Univrsity of Tehran PressIranian Journal of Field Crop Science2008-481156420251222The Effect of Rice Residue and Vermicompost Fertilizer on Bean Yield in Rice- Bean Double CroppingThe Effect of Rice Residue and Vermicompost Fertilizer on Bean Yield in Rice- Bean Double Cropping11510552610.22059/ijfcs.2025.396682.655146FAAlieyehAbyatDepartment of Production Engineering and Plant Genetic,Faculty of Agriculture,Shahid Chamran University of Ahvaz, Ahvaz, Iran.AmirAynehbandDepartment of Production Engineering and Plant Genetic,Faculty of Agriculture,Shahid Chamran University of Ahvaz, Ahvaz, Iran.0000-0002-9144-455XEsfandiarFatehDepartment of Production Engineering and Plant Genetic,Faculty of Agriculture,Shahid Chamran University of Ahvaz, Ahvaz, Iran.Journal Article20250604<strong>Introduction. </strong>Legume production systems increasingly require sustainable soil amendments to balance productivity and ecological resilience. While vermicompost enhances soil fertility and rice residues improve organic matter, their synergistic effects on bean remain underexplored in arid agroecosystems. This study quantifies how graded vermicompost (0–10 tha<sup>-1</sup>) and rice residue incorporation (0–30%) optimize yield architecture in bean cultivation under Khuzestan's semi-arid conditions.<br /><strong>Materials and Methods. </strong>This experiment was conducted as a split plot experiment in a randomized complete block design (RCBD) with three replications in the crop year 2022-2023. The main factor was vermicompost consumption at three levels including zero (without vermicompost fertilizer), five and 10 tons per hectare and the secondary factor was rice residue at four levels including zero (no residue), 10%, 20%, and 30%. The rice field was located in DashteAzadegan area. Najafi rice was cultivated in this field in the summer of 2022. Plant height, seed number per square meter, number of pods per square meter, plant weight without pods per square meter, pod shell weight per square meter, seeds number per square meter, 100 seed weight, seed yield per hectare and biological yield per hectare were measured.<br /><strong>Results and Discussion.</strong> Results showed that the effect of vermicompost on plant height, plant weight, number of pods per square meter, 100 seed weight, seed weight, seed yield per hectare and biological yield per hectare was significant at the one percentage probability level. Also, effect of rice residue on plant height and seed yield per hectare at the five percentage probability level and on biological yield per hectare, was significant at the one percentage probability level. The intraction effect of vermicompost and rice residue on number of pods per square meter, plant weight, 100 seed weight, seed weight, biological yield per hectare was significant at the one percentage probability level but on seed yield per hectare was significant at the five percentage probability level. The results of mean comparison showed that the highest of bean plant height under the conditions of application of 20% of rice residues was observed with an amount of 85 cm and the lowest amount was observed under the conditions of application of 30% of rice residues with an amount of 72 cm. Also, the results of this study showed that the highest seed number per square meter was obtained by five tons per hectare of vermicompost and using 20% of rice residues (768 seeds) and the lowest seed number per square meter was belonged to the treatment of not using vermicompost and not using rice residues by 378 seeds. Based on the results of average comparing of traits, the highest amount of seed yield belonged to the treatment of using five tons per hectare of vermicompost and 20% of rice residues (8660 kgha<sup>-1</sup>). The lowest amount of seed yield was observed in the treatment of not using vermicompost and rice residues (2307 kgha<sup>-1</sup>). Also, the highest and the lowest amount of biological yield was observed in the treatment of five t ha<sup>-1</sup> of vermicompost and 20% of rice residues (19480 kgha<sup>-1</sup>) and the treatment of not using vermicompost and rice residues (7597 kgha<sup>-1</sup>), respectively.<br />The highest of pod number of per square meter, pod weight per square meter, plant weight without pods per square meter, pod shell weight per square meter, seeds number per square meter, 100 seed weight, seed yield per hectare and biological yield per hectare were observed by five t ha<sup>-1</sup> of vermicompost and the use of 20% of rice residues.<br /><br /><br /><br /><br /><strong>Conclusion. </strong>According to the results of the present experiment and the importance of achieving a high seed yield in the bean plant, it seems that the treatment of using five tons per hectare of vermicompost and the use of 20% of rice residues is a suitable treatment to achieve the high yield of this plant was used in the same weather conditions as the experimental site (Shadgan city) in Khuzestan province and other regions of the country is recommended<strong>Introduction. </strong>Legume production systems increasingly require sustainable soil amendments to balance productivity and ecological resilience. While vermicompost enhances soil fertility and rice residues improve organic matter, their synergistic effects on bean remain underexplored in arid agroecosystems. This study quantifies how graded vermicompost (0–10 tha<sup>-1</sup>) and rice residue incorporation (0–30%) optimize yield architecture in bean cultivation under Khuzestan's semi-arid conditions.<br /><strong>Materials and Methods. </strong>This experiment was conducted as a split plot experiment in a randomized complete block design (RCBD) with three replications in the crop year 2022-2023. The main factor was vermicompost consumption at three levels including zero (without vermicompost fertilizer), five and 10 tons per hectare and the secondary factor was rice residue at four levels including zero (no residue), 10%, 20%, and 30%. The rice field was located in DashteAzadegan area. Najafi rice was cultivated in this field in the summer of 2022. Plant height, seed number per square meter, number of pods per square meter, plant weight without pods per square meter, pod shell weight per square meter, seeds number per square meter, 100 seed weight, seed yield per hectare and biological yield per hectare were measured.<br /><strong>Results and Discussion.</strong> Results showed that the effect of vermicompost on plant height, plant weight, number of pods per square meter, 100 seed weight, seed weight, seed yield per hectare and biological yield per hectare was significant at the one percentage probability level. Also, effect of rice residue on plant height and seed yield per hectare at the five percentage probability level and on biological yield per hectare, was significant at the one percentage probability level. The intraction effect of vermicompost and rice residue on number of pods per square meter, plant weight, 100 seed weight, seed weight, biological yield per hectare was significant at the one percentage probability level but on seed yield per hectare was significant at the five percentage probability level. The results of mean comparison showed that the highest of bean plant height under the conditions of application of 20% of rice residues was observed with an amount of 85 cm and the lowest amount was observed under the conditions of application of 30% of rice residues with an amount of 72 cm. Also, the results of this study showed that the highest seed number per square meter was obtained by five tons per hectare of vermicompost and using 20% of rice residues (768 seeds) and the lowest seed number per square meter was belonged to the treatment of not using vermicompost and not using rice residues by 378 seeds. Based on the results of average comparing of traits, the highest amount of seed yield belonged to the treatment of using five tons per hectare of vermicompost and 20% of rice residues (8660 kgha<sup>-1</sup>). The lowest amount of seed yield was observed in the treatment of not using vermicompost and rice residues (2307 kgha<sup>-1</sup>). Also, the highest and the lowest amount of biological yield was observed in the treatment of five t ha<sup>-1</sup> of vermicompost and 20% of rice residues (19480 kgha<sup>-1</sup>) and the treatment of not using vermicompost and rice residues (7597 kgha<sup>-1</sup>), respectively.<br />The highest of pod number of per square meter, pod weight per square meter, plant weight without pods per square meter, pod shell weight per square meter, seeds number per square meter, 100 seed weight, seed yield per hectare and biological yield per hectare were observed by five t ha<sup>-1</sup> of vermicompost and the use of 20% of rice residues.<br /><br /><br /><br /><br /><strong>Conclusion. </strong>According to the results of the present experiment and the importance of achieving a high seed yield in the bean plant, it seems that the treatment of using five tons per hectare of vermicompost and the use of 20% of rice residues is a suitable treatment to achieve the high yield of this plant was used in the same weather conditions as the experimental site (Shadgan city) in Khuzestan province and other regions of the country is recommendedhttps://ijfcs.ut.ac.ir/article_105526_23066835204edb4e1c3abd85101aab5c.pdfUnivrsity of Tehran PressIranian Journal of Field Crop Science2008-481156420251222Effects of Drought Stress on Sink Capacity and Grain-Filling Process in Wheat: Focus on Endosperm Cell Division CharacteristicsEffects of Drought Stress on Sink Capacity and Grain-Filling Process in Wheat: Focus on Endosperm Cell Division Characteristics173110508710.22059/ijfcs.2025.395511.655138FASara SadatAfjehAgronomy and Plant Breeding Department , College of Agriculture and Natural Resources, University of Tehran. Karaj. IranAliAhmadiAgronomy and Plant Breeding Department , College of Agriculture and Natural Resources, University of Tehran. Karaj. IranPouriaMostafaieAgronomy and Plant Breeding Department , College of Agriculture and Natural Resources, University of Tehran. Karaj. IranJournal Article20250520<strong>Introduction. </strong>Drought stress is a major environmental constraint on wheat (<em>Triticum aestivum</em> L.) productivity, especially in arid and semi-arid regions. It negatively impacts critical physiological processes during the reproductive stage, resulting in significant reductions in grain yield. Grain filling is a crucial and highly susceptible phase to drought stress, as it relies on a delicate balance between photosynthetic assimilate production and the sink strength of developing grains. Sink strength defined by the ability of developing grains to accumulate assimilates, is mainly determined by the endosperm cell division rate and the active cell division period. This study aimed to clarify the physiological mechanisms of grain yield reduction under drought stress in wheat, focusing on grain-filling dynamics, endosperm cell division, and sink capacity in two contrasting cultivars: Shoosh (drought-sensitive) and Hamoon (drought-tolerant).<br /><strong>Materials and Methods. </strong>The study was conducted as a factorial experiment based on a randomized complete block design (RCBD) with three blocks (replications). The experimental factors were as follows: (1) two spring bread wheat cultivars (Hamoon and Shoosh), and (2) two levels of moisture regimes, including well-watered (WW, 70% of field capacity) and drought stress (DS, 50% of field capacity), starting from the beginning of stem elongation (Zadoks growth stage 30) onwards. Measurements included grain yield per spike, grain number per spike, final grain weight, and several grain-filling parameters. Specifically, we examined endosperm cell number, cell division rate, active cell division period, grain-filling rate, and active grain-filling period. Sampling was done at regular intervals from anthesis (Zadoks growth stage 60) to physiological maturity (Zadoks growth stage 92) to create a comprehensive profile of grain development for each treatment. Curve-fitting models were used to determine cell division and grain-filling dynamics, and correlation analyses were performed to evaluate the relationships between physiological traits and final grain yield.<br /><strong>Results and Discussion. </strong>Our results demonstrated that drought stress adversely affected all grain-filling parameters, leading to significant yield losses, particularly in the drought-sensitive cultivar (Shoosh). The reduction in grain yield per spike was primarily due to a decline in final grain weight. This yield component was strongly associated with indicators of sink strength, especially endosperm cell number and grain-filling rate. The resistant cultivar (Hamoon) exhibited a more stable yield under drought stress by maintaining a higher cell division rate and a longer grain-filling duration. From four to 12 days after anthesis, the endosperm cell number was higher under drought conditions than under well-watered conditions, especially in the tolerant cultivar. This was linked to an early increase in the cell division rate and a slight improvement in the grain-filling rate, resulting in minor early increases in grain weight. The early occurrence of peak values for cell division and grain-filling rates may indicate a drought-escape strategy, where plants accelerate development to complete grain filling before water becomes critically limited. While this strategy offers temporary advantages, it often leads to smaller grains. In contrast, the gradual and sustained development observed in Hamoon suggests that drought tolerance enables continued grain filling under stress conditions. Notably, strong positive correlations between final grain weight and traits such as maximum grain-filling rate, endosperm cell number, and active cell division period highlight the critical role of sink capacity in determining wheat yield under drought stress. These relationships were consistent across treatments, confirming their significance as selection criteria for breeding.