Document Type : Research Paper
Authors
1 genetics and plant breeding, Department of Agronomy and Plant Breeding sciences, Aburaihan Faculty of Agricultural Technology, University of Tehran, Pakdasht, Tehran, Iran
2 Department of Agronomy and Plant Breeding Sciences, Aburaihan Faculty of Agricultural Technology, University of Tehran, Pakdasht, Tehran, Iran
3 Department of Plant Genetics and Breeding, Faculty of Agricultural Technology, University of Tehran, Pakdasht, Iran.
4 Department of Plant Genetics and Breeding, Faculty of Agricultural Technology, University of Tehran, Pakdasht, Iran
Abstract
Abstract
Objective:
This study was conducted to evaluate the forage quality of Festuca pratensis genotypes under water deficit stress. The experiment was carried out over three consecutive years (2022–2024) at the Research Farm of the Faculty of Agricultural Technology, University of Tehran, with the goal of identifying drought-tolerant genotypes that also maintain high nutritional value.
Materials and Methods:
Seeds of 20 genotypes of Festuca pratensis were obtained from the NordGen gene bank in Sweden and the ART Institute in Switzerland. The experiment was established in a split-plot design in time using a randomized complete block design (RCBD) with three replications. The genotypes were evaluated under two irrigation regimes: normal (100 percent field capacity) and water deficit (50 percent field capacity), following the full establishment of the plants. Sampling was conducted at the mid-flowering stage after two consecutive years of stress application, in May 2023 and May 2024. Several key forage quality traits were measured, including acid detergent fiber (ADF), neutral detergent fiber (NDF), cellulose, lignin, nitrogen content, ash, dry matter intake (DMI), in vitro dry matter digestibility (IVDMD), metabolizable energy (ME), and relative feed value (RFV).
Results:
The analysis of variance revealed that drought stress significantly affected all studied traits at the one percent probability level. Significant effects were also observed for genotype and harvest, as well as for the two-way interactions of stress × genotype and genotype × harvest, and the three-way interaction of stress × genotype × harvest for all traits except cellulose. Additionally, the interaction between stress and harvest was significant for all traits except ash. Based on the results of mean comparisons, genotypes 2, 13, 14, 15, 16, and 17 showed superior performance under drought stress, exhibiting higher crude protein and lower ADF and NDF values, which indicate better forage quality.
Conclusion:
This study confirms that forage quality evaluation under water-limited conditions is an effective approach to identifying high-value, drought-tolerant genotypes. The promising performance of selected genotypes suggests that Festuca pratensis has strong potential for development in arid and semi-arid regions. These findings provide a valuable foundation for future breeding programs aimed at producing drought-resilient cultivars while maintaining forage quality. Furthermore, integrating forage quality indicators with drought tolerance traits could enhance the precision and efficiency of genotype selection in breeding programs. Long-term and multi-location trials are recommended to verify the adaptability and stability of the identified genotypes under diverse environmental conditions. The results may inform water resource management strategies in forage production systems under similar climatic conditions.
Keywords
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