the share of different types of seed dormancy and appropriate treatments to for its eliminate were determined.
Results: Among the plant species studied, the most freuqent type of dormancy was related to physiological dormancy (50%), followed by physical dormancy, combinational dormancy, morphophysiological dormancy and the lowest share of dormancy in the studied plant species was related to morphological dormancy (1.61%). The most effective treatments to eliminate physiological dormancy were the use of cold stratification, gibberellic acid, and potassium nitrate. Also, the most effective treatments for the removal of physical dormancy were the use of physical / mechanical scarification treatments, chemical scarification and potassium nitrate treatment. According to the results, temperature treatments and then gibberellic acid and potassium nitrate treatments are recommendedt eliminate morphological dormancy. To eliminate morphophysiological dormancy, it is recommended to use treatments to maturate differentiated small or undifferentiated seeds (removal of morphological dormancy) as well as treatments to counteract the germination inhibitory factors or to compensate the were applied the most to eliminate morphophysiological dormancy.
Conclusion: By identifying the type of dormancy and applying the appropriate treatments, the germination of economical and valuable plants can be improved.
Highlights:
1- Dormancy types in native plant species of Iran through the information of domestic studies was investigated and a comprehensive report on seed dormancy was presented for the first time.
2- General and practical information about seed dormancy, effective factors and methods of dormancy elimination was reviewed in a practical way.
Meysam Miri, Mohammdreza Amerian, Mohsen Edalat, Mehdi Baradaran Firouzabadi, Hasan Makarian,
Volume 8, Issue 2 (3-2022)
Volume 8, Issue 2 (3-2022)
Abstract
Extended Abstract
Introduction: Germination is considered the first and most important stage of establishment and consequently, successful competition which is influenced by genetic and environmental factors. Among the environmental factors influencing the germination, temperature and light are the most important ones. Using different models, the germination response of seeds to temperature can be quantified; therefore, this study was performed to investigate the effect of temperature on germination and to quantify the germination response of Buckwheat seed (Fagopyrum esculentum Moenc) to temperature using nonlinear regression models and thermal-time model.
Materials and methods: The seeds were germinated in 4 replications of 25 seeds under 8 constant temperature treatments (5, 10, 15, 20, 25, 30, 35 and 40 ° C). Using a three-parameter logistic model, Buckwheat seed germination was quantified at different temperature levels and the percentage and time to reach 50% germination were obtained. Four nonlinear regression models and a thermal-time model were used to quantify the response of Buckwheat seed germination rate to temperature. To compare the models and determine the most appropriate model, the root mean square error index (RMSE), coefficient of determination (R2), coefficient of variation (CV) and standard error (SE) were used for the observed germination rate versus the predicted germination rate.
Results: The results indicated that temperature affected the seedling length, normal seedling percentage, seed vigor and the germination rate as well as germination percentage. Also, the results showed that germination characteristics increased with increasing temperature up to 20 and 25 °C. Comparison of the three models based on the root mean square error (RMSE) of germination time, the coefficient of determination (R2), CV and SE, the best model to determine the cardinal temperatures of Fagopyrum esculentum was the dent-like model. The results of thermal-time model showed that the base temperature of Fagopyrum esculentum seeds was 4.01 ° C and the thermal-time coefficient was 1242.6 h° C.
Conclusion: Utilization of non-linear regression models (segmented, dent-like and beta) and thermal-time model to quantify the germination response of Fagopyrum esculentum response to different temperatures led to acceptable results. Therefore, germination rate and percentage may be predicted using the outputs of these models at different temperatures.
Highlights:
Introduction: Germination is considered the first and most important stage of establishment and consequently, successful competition which is influenced by genetic and environmental factors. Among the environmental factors influencing the germination, temperature and light are the most important ones. Using different models, the germination response of seeds to temperature can be quantified; therefore, this study was performed to investigate the effect of temperature on germination and to quantify the germination response of Buckwheat seed (Fagopyrum esculentum Moenc) to temperature using nonlinear regression models and thermal-time model.
Materials and methods: The seeds were germinated in 4 replications of 25 seeds under 8 constant temperature treatments (5, 10, 15, 20, 25, 30, 35 and 40 ° C). Using a three-parameter logistic model, Buckwheat seed germination was quantified at different temperature levels and the percentage and time to reach 50% germination were obtained. Four nonlinear regression models and a thermal-time model were used to quantify the response of Buckwheat seed germination rate to temperature. To compare the models and determine the most appropriate model, the root mean square error index (RMSE), coefficient of determination (R2), coefficient of variation (CV) and standard error (SE) were used for the observed germination rate versus the predicted germination rate.
Results: The results indicated that temperature affected the seedling length, normal seedling percentage, seed vigor and the germination rate as well as germination percentage. Also, the results showed that germination characteristics increased with increasing temperature up to 20 and 25 °C. Comparison of the three models based on the root mean square error (RMSE) of germination time, the coefficient of determination (R2), CV and SE, the best model to determine the cardinal temperatures of Fagopyrum esculentum was the dent-like model. The results of thermal-time model showed that the base temperature of Fagopyrum esculentum seeds was 4.01 ° C and the thermal-time coefficient was 1242.6 h° C.