<br /><strong>Conclusion. </strong>The findings showed that drought stress effectively reduces wheat grain yield by disrupting physiological processes related to grain filling, including decreased rates and duration of endosperm cell division, grain-filling rate, and sink capacity. Meanwhile, compensatory responses such as an initial increase in cell division and grain-filling rates during the early stages of grain filling, especially in resistant cultivars, can be considered drought escape mechanisms. Although these responses temporarily enhance sink efficiency, they are inadequate to sustain final yield. The variation in responses among cultivars suggests that maintaining sink capacity during drought stress is crucial for plants' resilience to drought conditions. Accordingly, improving traits related to source and sink dynamics, particularly by selecting genotypes with more stable cell division capacity and effective grain-filling rates, can be an effective strategy in breeding and crop management programs to enhance the sustainability of wheat yields under water-limited conditions.<strong>Introduction. </strong>Drought stress is a major environmental constraint on wheat (<em>Triticum aestivum</em> L.) productivity, especially in arid and semi-arid regions. It negatively impacts critical physiological processes during the reproductive stage, resulting in significant reductions in grain yield. Grain filling is a crucial and highly susceptible phase to drought stress, as it relies on a delicate balance between photosynthetic assimilate production and the sink strength of developing grains. Sink strength defined by the ability of developing grains to accumulate assimilates, is mainly determined by the endosperm cell division rate and the active cell division period. This study aimed to clarify the physiological mechanisms of grain yield reduction under drought stress in wheat, focusing on grain-filling dynamics, endosperm cell division, and sink capacity in two contrasting cultivars: Shoosh (drought-sensitive) and Hamoon (drought-tolerant).<br /><strong>Materials and Methods. </strong>The study was conducted as a factorial experiment based on a randomized complete block design (RCBD) with three blocks (replications). The experimental factors were as follows: (1) two spring bread wheat cultivars (Hamoon and Shoosh), and (2) two levels of moisture regimes, including well-watered (WW, 70% of field capacity) and drought stress (DS, 50% of field capacity), starting from the beginning of stem elongation (Zadoks growth stage 30) onwards. Measurements included grain yield per spike, grain number per spike, final grain weight, and several grain-filling parameters. Specifically, we examined endosperm cell number, cell division rate, active cell division period, grain-filling rate, and active grain-filling period. Sampling was done at regular intervals from anthesis (Zadoks growth stage 60) to physiological maturity (Zadoks growth stage 92) to create a comprehensive profile of grain development for each treatment. Curve-fitting models were used to determine cell division and grain-filling dynamics, and correlation analyses were performed to evaluate the relationships between physiological traits and final grain yield.<br /><strong>Results and Discussion. </strong>Our results demonstrated that drought stress adversely affected all grain-filling parameters, leading to significant yield losses, particularly in the drought-sensitive cultivar (Shoosh). The reduction in grain yield per spike was primarily due to a decline in final grain weight. This yield component was strongly associated with indicators of sink strength, especially endosperm cell number and grain-filling rate. The resistant cultivar (Hamoon) exhibited a more stable yield under drought stress by maintaining a higher cell division rate and a longer grain-filling duration. From four to 12 days after anthesis, the endosperm cell number was higher under drought conditions than under well-watered conditions, especially in the tolerant cultivar. This was linked to an early increase in the cell division rate and a slight improvement in the grain-filling rate, resulting in minor early increases in grain weight. The early occurrence of peak values for cell division and grain-filling rates may indicate a drought-escape strategy, where plants accelerate development to complete grain filling before water becomes critically limited. While this strategy offers temporary advantages, it often leads to smaller grains. In contrast, the gradual and sustained development observed in Hamoon suggests that drought tolerance enables continued grain filling under stress conditions. Notably, strong positive correlations between final grain weight and traits such as maximum grain-filling rate, endosperm cell number, and active cell division period highlight the critical role of sink capacity in determining wheat yield under drought stress. These relationships were consistent across treatments, confirming their significance as selection criteria for breeding.<br /><strong>Conclusion. </strong>The findings showed that drought stress effectively reduces wheat grain yield by disrupting physiological processes related to grain filling, including decreased rates and duration of endosperm cell division, grain-filling rate, and sink capacity. Meanwhile, compensatory responses such as an initial increase in cell division and grain-filling rates during the early stages of grain filling, especially in resistant cultivars, can be considered drought escape mechanisms. Although these responses temporarily enhance sink efficiency, they are inadequate to sustain final yield. The variation in responses among cultivars suggests that maintaining sink capacity during drought stress is crucial for plants' resilience to drought conditions. Accordingly, improving traits related to source and sink dynamics, particularly by selecting genotypes with more stable cell division capacity and effective grain-filling rates, can be an effective strategy in breeding and crop management programs to enhance the sustainability of wheat yields under water-limited conditions.https://ijfcs.ut.ac.ir/article_105087_57fe129d62de2f24f8e0c6d0e4487c97.pdfUnivrsity of Tehran PressIranian Journal of Field Crop Science2008-481156420251222Integrated Application of Effective Microorganisms and Urea on Physiological, Biochemical, Photosynthetic Pigments Traits of Different Maize Cultivars under Water Deficit Stress ConditionsIntegrated Application of Effective Microorganisms and Urea on Physiological, Biochemical, Photosynthetic Pigments Traits of Different Maize Cultivars under Water Deficit Stress Conditions335110554010.22059/ijfcs.2025.395531.655139FAKamyabHosseiniDepartment of Agrotechnology, Faculty of Agriculture, University of Tarbiat Modares, Tehran, IranAliHeidarzadehDepartment of Agrotechnology, Faculty of Agriculture, University of Tarbiat Modares, Tehran, IranAliSorooshzadehDepartment of Agrotechnology, Faculty of Agriculture, University of Tarbiat Modares, Tehran, IranJournal Article20250519<strong>Introduction</strong><strong>. </strong>Maize (<em>Zea mays</em> L.) is one of the most important cereal crops globally, serving as a staple food and a key component in animal feed and biofuel production. However, its productivity is significantly influenced by environmental stresses, especially water deficit. Water scarcity affects the physiological and biochemical functioning of maize, leading to reduced photosynthetic efficiency and ultimately lower yield. In recent years, climate change and irregular rainfall patterns have increased the frequency of drought events, further emphasizing the need for sustainable agricultural practices to enhance crop resilience. Among the various approaches developed to mitigate drought stress in crops, the use of biological agents such as effective microorganisms (EM) has gained attention. EM consists of a mixture of beneficial microorganisms including nitrogen-fixing bacteria, phosphate-solubilizing bacteria, lactic acid bacteria, and yeasts, which improve plant growth by enhancing nutrient availability, root development, and stress resistance. Additionally, nitrogen (N) fertilizer plays a crucial role in plant metabolism, but its excessive use has resulted in serious environmental concerns such as groundwater contamination, eutrophication, and increased greenhouse gas emissions. Thus, the integration of EM with N fertilizer presents a promising strategy to reduce chemical input while maintaining or improving crop performance. This study aimed to evaluate the combined effects of EM and nitrogen fertilizer on photosynthetic pigments and biochemical traits of two maize cultivars under different irrigation regimes. The research specifically investigated how this integration can enhance maize tolerance to water deficit and improve physiological traits contributing to yield.<br /><strong>Materials and Methods.</strong><strong> </strong>The field experiment was conducted during the growing season of 2023 at the Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran. The experimental design was a split-split-plot layout based on a randomized complete block design (RCBD) with three replications. The main plots included three irrigation regimes based on soil field capacity: 85% (optimal irrigation), 70% (moderate water deficit), and 55% (severe water deficit). The subplots were assigned to three nutritional systems: Nitrogen fertilizer (urea), effective microorganisms (EM), and integrated treatment of EM + nitrogen fertilizer. The sub-subplots included two maize cultivars: S.C. 704, and TWC. 647. During the experiment, data were collected on several physiological and biochemical parameters including carotenoid content, intercellular to ambient CO₂ ratio (Ci/Ca), anthocyanins, total phenolics, proline, and seed yield. Standard laboratory protocols were followed for pigment extraction and biochemical analyses. Statistical analysis was performed using analysis of variance (ANOVA), and treatment means were compared using the least significant difference (LSD) test at a 5% significance level.<br /><strong>Results and Discussion. </strong>The results demonstrated that both irrigation regime and fertilizer treatment significantly affected the physiological and biochemical traits of maize. Under optimal irrigation (85% field capacity), the integrated application of EM and nitrogen fertilizer resulted in the highest carotenoid content and Ci/Ca ratio, particularly in the S.C. 704 cultivar. This indicates improved photosynthetic activity and gas exchange efficiency due to the synergistic effects of EM and nitrogen. Also, anthocyanin content was significantly increased (by 27%) in both cultivars under optimal irrigation when treated with the integrated EM + nitrogen fertilizer compared to the nitrogen-only control. This suggests enhanced antioxidant capacity under favorable water conditions. Under severe water deficit (55% field capacity), there was a notable increase in total phenolic and proline contents, with S.C. 704 showing a stronger biochemical response than TWC. 647. Phenolics play a critical role in plant defense against oxidative stress, while proline acts as an osmoprotectant, stabilizing proteins and membranes under drought conditions. The highest phenolic content was observed in S.C. 704 under the combined influence of water stress and EM application. Similarly, S.C. 704 accumulated significantly more proline than TWC. 647, confirming its superior drought tolerance. These results highlight the cultivar-dependent responses to stress and indicate the potential of EM in enhancing biochemical defense mechanisms. Seed yield was significantly influenced by the treatments. The highest yield (9,708 kgha⁻¹) was obtained from the S.C. 704 cultivar under optimal irrigation with the integrated EM and nitrogen treatment. This emphasizes the practical benefit of combining EM with chemical fertilizers to sustain or improve yield under ideal water availability. Overall, S.C. 704 consistently outperformed TWC. 647 in terms of pigment accumulation, stress-related biochemical traits, and yield, suggesting its suitability for cultivation under both optimal and stressful conditions when supported by integrated nutrient management.<br /><br /><br /><br /><br /><strong>Conclusion. </strong>The integration of effective microorganisms with nitrogen fertilizer proved to be a beneficial strategy for improving the physiological and biochemical traits, and maize yield under varying irrigation conditions. While the use of nitrogen fertilizer alone supports growth, combining it with EM enhances nutrient uptake, boosts antioxidant production, and strengthens drought resilience, especially in the S.C. 704 cultivar. Under optimal irrigation, the integrated treatment significantly improved carotenoid levels, anthocyanin content, and yield. Under severe water stress, EM application mitigated stress-induced damage by increasing phenolic and proline levels, again more notably in S.C. 704. These findings confirm the role of EM in enhancing maize tolerance to drought while offering an environmentally sustainable approach to reduce chemical fertilizer dependency. Given the global concerns about the environmental impacts of excessive fertilizer use, the combined application of EM and nitrogen represents a promising approach for sustainable maize production. Future studies should explore the long-term effects of this integration on soil health, microbial diversity, and yield stability across different agroecological zones.