University of Guilan Cereal Research 2252-0163 15 4 2025 12 22 Evaluation of factors affecting rice prices in the world Evaluation of factors affecting rice prices in the world 331 349 9166 10.22124/cr.2025.31019.1869 FA Maryam Hosseini Chaleshtori Research Associate Professor, Agricultural Research, Education and Extension Organization (AREEO), Rice Research Institute of Iran, Rasht, Iran Afsaneh Berenjkar Gorabi Ph.D. Graduate, Agricultural Research, Education and Extension Organization (AREEO), Rice Research Institute of Iran, Rasht, Iran Journal Article 2025 07 29 Introduction: Rice is a valuable food commodity in the world, most of which is produced and consumed in Asian countries, plays an important role in providing the required calories compared to other foods especially for Asian people. This valuable cereal grain has experienced significant price fluctuations over the past years due to various factors, which has limited its availability to consumers, especially in poor countries. The aim of this review-analytical study was to assess the factors affecting the fluctuations in rice prices in the world in different periods from 1970 to 2025, and to study the trend of rice prices changes in the years when rice experienced the highest prices in the world. Materials and Methods: In this review-analytical study, fluctuations in rice prices in the world from 1990 to 2025 and their various reasons have been examined and analyzed based on reliable scientific references. Results and Discussion: The results of this study showed that the highest rice prices were recorded during the crisis years of 2008, 2013, 2021, 2023 and 2024, the reasons of which can be considered a result of a combination of natural factors and social activities. On the one hand, climate hazards such as successive droughts (in 2006 and 2007), destructive storms (in 2007, and hurricane narcissus in 2013), abnormal cold (in 2008), and the El Niño phenomenon (in 2023 and 2024) were directly associated with a decrease in rice yields and supplies in key producing countries. On the other hand, several human and economic factors also played a role in exacerbating this crisis, including the increase in the prices of vital inputs such as oil, fertilizers and pesticides at critical times (2008 and 2021), geopolitical tensions such as the Russia-Ukraine war, and disruptions caused by the Covid-19 pandemic in the global supply chain. Meanwhile, the political reaction of some major producers, especially the imposition of export restrictions by India, the world’s largest rice exporter, as an aggravating factor, had a direct impact on the global market. The gradual impact of long-term structural factors such as the shift in consumption patterns towards protein has also added to the complexity of the demand equation. The results of these multiple drivers led to a reduction in global reserves, supply constraints, and ultimately an increase in rice prices during these specific periods. Among these years, 2008 was the price crisis point for cereals, especially rice. Although rice prices have also increased after that, 2008 can be considered as the critical point of rice prices, which has experienced a price jump. Conclusion: Rice price have greatly fluctuated since 1970 and it’s trend have been upward. Drought, storms, floods, the Russia-Ukraine war, COVID-19, export bans, rising fuel prices, the dollar’s depreciation against the euro, and changes in the diets of developing countries can be introduced as the most important factors affecting the increase in rice prices. Therefore, rice-importing countries, including Iran, should have appropriate and comprehensive planning to increase local rice production and reduce imports on the agenda. Introduction: Rice is a valuable food commodity in the world, most of which is produced and consumed in Asian countries, plays an important role in providing the required calories compared to other foods especially for Asian people. This valuable cereal grain has experienced significant price fluctuations over the past years due to various factors, which has limited its availability to consumers, especially in poor countries. The aim of this review-analytical study was to assess the factors affecting the fluctuations in rice prices in the world in different periods from 1970 to 2025, and to study the trend of rice prices changes in the years when rice experienced the highest prices in the world. Materials and Methods: In this review-analytical study, fluctuations in rice prices in the world from 1990 to 2025 and their various reasons have been examined and analyzed based on reliable scientific references. Results and Discussion: The results of this study showed that the highest rice prices were recorded during the crisis years of 2008, 2013, 2021, 2023 and 2024, the reasons of which can be considered a result of a combination of natural factors and social activities. On the one hand, climate hazards such as successive droughts (in 2006 and 2007), destructive storms (in 2007, and hurricane narcissus in 2013), abnormal cold (in 2008), and the El Niño phenomenon (in 2023 and 2024) were directly associated with a decrease in rice yields and supplies in key producing countries. On the other hand, several human and economic factors also played a role in exacerbating this crisis, including the increase in the prices of vital inputs such as oil, fertilizers and pesticides at critical times (2008 and 2021), geopolitical tensions such as the Russia-Ukraine war, and disruptions caused by the Covid-19 pandemic in the global supply chain. Meanwhile, the political reaction of some major producers, especially the imposition of export restrictions by India, the world’s largest rice exporter, as an aggravating factor, had a direct impact on the global market. The gradual impact of long-term structural factors such as the shift in consumption patterns towards protein has also added to the complexity of the demand equation. The results of these multiple drivers led to a reduction in global reserves, supply constraints, and ultimately an increase in rice prices during these specific periods. Among these years, 2008 was the price crisis point for cereals, especially rice. Although rice prices have also increased after that, 2008 can be considered as the critical point of rice prices, which has experienced a price jump. Conclusion: Rice price have greatly fluctuated since 1970 and it’s trend have been upward. Drought, storms, floods, the Russia-Ukraine war, COVID-19, export bans, rising fuel prices, the dollar’s depreciation against the euro, and changes in the diets of developing countries can be introduced as the most important factors affecting the increase in rice prices. Therefore, rice-importing countries, including Iran, should have appropriate and comprehensive planning to increase local rice production and reduce imports on the agenda.

