Research Articles
Vol. 13 No. sp2 (2026): Recent Advances in Agriculture
Physiological response of selected ornamental shrubs under salinity stress
Department of Floriculture and Landscape Architecture, SRM College of Agricultural Sciences, SRM Institute of Science and Technology, Baburayanpettai, Madhuranthakam Taluk 603 201, Chengalpattu, Tamil Nadu, India
Department of Floriculture and Landscape Architecture, SRM College of Agricultural Sciences, SRM Institute of Science and Technology, Baburayanpettai, Madhuranthakam Taluk 603 201, Chengalpattu, Tamil Nadu, India
Department of Floriculture and Landscape Architecture, SRM College of Agricultural Sciences, SRM Institute of Science and Technology, Baburayanpettai, Madhuranthakam Taluk 603 201, Chengalpattu, Tamil Nadu, India
Section of Biochemistry and Crop Physiology, SRM College of Agricultural Sciences, SRM Institute of Science and Technology, Baburayanpettai, Madhuranthakam Taluk 603 201, Chengalpattu, Tamil Nadu, India
Abstract
Salinity stress significantly affects plant growth, development and ornamental value, especially in coastal and peri-urban landscaping. This study evaluated the physiological and biochemical responses of four ornamental shrubs, Eranthemum pulchellum Andrews, Leucophyllum frutescens (Berland.) I.M.Johnst., Acalypha wilkesiana Müll.Arg. and Tabernaemontana divaricata (L.) R.Br. ex-Roem. & Schult. under varying levels of salinity (0, 20, 40 and 60 dS m-1) using sodium chloride (NaCl) and calcium chloride (CaCl2) in a 7 : 3 ratio under open-field conditions. Salinity significantly affected physiological and biochemical traits except leaf pH. Increasing salinity caused progressive reductions in chlorophyll a (Chl-a), chlorophyll b (Chl-b), total chlorophyll content, chlorophyll stability index (CSI), membrane stability index (MSI) and relative water content (RWC), while leaf electrical conductivity (EC) and total phenolic content (TPC) increased. Among the evaluated shrubs, L. frutescens exhibited superior salinity tolerance, maintaining total chlorophyll (0.16 mg g-1 FW), CSI (43.58 %), MSI (9.10 %) and RWC (58.64 %) at 60 dS m-1. In contrast, T. divaricata was highly susceptible, recording 96 % reduction in total chlorophyll and MSI and a 57 % reduction in RWC at 60 dS m-1. Eranthemum pulchellum and A. wilkesiana showed moderate physiological stability up to 20 dS m-1, indicating mild salinity tolerance, but exhibited substantial declines at higher salinity levels. Total phenolic content increased with salinity, reaching 1.89 mg GAE g-1 FW in P2 at 60 dS m-1, indicating enhanced antioxidant defence. Principal component analysis (PCA) revealed that the first three components explained 92.73 % of the total variation, with chlorophyll content, membrane stability and water status contributing most strongly to salinity tolerance. The study identifies L. frutescens as a highly salt-tolerant ornamental shrub suitable for coastal landscaping.
References
- 1. Singh KN, Chatrath R. Salinity tolerance. In: Reynalds MP, Ortiz-Monasterio I, McNab A, editors. Application of physiology in wheat breeding. Mexico: CIMMYT; 2001. p. 101–10.
- 2. Dagar JC. Salinity research in India: an overview. Bull Natl Inst Ecol. 2005;15:69–80.
- 3. Munns R. Physiological processes limiting plant growth in saline soils: some dogmas and hypotheses. Plant Cell Environ. 1993;16(1):15–24. https://doi.org/10.1111/j.1365-3040.1993.tb00840.x
- 4. Mazher AA, El-Quesni EF, Farahat MM. Responses of ornamental plants and woody trees to salinity. 2007.
- 5. Villarino GH, Mattson NS. Assessing tolerance to sodium chloride salinity in fourteen floriculture species. Hort Technology. 2011;21(5):539–45. https://doi.org/10.21273/HORTTECH.21.5.539
- 6. Carter CT, Grieve CM, Poss JA, Suarez DL. Production and ion uptake of Celosia argentea irrigated with saline wastewaters. Sci Hortic. 2005;106(3):381–94. https://doi.org/10.1016/j.scienta.2005.04.007
- 7. Alaswad AA. Transcriptomic landscapes of ornamental plants under salt and drought stress: key genes and pathways for tolerance. Front Plant Sci. 2025;16:1703649. https://doi.org/10.3389/fpls.2025.1703649
- 8. Aruna P, Kathari L. Physiological studies and nutrient analysis on the suitability of Clerodendrum inermi, Leucophyllum frutescens and Acalypha hispida shrubs under salinity. Int J Chem Stud. 2018.