<strong>Introduction</strong><strong>. </strong>Maize (<em>Zea mays</em> L.) is one of the most important cereal crops globally, serving as a staple food and a key component in animal feed and biofuel production. However, its productivity is significantly influenced by environmental stresses, especially water deficit. Water scarcity affects the physiological and biochemical functioning of maize, leading to reduced photosynthetic efficiency and ultimately lower yield. In recent years, climate change and irregular rainfall patterns have increased the frequency of drought events, further emphasizing the need for sustainable agricultural practices to enhance crop resilience. Among the various approaches developed to mitigate drought stress in crops, the use of biological agents such as effective microorganisms (EM) has gained attention. EM consists of a mixture of beneficial microorganisms including nitrogen-fixing bacteria, phosphate-solubilizing bacteria, lactic acid bacteria, and yeasts, which improve plant growth by enhancing nutrient availability, root development, and stress resistance. Additionally, nitrogen (N) fertilizer plays a crucial role in plant metabolism, but its excessive use has resulted in serious environmental concerns such as groundwater contamination, eutrophication, and increased greenhouse gas emissions. Thus, the integration of EM with N fertilizer presents a promising strategy to reduce chemical input while maintaining or improving crop performance. This study aimed to evaluate the combined effects of EM and nitrogen fertilizer on photosynthetic pigments and biochemical traits of two maize cultivars under different irrigation regimes. The research specifically investigated how this integration can enhance maize tolerance to water deficit and improve physiological traits contributing to yield.<br /><strong>Materials and Methods.</strong><strong> </strong>The field experiment was conducted during the growing season of 2023 at the Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran. The experimental design was a split-split-plot layout based on a randomized complete block design (RCBD) with three replications. The main plots included three irrigation regimes based on soil field capacity: 85% (optimal irrigation), 70% (moderate water deficit), and 55% (severe water deficit). The subplots were assigned to three nutritional systems: Nitrogen fertilizer (urea), effective microorganisms (EM), and integrated treatment of EM + nitrogen fertilizer. The sub-subplots included two maize cultivars: S.C. 704, and TWC. 647. During the experiment, data were collected on several physiological and biochemical parameters including carotenoid content, intercellular to ambient CO₂ ratio (Ci/Ca), anthocyanins, total phenolics, proline, and seed yield. Standard laboratory protocols were followed for pigment extraction and biochemical analyses. Statistical analysis was performed using analysis of variance (ANOVA), and treatment means were compared using the least significant difference (LSD) test at a 5% significance level.<br /><strong>Results and Discussion. </strong>The results demonstrated that both irrigation regime and fertilizer treatment significantly affected the physiological and biochemical traits of maize. Under optimal irrigation (85% field capacity), the integrated application of EM and nitrogen fertilizer resulted in the highest carotenoid content and Ci/Ca ratio, particularly in the S.C. 704 cultivar. This indicates improved photosynthetic activity and gas exchange efficiency due to the synergistic effects of EM and nitrogen. Also, anthocyanin content was significantly increased (by 27%) in both cultivars under optimal irrigation when treated with the integrated EM + nitrogen fertilizer compared to the nitrogen-only control. This suggests enhanced antioxidant capacity under favorable water conditions. Under severe water deficit (55% field capacity), there was a notable increase in total phenolic and proline contents, with S.C. 704 showing a stronger biochemical response than TWC. 647. Phenolics play a critical role in plant defense against oxidative stress, while proline acts as an osmoprotectant, stabilizing proteins and membranes under drought conditions. The highest phenolic content was observed in S.C. 704 under the combined influence of water stress and EM application. Similarly, S.C. 704 accumulated significantly more proline than TWC. 647, confirming its superior drought tolerance. These results highlight the cultivar-dependent responses to stress and indicate the potential of EM in enhancing biochemical defense mechanisms. Seed yield was significantly influenced by the treatments. The highest yield (9,708 kgha⁻¹) was obtained from the S.C. 704 cultivar under optimal irrigation with the integrated EM and nitrogen treatment. This emphasizes the practical benefit of combining EM with chemical fertilizers to sustain or improve yield under ideal water availability. Overall, S.C. 704 consistently outperformed TWC. 647 in terms of pigment accumulation, stress-related biochemical traits, and yield, suggesting its suitability for cultivation under both optimal and stressful conditions when supported by integrated nutrient management.<br /><br /><br /><br /><br /><strong>Conclusion. </strong>The integration of effective microorganisms with nitrogen fertilizer proved to be a beneficial strategy for improving the physiological and biochemical traits, and maize yield under varying irrigation conditions. While the use of nitrogen fertilizer alone supports growth, combining it with EM enhances nutrient uptake, boosts antioxidant production, and strengthens drought resilience, especially in the S.C. 704 cultivar. Under optimal irrigation, the integrated treatment significantly improved carotenoid levels, anthocyanin content, and yield. Under severe water stress, EM application mitigated stress-induced damage by increasing phenolic and proline levels, again more notably in S.C. 704. These findings confirm the role of EM in enhancing maize tolerance to drought while offering an environmentally sustainable approach to reduce chemical fertilizer dependency. Given the global concerns about the environmental impacts of excessive fertilizer use, the combined application of EM and nitrogen represents a promising approach for sustainable maize production. Future studies should explore the long-term effects of this integration on soil health, microbial diversity, and yield stability across different agroecological zones.https://ijfcs.ut.ac.ir/article_105540_4ea691e224faff666e997f9021bf5986.pdfUnivrsity of Tehran PressIranian Journal of Field Crop Science2008-481156420251222The Effect of Salt Stress on Wheat Grain Traits using Advanced Imaging TechnologyThe Effect of Salt Stress on Wheat Grain Traits using Advanced Imaging Technology537410509010.22059/ijfcs.2025.395914.655142FAMujtabaSadaatDepartment of Agronomy and Plant Breeding, Faculty of Agriculture, University of Tehran, Karaj, Iran.Mohammad RezaBihamtaDepartment of Agronomy and Plant Breeding, Faculty of Agriculture, University of Tehran, Karaj, Iran.ValiollahMohammadiDepartment of Agronomy and Plant Breeding, Faculty of Agriculture, University of Tehran, Karaj, Iran.MehrdadMahloojiAgriculture and Natural Resources Research Center of Isfahan, Isfahan, Iran.Journal Article20250524<strong>Introduction. </strong>Wheat (<em>Triticum aestivum</em> L.) remains a cornerstone of global food security, yet its productivity is increasingly threatened by soil salinity, which affects over 20% of irrigated lands worldwide. Salinity induces osmotic stress and ion toxicity, leading to a drastic reduction in grain filling duration and efficiency. While traditional breeding focuses on yield components like thousand-kernel weight (TKW), these metrics provide a "black-box" view of grain development. They fail to capture the nuanced changes in grain architecture—such as thickness, sphericity, and surface roughness—which are critical indicators of the physiological health of the plant during the grain-filling stage. The fundamental "Knowledge Gap" in current wheat research lies in the lack of high-throughput, multi-dimensional phenotyping tools capable of screening large germplasm collections. Manual measurements are prone to error and ignore the 3D geometry of the grain. This study addresses this gap by employing a 3D multi-view digital imaging platform to profile the morphometric responses of a massive panel of 320 wheat genotypes. The significance of this study lies in its ability to transition from simple yield-based selection to "Morpho-digital selection," allowing breeders to identify salt-tolerant genotypes based on the stability of their grain architecture rather than just final mass. The objective was to quantify the impact of progressive salinity on 3D grain traits and to establish a diagnostic model using multivariate statistical approaches to identify elite salt-tolerant germplasm.
<strong>Materials and Methods. </strong>The experimental germplasm consisted of a diverse diversity panel of 320 bread wheat genotypes, comprising 108 modern commercial cultivars and 212 Iranian landraces, representing a wide range of genetic plasticity. The research was conducted at the Kabutarabad Agricultural Research Station, Isfahan, Iran (32°99′N, 51°17′E, 1545 m a.s.l.) during the 2022–2023 season. The field layout followed an alpha-lattice design with two replications. Two distinct irrigation regimes were established: A baseline salinity level (S1= 6 dSm<sup>-1</sup>), which represents the prevailing soil conditions in arid regions, and an elevated salinity stress level (S2= 10 dSm<sup>-1</sup>) to simulate severe stress. Upon physiological maturity, grains were harvested and prepared for high-throughput phenotyping. A standardized imaging pipeline was developed using a Canon EOS 250D digital camera (24.1 MP) mounted on a controlled-lighting rig. For each genotype, grains were imaged from three orthogonal perspectives: dorsal, lateral, and vertical. This multi-view approach allowed for the extraction of 3D-like volumetric data. Image processing was performed using a custom Python script utilizing the OpenCV (Open Computer Vision) and SciPy libraries. The algorithm performed automated thresholding, contour detection, and feature extraction. Measured traits included primary dimensions (Length/Feret, Width/Breadth, Thickness), area-based indices (Area_D, Area_L, Area_V), and derived geometric parameters (Volume, Aspect Ratio, Compactness, and Centroid Affinity Index). Statistical rigor was ensured through a multi-tiered analysis: ANOVA was performed to determine the significance of Genotype × Environment (G×E) interactions. Linear Discriminant Analysis (LDA) was utilized for group classification, Exploratory Factor Analysis (EFA) for data reduction, and Path Analysis to model the causal relationships between digital traits and final grain mass (TKW). All analyses were conducted in R and SPSS (v.26).
<strong>Results and Discussion. </strong>The results provided an unprecedented look into the "morphological changes" of wheat grains under severe salinity. ANOVA revealed that salinity stress, genotype, and their interaction (G×I) had a highly significant (<em>p</em>< 0.0001) impact on all digital morphometric traits. On average, severe salinity (10 dSm<sup>-1</sup>) led to a 31.7% reduction in grain volume, which was more pronounced than the reductions in length (26.3%) and width (22.1%). This indicates that salinity primarily inhibits the lateral and vertical expansion of the endosperm, leading to "shriveled" grains. The reduction in mean grain circumference from 43.43 mm to 32.05 mm underscores the inhibition of cell expansion in the grain coat under osmotic pressure. A pivotal finding was the relationship between 3D traits and yield. Correlation analysis showed that while all dimensions decreased, grain thickness emerged as the most reliable predictor of mass, showing a near-perfect correlation with TKW (r= 0.966, <em>p</em>< 0.01). This suggests that in salinity-stressed environments, the "thickness" of the grain is a proxy for the plant's ability to maintain sink strength. Exploratory Factor Analysis (EFA) successfully reduced the complex dataset into four latent factors—Size, Shape/Symmetry, Surface Roughness, and Compactness—explaining 83.5% of the total phenotypic variance. This categorization proves that salinity does not just make grains smaller; it fundamentally alters their geometric symmetry and surface texture. The Linear Discriminant Analysis (LDA) model demonstrated extraordinary diagnostic power, classifying genotypes into S1 and S2 groups with 96% accuracy. The high discriminant coefficients for Area_D and the Concentricity Index (CAI) suggest that these digital traits can serve as "bio-signatures" for salinity stress. Furthermore, Path Analysis elucidated the internal mechanism of yield loss: grain volume (Vol_V) exerted the largest direct positive effect on TKW (β= 0.95), acting as a central mediator for all other dimensional traits. Interestingly, the negative direct effect of thickness on TKW in the path model (β= –0.11), despite its high raw correlation, suggests a physiological trade-off where the plant sacrifices grain sphericity to maintain some level of mass under stress. Compared to previous studies (e.g., Zhang <em>et al</em>., 2022) which focused on 2D measurements, our 3D multi-view approach captured the "cylindricity" and "volume" more accurately, explaining an additional 15-20% of the variance in grain weight. The identification of the "Ohadi" cultivar (LDA score= 4.678) as a top performer highlights the potential of using Iranian landrace genetics to improve the resilience of modern cultivars.