https://cr.guilan.ac.ir/article_9166_01db4d29cdc70397f8327727526b4519.pdf

University of Guilan Cereal Research 2252-0163 15 4 2025 12 22 Responses of morphological, phenological and yield traits of wheat cultivars and early maturing near-isogenic lines to irrigation cut-off at reproductive growth stages Responses of morphological, phenological and yield traits of wheat cultivars and early maturing near-isogenic lines to irrigation cut-off at reproductive growth stages 351 367 9266 10.22124/cr.2025.31509.1878 FA Mozhdeh Jalilifar Ph.D. Student, Department of Plant Production and Genetics, Faculty of Agriculture, Shahid Chamran University of Ahvaz, Ahvaz, Iran Afrasyab Rahnama Professor, Department of Plant Production and Genetics, Faculty of Agriculture, Shahid Chamran University of Ahvaz, Ahvaz, Iran Roohollah Abdolshahi Associate Professor, Department of Plant Production and Genetics, Shahid Bahonar University of Kerman, Kerman, Iran Journal Article 2025 08 26 Introduction: In arid and semi-arid regions, drought stress particularly during the reproductive and late-season stages, often accompanied by high temperatures substantially reduces wheat yield. The use of early-maturing cultivars with shortened growth cycles, which complete development prior to the onset of stress, represents an effective strategy to mitigate these adverse effects. This study aimed to investigate the effects of drought stress on morphological, phenological, and functional traits of early-maturing near-isogenic wheat lines subjected to irrigation cutt-off during reproductive growth. Materials and Methods: The experiment was carried out in split-plot based on a randomized complete block design with three replications at the research field of Shahid Chamran University of Ahvaz, Ahvaz, Khuzestan province, Iran, in 2024-2025 growing season. Irrigation treatments at three levels, including full irrigation (control), irrigation cut-off from the beginning of flowering to early dough stage (code 61-83 in BBCH scale) and irrigation cut-off from early dough stage to full grain maturity (code 83-92 in BBCH scale) was considered as main factor, and five bread wheat cultivars and near-isogenic lines as sub-factor. The measured traits included phenological and morphological traits, yield components, biological yield and harvest index. To group the studied genotypes and traits, cluster analysis method was used and the respective dendrogram was drawn as a heat map using R-studio ver. 2023 software. Data analysis of variance was conducted using SAS ver. 9.1 software and comparison of means was performed using Duncan’s multiple range test. Results and Discussion: The results of this study indicated that irrigation cut-off at different growth stages significantly reduced the number and weight of grains per spike, 1000-grain weight, and days to maturity, ultimately leading to decreased grain yield across all cultivars and near-isogenic lines. However, greater reductions were obsberved in the cultivars compared with their corresponding near-isogenic lines. Under irrigation cut-off applied at the flowering stage, the grain yield of Roshan and it’s near-isogenic line, Mahdavi and it’s near-isogenic line, and Mehregan decreased by 33%, 38%, 29%, 29% and 20%, respectively, and under irrigation cut-off at the grain-filling stage decreased by 12%, 15%, 15%, 15% and 8%, respectively, compared with full irrigation treatment. Across all irrigation cut-off treatments, the number of days from seed sowing to maturity in near-isogenic lines of Roshan and Mahdavi was 10 to 15 days fewer than their parental cultivars. This earliness likely contributed to reduced exposure to drought stress during critical reproductive stages, enhancing yield stability. Conclusion: Overall, the findings of