Root Architectural Diversity in Wheat Cultivars and Its Role in Response to Terminal Water Stress

Document Type : Original Research

Authors
Afshin Zamani
Yahya Emam
Aref Nowrouzi
Department of Plant Production and Genetics, School of Agriculture, Shiraz University, Shiraz, Islamic Republic of Iran.
10.48311/jast.2026.24099
Abstract
Root architecture plays a key role in optimizing water uptake and sustaining yield under drought stress. The aim of this study was to investigate the role of vertical root distribution in determining the performance of three irrigated wheat cultivars under Terminal Water Stress (TWS). A field experiment was conducted during the 2021–2022 growing season at Shiraz University, evaluating three bread wheat cultivars: Pishgam, Torabi, and Sirvan. The low-cost "pasta strainer" method was adapted and employed to assess wheat mature root architecture in this context. To assess vertical root distribution, roots protruding through the side perforations of strainers were counted at three defined depth intervals: Shallow (2–8 cm; SRN), middle (8–10 cm; MRN), and deep (10–13 cm; DRN). The results revealed significant differences in root architecture among cultivars. Compared to Sirvan and Torabi, Pishgam exhibited a more uniform root distribution across SRN, MRN, and particularly DRN. A significant interaction between irrigation and cultivar was observed for root weight, root volume, shoot biomass, and Grain Yield (GY). Pishgam appeared to be superior in most of the measured traits. GY showed a positive association with MRN and DRN, which was further supported by principal component analysis aligning GY with root weight, root volume, MRN, and DRN. Despite the advantages and limitations of the pasta strainer method, our results demonstrated that cultivar with deeper rooting type, exhibited better drought performance.
Keywords
Mature root
Pasta strainer
Root phenotyping
Triticum aestivum L
Vertical root distribution
Subjects
1.       Alahmad, S., El Hassouni, K., Bassi, F. M., Dinglasan, E., Youssef, C., Quarry, G., Aksoy, A., Mazzucotelli, E., Juhász, A., Able, J. A., Christopher, J., Voss-Fels, K. P. and Hickey, L. T. 2019. A Major Root Architecture QTL Responding to Water Limitation in Durum Wheat. Front. Plant Sci., 10: 1–18.
2.       Amini, A., Majidi, M. M., Mokhtari, N.and Ghanavati, M. 2023. Drought Stress Memory in a Germplasm of Synthetic and Common Wheat: Antioxidant System, Physiological and Morphological Consequences. Sci. Rep., 13(1): 8569.
3.       Arzani, A.and Ashraf, M. 2017. Cultivated Ancient Wheats (Triticum spp.): A Potential Source of Health-Beneficial Food Products. Compr. Rev. Food Sci. Food Saf., 16(3): 477–488.
4.       Asefa, M., Worthy, S. J., Cao, M., Song, X., Lozano, Y. M.and Yang, J. 2022. Above- and Below-Ground Plant Traits Are not Consistent in Response to Drought and Competition Treatments. Ann. Bot., 130(7): 939–950.
5.       Awad, W., Byrne, P. F., Reid, S. D., Comas, L. H.and Haley, S. D. 2018. Great Plains Winter Wheat Varies for Root Length and Diameter under Drought Stress. Agron. J., 110(1): 226–235.
6.       Bakhtiar, F., Najafian, G., Khodarahmi, M., Ahmadi, G. H., Jafar-Nejad, A., Sarikhani Khorami, S., Amin Azarm, D., Ghandi, A., Nabati, E., Zareh Faiz Abadi, A., Nikzad, A., Abdi, H., Afshari, F., Zakeri, A., Yasaei, M., Ata Hoseini, S. M., Tabatabai, N., Dalvand, M., Ebrahim Nejad, S. … Tabatabaei, S. A. 2021. Torabi, New Wheat Cultivar Suitable for Water-Stressed Conditions of Temperate Regions of Iran. Res. Achv. Field Hortic. Crops, 9(2): 101–113.
7.       Basirat, M., Mousavi, S. M., Abbaszadeh, S., Ebrahimi, M.and Zarebanadkouki, M. 2019. The Rhizosheath: A Potential Root Trait Helping Plants to Tolerate Drought Stress. Plant Soil, 445(1): 565–575.
