1
Ege University, Faculty of Agriculture, Department of Field Crops, Izmir
2
Ege University, Faculty of Agriculture, Department of Field Crops, Izmir
Abstract
Drought stress poses a significant challenge to global forage production, particularly under climate change conditions. Identifying cultivars with superior drought tolerance is essential for maintaining productivity in water-limited environments. The objective of the study was to evaluate the effects of polyethylene glycol (PEG)-induced drought stress on the germination and seedling growth traits of tetraploid annual ryegrass (Lolium multiflorum Lam.) cultivars. Four cultivars (Baqueano, Big Boss, Elif, and Medoacus) were exposed to seven osmotic potential levels (0, -0.2, -0.4, -0.6, -0.8, -1.0, and -1.2 MPa) under controlled conditions. Germination rate (%), mean germination time (day), shoot and root length (cm), shoot-to-root ratio, seedling fresh weight (mg), vigor index, and drought tolerance index (%) were determined. The results revealed significant reductions in germination and seedling growth traits with increasing drought stress. Among the cultivars, Baqueano and Big Boss cultivars exhibited superior drought tolerance, maintaining higher vigor and drought tolerance indices. An osmotic potential of -0.6 MPa reduced the drought tolerance index by up to 44.5%, with no germination observed at -1.2 MPa. Strong correlations were identified among germination rate, shoot and root length, vigor index, and drought tolerance index, highlighting their importance as indicators of drought resilience.
Keywords
Italian ryegrass,germination,drought,polyethylene glycol,thousand-seed weight,correlation
How to Cite
ÖZKAN, Şükrü S., & LEVENT, K. (2025). The Influence of PEG-Induced Drought Stress on Seed Germination and Seedling Growth Traits of Tetraploid Annual Ryegrass Cultivars. ISPEC Journal of Agricultural Sciences, 9(1), 177–189. https://doi.org/10.5281/zenodo.14601302
📄Aktar, Y., Polat, T., Okant, M., Kurt, I., 2021. Single annual forage Italian ryegrass (Lolium multiflorum L.) determination of some properties in the type of plant. ISPEC Journal of Agricultural Sciences, 5(1): 193-201.
📄Almaghrabi, O.A., 2012. Impact of drought stress on germination and seedling growth parameters of some wheat cultivars. Life Science Journal, 9(1): 590-598.
📄Anonymous, 2023. Crop and animal production statistics. Turkish Statistical Institute, Ankara.
📄Balkan, A., Genctan, T., 2013. Effect of osmatic stress on germination and early growth in bread wheat (Triticum aestivum). Journal of Tekirdag Agricultural Faculty, 10(2): 44-52.
📄Basu, S., Roychoudhury, A., Saha, P.P., Sengupta, D.N., 2010. Comparative analysis of some biochemical responses of three indica rice varieties during polyethylene glycol-mediated water stress exhibits distinct varietal differences. Acta Physiologiae Plantarum, 32: 551-563.
📄Benech-Arnold, R.L., Sánchez R.A., 2004. Handbook of seed physiology: applications to agriculture. CRC Press.
📄Berg, L., Zeng, Y.J., 2006. Response of South African indigenous grass species to drought stress induced by polyethylene glycol (PEG) 6000. South African Journal of Botany, 72(2): 284-286.
📄Bhattacharya, A., Vijaya, L., 2021. Methods and techniques in plant physiology. New India Publishing Agency (Nipa), India, 212p.
📄Bilgili, D., Mehmet, A., Kazim, M., 2019. Effects of PEG-induced drought stress on germination and seedling performance of bread wheat genotypes. Yuzuncu Yıl University Journal of Agricultural Science, 29(4): 765-771.
📄Billah, M., Aktar, S., Brestic, M., Zivcak, M., Khaldun, A.B.M., Uddin, M.S., Bagum, S.A., Yang, X., Skalicky, M., Mehari, T.G., Maitra, S., Hossain, A., 2021. Progressive genomic approaches to explore drought-and salt-induced oxidative stress responses in plants under changing climate. Plants, 10(9): 1910.
📄Borawska-Jarmulowicz, B., Mastalerczuk, G., Gozdowski, D., Maluszynska, E., Szydlowska, A., 2017. The sensitivity of Lolium perenne and Poa pratensis to salinity and drought during the seed germination and under different photoperiod conditions. Zemdirbyste-Agriculture, 104(1): 71-78.