this study showed that the the near-isogenic lines outperformed their parent cultivars in terms of yield and other agronomic traits. The near-isogenic line of Mahdavi, by employing an earliness strategy and shortening the time to flowering and maturity, achieved the highest grain yield under both full irrigation and cut-off irrigation treatments. Therefore, similar to the Mehregan cultivar, it is recommended for cultivation under mild water stress conditions in the Khuzestan region. Introduction: In arid and semi-arid regions, drought stress particularly during the reproductive and late-season stages, often accompanied by high temperatures substantially reduces wheat yield. The use of early-maturing cultivars with shortened growth cycles, which complete development prior to the onset of stress, represents an effective strategy to mitigate these adverse effects. This study aimed to investigate the effects of drought stress on morphological, phenological, and functional traits of early-maturing near-isogenic wheat lines subjected to irrigation cutt-off during reproductive growth. Materials and Methods: The experiment was carried out in split-plot based on a randomized complete block design with three replications at the research field of Shahid Chamran University of Ahvaz, Ahvaz, Khuzestan province, Iran, in 2024-2025 growing season. Irrigation treatments at three levels, including full irrigation (control), irrigation cut-off from the beginning of flowering to early dough stage (code 61-83 in BBCH scale) and irrigation cut-off from early dough stage to full grain maturity (code 83-92 in BBCH scale) was considered as main factor, and five bread wheat cultivars and near-isogenic lines as sub-factor. The measured traits included phenological and morphological traits, yield components, biological yield and harvest index. To group the studied genotypes and traits, cluster analysis method was used and the respective dendrogram was drawn as a heat map using R-studio ver. 2023 software. Data analysis of variance was conducted using SAS ver. 9.1 software and comparison of means was performed using Duncan’s multiple range test. Results and Discussion: The results of this study indicated that irrigation cut-off at different growth stages significantly reduced the number and weight of grains per spike, 1000-grain weight, and days to maturity, ultimately leading to decreased grain yield across all cultivars and near-isogenic lines. However, greater reductions were obsberved in the cultivars compared with their corresponding near-isogenic lines. Under irrigation cut-off applied at the flowering stage, the grain yield of Roshan and it’s near-isogenic line, Mahdavi and it’s near-isogenic line, and Mehregan decreased by 33%, 38%, 29%, 29% and 20%, respectively, and under irrigation cut-off at the grain-filling stage decreased by 12%, 15%, 15%, 15% and 8%, respectively, compared with full irrigation treatment. Across all irrigation cut-off treatments, the number of days from seed sowing to maturity in near-isogenic lines of Roshan and Mahdavi was 10 to 15 days fewer than their parental cultivars. This earliness likely contributed to reduced exposure to drought stress during critical reproductive stages, enhancing yield stability. Conclusion: Overall, the findings of this study showed that the the near-isogenic lines outperformed their parent cultivars in terms of yield and other agronomic traits. The near-isogenic line of Mahdavi, by employing an earliness strategy and shortening the time to flowering and maturity, achieved the highest grain yield under both full irrigation and cut-off irrigation treatments. Therefore, similar to the Mehregan cultivar, it is recommended for cultivation under mild water stress conditions in the Khuzestan region.