<strong>Conclusion. </strong>This study revealed that salinity stress disrupts the 3D architecture of the wheat grain in a predictable and quantifiable manner. Grain thickness and volume were identified as the most critical digital biomarkers for salinity tolerance. The 3D multi-view imaging pipeline developed here offers a non-destructive, rapid, and cost-effective alternative to traditional lab-based measurements. We recommend that breeding programs integrate "Area_D" and "Concentricity Index" into their selection indices to screen for genotypes that maintain grain filling integrity under high-salinity environments. Future research could link these digital phenotypes with SNP markers through Genome-Wide Association Studies (GWAS) to uncover the underlying genetic loci.<strong>Introduction. </strong>Wheat (<em>Triticum aestivum</em> L.) remains a cornerstone of global food security, yet its productivity is increasingly threatened by soil salinity, which affects over 20% of irrigated lands worldwide. Salinity induces osmotic stress and ion toxicity, leading to a drastic reduction in grain filling duration and efficiency. While traditional breeding focuses on yield components like thousand-kernel weight (TKW), these metrics provide a "black-box" view of grain development. They fail to capture the nuanced changes in grain architecture—such as thickness, sphericity, and surface roughness—which are critical indicators of the physiological health of the plant during the grain-filling stage. The fundamental "Knowledge Gap" in current wheat research lies in the lack of high-throughput, multi-dimensional phenotyping tools capable of screening large germplasm collections. Manual measurements are prone to error and ignore the 3D geometry of the grain. This study addresses this gap by employing a 3D multi-view digital imaging platform to profile the morphometric responses of a massive panel of 320 wheat genotypes. The significance of this study lies in its ability to transition from simple yield-based selection to "Morpho-digital selection," allowing breeders to identify salt-tolerant genotypes based on the stability of their grain architecture rather than just final mass. The objective was to quantify the impact of progressive salinity on 3D grain traits and to establish a diagnostic model using multivariate statistical approaches to identify elite salt-tolerant germplasm.
<strong>Materials and Methods. </strong>The experimental germplasm consisted of a diverse diversity panel of 320 bread wheat genotypes, comprising 108 modern commercial cultivars and 212 Iranian landraces, representing a wide range of genetic plasticity. The research was conducted at the Kabutarabad Agricultural Research Station, Isfahan, Iran (32°99′N, 51°17′E, 1545 m a.s.l.) during the 2022–2023 season. The field layout followed an alpha-lattice design with two replications. Two distinct irrigation regimes were established: A baseline salinity level (S1= 6 dSm<sup>-1</sup>), which represents the prevailing soil conditions in arid regions, and an elevated salinity stress level (S2= 10 dSm<sup>-1</sup>) to simulate severe stress. Upon physiological maturity, grains were harvested and prepared for high-throughput phenotyping. A standardized imaging pipeline was developed using a Canon EOS 250D digital camera (24.1 MP) mounted on a controlled-lighting rig. For each genotype, grains were imaged from three orthogonal perspectives: dorsal, lateral, and vertical. This multi-view approach allowed for the extraction of 3D-like volumetric data. Image processing was performed using a custom Python script utilizing the OpenCV (Open Computer Vision) and SciPy libraries. The algorithm performed automated thresholding, contour detection, and feature extraction. Measured traits included primary dimensions (Length/Feret, Width/Breadth, Thickness), area-based indices (Area_D, Area_L, Area_V), and derived geometric parameters (Volume, Aspect Ratio, Compactness, and Centroid Affinity Index). Statistical rigor was ensured through a multi-tiered analysis: ANOVA was performed to determine the significance of Genotype × Environment (G×E) interactions. Linear Discriminant Analysis (LDA) was utilized for group classification, Exploratory Factor Analysis (EFA) for data reduction, and Path Analysis to model the causal relationships between digital traits and final grain mass (TKW). All analyses were conducted in R and SPSS (v.26).
<strong>Results and Discussion. </strong>The results provided an unprecedented look into the "morphological changes" of wheat grains under severe salinity. ANOVA revealed that salinity stress, genotype, and their interaction (G×I) had a highly significant (<em>p</em>< 0.0001) impact on all digital morphometric traits. On average, severe salinity (10 dSm<sup>-1</sup>) led to a 31.7% reduction in grain volume, which was more pronounced than the reductions in length (26.3%) and width (22.1%). This indicates that salinity primarily inhibits the lateral and vertical expansion of the endosperm, leading to "shriveled" grains. The reduction in mean grain circumference from 43.43 mm to 32.05 mm underscores the inhibition of cell expansion in the grain coat under osmotic pressure. A pivotal finding was the relationship between 3D traits and yield. Correlation analysis showed that while all dimensions decreased, grain thickness emerged as the most reliable predictor of mass, showing a near-perfect correlation with TKW (r= 0.966, <em>p</em>< 0.01). This suggests that in salinity-stressed environments, the "thickness" of the grain is a proxy for the plant's ability to maintain sink strength. Exploratory Factor Analysis (EFA) successfully reduced the complex dataset into four latent factors—Size, Shape/Symmetry, Surface Roughness, and Compactness—explaining 83.5% of the total phenotypic variance. This categorization proves that salinity does not just make grains smaller; it fundamentally alters their geometric symmetry and surface texture. The Linear Discriminant Analysis (LDA) model demonstrated extraordinary diagnostic power, classifying genotypes into S1 and S2 groups with 96% accuracy. The high discriminant coefficients for Area_D and the Concentricity Index (CAI) suggest that these digital traits can serve as "bio-signatures" for salinity stress. Furthermore, Path Analysis elucidated the internal mechanism of yield loss: grain volume (Vol_V) exerted the largest direct positive effect on TKW (β= 0.95), acting as a central mediator for all other dimensional traits. Interestingly, the negative direct effect of thickness on TKW in the path model (β= –0.11), despite its high raw correlation, suggests a physiological trade-off where the plant sacrifices grain sphericity to maintain some level of mass under stress. Compared to previous studies (e.g., Zhang <em>et al</em>., 2022) which focused on 2D measurements, our 3D multi-view approach captured the "cylindricity" and "volume" more accurately, explaining an additional 15-20% of the variance in grain weight. The identification of the "Ohadi" cultivar (LDA score= 4.678) as a top performer highlights the potential of using Iranian landrace genetics to improve the resilience of modern cultivars.
<strong>Conclusion. </strong>This study revealed that salinity stress disrupts the 3D architecture of the wheat grain in a predictable and quantifiable manner. Grain thickness and volume were identified as the most critical digital biomarkers for salinity tolerance. The 3D multi-view imaging pipeline developed here offers a non-destructive, rapid, and cost-effective alternative to traditional lab-based measurements. We recommend that breeding programs integrate "Area_D" and "Concentricity Index" into their selection indices to screen for genotypes that maintain grain filling integrity under high-salinity environments. Future research could link these digital phenotypes with SNP markers through Genome-Wide Association Studies (GWAS) to uncover the underlying genetic loci.https://ijfcs.ut.ac.ir/article_105090_975fe9bf3a87416582b158c5e4655744.pdfUnivrsity of Tehran PressIranian Journal of Field Crop Science2008-481156420251222The Effect of Different Irrigation Regimes on Yield and Water Use Efficiency of 10 Quinoa Genotypes in Karaj RegionThe Effect of Different Irrigation Regimes on Yield and Water Use Efficiency of 10 Quinoa Genotypes in Karaj Region759110508810.22059/ijfcs.2025.395547.655140FAAzamJamshidizadehDepartment of Agronomy and plant breeding, College of Agriculture and Natural Resources, Tehran University, Karaj, Iran.AliAhmadiDepartment of Agronomy and plant breeding, College of Agriculture and Natural Resources, Tehran University, Karaj, Iran.MahmoudBagheriAgricultural Research, Education and Extension Organization (AREEO), Seed and Plant Improvement Institute, Karaj, IranJournal Article20250522<strong>Introduction. </strong>Drought is a global challenge and one of the most significant environmental stresses affecting agricultural productivity. To optimize water resource use in agriculture, cultivating drought-resistant species is crucial, as it directly affects food and water security. Quinoa (<em>Chenopodium quinoa</em> Willd.), a member of the Amaranthaceae family, is among the most nutritious grain crops (Ruiz <em>et al</em>., 2014). Due to its high nutritional value (Fuentes & Paredes Gonzales, 2013) and tolerance to adverse environmental conditions (Vega Gálvez <em>et al</em>., 2010), quinoa has been identified as a promising alternative to traditional cereals. While initial studies have explored the performance and adaptability of various quinoa genotypes in the country, limited information is available on the optimal soil moisture levels for maximizing yield and water use efficiency (WUE) for these genotypes.
<strong>Materials and Methods</strong>. This study was conducted during the 2020–2021 cropping season at the research farm of the Faculty of Agriculture and Natural Resources, University of Tehran. The objective was to determine the optimal soil moisture levels for achieving maximum yield and water use efficiency across different quinoa genotypes. Sowing was done in mid-August under dry tillage conditions. Seeds were sown at a depth of 1–2 cm, and the first irrigation was applied immediately after planting. Each subplot consisted of three 3-meter rows, spaced 50 cm apart, with 10 cm between plants. The experiment followed a split-plot design within a randomized complete block design (RCBD) with three replications. The main plots consisted of four irrigation treatments based on cumulative pan evaporation levels: 90 mm (control), 110 mm, 130 mm, and 150 mm. The subplots contained ten quinoa genotypes: Titicaca, Giza1, Atlas, Blanka, Kancolla, Marangani, Q1, Q3, Q12, and Q29. Measured traits included grain yield, thousand-grain weight, biological yield, harvest index (HI), plant height, inflorescence length, dry weight of plant and inflorescence, and water use efficiency. Drought-sensitive and drought-tolerant genotypes were identified based on the yield reduction under stress compared to the control (YP - YS) as Hossain <em>et al.</em> (1990). Data analysis, including ANOVA and mean comparisons was conducted using SAS software version 4.9.
<strong>Results and Discussion</strong>. The interaction between irrigation level and genotype significantly affected all measured traits. The greatest yield reductions under the 150 mm moisture level were observed in the Atlas, Blanka, and Kancolla genotypes, with decreases of 68%, 68%, and 67%, respectively, categorizing them as drought-sensitive. Among these, Atlas showed the highest yield reduction even at the 130 mm level, identifying it as the most drought-sensitive genotype. Conversely, Q1 and Marangani exhibited the lowest yield reductions under water stress, and if "confirmed in long-term studies", they can be classified as drought-tolerant genotypes. Atlas also performed poorly across all growth parameters under both normal and drought conditions. In terms of plant height under control conditions, Kancolla, Marangani, and Q3 genotypes exhibited the greatest values. The highest dry weights of both plant and inflorescence, as well as the maximum thousand-grain weight, were recorded for Kancolla under control conditions. The highest harvest index values were observed in Titicaca (47.74%) and Giza1 (45.87%) at the 90 mm level, while Atlas and Blanka had the lowest HI values under both control and severe water deficit conditions. Regarding water use efficiency, the Q1, Q12, Q29, Giza1, and Marangani genotypes exhibited the highest WUE values at the 150 mm moisture level. These findings are consistent with previous studies reporting that drought stress during the reproductive stage reduced grain yield and its components (Geerts <em>et al</em>., 2008; Gámez <em>et al</em>., 2019; Farooq <em>et al</em>., 2009). In this study, grain yield variations were primarily attributed to changes in inflorescence dry weight and thousand-grain weight.
<strong>Conclusions.</strong> Overall, the results demonstrated that quinoa growth, yield, and water use efficiency are significantly influenced by soil moisture levels. Under control conditions (90 mm), Kancolla, Titicaca, Q12, and Giza1 genotypes showed the highest grain yields. Atlas exhibited the highest yield reduction (68%) and was the least productive genotype across all conditions. Q1 was identified as the most drought-tolerant genotype, with minimal yield reduction and the highest WUE (2.20 kgm<sup>-</sup>³) under the 150 mm treatment. Optimal balance between yield and WUE was achieved in Kancolla at 90 mm, Titicaca at 110 mm, and Q1 at both 130 mm and 150 mm. The improved WUE was observed in quinoa under drought stress confirms its strong adaptability to adverse environmental conditions. Efficient management of irrigation in quinoa cultivation can serve as a strategic approach to mitigate water scarcity while maintaining agricultural productivity.<strong>Introduction. </strong>Drought is a global challenge and one of the most significant environmental stresses affecting agricultural productivity. To optimize water resource use in agriculture, cultivating drought-resistant species is crucial, as it directly affects food and water security. Quinoa (<em>Chenopodium quinoa</em> Willd.), a member of the Amaranthaceae family, is among the most nutritious grain crops (Ruiz <em>et al</em>., 2014). Due to its high nutritional value (Fuentes & Paredes Gonzales, 2013) and tolerance to adverse environmental conditions (Vega Gálvez <em>et al</em>., 2010), quinoa has been identified as a promising alternative to traditional cereals. While initial studies have explored the performance and adaptability of various quinoa genotypes in the country, limited information is available on the optimal soil moisture levels for maximizing yield and water use efficiency (WUE) for these genotypes.
