University of Tabriz Journal of Agricultural Science and Sustainable Production 2476-4310 35 1 2025 04 30 Effect of Foliar Application of Seaweed Extract on Growth, Yield and Quality of Forage Sorghum (Sorghum bicolor L. Moench) Effect of Foliar Application of Seaweed Extract on Growth, Yield and Quality of Forage Sorghum (Sorghum bicolor L. Moench) 83 96 19792 10.22034/saps.2023.54399.2958 FA Mohammad Reza Bahiraei Department of Crop Production and , Faculty of Agriculture, Bu-Ali Sina University Javad Hamzei Dept. of Plant Production and Genetics, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran. Mohammad Ali Abotalebian Dept. of Plant Production and Genetics, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran. Journal Article 2022 12 11 <strong>Backgraound and Objective:</strong> Seaweed extracts serve as natural bio-stimulants, enhancing plant growth and productivity due to their rich composition of nutrients and bioactive compounds. Optimizing growth, yield, and quality in forage sorghum (Sorghum bicolor L. Moench) is crucial for improving livestock nutrition and sustainable fodder production. However, studies on foliar application of seaweed extract in sorghum, particularly in the speedfeed cultivar, remain limited. This study aimed to assess the effects of different concentrations of seaweed extract on sorghum growth indices, yield, and fodder quality to identify the optimal application rate for maximizing performance and resource efficiency.<br /><strong> </strong><br /><strong>Matherials and Methods:</strong> This experiment was conducted in a randomized complete blocks design with five treatments and three replications. Treatments included foliar application of water (control) and 0.5, 1, 1.5 and 2 L/ha of seaweed extract. Leaf area index, crop growth rate, net assimilation rate, fresh and dry fodder yield and fodder quality (digestibility, protein percentage, crude fiber percentage, and carbohydrate) were measured and evaluated.<br /><strong> </strong><br /><strong>Results: </strong>The effect of seaweed extract foliar application on leaf area index, crop growth rate, net absorption rate and quantitative and qualitative yield of sorghum was significant. There was no significant difference between the concentrations of 1.5 and 2 L/ha of seaweed extract in most of the investigated traits. So that the highest amount of growth indices, total dry yield, protein percentage and the lowest amount of crude fiber were obtained from the application of 1.5 L/ha of seaweed extract. The lowest amount of these characteristics and the highest amount of crude fiber were obtained from the control treatment.<br /><strong> </strong><br /><strong>Conclusion: </strong>Overall, the application of seaweed extract improved the growth of sorghum fodder. The optimal treatment (1.5 L/ha of seaweed extract) boosted the leaf area index, crop growth rate, and total yield of sorghum by 32%, 26.71%, and 20.56% respectively compared to the control treatment, making it the most effective option.<br />  <strong>Backgraound and Objective:</strong> Seaweed extracts serve as natural bio-stimulants, enhancing plant growth and productivity due to their rich composition of nutrients and bioactive compounds. Optimizing growth, yield, and quality in forage sorghum (Sorghum bicolor L. Moench) is crucial for improving livestock nutrition and sustainable fodder production. However, studies on foliar application of seaweed extract in sorghum, particularly in the speedfeed cultivar, remain limited. This study aimed to assess the effects of different concentrations of seaweed extract on sorghum growth indices, yield, and fodder quality to identify the optimal application rate for maximizing performance and resource efficiency.<br /><strong> </strong><br /><strong>Matherials and Methods:</strong> This experiment was conducted in a randomized complete blocks design with five treatments and three replications. Treatments included foliar application of water (control) and 0.5, 1, 1.5 and 2 L/ha of seaweed extract. Leaf area index, crop growth rate, net assimilation rate, fresh and dry fodder yield and fodder quality (digestibility, protein percentage, crude fiber percentage, and carbohydrate) were measured and evaluated.<br /><strong> </strong><br /><strong>Results: </strong>The effect of seaweed extract foliar application on leaf area index, crop growth rate, net absorption rate and quantitative and qualitative yield of sorghum was significant. There was no significant difference between the concentrations of 1.5 and 2 L/ha of seaweed extract in most of the investigated traits. So that the highest amount of growth indices, total dry yield, protein percentage and the lowest amount of crude fiber were obtained from the application of 1.5 L/ha of seaweed extract. The lowest amount of these characteristics and the highest amount of crude fiber were obtained from the control treatment.<br /><strong> </strong><br /><strong>Conclusion: </strong>Overall, the application of seaweed extract improved the growth of sorghum fodder. The optimal treatment (1.5 L/ha of seaweed extract) boosted the leaf area index, crop growth rate, and total yield of sorghum by 32%, 26.71%, and 20.56% respectively compared to the control treatment, making it the most effective option.<br />  https://sustainagriculture.tabrizu.ac.ir/article_19792_7314d279df2456f040827e16db93656c.pdf