https://cr.guilan.ac.ir/article_9266_6d348c17f7673220895b5fa6af41fd8b.pdf

University of Guilan Cereal Research 2252-0163 15 4 2025 12 22 Investigating the yield gap and it's influencing factors in irrigated wheat fields of Azna county, Lorestan province, Iran, using comparative performance analysis (CPA) Investigating the yield gap and it's influencing factors in irrigated wheat fields of Azna county, Lorestan province, Iran, using comparative performance analysis (CPA) 369 381 9427 10.22124/cr.2026.31499.1877 FA Hossein Pourhadian Assistant Professor, Department of Agriculture, Payame Noor University, Tehran, Iran 0000-0002-3422-3742 Journal Article 2025 08 25 Introduction: Wheat is one of the most important plant affecting human life due to various application. Diverse management practices of farmers is caused the potential of the agricultural lands are often not optimally utilized, resulting in low yields per unit area. The comparative performance analysis (CPA) method effectively estimates yield differences based on the potential of the land and the yield resulting from farmer’s management. This study was planned and implemented to investigate the yield gap and its contributing factors in the irrigated wheat fields of Azna county, Lorestan province, Iran, using the CPA method. Materials and Methods: In this study, data from 74 irrigated wheat farms in Azna county were used to estimate the yield gap and its contributing factors through the CPA method. The data from the wheat fields were collected using a questionnaire including farm characteristics, planting, maintenance, and harvesting operations. Topographic and soil information for each wheat field were also obtained from the GIS-prepared layers based on their geographical locations. To determine the yield model (output), the relationship between all measured variables and yield was examined using stepwise regression analysis with SAS software. Finally, using the derived production equation, the yield gap and its contributing factors, along with the share of each, were identified. Results and Discussion: The results of this study showed that the minimum and maximum observed yield of wheat fields were 2500 and 8500 kg.ha-1, respectively, with the average of 5943 kg.ha-1. Also, the average, minimum and maximum yield estimated by the model were 5906.62, 3248.22 and 11289.24 kg.ha-1, respectively, and the total yield gap was 5382.62 kg.ha-1. The correlation coefficient between the estimated yield and the actual yield of farmers was 0.81, and the residual root mean square (RMSE) and the coefficient of variation (CV) of the model were obtained 842.71 kg.ha-1 and 14.27%, respectively. The analysis of the factors contributing to the yield gap indicated the role of six variables, including low organic matter in the soil (26.8%), lack of row planting (3.60%), low seed usage (10.96%), reduced number of irrigations in the fall (18.88%), reduced amounts of nitrogen applied as top-dressing fertilizer (17.28%), and untimely harvesting (22.43%), in creating the yield gap in irrigated wheat fields in Azna county. Conclusion: This study confirms the acceptable capability of the CPA method in estimating the yield gap and the factors affecting it in the wheat fields of Azna county. The results showed that with timely, targeted, and intelligent management, the yield gap can be reduced by approximately 48%. Implementing appropriate crop rotation, managing wheat and other crop residues, use of animal manure, promoting the use of row planters and providing them to farmers, managing seedbed preparation, selecting suitable varieties, and strongly recommending fall irrigation, soil testing to determine appropriate nitrogen fertilizer levels, and distributing it according to the growth stages of wheat, along with precise planning to avoid overlap in spring crop cultivation with wheat harvesting and timely entry of harvesting machinery into wheat fields are recommended to reduce the yield gap based on the influencing factors. Introduction: Wheat is one of the most important plant affecting human life due to various application. Diverse management practices of farmers is caused the potential of the agricultural lands are often not optimally utilized, resulting in low yields per unit area. The comparative performance analysis (CPA) method effectively estimates yield differences based on the potential of the land and the yield resulting from farmer’s management. This study was planned and implemented to investigate the yield gap and its contributing factors in the irrigated wheat fields of Azna county, Lorestan province, Iran, using the CPA method. Materials and Methods: In this study, data from 74 irrigated wheat farms in Azna county were used to estimate the yield gap and its contributing factors through the CPA method. The data from the wheat fields were collected using a questionnaire including farm characteristics, planting, maintenance, and harvesting operations. Topographic and soil information for each wheat field were also obtained from the GIS-prepared layers based on their geographical locations. To determine the yield model (output), the relationship between all measured variables and yield was examined using stepwise regression analysis with SAS software. Finally, using the derived production equation, the yield gap and its contributing factors, along with the share of each, were identified. Results and Discussion: The results of this study showed that the minimum and maximum observed yield of wheat fields were 2500 and 8500 kg.ha-1, respectively, with the average of 5943 kg.ha-1. Also, the average, minimum and maximum yield estimated by the model were 5906.62, 3248.22 and 11289.24 kg.ha-1, respectively, and the total yield gap was 5382.62 kg.ha-1. The correlation coefficient between the estimated yield and the actual yield of farmers was 0.81, and the residual root mean square (RMSE) and the coefficient of variation (CV) of the model were obtained 842.71 kg.ha-1 and 14.27%, respectively. The analysis of the factors contributing to the yield gap indicated the role of six variables, including low organic matter in the soil (26.8%), lack of row planting (3.60%), low seed usage (10.96%), reduced number of irrigations in the fall (18.88%), reduced amounts of nitrogen applied as top-dressing fertilizer (17.28%), and untimely harvesting (22.43%), in creating the yield gap in irrigated wheat fields in Azna county. Conclusion: This study confirms the acceptable capability of the CPA method in estimating the yield gap and the factors affecting it in the wheat fields of Azna county. The results showed that with timely, targeted, and intelligent management, the yield gap can be reduced by approximately 48%. Implementing appropriate crop rotation, managing wheat and other crop residues, use of animal manure, promoting the use of row planters and providing them to farmers, managing seedbed preparation, selecting suitable varieties, and strongly recommending fall irrigation, soil testing to determine appropriate nitrogen fertilizer levels, and distributing it according to the growth stages of wheat, along with precise planning to avoid overlap in spring crop cultivation with wheat harvesting and timely entry of harvesting machinery into wheat fields are recommended to reduce the yield gap based on the influencing factors.