<strong>Materials and Methods</strong>. This study was conducted during the 2020–2021 cropping season at the research farm of the Faculty of Agriculture and Natural Resources, University of Tehran. The objective was to determine the optimal soil moisture levels for achieving maximum yield and water use efficiency across different quinoa genotypes. Sowing was done in mid-August under dry tillage conditions. Seeds were sown at a depth of 1–2 cm, and the first irrigation was applied immediately after planting. Each subplot consisted of three 3-meter rows, spaced 50 cm apart, with 10 cm between plants. The experiment followed a split-plot design within a randomized complete block design (RCBD) with three replications. The main plots consisted of four irrigation treatments based on cumulative pan evaporation levels: 90 mm (control), 110 mm, 130 mm, and 150 mm. The subplots contained ten quinoa genotypes: Titicaca, Giza1, Atlas, Blanka, Kancolla, Marangani, Q1, Q3, Q12, and Q29. Measured traits included grain yield, thousand-grain weight, biological yield, harvest index (HI), plant height, inflorescence length, dry weight of plant and inflorescence, and water use efficiency. Drought-sensitive and drought-tolerant genotypes were identified based on the yield reduction under stress compared to the control (YP - YS) as Hossain <em>et al.</em> (1990). Data analysis, including ANOVA and mean comparisons was conducted using SAS software version 4.9.
<strong>Results and Discussion</strong>. The interaction between irrigation level and genotype significantly affected all measured traits. The greatest yield reductions under the 150 mm moisture level were observed in the Atlas, Blanka, and Kancolla genotypes, with decreases of 68%, 68%, and 67%, respectively, categorizing them as drought-sensitive. Among these, Atlas showed the highest yield reduction even at the 130 mm level, identifying it as the most drought-sensitive genotype. Conversely, Q1 and Marangani exhibited the lowest yield reductions under water stress, and if "confirmed in long-term studies", they can be classified as drought-tolerant genotypes. Atlas also performed poorly across all growth parameters under both normal and drought conditions. In terms of plant height under control conditions, Kancolla, Marangani, and Q3 genotypes exhibited the greatest values. The highest dry weights of both plant and inflorescence, as well as the maximum thousand-grain weight, were recorded for Kancolla under control conditions. The highest harvest index values were observed in Titicaca (47.74%) and Giza1 (45.87%) at the 90 mm level, while Atlas and Blanka had the lowest HI values under both control and severe water deficit conditions. Regarding water use efficiency, the Q1, Q12, Q29, Giza1, and Marangani genotypes exhibited the highest WUE values at the 150 mm moisture level. These findings are consistent with previous studies reporting that drought stress during the reproductive stage reduced grain yield and its components (Geerts <em>et al</em>., 2008; Gámez <em>et al</em>., 2019; Farooq <em>et al</em>., 2009). In this study, grain yield variations were primarily attributed to changes in inflorescence dry weight and thousand-grain weight.
<strong>Conclusions.</strong> Overall, the results demonstrated that quinoa growth, yield, and water use efficiency are significantly influenced by soil moisture levels. Under control conditions (90 mm), Kancolla, Titicaca, Q12, and Giza1 genotypes showed the highest grain yields. Atlas exhibited the highest yield reduction (68%) and was the least productive genotype across all conditions. Q1 was identified as the most drought-tolerant genotype, with minimal yield reduction and the highest WUE (2.20 kgm<sup>-</sup>³) under the 150 mm treatment. Optimal balance between yield and WUE was achieved in Kancolla at 90 mm, Titicaca at 110 mm, and Q1 at both 130 mm and 150 mm. The improved WUE was observed in quinoa under drought stress confirms its strong adaptability to adverse environmental conditions. Efficient management of irrigation in quinoa cultivation can serve as a strategic approach to mitigate water scarcity while maintaining agricultural productivity.https://ijfcs.ut.ac.ir/article_105088_b89b311962f83cb27c0a4b2f15b04e57.pdfUnivrsity of Tehran PressIranian Journal of Field Crop Science2008-481156420251222Foliar Application of Iron, Urea, and Amino Acids on Yield and Yield Components of Safflower (Carthamus tinctorius L.) under Irrigation Withholding during the Reproductive StageFoliar Application of Iron, Urea, and Amino Acids on Yield and Yield Components of Safflower (Carthamus tinctorius L.) under Irrigation Withholding during the Reproductive Stage9310310508910.22059/ijfcs.2025.395809.655141FASajadSaediDepartment of Agrotechnology, Faculty of Agriculture, University of Tarbiat Modares, Tehran, IranSeyed Ali MohammadModarres-SanavyDepartment of Agrotechnology, Faculty of Agriculture, University of Tarbiat Modares, Tehran, IranAliHeidarzadehDepartment of Agrotechnology, Faculty of Agriculture, University of Tarbiat Modares, Tehran, IranHosseinSabourifardDepartment of Agricultural Science, National University of Skills (NUS), Tehran, IranJournal Article20250525<strong>Introduction</strong>. Drought is widely regarded as one of the most critical abiotic stresses that can substantially impair plant growth and productivity, posing a significant threat to global food security. It can lead to a reduction in crop yield by as much as 70%, depending on the intensity, duration, and timing of the stress. The mechanisms through which drought stress affects plants include interference with the uptake and translocation of nutrients, induction of oxidative stress via the overproduction of reactive oxygen species (ROS), and disturbance of vital physiological and biochemical processes such as photosynthesis, stomatal conductance, and carbohydrate metabolism. Safflower (<em>Carthamus tinctorius</em> L.), an oilseed crop characterized by its considerable adaptability to water-deficit conditions, is not immune to such stresses. Particularly during the reproductive phase, drought can cause significant declines in seed yield and associated agronomic traits. In recent years, foliar application of nutrients has gained attention as a potentially efficient and practical approach to enhance plant tolerance to drought, especially in agro-ecological zones like Iran, where water scarcity and nutrient-poor soils often coexist. Among the foliar nutrients, iron, urea, and amino acids have shown promise in enhancing plant resilience against environmental stresses, due to their roles in improving nutrient use efficiency, activating antioxidant defense mechanisms, supporting protein and enzyme synthesis, and ultimately improving growth and yield performance.<br /><strong>Materials and Methods. </strong>To investigate the potential of foliar-applied nutrients in alleviating the negative effects of drought stress, a comprehensive field experiment was conducted during the 2022–2023 growing season at the research farm of Tarbiat Modares University, Tehran, Iran. The experimental design was a split-plot arrangement within a randomized complete block design (RCBD) with three replications. The main plot factor consisted of three irrigation regimes: (i) full irrigation throughout the season with no water restriction, (ii) water deficit imposed from the onset of the flowering stage (representing early drought stress), and (iii) water deficit imposed from the beginning of the seed-filling stage (representing late drought stress). The subplot factor included nine foliar spray treatments: (1) 6% iron chelate, (2) 1% urea solution, (3) commercial amino acid solution at 1 g L⁻¹, (4) iron + urea, (5) iron + amino acid, (6) urea + amino acid, (7) iron + urea + amino acid (triple combination), (8) distilled water spray (as a spraying control), and (9) no foliar spray (as a negative control). A wide range of morphological and yield-related traits were measured to evaluate the effects of treatments. These traits included plant height, capitulum diameter and length, number of capitula per plant, number of seeds per capitulum, 1000-seed weight, biological yield, straw yield, grain yield, and harvest index.<br /><strong>Results and Discussion. </strong>The results showed that drought stress significantly affected several yield components, most notably the capitulum dimensions. Capitulum length and diameter were particularly sensitive to water stress. The maximum capitulum length (65.17 mm) was recorded under late drought stress (with water withheld during the grain-filling stage), indicating that safflower plants tend to elongate floral structures under mild terminal drought conditions. In contrast, the minimum capitulum length (41.16 mm) was observed under early drought stress imposed at the flowering stage. Similarly, the highest capitulum diameter (74.26 mm) was recorded in the full irrigation treatment, while the lowest (47.22 mm) was observed when drought was applied during flowering. Interestingly, plant height did not differ significantly among irrigation regimes, indicating that this trait may be less sensitive to short-term water deficits or more genetically stable. The application of foliar nutrients had a considerable effect on reproductive output. The combined application of iron, urea, and amino acids produced the highest number of capitula per plant (7.69), suggesting a synergistic effect among these compounds in promoting flower development and retention under stress conditions. Full irrigation consistently resulted in superior reproductive parameters, including the highest number of seeds per capitulum (99.37) and the greatest 1000-seed weight (79.46 g). Conversely, early drought stress significantly reduced these values to 62.19 seeds per capitulum and 39.09 g for 1000-seed weight, respectively. Total biological yield and straw yield were strongly influenced by both the irrigation regime and foliar nutrient treatment. The highest biological yield (12,328 kg ha⁻¹) and straw yield (10,444 kg ha⁻¹) were obtained from the combined application of urea and amino acids under the late drought stress regime. Notably, this treatment combination also resulted in the highest grain yield (2627.78 kg ha⁻¹), confirming its effectiveness in enhancing crop productivity under water-limited conditions. In contrast, the lowest grain yield (1066.67 kg ha⁻¹) was recorded in the unsprayed control under drought, highlighting the detrimental effects of nutrient deficiency and water stress when unmitigated. Furthermore, the harvest index—a measure of resource allocation efficiency—was the highest under full irrigation and late drought stress, indicating that plants under these regimes were better able to convert assimilates into economic yield.<br /><strong>Conclusion. </strong>The findings of this study underscore the critical importance of mitigating drought stress during sensitive phenological stages such as flowering and seed filling in safflower cultivation. While drought during flowering proved particularly harmful to yield components, the strategic use of foliar nutrients was effective in alleviating the negative impacts of water stress. Among the tested treatments, the combined application of iron, urea, and amino acids showed the most promising results, particularly when the stress occurred at the grain-filling stage. This integrated foliar fertilization approach enhanced not only morphological traits and reproductive parameters but also led to significant improvements in grain yield and biomass production. Given the increasing frequency and severity of drought in arid and semi-arid regions, this research provides valuable insights into sustainable agronomic practices for maintaining safflower productivity under water-limited conditions. Future studies may explore the physiological and molecular mechanisms behind these improvements and evaluate the economic feasibility of large-scale implementation in different agro-climatic regions<strong>Introduction</strong>. Drought is widely regarded as one of the most critical abiotic stresses that can substantially impair plant growth and productivity, posing a significant threat to global food security. It can lead to a reduction in crop yield by as much as 70%, depending on the intensity, duration, and timing of the stress. The mechanisms through which drought stress affects plants include interference with the uptake and translocation of nutrients, induction of oxidative stress via the overproduction of reactive oxygen species (ROS), and disturbance of vital physiological and biochemical processes such as photosynthesis, stomatal conductance, and carbohydrate metabolism. Safflower (<em>Carthamus tinctorius</em> L.), an oilseed crop characterized by its considerable adaptability to water-deficit conditions, is not immune to such stresses. Particularly during the reproductive phase, drought can cause significant declines in seed yield and associated agronomic traits. In recent years, foliar application of nutrients has gained attention as a potentially efficient and practical approach to enhance plant tolerance to drought, especially in agro-ecological zones like Iran, where water scarcity and nutrient-poor soils often coexist. Among the foliar nutrients, iron, urea, and amino acids have shown promise in enhancing plant resilience against environmental stresses, due to their roles in improving nutrient use efficiency, activating antioxidant defense mechanisms, supporting protein and enzyme synthesis, and ultimately improving growth and yield performance.