Conclusion: Utilization of non-linear regression models (segmented, dent-like and beta) and thermal-time model to quantify the germination response of Fagopyrum esculentum response to different temperatures led to acceptable results. Therefore, germination rate and percentage may be predicted using the outputs of these models at different temperatures.
Highlights:
- The best temperature for Fagopyrum esculentum Moenc. seed germination is 20-25 Celsius.
- The dent-like model was determined the most appropriate model for estimating the cardinal temperatures of Buckwheat.
Majed Chaab, Mohammad Ali Ebrahimi, Sara Ghezelbash, Nasim Zarinpanjeh,
Volume 8, Issue 2 (3-2022)
Volume 8, Issue 2 (3-2022)
Abstract
Extended Abstract
Introduction: Cow tail (Smirnovia iranica) is considered a valuable shrub species indigenous and adapted to the sandy lands of the Iranian central regions which besides playing an essential role in the desert cover for soil protection and of forage production, is considered important due to its great medicinal values. Considering the fact that seed germination of this plant does not easily occur due to its hard and solid seed coat, in this study, the in vitro tissue culture and seedling establishment is utilized for the first time in order to surmount the obstacles laid ahead of cow tail seed germination.
Materials and Methods: Scratched seed, unscratched seed and seed embryo of cow tail as different explants were placed in two culture media (MS, MS with free amino acids complex) following surface sterilization, and were exposed to two photoperiod treatments (16 hours of light and 8 hours of darkness as well as absolute darkness) and were investigated in a factorial experiment based on completely randomized design with six replications. Finally, germination percentage (10 days after seed culturing) and shoot length (30 days after seed germination) were evaluated.
Results: The results indicated that significance of the effect of investigated treatment conducted over some in vitro on germination characteristics. It was revealed that the cultivation of seed embryo in MS culture media along with free amino acids complex for 16 hours of light and 8 hours of darkness photo period can be considered as the best in vitro germination method, in terms of seed germination percentage (78.83%) and germinated shoot length (44.83 mm).
Conclusion: In vitro culture can be used to improve germination and seeding production of this species.
Highlights:
- The method for seed dormancy elimination of cow tail plant was introduced.
- The seed disinfection procedure for in vitro culture of cow tail plant was introduced.
- The components of in vitro culture medium for rapid and efficient seed germination of cow tail plant were introduced.
Mohaddese Heydarzade, Seyed Mohammadreza Ehteshami, Mohammad Rabiee,
Volume 9, Issue 1 (9-2022)
Volume 9, Issue 1 (9-2022)
Abstract
Extended Abstract
Introduction: Guar (Cyamopsis tetragonoloba L.) is an annual, dicotyledonous plant of the legume family, also known as cluster beans. This plant can tolerate salinity and drought stress well. Optimal planting date and plant density are factors affecting the quality and quantity of crops. The distribution of plants in the field influences the absorption and productivity of environmental factors affecting the growth and intra- and inter- competition and eventually is one of the factors determining the quantity and quality of yield. Different planting dates set off different conditions in terms of temperature day length, relative humidity, solar radiation, ripening and harvest time and thus, affect the quantitative and qualitative characteristics of seeds. The purpose of this experiment is to evaluate the quality and also to evaluate some of the germination characteristics of Guar seeds at different dates and planting densities under the climatic conditions of Guilan.
Materials and Methods: This experiment was conducted in the spring and summer of 2017 in the research farm of Rasht Rice Research Institute located in Gil Pardehsar village at Sangar as a factorial based on a randomized complete block design with three replications. Experimental treatments included four planting dates (12 May, 26 May, 9 June and 23 June) and three plant densities (20, 40 and 60 plants. m-2). Seed harvesting was done as the pods in 75% of the plants in each plot turned brown and traits such as germination percentage, germination rate, root and shoot length and fresh and dry weight of roots and shoots, longitudinal index of seedling vigor, 1000- grain weight, electrical conductivity and alpha-amylase activity were investigated.
Results: The results of the present study showed that guar seeds had the highest quality on 26 May and a density of 40 plants.m-2. Due to favorable climatic conditions during the period of seed filling, germination rate, germination percentage, seedling vigor index, root length and 1000- grain weight was high on 26 May. The amount of these traits decreased with delay in planting. The amount of electrical conductivity in 23 June date of planting treatment showed the highest value. The highest level of alpha-amylase activity was observed on 9 June.
Conclusions: In general, it can be concluded that the best planting date and plant density of guar seeds in Guilan province with the highest quality of seeds and germination is on 26 May and 40 plants.m-2.
Highlights:
1- Guar seed germination traits were evaluated at physiological maturity.
2- In terms of germination traits of guar seeds, the best planting date was 26 May and the best plant density was obtained at 40 per square meter
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