📄Budakli Carpici, E., Erdel, B., 2015. Effects of drought stress on germination characters of some alfalfa (Medicago sativa L.) varieties. Derim, 32(2): 201-210.
📄Castroluna, A., Ruiz, O.M., Quiroga, A.M., Pedranzani, H.E., 2014. Effects of salinity and drought stress on germination, biomass and growth in three varieties of Medicago sativa L. Avances en Investigación Agropecuaria, 18(1): 39-50.
📄Comas, L.H., Becker, S.R., Cruz, V.M.V., Byrne, P.F., Dierig, D.A., 2013. Root traits contributing to plant productivity under drought. Frontiers in Plant Science, 4: 442.
📄Crawford, S.L., 2006. Correlation and regression. Circulation, 114(19): 2083-2088.
📄Demiroglu Topcu, G., Celen, A.E., Kuru, E., Ozkan, S.S., 2016. A study on the effects of different NaCl concentrations on germination and early growing stage of tall fescue (Festuca arundinacea) and intermediate wheatgrass (Agropyron intermedium). Journal of Central Research Institute for Field Crops, 25(Special Issue-2): 219-224.
📄Demiroglu Topcu, G., Celen, A.E., Ozkan, S.S., 2021. The effects of different harvest times on yield and some quality components of annual ryegrass (Lolium multiflorum Lam.) varieties. Fresenius Environmental Bulletin, 30(02A): 1810-1816.
📄Demiroglu Topcu, G., Ozkan, S.S., 2016. Effects of salt and drought stresses on germination and seedling growth of sainfoin (Onobrychis viciifolia Scop.). Journal of Agricultural Faculty of Uludag University, 30(Special Issue): 406-409.
📄Demiroglu Topcu, G., Ozkan, S.S., 2020. Effects of different salt sources and concentrations on germination parameters of barley (Hordeum vulgare L.) seeds. ISPEC Journal of Agricultural Sciences, 4(3): 456-467.
📄El-Kassaby, Y.A. Edwards, D.G.W., 2001. Germination ecology in mountain hemlock (Tsuga mertensiana (Bong.) Carr.). Forest Ecology and Management, 144(1-3): 183-188.
📄Ellis, R.H., Roberts, E.H., 1980. Towards a rational basis for testing seed quality. In: Seed Production (ed: P.D. Hebblethwaite), Butterworths, London, pp. 605-635.
📄Eser, V., Agiragac, Z., Zorer Celebi, S., 2024. Effects of organic fertilizers and mowing times on grass yield and feed value of Italian grass (Lolium multiflorum Lam.). ISPEC Journal of Agricultural Sciences, 8(3): 709-721.
📄Gašparovič, K., Živčák, M., Brestič, M., Hauptvogel, P., 2021. Diversity of leaf cuticular transpiration and growth traits in field-grown wheat and aegilops genetic resources. Agronomy, 11(3): 522.
📄Gholami, M., Rahemi, M., Kholdebarin, B., 2010. Effect of drought stress induced by polyethylene glycol on seed germination of four wild almond species. Australian Journal of Basic and Applied Sciences, 4(5): 785-791.
📄Hellal, F.A., El-Shabrawi, H.M., Abd El-Hady, M., Khatab, I.A., El-Sayed, S.A.A., Abdelly, C., 2018. Influence of PEG induced drought stress on molecular and biochemical constituents and seedling growth of Egyptian barley cultivars. Journal of Genetic Engineering and Biotechnology, 16(1): 203-212.
📄Hu, J., Zhu, Z.Y., Song, W.J., Wang, J.C., Hu, W.M., 2005. Effects of sand priming on germination and field performance in direct-sown rice (Oryza sativa L.). Seed Science and Technology, 33(1): 243-248.
📄Hussain, M., Farooq, S., Jabran, K., Ijaz, M., Sattar, A., Hassan, W., 2016. Wheat sown with narrow spacing results in higher yield and water use efficiency under deficit supplemental irrigation at the vegetative and reproductive stage. Agronomy, 6(2): 22.
📄Ibrahimova, U., Zivcak, M., Gasparovic, K., Rastogi, A., Allakhverdiev, S. I., Yang, X., Brestic, M., 2021. Electron and proton transport in wheat exposed to salt stress: is the increase of the thylakoid membrane proton conductivity responsible for decreasing the photosynthetic activity in sensitive genotypes?. Photosynthesis Research, 150(1): 195-211.