<br /><strong>Materials and Methods. </strong>To investigate the potential of foliar-applied nutrients in alleviating the negative effects of drought stress, a comprehensive field experiment was conducted during the 2022–2023 growing season at the research farm of Tarbiat Modares University, Tehran, Iran. The experimental design was a split-plot arrangement within a randomized complete block design (RCBD) with three replications. The main plot factor consisted of three irrigation regimes: (i) full irrigation throughout the season with no water restriction, (ii) water deficit imposed from the onset of the flowering stage (representing early drought stress), and (iii) water deficit imposed from the beginning of the seed-filling stage (representing late drought stress). The subplot factor included nine foliar spray treatments: (1) 6% iron chelate, (2) 1% urea solution, (3) commercial amino acid solution at 1 g L⁻¹, (4) iron + urea, (5) iron + amino acid, (6) urea + amino acid, (7) iron + urea + amino acid (triple combination), (8) distilled water spray (as a spraying control), and (9) no foliar spray (as a negative control). A wide range of morphological and yield-related traits were measured to evaluate the effects of treatments. These traits included plant height, capitulum diameter and length, number of capitula per plant, number of seeds per capitulum, 1000-seed weight, biological yield, straw yield, grain yield, and harvest index.<br /><strong>Results and Discussion. </strong>The results showed that drought stress significantly affected several yield components, most notably the capitulum dimensions. Capitulum length and diameter were particularly sensitive to water stress. The maximum capitulum length (65.17 mm) was recorded under late drought stress (with water withheld during the grain-filling stage), indicating that safflower plants tend to elongate floral structures under mild terminal drought conditions. In contrast, the minimum capitulum length (41.16 mm) was observed under early drought stress imposed at the flowering stage. Similarly, the highest capitulum diameter (74.26 mm) was recorded in the full irrigation treatment, while the lowest (47.22 mm) was observed when drought was applied during flowering. Interestingly, plant height did not differ significantly among irrigation regimes, indicating that this trait may be less sensitive to short-term water deficits or more genetically stable. The application of foliar nutrients had a considerable effect on reproductive output. The combined application of iron, urea, and amino acids produced the highest number of capitula per plant (7.69), suggesting a synergistic effect among these compounds in promoting flower development and retention under stress conditions. Full irrigation consistently resulted in superior reproductive parameters, including the highest number of seeds per capitulum (99.37) and the greatest 1000-seed weight (79.46 g). Conversely, early drought stress significantly reduced these values to 62.19 seeds per capitulum and 39.09 g for 1000-seed weight, respectively. Total biological yield and straw yield were strongly influenced by both the irrigation regime and foliar nutrient treatment. The highest biological yield (12,328 kg ha⁻¹) and straw yield (10,444 kg ha⁻¹) were obtained from the combined application of urea and amino acids under the late drought stress regime. Notably, this treatment combination also resulted in the highest grain yield (2627.78 kg ha⁻¹), confirming its effectiveness in enhancing crop productivity under water-limited conditions. In contrast, the lowest grain yield (1066.67 kg ha⁻¹) was recorded in the unsprayed control under drought, highlighting the detrimental effects of nutrient deficiency and water stress when unmitigated. Furthermore, the harvest index—a measure of resource allocation efficiency—was the highest under full irrigation and late drought stress, indicating that plants under these regimes were better able to convert assimilates into economic yield.<br /><strong>Conclusion. </strong>The findings of this study underscore the critical importance of mitigating drought stress during sensitive phenological stages such as flowering and seed filling in safflower cultivation. While drought during flowering proved particularly harmful to yield components, the strategic use of foliar nutrients was effective in alleviating the negative impacts of water stress. Among the tested treatments, the combined application of iron, urea, and amino acids showed the most promising results, particularly when the stress occurred at the grain-filling stage. This integrated foliar fertilization approach enhanced not only morphological traits and reproductive parameters but also led to significant improvements in grain yield and biomass production. Given the increasing frequency and severity of drought in arid and semi-arid regions, this research provides valuable insights into sustainable agronomic practices for maintaining safflower productivity under water-limited conditions. Future studies may explore the physiological and molecular mechanisms behind these improvements and evaluate the economic feasibility of large-scale implementation in different agro-climatic regionshttps://ijfcs.ut.ac.ir/article_105089_5002e1b807823dc5d6455f86c3cf7bb7.pdfUnivrsity of Tehran PressIranian Journal of Field Crop Science2008-481156420251222Methyl Jasmonate and Chitosan Enhanced the Antioxidant Content of Calotropis procera Hairy RootMethyl Jasmonate and Chitosan Enhanced the Antioxidant Content of Calotropis procera Hairy Root10512010558910.22059/ijfcs.2025.390829.655131FAFatemeAliAskariDepartment of Agronomy and Plant Breeding, Faculty of Agriculture, and Natural Resources University of Tehran. karaj. Iran.ManizhehSabokdastDepartment of Agronomy and Plant Breeding Faculty of Agriculture and Natural Resorces University of Tehran. karaj. Iran.0000-0002-0403-2208Mohammad RezaNaghaviDepartment of Agronomy and Plant Breeding Faculty of Agriculture and Natural Resources, University of Tehran. karaj. Iran.Journal Article20250508<strong>Introduction.</strong><em> Calotropis procera</em>, a prominent medicinal plant native to the dry regions of Asia and Africa, is widely recognized for its medicinal properties. The plant is a rich source of bioactive compounds, particularly flavonoids, phenolic acids, and alkaloids, which are known for their anti-inflammatory, antioxidant, and anticancer properties. Given the increasing demand for these valuable compounds, the development of efficient <em>in vitro</em> propagation systems, especially hairy root culture, is crucial for enhancing the production of secondary metabolites. This has led to significant interest in exploring sustainable methods to scale up production without relying on wild plant populations. In this study, we aimed to establish an effective method for inducing and maintaining hairy root cultures of <em>C. procera</em>, to evaluate the growth curve and assess the effects of different elicitors on secondary metabolite production, particularly focusing on phenolic and flavonoid content and antioxidant activity.<br /><strong>Materials and Methods.</strong> The first step in the study involved seed germination and the preparation of explants. Seeds of <em>C. procera</em> were germinated in MS medium, and 30-day-old seedlings were used to prepare explants from different parts, including leaves, stems and, roots. The explants were then subjected to inoculation as pretreatment with <em>Rhizobium rhizogenes</em> (formerly <em>Agrobacterium rhizogenes</em>), a bacterium known for its ability to induce hairy roots in plants. The induction process was further optimized by analyzing the effect of bacterial strains and explant types on the efficiency of root induction.<br /><strong>Results and Discussion.</strong> Among the bacterial strains tested, <em>R. rhizogenes</em> strain LBA9402 exhibited the highest efficiency in hairy root induction, with leaf explants showing the most significant response. Following inoculation, hairy roots were successfully induced and confirmed by PCR analysis, targeting the <em>rolB</em> gene, which is characteristic of transgenic hairy roots. PCR results showed that the <em>rolB</em> was amplified from the hairy roots, confirming the transgenic nature of the emerged roots. Results indicated that LBA9402 was the most effective strain, and leaf explants yielded the highest rate of root induction. The next phase of the study focused on the growth characteristics of the induced hairy roots. After several subcultures, the growth of the hairy roots was monitored in liquid MS medium containing 30 gL<sup>-1</sup> sugar, and fresh and dry weights were measured at regular intervals. The growth curve indicated that the highest fresh and dry weights of the hairy roots were recorded on days 28 and 24, respectively. These measurements were used to draw a growth curve for the selected hairy root line, which will be crucial for optimizing the production of secondary metabolites. In parallel with growth studies, the effects of two elicitors, chitosan and methyl jasmonate, on the production of phenolic compounds, flavonoids, and antioxidant activity in hairy root cultures were evaluated. The elicitors were applied at different concentrations and time intervals, and the total phenolic and flavonoid content were measured using standard assays. The results showed that methyl jasmonate at a concentration of 10 µM significantly increased the production of flavonoid compounds, especially within the first 24 hours. The results of total phenolic content measurement within 48 hours in the presence of 50 µM methyl jasmonate elicitor were higher (2927.22 µg GAE/g FW) than other groups and the highest antioxidant activity, as measured by the DPPH assay, was observed in the methyl jasmonate-treated roots, suggesting that this elicitor has a strong potential for enhancing the antioxidant properties of <em>C. procera</em> hairy roots.<br /><strong>Conclusion</strong>. This study contributes to the development of an efficient <em>in vitro</em> culture system for <em>C. procera</em>, providing insights into the optimization of conditions for hairy root induction and secondary metabolite production. The findings emphasize the role of bacterial strain selection, explant type, and elicitor treatments in enhancing the yield of valuable compounds. These results also suggest that methyl jasmonate is a potent elicitor for the production of phenolic and antioxidant compounds in <em>C. procera</em> hairy root cultures, making it a promising candidate for large-scale production of these bioactive metabolites. Further research is needed to explore the molecular mechanisms underlying the effects of elicitors on secondary metabolite biosynthesis and to optimize the production of other bioactive compounds in <em>C.</em> <em>procera</em>. These findings serve as an important prerequisite for future experiments in the field of hairy root cultivation, aimed at producing secondary metabolites in this valuable medicinal plant<strong>Introduction.</strong><em> Calotropis procera</em>, a prominent medicinal plant native to the dry regions of Asia and Africa, is widely recognized for its medicinal properties. The plant is a rich source of bioactive compounds, particularly flavonoids, phenolic acids, and alkaloids, which are known for their anti-inflammatory, antioxidant, and anticancer properties. Given the increasing demand for these valuable compounds, the development of efficient <em>in vitro</em> propagation systems, especially hairy root culture, is crucial for enhancing the production of secondary metabolites. This has led to significant interest in exploring sustainable methods to scale up production without relying on wild plant populations. In this study, we aimed to establish an effective method for inducing and maintaining hairy root cultures of <em>C. procera</em>, to evaluate the growth curve and assess the effects of different elicitors on secondary metabolite production, particularly focusing on phenolic and flavonoid content and antioxidant activity.<br /><strong>Materials and Methods.</strong> The first step in the study involved seed germination and the preparation of explants. Seeds of <em>C. procera</em> were germinated in MS medium, and 30-day-old seedlings were used to prepare explants from different parts, including leaves, stems and, roots. The explants were then subjected to inoculation as pretreatment with <em>Rhizobium rhizogenes</em> (formerly <em>Agrobacterium rhizogenes</em>), a bacterium known for its ability to induce hairy roots in plants. The induction process was further optimized by analyzing the effect of bacterial strains and explant types on the efficiency of root induction.<br /><strong>Results and Discussion.