8.       Borrell, A. K., Mullet, J. E., George-Jaeggli, B., van Oosterom, E. J., Hammer, G. L., Klein, P. E. and Jordan, D. R. 2014. Drought Adaptation of Stay-Green Sorghum Is Associated with Canopy Development, Leaf Anatomy, Root Growth, and Water Uptake. J. Exp. Bot., 65(21): 6251–6263.
9.       Botwright Acuña, T. L. and Wade, L. J. 2012. Genotype×Environment Interactions for Root Depth of Wheat. Field Crops Res., 137: 117–125.
10.    Boudiar, R., Cabeza, A., Fernández-Calleja, M., Pérez-Torres, A., Casas, A. M., González, J. M., Mekhlouf, A. and Igartua, E. 2021. Root Trait Diversity in Field Grown Durum Wheat and Comparison with Seedlings. Agron., 11(12): 2545.
11.    Chen, Y., Palta, J., Prasad, P. V. V. and Siddique, K. H. M. 2020. Phenotypic Variability in Bread Wheat Root Systems at the Early Vegetative Stage. BMC Plant Biol., 20(1): 185.
12.    Crocker, T. L., Hendrick, R. L., Ruess, R. W., Pregitzer, K. S., Burton, A. J., Allen, M. F., Shan, J. and Morris, L. A. 2003. Substituting Root Numbers for Length: Improving the Use of Minirhizotrons to Study Fine Root Dynamics. Appl. Soil Ecol., 23(2): 127–135.
13.    Deery, D. M., Rebetzke, G. J., Jimenez-Berni, J. A., Bovill, W. D., James, R. A., Condon, A. G., Furbank, R. T., Chapman, S. C. and Fischer, R. A. 2019. Evaluation of the Phenotypic Repeatability of Canopy Temperature in Wheat Using Continuous-Terrestrial and Airborne Measurements. Front. Plant Sci., 10: 875.
14.    Ehdaie, B., Layne, A. P. and Waines, J. G. 2012. Root System Plasticity to Drought Influences Grain Yield in Bread Wheat. Euphytica, 186(1): 219–232.
15.    El Hassouni, K., Alahmad, S., Belkadi, B., Filali-Maltouf, A., Hickey, L. T. and Bassi, F. M. 2018. Root System Architecture and Its Association with Yield under Different Water Regimes in Durum Wheat. Crop Sci., 58(6): 2331–2346.
16.    FAOSTAT. 2024. Accessed at https://www.fao.org/faostat/en/#data/QCL
17.    Figueroa-bustos, V., Palta, J. A., Chen, Y., Stefanova, K., Siddique, K. H. M. and Armstrong, R. D. 2020. Wheat Cultivars with Contrasting Root System Size Responded Differently to Terminal Drought. Front. Plant Sci., 11: 1–12.
18.    Fradgley, N., Evans, G., Biernaskie, J. M., Cockram, J., Marr, E. C., Oliver, A. G., Ober, E. and Jones, H. 2020. Effects of Breeding History and Crop Management on the Root Architecture of Wheat. Plant Soil, 452(1): 587–600.
19.    Gioia, T., Galinski, A., Lenz, H., Müller, C., Lentz, J., Heinz, K., Briese, C., Putz, A., Fiorani, F., Watt, M., Schurr, U. and Nagel, K. A. 2017. GrowScreen-PaGe, a Non-Invasive, High-Throughput Phenotyping System Based on Germination Paper to Quantify Crop Phenotypic Diversity and Plasticity of Root Traits under Varying Nutrient Supply. Funct. Plant Biol., 44(1): 76–93.
20.    Gutierrez, M., Reynolds, M. P. and Klatt, A. R. 2010. Association of Water Spectral Indices with Plant and Soil Water Relations in Contrasting Wheat Genotypes. J. Exp. Bot., 61(12): 3291–3303.
21.    Haghpanah, M., Hashemipetroudi, S., Arzani, A. and Araniti, F. 2024. Drought Tolerance in Plants: Physiological and Molecular Responses. Plants, 13(21): 2962.