📄ISTA, 2018. International rules for seed testing book. International Seed Testing Association (ISTA) Press, Switzerland.
📄Johnson, R.A., Bhattacharyya, G.K., 2019. Statistics: principles and methods (8th edition). Wiley & Sons Inc.
📄Jorjandi, M., Sharifi-Sirchi, G.R., 2012. The effect of priming on germination and seedling growth of alfalfa (Medicago sativa L.) under salinity stress. Journal of Stress Physiology & Biochemistry, 8(3): 234-239.
📄Kalefetoglu Macar, T., Turan, O., Ekmekci, Y., 2009. Effect of water deficit induced by PEG and NaCl on chickpea (Cicer arietinum L.) cultivar and lines at early seedling stage. Gazi University Journal of Science, 22(1): 5-14.
📄Kaur, S., Gupta, A.K., Kaur, N., 2002. Effect of osmo-and hydropriming of chickpea seeds on seedling growth and carbohydrate metabolism under water deficit stress. Plant Growth Regulation, 37: 17-22.
📄Khayatnezhad, M., Gholamin, R., Jamaatie-Somarin, S.H., Zabihi-Mahmoodabad, R., 2010. Effects of PEG stress on corn cultivars (Zea mays L.) at germination stage. World Applied Sciences Journal, 11(5): 504-506.
📄Khodarahmpour, Z., 2011. Effect of drought stress induced by polyethylene glycol (PEG) on germination indices in corn (Zea mays L.) hybrids. African Journal of Biotechnology, 10(79): 18222-18227.
📄Khoyerdi, F.F., Shamshiri, M.H., Estaji, A., 2016. Changes in some physiological and osmotic parameters of several pistachio genotypes under drought stress. Scientia Horticulturae, 198: 44-51.
📄Lale, V., Kokten, K., 2020. Determination of herbage yield and quality of some Italian ryegrass (Lolium multiflorum Lam.) varieties in Bingol conditions. Turkish Journal of Nature and Science, 9(Special Issue): 46-50.
📄Larson, L., Kiemnec, G., 2005. Germination of two noxious range weeds under water and salt stresses with variable light regimes. Weed Technology, 19(1): 197-200.
📄Lee, K.W., Woo, J.H., Song, Y., Lee, S.H., Rahman, M.A., 2022. Drought tolerance in Italian ryegrass is associated with genetic divergence, water relation, photosynthetic efficiency and oxidative stress responses. Journal of the Korean Society of Grassland and Forage Science, 42(3): 208-214.
📄Li, Z., Peng, Y., Zhang, X.Q., Ma, X., Huang, L.K., Yan, Y.H., 2014. Exogenous spermidine improves seed germination of white clover under water stress via involvement in starch metabolism, antioxidant defenses and relevant gene expression. Molecules, 19(11): 18003-18024.
📄Lipiec, J., Doussan, C., Nosalewicz, A., Kondracka, K., 2013. Effect of drought and heat stresses on plant growth and yield: a review. International Agrophysics, 27: 463-477.
📄Lopes, V., Reis, A., Barata, A., Nunes, E., 2009. Morphological characterization of Portuguese Italian ryegrass landraces. Journal of Central European Agriculture, 10(1): 89-99.
📄Magar, M.M., Parajuli, A., Sah, B.P., Shrestha, J., Sakh, B.M., Koirala, K.B., Dhital, S.P., 2019. Effect of PEG induced drought stress on germination and seedling traits of maize (Zea mays L.) lines. Turkish Journal of Agricultural and Natural Sciences, 6(2): 196-205.
📄Mahmood, T., Iqbal, M.S., Li, H., Nazir, M.F., Khalid, S., Sarfraz, Z., Hu, D., Baojun, C., Geng, X., Tajo, S.M., Dev, W., Iqbal, Z., Zhao, P., Hu, G., Du, X., 2022. Differential seedling growth and tolerance indices reflect drought tolerance in cotton. BMC Plant Biology, 22(1): 331.
📄Malhi, G.S., Kaur, M., Kaushik, P., 2021. Impact of climate change on agriculture and its mitigation strategies: a review. Sustainability, 13(3): 1318.