</strong> Among the bacterial strains tested, <em>R. rhizogenes</em> strain LBA9402 exhibited the highest efficiency in hairy root induction, with leaf explants showing the most significant response. Following inoculation, hairy roots were successfully induced and confirmed by PCR analysis, targeting the <em>rolB</em> gene, which is characteristic of transgenic hairy roots. PCR results showed that the <em>rolB</em> was amplified from the hairy roots, confirming the transgenic nature of the emerged roots. Results indicated that LBA9402 was the most effective strain, and leaf explants yielded the highest rate of root induction. The next phase of the study focused on the growth characteristics of the induced hairy roots. After several subcultures, the growth of the hairy roots was monitored in liquid MS medium containing 30 gL<sup>-1</sup> sugar, and fresh and dry weights were measured at regular intervals. The growth curve indicated that the highest fresh and dry weights of the hairy roots were recorded on days 28 and 24, respectively. These measurements were used to draw a growth curve for the selected hairy root line, which will be crucial for optimizing the production of secondary metabolites. In parallel with growth studies, the effects of two elicitors, chitosan and methyl jasmonate, on the production of phenolic compounds, flavonoids, and antioxidant activity in hairy root cultures were evaluated. The elicitors were applied at different concentrations and time intervals, and the total phenolic and flavonoid content were measured using standard assays. The results showed that methyl jasmonate at a concentration of 10 µM significantly increased the production of flavonoid compounds, especially within the first 24 hours. The results of total phenolic content measurement within 48 hours in the presence of 50 µM methyl jasmonate elicitor were higher (2927.22 µg GAE/g FW) than other groups and the highest antioxidant activity, as measured by the DPPH assay, was observed in the methyl jasmonate-treated roots, suggesting that this elicitor has a strong potential for enhancing the antioxidant properties of <em>C. procera</em> hairy roots.<br /><strong>Conclusion</strong>. This study contributes to the development of an efficient <em>in vitro</em> culture system for <em>C. procera</em>, providing insights into the optimization of conditions for hairy root induction and secondary metabolite production. The findings emphasize the role of bacterial strain selection, explant type, and elicitor treatments in enhancing the yield of valuable compounds. These results also suggest that methyl jasmonate is a potent elicitor for the production of phenolic and antioxidant compounds in <em>C. procera</em> hairy root cultures, making it a promising candidate for large-scale production of these bioactive metabolites. Further research is needed to explore the molecular mechanisms underlying the effects of elicitors on secondary metabolite biosynthesis and to optimize the production of other bioactive compounds in <em>C.</em> <em>procera</em>. These findings serve as an important prerequisite for future experiments in the field of hairy root cultivation, aimed at producing secondary metabolites in this valuable medicinal planthttps://ijfcs.ut.ac.ir/article_105589_7bffcb6fd41fff5c0b2f09afdcde75d4.pdfUnivrsity of Tehran PressIranian Journal of Field Crop Science2008-481156420251222Response of Germination Characteristics in Different Cleavers (Galium tricornutum) Populations to Stratification MethodsResponse of Germination Characteristics in Different Cleavers (Galium tricornutum) Populations to Stratification Methods12113210508410.22059/ijfcs.2025.384809.655110FAPooranFathiDept. of Crop Production and Genetic
Faculty of Agriculture, University of Kurdistan
Sanandaj, Iran.0009-0005-6861-1566IrajTahmasebiDep of crop protecture and genetic, factuly of agriculture, university of kurdestan, sanandaj, Iran.IrajNosratiDept. of Plant Production and Genetics,
Razi University,
Kermanshah
Iran.SirwanBabaeiDept. of Crop Production and Genetic
Faculty of Agriculture, University of Kurdistan
Sanandaj, Iran.Journal Article20241211<strong>Introduction. </strong><em>Galium tricornutum</em> is one of the most damaging weeds in wheat fields across the world. This plant reproduces through seeds, which are dormant and it has been proven that the degree of dormancy varies in different ecotypes collected from various environment. stratification is one of the common methods for overcoming seed dormancy in is <em>G. tricornutum</em>. Research has shown that <em>G. tricornutum</em> seeds have primary dormancy in which exposing seeds to low winter temperatures and favorable humidity in the spring may lead to breaking seed dormancy and germination. Hence, the aim of this study was to determine the efficacy stratification can be effective in removing the seed dormancy of <em>G. tricornutum</em> collected from western parts of Iran.<br /><strong>Materials and Methods. </strong>Seeds of <em>G. tricornutum</em> were collected from infested fields of some areas located in three provinces, including Western Azerbaijan (Heydarlu, Nazlu, Silvaneh), Kurdistan (Zafaraabaad, Saral, Gazneh, Sou, Kamyaran, Najafabad), Kermanshah (Kuzaran, Ravansar, Gilane-Gharb, Kermanshah), and Ilam (Abdanan, Sheshdar, Chovar, Ilam, Sarabeleh, Eyvan). After harvesting seeds, the presence of dormancy was confirmed in all ecotypes. The minimum and maximum time required for stratification to mitigate seed dormancy was also determined. Cold stratification treatments were applied at 4°C at 24, 48, and 72 hours. To apply hot-cold stratification, the same procedure was followed as for cold stratification, except that first, hot water at 80 degrees was used for three minutes. Finally, germination percentage, germination rate, germination index, and average germination time were measured.<br /><strong>Results and Discussion. </strong>The results of this study showed that the highest germination percentage was related to treatments of three minutes at 80 and immediately expose to 4 degrees Celsius for 72 hours in Gazneh from Kurdistan province (83%) and Abdanan from Ilam province (77%). Although Gazneh had the highest altitude among the studied areas, it was also one of the areas having the highest precipitation, and Abdanan was also one of the low-altitude areas with high temperature and rainfall, but its altitude was lower than other screened areas. Stratification had the greatest effect on the populations of Gilane-Gharb (60.48%), Gazneh (52.44%), and Abdanan (47.43%), respectively. Although the altitude of Gazneh is different from that of Gilane-Gharb and Abdanan, all three regions had an average rainfall of 320-530 mm and a temperature of 15-30 degrees Celsius higher than the other studied regions. The lowest germination percentage was observed in the Kuzran (9%) and Najafabad (11.71%) populations, which had the lowest average rainfall (160-220 mm) and average temperature (10-15°C). The populations of Kamyaran, Zafarabad, and Ivan did not differ significantly from each other. This is despite the fact that the altitude of Kamyaran and Ivan regions is close to each other, but Zafarabad is higher. These regions were also similar in terms of temperature and rainfall during the growing season. The highest germination rate was related to treatments of three minutes at 80 and immediately at 4 degrees Celsius for 72 hours in Gazneh from Kurdistan (20.23) and the lowest germination rate was achieved in the Najafabad seed population. There was significant difference in germination index among stratification treatments. The highest germination index was for Gazneh (9.38) and the lowest was for control treatment of Najafabad and Silvaneh (0). The highest means germination time was check of Silvaneh (non-treated) (12.86) and the lowest rate was related to treatments of three minutes at 80 and immediately at 4°C for 72 hours in Silvaneh (0.03) and control treatment in Njafabad (0.04).<br /><strong>Conclusion. </strong>Appropriate timing is necessary to control this weed without chemical methods. Chilling generally increased the germination of this species; therefore, the appropriate timing for controlling this plant species is early spring because natural chilling occurs in the fall and winter, and germination will occur in the spring with moisture. By stimulating seed germination using weed control methods, newly germinated <br /><em>G. tricornutum</em> seeds can be removed from the field before they compete with the crop using low-cost methods such as shallow plowing. The success rate of this timing varies due to the different sensitivity of seeds in each region to chilling, but it will have a positive effect in all regions studied. Research on this species are usually time-consuming due to seed dormancy, and researchers may not be very interested in studying this species for this reason. Therefore, a low-cost method that can break seed dormancy in a short period of time would be of great help to researchers. <strong>Introduction. </strong><em>Galium tricornutum</em> is one of the most damaging weeds in wheat fields across the world. This plant reproduces through seeds, which are dormant and it has been proven that the degree of dormancy varies in different ecotypes collected from various environment. stratification is one of the common methods for overcoming seed dormancy in is <em>G. tricornutum</em>. Research has shown that <em>G. tricornutum</em> seeds have primary dormancy in which exposing seeds to low winter temperatures and favorable humidity in the spring may lead to breaking seed dormancy and germination. Hence, the aim of this study was to determine the efficacy stratification can be effective in removing the seed dormancy of <em>G. tricornutum</em> collected from western parts of Iran.<br /><strong>Materials and Methods. </strong>Seeds of <em>G. tricornutum</em> were collected from infested fields of some areas located in three provinces, including Western Azerbaijan (Heydarlu, Nazlu, Silvaneh), Kurdistan (Zafaraabaad, Saral, Gazneh, Sou, Kamyaran, Najafabad), Kermanshah (Kuzaran, Ravansar, Gilane-Gharb, Kermanshah), and Ilam (Abdanan, Sheshdar, Chovar, Ilam, Sarabeleh, Eyvan). After harvesting seeds, the presence of dormancy was confirmed in all ecotypes. The minimum and maximum time required for stratification to mitigate seed dormancy was also determined. Cold stratification treatments were applied at 4°C at 24, 48, and 72 hours. To apply hot-cold stratification, the same procedure was followed as for cold stratification, except that first, hot water at 80 degrees was used for three minutes. Finally, germination percentage, germination rate, germination index, and average germination time were measured.<br /><strong>Results and Discussion. </strong>The results of this study showed that the highest germination percentage was related to treatments of three minutes at 80 and immediately expose to 4 degrees Celsius for 72 hours in Gazneh from Kurdistan province (83%) and Abdanan from Ilam province (77%). Although Gazneh had the highest altitude among the studied areas, it was also one of the areas having the highest precipitation, and Abdanan was also one of the low-altitude areas with high temperature and rainfall, but its altitude was lower than other screened areas. Stratification had the greatest effect on the populations of Gilane-Gharb (60.48%), Gazneh (52.44%), and Abdanan (47.43%), respectively. Although the altitude of Gazneh is different from that of Gilane-Gharb and Abdanan, all three regions had an average rainfall of 320-530 mm and a temperature of 15-30 degrees Celsius higher than the other studied regions. The lowest germination percentage was observed in the Kuzran (9%) and Najafabad (11.71%) populations, which had the lowest average rainfall (160-220 mm) and average temperature (10-15°C). The populations of Kamyaran, Zafarabad, and Ivan did not differ significantly from each other. This is despite the fact that the altitude of Kamyaran and Ivan regions is close to each other, but Zafarabad is higher. These regions were also similar in terms of temperature and rainfall during the growing season. The highest germination rate was related to treatments of three minutes at 80 and immediately at 4 degrees Celsius for 72 hours in Gazneh from Kurdistan (20.23) and the lowest germination rate was achieved in the Najafabad seed population. There was significant difference in germination index among stratification treatments. The highest germination index was for Gazneh (9.38) and the lowest was for control treatment of Najafabad and Silvaneh (0). The highest means germination time was check of Silvaneh (non-treated) (12.86) and the lowest rate was related to treatments of three minutes at 80 and immediately at 4°C for 72 hours in Silvaneh (0.03) and control treatment in Njafabad (0.04).