22.    Haghshenas, A., Emam, Y., Sepaskhah, A. R. and Edalat, M. 2021. Can Extended Phenology in Wheat Cultivar Mixtures Mitigate Post-Anthesis Water Stress? Eur. J. Agron., 122: 126188.
23.    Hosseini, S. S., Razavi, B. S. and Lakzian, A. 2024. Drought Tolerance of Wheat Genotypes Is Associated with Rhizosphere Size and Enzyme System. Plant Soil, 502(1): 671–685.
24.    Khodaee, S. M. M., Hashemi, M., Mirlohi, A., Majidi, M. M., Sukumaran, S., Esmaelzaeh Moghaddam, M. and Abdollahi, M. 2021. Root Characteristics of an Elite Spring Wheat Panel under Contrasting Water Treatments and Their Genome-Wide Association Study. Rhizosphere, 19: 100413.
25.    Li, C., Li, L., Reynolds, M. P., Wang, J., Chang, X., Mao, X. and Jing, R. 2021. Recognizing the Hidden Half in Wheat: Root System Attributes Associated with Drought Tolerance. J. Exp. Bot., 72(14): 5117–5133.
26.    Li, X., Ingvordsen, C. H., Weiss, M., Rebetzke, G. J., Condon, A. G., James, R. A. and Richards, R. A. 2019. Deeper Roots Associated with Cooler Canopies, Higher Normalized Difference Vegetation Index, and Greater Yield in Three Wheat Populations Grown on Stored Soil Water. J. Exp. Bot., 70(18): 4963–4974.
27.    Maccaferri, M., El-Feki, W., Nazemi, G., Salvi, S., Canè, M. A., Colalongo, M. C., Stefanelli, S. and Tuberosa, R. 2016. Prioritizing Quantitative Trait Loci for Root System Architecture in Tetraploid Wheat. J. Exp. Bot., 67(4): 1161–1178.
28.    Mahdavi, Z., Rashidi, V., Yarnia, M., Aharizad, S. and Roustaii, M. 2023. Evaluation of Yield Traits and Tolerance Indices of Different Wheat Genotypes under Drought Stress Conditions. Cereal Res. Commun., 51(3): 659–669.
29.    Mahfoozi, S., Akbari, A., Chaichi, M., Sanjari, A. G., Nazeri, S. M., Abedi-Oskooee, S., Aminzadeh, G. and Rezaie, M. 2009. Pishgam, a New Bread Wheat Cultivar for Normal Irrigation and Terminal Stage Deficit Irrigation Conditions of Cold Regions of Iran. Seed Plant J., 25(3): 513–517.
30.    Manschadi, A. M., Christopher, J., deVoil, P. and Hammer, G. L. 2006. The Role of Root Architectural Traits in Adaptation of Wheat to Water-Limited Environments. Funct. Plant Biol., 33(9): 823–837.
31.    Manschadi, A. M., Hammer, G. L., Christopher, J. T. and deVoil, P. 2008. Genotypic Variation in Seedling Root Architectural Traits and Implications for Drought Adaptation in Wheat (Triticum aestivum L.). Plant Soil, 303(1): 115–129.
32.    Mehrabi, F., Sepaskhah, A. R. and Ahmadi, S. H. 2021. Winter Wheat Root Distribution with Irrigation, Olanting Methods, and Nitrogen Application. Nutr. Cycl. Agroecosyst., 119(2): 231–245.
33.    Mohammadi, M., Mirlohi, A., Majidi, M. M. and Rabbani, A. 2021. Exploring the Breeding Potential of Iranian Emmer Wheats to Increase Durum Wheat Tolerance to Drought. Plant Genet. Resour. Charact. Util., 19(4): 363–374.
34.    Mohammadi, R. 2024. Effects of Post-Flowering Drought and Supplemental Irrigation on Grain Yield and Agro-Phenological Traits in Durum Wheat. Eur. J. Agron., 156: 127180.
35.    Mokhtari, N., Majidi, M. M. and Mirlohi, A. 2024. Physiological and Antioxidant Responses of Synthetic Hexaploid Wheat Germplasm under Drought. BMC Plant Biol., 24(1): 747.