https://cr.guilan.ac.ir/article_9427_ee01f9152029d37b90ac5d11d12a525f.pdf

University of Guilan Cereal Research 2252-0163 15 4 2025 12 22 Response of grain millet hybrids to environmental diversity and identification of high-yielding stable hybrids Response of grain millet hybrids to environmental diversity and identification of high-yielding stable hybrids 383 394 9265 10.22124/cr.2025.30599.1865 FA Reza Ataei Research Assistant Professor, Seed and Plant Improvement Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran Ahmad Ghasemi Research Assistant Professor, Sistan Agriculture and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Zabol, Iran Ali Azari-Nasrabad Research Assistant Professor, South Khorasan Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Birjand, Iran Masoud Torabi Research Associate Professor, Isfahan Agriculture and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Isfahan, Iran Mohammadreza Shiri Research Associate Professor, Seed and Plant Improvement Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran Journal Article 2025 08 07 Introduction: Pearl millet (Pennisetum glaucum L.) is one of the most important crops in warm and arid regions, playing a key role in food security across arid and semi-arid areas of the world. Due to climate change and increasing environmental fluctuations, the need to develop high-yielding and stable hybrids has become more crucial than ever. Given the nature of cross-pollination and high heterosis potential, the development of hybrid cultivars is the main breeding strategy in pearl millet. Hybrid varieties of pearl millet can significantly enhance both yield and stability under diverse agro-climatic conditions. However, it is necessary to assess genotype × environment interaction (GEI) for selecting superior hybrids in different climatic regions. The objective of this study was to evaluate the stability of promising pearl millet hybrids and to identify stable, high-yielding, and well-adapted hybrids for the target regions. Materials and Methods: The plant materials consisted of eleven promising pearl millet hybrids along with the check cultivar ‘Mehran’. The experiment was conducted in a randomized complete block design (RCBD) with three replications across eight environments (four locations, Karaj, Birjand, Isfahan and Zabol, during two cropping seasons, 2022 and 2023). The traits evaluated included days to 50% flowering, plant height, panicle length, panicle diameter, number of tillers, 1000-grain weight, and grain yield. Statistical analyses were performed using SAS software, and mean comparisons were conducted using Duncan’s multiple range test. Stability analysis was also performed using the Lin and Binns, rank-based stability parameters, and GGE-Biplot methods to identify stable and high-yielding hybrids. Results and Discussion: Combined analysis of variance and comparison of means revealed significant genetic variability among the pearl millet hybrids for all studied traits. The effects of environment and GEI were also significant on all measured traits including grain yield. The results indicated that the studied genotypes exhibited both crossover and non-crossover types of interactions. Comparison of means showed that two hybrids H794 and H824 with 8.41 and 7.81 t.ha-1, respectively, produced the highest grain yield. The results of the stability analysis using rank-based, superiority index, and GGE-Biplot methods showed that two promising hybrids H794 and H824 had the higher grain yield and stability across all studied environments. Conclusion: This study clearly demonstrated the potential of exploiting heterosis in pearl millet to produce high-yielding hybrid varieties. The results indicated that all evaluated hybrids outperformed the check cultivar ‘Mehran’. Introducing these promising hybrids could significantly enhance the national average grain yield of pearl millet. Moreover, considering the ongoing water scarcity crisis in the country, the dissemination of high-yielding and drought-efficient hybrids could encourage farmers to cultivate this low-water-requirement crop. Introduction: Pearl millet (Pennisetum glaucum L.) is one of the most important crops in warm and arid regions, playing a key role in food security across arid and semi-arid areas of the world. Due to climate change and increasing environmental fluctuations, the need to develop high-yielding and stable hybrids has become more crucial than ever. Given the nature of cross-pollination and high heterosis potential, the development of hybrid cultivars is the main breeding strategy in pearl millet. Hybrid varieties of pearl millet can significantly enhance both yield and stability under diverse agro-climatic conditions. However, it is necessary to assess genotype × environment interaction (GEI) for selecting superior hybrids in different climatic regions. The objective of this study was to evaluate the stability of promising pearl millet hybrids and to identify stable, high-yielding, and well-adapted hybrids for the target regions. Materials and Methods: The plant materials consisted of eleven promising pearl millet hybrids along with the check cultivar ‘Mehran’. The experiment was conducted in a randomized complete block design (RCBD) with three replications across eight environments (four locations, Karaj, Birjand, Isfahan and Zabol, during two cropping seasons, 2022 and 2023). The traits evaluated included days to 50% flowering, plant height, panicle length, panicle diameter, number of tillers, 1000-grain weight, and grain yield. Statistical analyses were performed using SAS software, and mean comparisons were conducted using Duncan’s multiple range test. Stability analysis was also performed using the Lin and Binns, rank-based stability parameters, and GGE-Biplot methods to identify stable and high-yielding hybrids. Results and Discussion: Combined analysis of variance and comparison of means revealed significant genetic variability among the pearl millet hybrids for all studied traits. The effects of environment and GEI were also significant on all measured traits including grain yield. The results indicated that the studied genotypes exhibited both crossover and non-crossover types of interactions. Comparison of means showed that two hybrids H794 and H824 with 8.41 and 7.81 t.ha-1, respectively, produced the highest grain yield. The results of the stability analysis using rank-based, superiority index, and GGE-Biplot methods showed that two promising hybrids H794 and H824 had the higher grain yield and stability across all studied environments. Conclusion: This study clearly demonstrated the potential of exploiting heterosis in pearl millet to produce high-yielding hybrid varieties. The results indicated that all evaluated hybrids outperformed the check cultivar ‘Mehran’. Introducing these promising hybrids could significantly enhance the national average grain yield of pearl millet. Moreover, considering the ongoing water scarcity crisis in the country, the dissemination of high-yielding and drought-efficient hybrids could encourage farmers to cultivate this low-water-requirement crop.

https://cr.guilan.ac.ir/article_9265_63583ac9f26a411db2e92312267e1619.pdf

University of Guilan Cereal Research 2252-0163 15 4 2025 12 22 Physiological and molecular mechanisms of salinity tolerance in cereals: I. Fundamentals and methods Physiological and molecular mechanisms of salinity tolerance in cereals: I. Fundamentals and methods 395 414 9439 10.22124/cr.2025.31687.1880 FA Ahmad Majidimehr Research Assistant Professor, National Salinity Research Center, Agricultural Research, Education and Extension Organization (AREEO), Yazd, Iran. Reza Amiri-Fahliani Associate Professor, Department of Agronomy and Plant Breeding, Faculty of Agriculture, Yasouj University, Yasouj, Iran. Bahram Heidari Professor, Department of Plant Production and Genetics, Faculty of Agriculture, Shiraz University, Shiraz, Iran Gholamhassan Ranjbar Research Associate Professor, National Salinity Research Center, Agricultural Research, Education and Extension Organization (AREEO), Yazd, Iran 0000-0003-4314-9772 Journal Article 2025 09 15 Introduction: Cereals, as the main components of the human diet, play a decisive role in ensuring the food security of the world’s population. The production of these crops particularly in arid and semi-arid regions faces numerous challenges, with abiotic stresses such as drought, salinity, heat, and cold capable of significantly reducing their yields. Among these factors, salinity stress is recognized as a major constraint on crop production. The key question is: how are cereals able to perceive environmental cues and activate their defense pathways through intricate regulatory networks to cope with such stress? The aim of the present study is to provide a comprehensive overview in understanding the physiological and molecular mechanisms of salt tolerance in crop plants, with a special focus on cereals. Materials and Methods: This review study, with an innovative and dual approach, covers recent advances in salinity tolerance mechanisms, especially in cereals. The main innovation of this study compared to similar studies is in providing an integrated and step-by-step analytical framework on the physiological and molecular basis of salinity tolerance mechanisms citing the most recent findings. RResults and Discussion: Salinity stress in most plants typically occurs in two distinct phases, first osmotic stress, followed by ionic toxicity, leading to secondary stresses such as oxidative stress and nutritional imbalances. From