<br /><strong>Conclusion. </strong>Appropriate timing is necessary to control this weed without chemical methods. Chilling generally increased the germination of this species; therefore, the appropriate timing for controlling this plant species is early spring because natural chilling occurs in the fall and winter, and germination will occur in the spring with moisture. By stimulating seed germination using weed control methods, newly germinated <br /><em>G. tricornutum</em> seeds can be removed from the field before they compete with the crop using low-cost methods such as shallow plowing. The success rate of this timing varies due to the different sensitivity of seeds in each region to chilling, but it will have a positive effect in all regions studied. Research on this species are usually time-consuming due to seed dormancy, and researchers may not be very interested in studying this species for this reason. Therefore, a low-cost method that can break seed dormancy in a short period of time would be of great help to researchers. https://ijfcs.ut.ac.ir/article_105084_722c8a74ffc3586f1e4d66ff2a48aebd.pdfUnivrsity of Tehran PressIranian Journal of Field Crop Science2008-481156420251222Growth and Yield Response of Guar (Cyamopsis tetragonoloba L.) to Nitrogen Application Rate Under Sulfur and No-Sulfur ApplicationGrowth and Yield Response of Guar (Cyamopsis tetragonoloba L.) to Nitrogen Application Rate Under Sulfur and No-Sulfur Application13314610509110.22059/ijfcs.2025.396020.655143FASaharKiani-MotlaghAgronomy Department , Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran.Seyed FarhadSaberAliAgronomy department, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran.MajidAghaAlikhaniAgronomy Department, Faculty of Agriculture, Tarbiat Modares University, Tehran, IranJournal Article20250526 <br /><br /><br /><br /><br /><strong>Introduction. </strong>Guar (<em>Cyamopsis tetragonoloba</em> L.) is well-suited for cultivation in tropical and subtropical regions with arid and semi-arid climates due to its high tolerance to drought and warm temperatures. Its significant industrial value and rising global demand have increased interest in its cultivation beyond traditional regions like India and Pakistan, including countries such as Iran. Following drought stress, nutrient deficiencies—particularly nitrogen—are major limiting factors for crop production, including guar. Nitrogen is an essential nutrient for plant growth, enhancing photosynthetic efficiency and playing critical roles in processes such as vegetative growth, leaf area expansion, and biomass accumulation. Under drought conditions and in soils with low populations of symbiotic rhizobia, nitrogen deficiency can severely limit guar production. Sulfur is another vital nutrient required for the synthesis of amino acids such as cystine, cysteine, and methionine, and is involved in the function of vitamins (e.g., biotin and thiamine), enzymes, lipids, and other essential plant components. sSulfur deficiency is particularly common in sandy soils with low organic matter.<br /><strong>Materials and Methods. </strong>This study was conducted in 2024 at the research farm of the Faculty of Agriculture, Tarbiat Modares University, located 17 km west of Tehran (35°44'N, 51°9'E; 1275 m above sea level). During the guar growing season, the average temperature was 28.73°C, and total rainfall was 1.6 mm. The experiment followed a factorial arrangement in a randomized complete block design (RCBD) with three replications. Treatments included two sulfur levels (0 and 100 kgha<sup>-1</sup>, from a bentonite sulfur source with 90% purity) and four nitrogen levels (0, 50, 100, and 150 kgha<sup>-1</sup>, applied as urea). Measured traits included biomass, leaf area, number of seeds per plant and pod, thousand-seed weight, harvest index, and seed yield per hectare. Leaf area and biomass were assessed during the vegetative stage through destructive sampling of 50 cm rfow lengths. Final yield components were measured by harvesting 1 m² plots at maturity.<br /><strong>Results and Discussion. </strong>Analysis of variance revealed that nitrogen application, unlike sulfur, had significant effects on leaf area index, dry matter accumulation, pod and seed numbers per unit area, grain yield, and harvest index. Nitrogen application increased grain yield by 21.2% compared to the control. Yield improvements at 50, 100, and 150 kg N ha<sup>-1</sup> were 12.8%, 33.8%, and 16.9%, respectively. Regression analysis indicated a significant quadratic response of grain yield to nitrogen application, explaining approximately 84% of the yield variation. The maximum increase in pod and seed numbers occurred at 100 kg ha<sup>-1</sup>, while no significant improvement was observed at 150 kg N ha<sup>-1</sup>, suggesting an optimal nitrogen level. Due to the strong influence of the number of grains formed per plant on grain weight, the increase in grain number in response to nitrogen application resulted in the allocation of dry matter among a larger number of grains, and therefore, changes in grain weight were not significant. Grain yield were attributed to enhanced leaf area index, biomass accumulation, and reproductive organ development. Previous studies support these findings, showing that nitrogen improves light interception, chlorophyll content, enzyme activity, and photosynthetic capacity. At 150 kg N ha<sup>-1</sup>, despite increased biomass, grain yield declined compared to 100 kg N ha<sup>-1</sup>, likely due to intra-plant competition and excessive vegetative growth at the expense of reproductive development. This was reflected in a reduced harvest index at the highest nitrogen level. The absence of significant yield or growth response to sulfur application may be attributed to adequate pre-existing soil sulfur levels (18 mg kg<sup>-1</sup>), suggesting that sulfur was not limiting.<br /><br /><br /><br /><br /><strong>Conclusion. </strong>Optimizing nitrogen application, considering local soil and climatic conditions, is a viable strategy for enhancing nitrogen use efficiency, improving yield, and reducing the environmental impact of excessive nitrogen fertilization in guar cultivation. <br /><br /><br /><br /><br /><strong>Introduction. </strong>Guar (<em>Cyamopsis tetragonoloba</em> L.) is well-suited for cultivation in tropical and subtropical regions with arid and semi-arid climates due to its high tolerance to drought and warm temperatures. Its significant industrial value and rising global demand have increased interest in its cultivation beyond traditional regions like India and Pakistan, including countries such as Iran. Following drought stress, nutrient deficiencies—particularly nitrogen—are major limiting factors for crop production, including guar. Nitrogen is an essential nutrient for plant growth, enhancing photosynthetic efficiency and playing critical roles in processes such as vegetative growth, leaf area expansion, and biomass accumulation. Under drought conditions and in soils with low populations of symbiotic rhizobia, nitrogen deficiency can severely limit guar production. Sulfur is another vital nutrient required for the synthesis of amino acids such as cystine, cysteine, and methionine, and is involved in the function of vitamins (e.g., biotin and thiamine), enzymes, lipids, and other essential plant components. sSulfur deficiency is particularly common in sandy soils with low organic matter.<br /><strong>Materials and Methods. </strong>This study was conducted in 2024 at the research farm of the Faculty of Agriculture, Tarbiat Modares University, located 17 km west of Tehran (35°44'N, 51°9'E; 1275 m above sea level). During the guar growing season, the average temperature was 28.73°C, and total rainfall was 1.6 mm. The experiment followed a factorial arrangement in a randomized complete block design (RCBD) with three replications. Treatments included two sulfur levels (0 and 100 kgha<sup>-1</sup>, from a bentonite sulfur source with 90% purity) and four nitrogen levels (0, 50, 100, and 150 kgha<sup>-1</sup>, applied as urea). Measured traits included biomass, leaf area, number of seeds per plant and pod, thousand-seed weight, harvest index, and seed yield per hectare. Leaf area and biomass were assessed during the vegetative stage through destructive sampling of 50 cm rfow lengths. Final yield components were measured by harvesting 1 m² plots at maturity.<br /><strong>Results and Discussion. </strong>Analysis of variance revealed that nitrogen application, unlike sulfur, had significant effects on leaf area index, dry matter accumulation, pod and seed numbers per unit area, grain yield, and harvest index. Nitrogen application increased grain yield by 21.2% compared to the control. Yield improvements at 50, 100, and 150 kg N ha<sup>-1</sup> were 12.8%, 33.8%, and 16.9%, respectively. Regression analysis indicated a significant quadratic response of grain yield to nitrogen application, explaining approximately 84% of the yield variation. The maximum increase in pod and seed numbers occurred at 100 kg ha<sup>-1</sup>, while no significant improvement was observed at 150 kg N ha<sup>-1</sup>, suggesting an optimal nitrogen level. Due to the strong influence of the number of grains formed per plant on grain weight, the increase in grain number in response to nitrogen application resulted in the allocation of dry matter among a larger number of grains, and therefore, changes in grain weight were not significant. Grain yield were attributed to enhanced leaf area index, biomass accumulation, and reproductive organ development. Previous studies support these findings, showing that nitrogen improves light interception, chlorophyll content, enzyme activity, and photosynthetic capacity. At 150 kg N ha<sup>-1</sup>, despite increased biomass, grain yield declined compared to 100 kg N ha<sup>-1</sup>, likely due to intra-plant competition and excessive vegetative growth at the expense of reproductive development. This was reflected in a reduced harvest index at the highest nitrogen level. The absence of significant yield or growth response to sulfur application may be attributed to adequate pre-existing soil sulfur levels (18 mg kg<sup>-1</sup>), suggesting that sulfur was not limiting.<br /><br /><br /><br /><br /><strong>Conclusion. </strong>Optimizing nitrogen application, considering local soil and climatic conditions, is a viable strategy for enhancing nitrogen use efficiency, improving yield, and reducing the environmental impact of excessive nitrogen fertilization in guar cultivation.https://ijfcs.ut.ac.ir/article_105091_b5d8a35a4533ef9bd30c68200b927d6c.pdfUnivrsity of Tehran PressIranian Journal of Field Crop Science2008-481156420251222Pysiological and photosynthetic responses of rice (Oryza sativa L.) subsp. indica and japonica to cold stressPysiological and photosynthetic responses of rice (Oryza sativa L.) subsp. indica and japonica to cold stress14716210573810.22059/ijfcs.2025.405517.655167FAEshaghi-GorjiFaridCollege of Agriculture and Natural Resources, University of Tehran, Karaj, IranRezaMaali-AmiriCollege of Agriculture and Natural Resources, University of Tehran, Karaj, IranMohammadrezaGhaffariAgriculture Biotechnology Research Institute of IranJournal Article20251104Rice (Oryza sativa L.) as a strategic cereal makes an important contribution to ensuring food security in Iran and the world. However, its production is severely affected by abiotic stresses, including cold. This study aimed to investigate the physiological and photosynthetic responses of four cultivars of rice from the indica subspecies, including "Shiroodi" and "Hashemi" , "Kohsar" (cold-tolerant), and a japonica subspecies, including "Gerde", during cold stress of 4 °C in the growth chamber of the Faculty of Agriculture, University of Tehran in 2023 based on a factorial experiment in a completely randomized design with three replications.. Cold stress significantly increased hydrogen peroxide (H2O2) in cultivars, while its level was reduced considerably in the cultivars Gerde and Kohsar compared to Shiroodi and Hashemi, which was related to higher antioxidant capacity of the cultivars Gerde and Kohsar. The content of chlorophyll a, b, and total chlorophyll decreased significantly by 81%, 73% and 78% respectively in response to cold stress, while the decrease was less in the tolerant cultivars (Gerde and Kohsar). In contrast, carotenoids accumulation as part of the defense response significantly increased by 46%. Chlorophyll fluorescence indices showed a significant decrease up to 73%, indicating damage to photosystem II, but in the cultivars Gerde and Kohsar, decreases were less. The results indicate a direct relationship between the reduction of cellular damage, preservation of photosynthetic pigments, and stability of photosystem II in improving cold tolerance in rice, which indicates that modulating oxidative stress and cell damage increases photosynthesis and plant survival.Rice (Oryza sativa L.) as a strategic cereal makes an important contribution to ensuring food security in Iran and the world. However, its production is severely affected by abiotic stresses, including cold. This study aimed to investigate the physiological and photosynthetic responses of four cultivars of rice from the indica subspecies, including "Shiroodi" and "Hashemi" , "Kohsar" (cold-tolerant), and a japonica subspecies, including "Gerde", during cold stress of 4 °C in the growth chamber of the Faculty of Agriculture, University of Tehran in 2023 based on a factorial experiment in a completely randomized design with three replications.. Cold stress significantly increased hydrogen peroxide (H2O2) in cultivars, while its level was reduced considerably in the cultivars Gerde and Kohsar compared to Shiroodi and Hashemi, which was related to higher antioxidant capacity of the cultivars Gerde and Kohsar. The content of chlorophyll a, b, and total chlorophyll decreased significantly by 81%, 73% and 78% respectively in response to cold stress, while the decrease was less in the tolerant cultivars (Gerde and Kohsar). In contrast, carotenoids accumulation as part of the defense response significantly increased by 46%. Chlorophyll fluorescence indices showed a significant decrease up to 73%, indicating damage to photosystem II, but in the cultivars Gerde and Kohsar, decreases were less. The results indicate a direct relationship between the reduction of cellular damage, preservation of photosynthetic pigments, and stability of photosystem II in improving cold tolerance in rice, which indicates that modulating oxidative stress and cell damage increases photosynthesis and plant survival.https://ijfcs.ut.ac.ir/article_105738_ca33411cec6dcfe0dad861cfecdfda81.pdf