📄Matthew, C., Van Der Linden, A., Hussain, S., Easton, H.S., Hatier, J.H.B., Horne, D.J., 2012. Which way forward in the quest for drought tolerance in perennial ryegrass?. In Proceedings of the New Zealand Grassland Association, pp. 195-200.
📄Michel, B.E., Kaufmann, M.R., 1973. The osmotic potential of polyethylene glycol 6000. Plant Physiology, 51(5): 914-916.
📄Mondal, S.S., Saha, M., Sengupta, K., Banerjee, H., 2023. Seed production of field crops (2nd fully revised and enlarged edition). New India Publishing Agency (Nipa), India, 266p.
📄Muhit, G., Kir, B., 2022. The effect of different doses of phosphorus applications on seed yield of Italian ryegrass. ISPEC Journal of Agricultural Sciences, 6(1): 82-89.
📄Onen, H., Farooq, S., Tad, S., Ozaslan, C., Gunal, H., Chauhan, B.S., 2018. The influence of environmental factors on germination of burcucumber (Sicyos angulatus) seeds: implications for range expansion and management. Weed Science, 66(4): 494-501.
📄Ozkan, S.S., Demiroglu Topcu, G., 2024. Türkiye Cumhuriyeti’nin 100. yılında yem bitkileri kültürü ve hayvan varlığına genel bir bakış. Ziraat Alanında Uluslararası Araştırma ve Değerlendirmeler Aralık 2024, Ed: K. Özrenk, A. Bolat, Serüven Publishing, Ankara, pp. 169-189.
📄Parvez, S.S., Parvez, M.M., Fujii, Y., Gemma, H., 2003. Allelopathic competence of Tamarindus indica L. root involved in plant growth regulation. Plant Growth Regulation, 41: 139-148.
📄Pei, Z.F., Ming, D.F., Liu, D., Wan, G.L., Geng, X.X., Gong, H.J., Zhou, W.J., 2010. Silicon improves the tolerance to water-deficit stress induced by polyethylene glycol in wheat (Triticum aestivum L.) seedlings. Journal of Plant Growth Regulation, 29: 106-115.
📄Pornaro, C., Serena, M., Macolino, S., Leinauer, B., 2020. Drought stress response of turf-type perennial ryegrass genotypes in a Mediterranean environment. Agronomy, 10(11): 1810.
📄Rahman, M.A., Woo, J.H., Song, Y., Lee, S.H., Hasan, M.M., Azad, M.A.K., Lee, K.W., 2022. Heat shock proteins and antioxidant genes involved in heat combined with drought stress responses in perennial rye grass. Life, 12(9): 1426.
📄Rouhi, H.R., Aboutalebian, M.A., Sharif-Zadeh, F., 2011. Effects of hydro and osmopriming on drought stress tolerance during germination in four grass species. International Journal of Agriscience, 1(2): 107-114.
📄Sari, D., 2023. Effects of PEG-induced drought stress and different boron levels on seed germination and seedling growth characteristics in chickpea (Cicer arietinum L.) and lentil (Lens culinaris Medik.). Turkish Journal of Agricultural Research, 10(2): 154-161.
📄SAS Institute, 2012. SAS/STAT® software version 9.3 user’s manual. Cary, NC: SAS Institute Inc.
📄Tassever, M.N., Uslu, O.S., 2023. Determination of feed values of some annual ryegrass (Lolium multiflorum Lam.) varieties under Kahramanmaras conditions. ISPEC Journal of Agricultural Sciences, 7(3): 701-711.
📄Yilmaz, M.B., Kisakurek, S., 2020. Effects of salt and PEG-induced drought stress on seedling performance of perennial ryegrasses (Lolium perenne L.) cultivars. Mustafa Kemal University Journal of Agricultural Sciences, 25(3): 360-369.
📄Yuce, I., Tatar, M., Kokten, K., Sarikaya, M.F., Cilesiz, Y., Karakoy, T., 2024. Determination of herbage yield and quality of some Italian ryegrass varieties in Sivas ecological conditions. ISPEC Journal of Agricultural Sciences, 8(1): 36-44.
📄Zhang, Q., Yang, L., Rue, K., 2018. Differences in seedling growth of 23 creeping bentgrass cultivars under polyethylene glycol-induced drought conditions. HortTechnology, 28(3): 327-331.
,
Kaan LEVENT
2