a physiological perspective, plants cope with salinity stress by employing effective systems that regulate ion uptake and distribution, maintain osmotic balance, and accumulate protective compounds. At the biochemical level, the activation of antioxidant systems and the production of compatible solutes such as proline are key strategies for mitigating the oxidative stress induced by salinity. At the molecular level, complex networks of transcription factors and functional genes including NHX1, HKT1, SOS, and P5CS are responsible for coordinating the stress response. Key signaling pathways, such as the MAPK cascade and the SOS pathway, play a central role in transducing stress signals and activating defense responses. The molecular processes salt tolerance are coordinated through extensive regulatory networks comprising transcription factors and functional genes. The MAPK and SOS pathways have been extensively studied in cereals, and our understanding of salt tolerance is grounded in research specifically focused on these plants. For instance, the SOS1, SOS2, and SOS3 genes in rice enhance salt tolerance by facilitating sodium ion efflux from cells and preventing ionic toxicity. Furthermore, the accumulation of osmolytic compounds (including proline) and the activation of antioxidant systems play a crucial role in maintaining cellular integrity in plants under salinity stress. Conclusion: Given the polygenic and complex nature of salt tolerance, integrating physiological, genetic, and molecular mechanisms into breeding programs, along with leveraging genomic approaches, appears essential for developing new salt-tolerant and stable-yielding cereal varieties. Introduction: Cereals, as the main components of the human diet, play a decisive role in ensuring the food security of the world’s population. The production of these crops particularly in arid and semi-arid regions faces numerous challenges, with abiotic stresses such as drought, salinity, heat, and cold capable of significantly reducing their yields. Among these factors, salinity stress is recognized as a major constraint on crop production. The key question is: how are cereals able to perceive environmental cues and activate their defense pathways through intricate regulatory networks to cope with such stress? The aim of the present study is to provide a comprehensive overview in understanding the physiological and molecular mechanisms of salt tolerance in crop plants, with a special focus on cereals. Materials and Methods: This review study, with an innovative and dual approach, covers recent advances in salinity tolerance mechanisms, especially in cereals. The main innovation of this study compared to similar studies is in providing an integrated and step-by-step analytical framework on the physiological and molecular basis of salinity tolerance mechanisms citing the most recent findings. RResults and Discussion: Salinity stress in most plants typically occurs in two distinct phases, first osmotic stress, followed by ionic toxicity, leading to secondary stresses such as oxidative stress and nutritional imbalances. From a physiological perspective, plants cope with salinity stress by employing effective systems that regulate ion uptake and distribution, maintain osmotic balance, and accumulate protective compounds. At the biochemical level, the activation of antioxidant systems and the production of compatible solutes such as proline are key strategies for mitigating the oxidative stress induced by salinity. At the molecular level, complex networks of transcription factors and functional genes including NHX1, HKT1, SOS, and P5CS are responsible for coordinating the stress response. Key signaling pathways, such as the MAPK cascade and the SOS pathway, play a central role in transducing stress signals and activating defense responses. The molecular processes salt tolerance are coordinated through extensive regulatory networks comprising transcription factors and functional genes. The MAPK and SOS pathways have been extensively studied in cereals, and our understanding of salt tolerance is grounded in research specifically focused on these plants. For instance, the SOS1, SOS2, and SOS3 genes in rice enhance salt tolerance by facilitating sodium ion efflux from cells and preventing ionic toxicity. Furthermore, the accumulation of osmolytic compounds (including proline) and the activation of antioxidant systems play a crucial role in maintaining cellular integrity in plants under salinity stress. Conclusion: Given the polygenic and complex nature of salt tolerance, integrating physiological, genetic, and molecular mechanisms into breeding programs, along with leveraging genomic approaches, appears essential for developing new salt-tolerant and stable-yielding cereal varieties.