36.    Mokhtari, N., Majidi, M. M. and Mirlohi, A. 2025. Synthetic Wheat as a New Source of Flour Quality under Drought Conditions: Associations with Solvent Retention Capacity. PLoS One, 20(2): e0316945.
37.    Nagel, K. A., Lenz, H., Kastenholz, B., Gilmer, F., Averesch, A., Putz, A., Heinz, K., Fischbach, A., Scharr, H., Fiorani, F., Walter, A. and Schurr, U. 2020. The Platform GrowScreen-Agar Enables Identification of Phenotypic Diversity in Root and Shoot Growth Traits of Agar Grown Plants. Plant Methods, 16(1): 89.
38.    Najafi, M. S. and Alizadeh, O. 2023. Climate Zones in Iran. Meteorol. Appl., 30(5): e2147.
39.    Najafian, G., Khodarahmi, M., Amini, A., Afshari, F., Malihipour, A., Ahmadi, Gh. H., Nikooseresht, R., Kafashi, A. K., Amin, H., Zakari, A., Nikzad, A. R., Jafarnezhad, A., Afuni, D., Hassanpour, J., Mohammadi, A. R., Atahossaini, S. M., Nazeri, A., Mirzaie, A. allah, Shourabi, A. A., Shad Mehri, A., Badri, A. R., Momen, A. and Sadeghi, N. 2012. Sirvan, New Bread Wheat Cultivar, Tolerant to Terminal Frought with Good Bread Making Quality Adapted to Irrigate Conditions of Temperate Regions of Iran. Res. Achv. Field Hortic. Crops, 1(1): 1–10.
40.    Nakhforoosh, A., Nagel, K. A., Fiorani, F. and Bodner, G. 2021. Deep Soil Exploration vs. Topsoil Exploitation: Distinctive Rooting Strategies between Wheat Landraces and Wild Relatives. Plant Soil, 459(1): 397–421.
41.    Ober, E. S., Alahmad, S., Cockram, J., Forestan, C., Hickey, L. T., Kant, J., Maccaferri, M., Marr, E., Milner, M., Pinto, F., Rambla, C., Reynolds, M., Salvi, S., Sciara, G., Snowdon, R. J., Thomelin, P., Tuberosa, R., Uauy, C., Voss-Fels, K. P., Wallington, E. and Watt, M. 2021. Wheat Root Systems as a Breeding Target for Climate Resilience. Theor. Appl. Genet., 134(6): 1645–1662.
42.    Palta, J. A., Chen, X., Milroy, S. P., Rebetzke, G. J., Dreccer, M. F. and Watt, M. 2011. Large Root Systems: Are They Useful in Adapting Wheat to Dry Environments? Funct.Plant Biol., 38(5): 347–354.
43.    Pinto, R. S. and Reynolds, M. P. 2015. Common Genetic Basis for Canopy Temperature Depression under Heat and Drought Stress Associated with Optimized Root Distribution in Bread Wheat. Theor. Appl. Genet., 128(4): 575–585.
44.    Pirnajmedin, F., Majidi, M. and Gheysari, M. 2015. Root and Physiological Characteristics Associated with Drought Tolerance in Iranian Tall Fescue. Euphytica, 202(1): 141–155.
45.    Pirnajmedin, F., Majidi, M. and Jaškūnė, K. 2024. Adaptive Strategies to Drought Stress in Grasses of the Poaceae Family under Climate Change: Physiological, Genetic and Molecular Perspectives: A review. Plant Physiol. Biochem., 213: 108814.
46.    Pirnajmedin, F., Majidi, M. M. and Gheysari, M. 2016. Survival and Recovery of Tall Fescue Genotypes: Association with Root Characteristics and Drought Tolerance. Grass and Forage Sci., 71(4): 632–640.
47.    Raherison, E., Majidi, M. M., Goessen, R., Hughes, N., Cuthbert, R., Knox, R. and Lukens, L. 2020. Evidence for the Accumulation of Nonsynonymous Mutations and Favorable Pleiotropic Alleles During Wheat Breeding. G3 Gene Genome. Genet., 10(11): 4001–4011.
48.    Ranjan, A., Sinha, R., Singla-Pareek, S. L., Pareek, A. and Singh, A. K. 2022. Shaping the Root System Architecture in Plants for Adaptation to Drought Stress. Physiol. Plant., 174(2): e13651.