https://cr.guilan.ac.ir/article_9439_d6fa541ae3e48d5b369bf8687be42b87.pdf

University of Guilan Cereal Research 2252-0163 15 4 2025 12 22 Physiological and molecular mechanisms of salinity tolerance in cereals: II. Advanced breeding methods and future perspectives Physiological and molecular mechanisms of salinity tolerance in cereals: II. Advanced breeding methods and future perspectives 415 433 9464 10.22124/cr.2026.32537.1886 FA Ahmad Majidimehr Research Assistant Professor, National Salinity Research Center, Agricultural Research, Education and Extension Organization (AREEO), Yazd, Iran. Reza Amiri-Fahliani Associate Professor, Department of Agronomy and Plant Breeding, Faculty of Agriculture, Yasouj University, Yasouj, Iran Bahram Heidari Professor, Department of Plant Production and Genetics, Faculty of Agriculture, Shiraz University, Shiraz, Iran Gholamhassan Ranjbar Research Associate Professor, National Salinity Research Center, Agricultural Research, Education and Extension Organization (AREEO), Yazd, Iran 0000-0003-4314-9772 Journal Article 2025 10 18 Introduction: Salinity, as one of the most significant limiting factors for the growth and production of strategic crops such as wheat, rice, and maize, poses a serious threat to global food security. Given the high cost and time-consuming nature of physical remediation of saline soils, developing tolerant varieties through breeding programs is the most effective and economical approach to addressing this challenge. In this regard, understanding the molecular and genetic mechanisms of salt tolerance is essential for generating new, salt-tolerant genotypes. The aim of the present study was to review recent advances and investigate the application of modern breeding technologies to accelerate the development of salt-tolerant varieties in crop plants, particularly cereals. Materials and Methods: This review study systematically describes the application of novel biotechnologies including the integration of omics tools, genomic mapping, marker-assisted selection (MAS), and genome editing to efficiently transfer identified genes and QTLs into elite genotypes and to expedite breeding programs. Results and Discussion: Marker-assisted selection is an efficient breeding method that, instead of relying solely on phenotype, enables the selection of superior genotypes using DNA banding patterns at early stages of organism development. By reducing environmental influence, this approach enhances the accuracy and speed of breeding programs and significantly shortens the breeding cycle, which in classical methods may take approximately eight to ten years. The successful application of MAS has been demonstrated in transferring QTLs such as Saltol to improve salt tolerance in rice. Furthermore, the effective role of this method has been shown in crops such as wheat and maize for overcoming abiotic stresses, including salinity. However, MAS has limited efficiency for complex quantitative traits controlled by genes or QTLs with small effects. Today, more advanced approaches such as genomic selection (GS), CRISPR/Cas9-based genome editing, and high-throughput phenotyping (HTP) are being employed as complementary strategies to enhance the precision and speed of breeding programs aimed at developing varieties tolerant to environmental stresses such as salinity. Conclusion: Modern plant breeding tools such as marker-assisted selection, genome-wide association studies (GWAS), and particularly omics technologies (transcriptomics, proteomics, and metabolomics) as well as genome editing have revolutionized the process of identifying and transferring desirable genes into crop plants. These technologies enable gene pyramiding and the simultaneous transfer of multiple salt-tolerance genes with high precision and speed. Introduction: Salinity, as one of the most significant limiting factors for the growth and production of strategic crops such as wheat, rice, and maize, poses a serious threat to global food security. Given the high cost and time-consuming nature of physical remediation of saline soils, developing tolerant varieties through breeding programs is the most effective and economical approach to addressing this challenge. In this regard, understanding the molecular and genetic mechanisms of salt tolerance is essential for generating new, salt-tolerant genotypes. The aim of the present study was to review recent advances and investigate the application of modern breeding technologies to accelerate the development of salt-tolerant varieties in crop plants, particularly cereals. Materials and Methods: This review study systematically describes the application of novel biotechnologies including the integration of omics tools, genomic mapping, marker-assisted selection (MAS), and genome editing to efficiently transfer identified genes and QTLs into elite genotypes and to expedite breeding programs. Results and Discussion: Marker-assisted selection is an efficient breeding method that, instead of relying solely on phenotype, enables the selection of superior genotypes using DNA banding patterns at early stages of organism development. By reducing environmental influence, this approach enhances the accuracy and speed of breeding programs and significantly shortens the breeding cycle, which in classical methods may take approximately eight to ten years. The successful application of MAS has been demonstrated in transferring QTLs such as Saltol to improve salt tolerance in rice. Furthermore, the effective role of this method has been shown in crops such as wheat and maize for overcoming abiotic stresses, including salinity. However, MAS has limited efficiency for complex quantitative traits controlled by genes or QTLs with small effects. Today, more advanced approaches such as genomic selection (GS), CRISPR/Cas9-based genome editing, and high-throughput phenotyping (HTP) are being employed as complementary strategies to enhance the precision and speed of breeding programs aimed at developing varieties tolerant to environmental stresses such as salinity. Conclusion: Modern plant breeding tools such as marker-assisted selection, genome-wide association studies (GWAS), and particularly omics technologies (transcriptomics, proteomics, and metabolomics) as well as genome editing have revolutionized the process of identifying and transferring desirable genes into crop plants. These technologies enable gene pyramiding and the simultaneous transfer of multiple salt-tolerance genes with high precision and speed.

https://cr.guilan.ac.ir/article_9464_f19bb9b28b45356b6e20acd313fc960a.pdf