49.    Richard, C., Hickey, L. T., Fletcher, S., Jennings, R., Chenu, K. and Christopher, J. T. 2015. High-Throughput Phenotyping of Seminal Root Traits in Wheat. Plant Methods, 11(1): 1–11.
50.    Robinson, H., Kelly, A., Fox, G., Franckowiak, J., Borrell, A. and Hickey, L. 2018. Root Architectural Traits and Yield: Exploring the Relationship in Barley Breeding Trials. Euphytica, 214(9): 151.
51.    Senapati, N., Stratonovitch, P., Paul, M. J. and Semenov, M. A. 2019. Drought Tolerance during Reproductive Development Is Important for Increasing Wheat Yield Potential under Climate Change in Europe. J. Exp. Bot., 70(9): 2549–2560.
52.    Severini, A. D., Wasson, A. P., Evans, J. R., Richards, R. A. and Watt, M. 2020. Root Phenotypes at Maturity in Diverse Wheat and Triticale Genotypes Grown in Three Field Experiments: Relationships to Shoot Selection, Biomass, Grain Yield, Flowering Time, and Environment. Field Crops Res., 255: 107870.
53.    Shazadi, K., Christopher, J. T. and Chenu, K. 2024. Does Late Water Deficit Induce Root Growth or Senescence in Wheat? Front. Plant Sci., 15: 1–14.
54.    Tang, D., Chen, M., Huang, X., Zhang, G., Zeng, L., Zhang, G., Wu, S. and Wang, Y. 2023. SRplot: A Free Online Platform for Data Visualization and Graphing. PLoS ONE, 18(11): 1-8.
55.    Turner, N. C. and Nicolas, M. E. 1987. Drought Resistance of Wheat for Light-Textured Soils in the Mediterranean Climate. In: "Drought Tolerance in Winter Cereals", (Eds.): Srivastava, J. P., Porceddu, E. Acevedo, E. and Varma, S. John Wiley & Sons, Ltd., PP. 203–216.
56.    Uga, Y., Ebana, K., Abe, J., Morita, S., Okuno, K. and Yano, M. 2009. Variation in Root Morphology and Anatomy among Accessions of Cultivated Rice (Oryza sativa L.) with Different Genetic Backgrounds. Breed. Sci., 59(1): 87–93.
57.    Vadez, V. 2014. Root Hydraulics: The Forgotten Side of Roots in Drought Adaptation. Field Crops Res., 165: 15–24.
58.    Wasson, A., Bischof, L., Zwart, A. and Watt, M. 2016. A Portable Fluorescence Spectroscopy Imaging System for Automated Root Phenotyping in Soil Cores in the Field. J. Exp. Bot., 67(4): 1033–1043.
59.    Wasson, A. P., Richards, R. A., Chatrath, R., Misra, S. C., Prasad, S. V. S., Rebetzke, G. J., Kirkegaard, J. A., Christopher, J. and Watt, M. 2012. Traits and Selection Strategies to Improve Root Systems and Water Uptake in Water-Limited Wheat Crops. J. Exp. Bot., 63(9): 3485–3498.
60.    Xie, Q., Mayes, S. and Sparkes, D. L. 2015. Carpel Size, Grain Filling, and Morphology Determine Individual Grain Weight in Wheat. J. Exp. Bot., 66(21): 6715–6730.
61.    Zadoks, J. C., Chang, T. T. and Konzak, C. F. 1974. A Decimal Code for the Growth Stages of Cereals. Weed Res., 14(6): 415–421.
62.    Zamani, A., Emam, Y. and Edalat, M. 2024. Response of Bread Wheat Cultivars to Terminal Water Stress and Cytokinin Application from a Grain Phenotyping Perspective. Agronomy, 14(1): 182.
63.    Zampieri, M., Ceglar, A., Dentener, F. and Toreti, A. 2017. Wheat Yield Loss Attributable to Heat Waves, Drought and Water Excess at the Global, National and Subnational Scales. Environ. Res. Lett., 12(6): 64008. 
Journal of Agricultural Science and Technology
Volume 28, Issue 3
May and June 2026
Pages 715-730