- 9. Valdez-Aguilar LA, Grieve CM, Razak-Mahar A, McGiffen ME, Merhaut DJ. Growth and ion distribution affected by saline irrigation in landscape species. HortScience. 2011;46(4):632–42. https://doi.org/10.21273/HORTSCI.46.4.632
- 10. Vanlalruati VA, Kumar GU, Tiwari A. Effect of saline stress on chrysanthemum (Chrysanthemum morifolium) germplasm. Indian J Agric Sci. 2019;89(1):41–45. https://doi.org/10.56093/ijas.v89i1.86102
- 11. Bañón S, Fernández JA, Ochoa J, Sánchez-Blanco MJ. Paclobutrazol reduces salt stress effects in oleander seedlings. Eur J Hortic Sci. 2005;70:43–9. https://doi.org/10.1079/ejhs.2005/27633
- 12. Cassaniti C, Leonardi C, Flowers TJ. Effects of sodium chloride on ornamental shrubs. Sci Hortic. 2009;122(4):586–93. https://doi.org/10.1016/j.scienta.2009.06.032
- 13. Francois LE, Clark RA. Salt tolerance of ornamental shrubs, trees and iceplant. J Am Soc Hortic Sci. 1978;103(2):280–3. https://doi.org/10.21273/JASHS.103.2.280
- 14. Picchioni GA, Graham CJ. Salinity effects on Crataegus opaca. Sci Hortic. 2001;90(1–2):151–66. https://doi.org/10.1016/S0304-4238(00)00261-2
- 15. de Oliveira EV, de Lacerda CF, Neves AL, Gheyi HR, Oliveira DR, de Oliveira FI, et al. A new method to evaluate salt tolerance of ornamental plants. Theor Exp Plant Physiol. 2018;30(3):173–80. https://doi.org/10.1007/s40626-018-0112-7
- 16. Arnon DI. Copper enzymes in isolated chloroplasts. Plant Physiol. 1949;24(1):1–15. https://doi.org/10.1104/pp.24.1.1
- 17. Sairam RK, Deshmukh PS, Shukla DS. Tolerance of drought and temperature stress in wheat. J Agron Crop Sci. 1997;178(3):171–8. https://doi.org/10.1111/j.1439-037X.1997.tb00486.x
- 18. Barrs HD, Weatherley PE. Relative turgidity technique for estimating water deficits. Aust J Biol Sci. 1962;15(3):413–28. https://doi.org/10.1071/BI9620413
- 19. Singleton VL, Rossi JA Jr. Colorimetry of total phenolics. Am J Enol Vitic. 1965;16(3):144–58. https://doi.org/10.5344/ajev.1965.16.3.144
- 20. Deivasigamani P, Vijayakumar RM, Balakrishnan S, Arulmozhiselvan K, Sivakumar R. Salt stress effects on mango rootstocks. Int J Chem Stud. 2018;6(5):387–9.
- 21. Wang ZW, Li G, Liu M, Cheng X, Li LL, Li RZ, et al. Transcriptional reprogramming in mung bean under salt stress. BMC Plant Biol. 2025;25:1343. https://doi.org/10.1186/s12870-025-07281-4
- 22. Ullah F, Ayaz A, Saqib S, Parmar G, Bahadur S, Zaman W. Leaf epidermal anatomy of Scrophulariaceae. Microsc Res Tech. 2021;84(3):521–30. https://doi.org/10.1002/jemt.23608
- 23. Trivellini A, Carmassi G, Scatena G, Vernieri P, Ferrante A. Salt stress responses in Hibiscus rosa-sinensis. Mol Hortic. 2023;3(1):28. https://doi.org/10.1186/s43897-023-00075-y
- 24. Ferdosi MF, Shoaib A, Habib S, Khan KA. Salicylic acid mitigates salt stress in Gladiolus grandiflorus. Sci Rep. 2021;11:15597. https://doi.org/10.1038/s41598-021-95243-9
- 25. Kumar D, Al Hassan M, Naranjo MA, Agrawal V, Boscaiu M, Vicente O. Salinity effects on oleander physiology. PLoS One. 2017;12(9):e0185017. https://doi.org/10.1371/journal.pone.0185017
- 26. Santos CV. Salt stress effects on chlorophyll biosynthesis in sunflower. Sci Hortic. 2004;103(1):93–9. https://doi.org/10.1016/j.scienta.2004.04.009
- 27. Fornes F, Belda RM, Carrión C, Noguera V, García-Agustín P, Abad M. Saline water pre-conditioning improves drought tolerance. Sci Hortic. 2007;113(1):52–9. https://doi.org/10.1016/j.scienta.2007.01.008
- 28. Mollanejad M, Jabbarzadeh Z. Salinity tolerance strategies in Alstroemeria. Sci Rep. 2026.
- 29. Zahra N, Al Hinai MS, Hafeez MB, Rehman A, Wahid A, Siddique KHM, et al. Photosynthesis under salt stress. Plant Physiol Biochem. 2022;178:55–69. https://doi.org/10.1016/j.plaphy.2022.03.003
- 30. Hasegawa PM, Bressan RA, Zhu JK, Bohnert HJ. Plant responses to salinity. Annu Rev Plant Physiol Plant Mol Biol. 2000;51:463–99. https://doi.org/10.1146/annurev.arplant.51.1.463
- 31. Gull A, Lone AA, Wani NU. Abiotic and biotic stresses in plants. In: Abiotic and Biotic Stress in Plants. London: IntechOpen; 2019.
- 32. Parida AK, Das AB. Salt tolerance in plants. Ecotoxicol Environ Saf. 2005;60(3):324–49. https://doi.org/10.1016/j.ecoenv.2004.06.010
- 33. Ghosh D, Das T, Paul P, Dua TK, Roy S. Zinc nanoparticles mitigate salinity stress in wheat. Plant Physiol Biochem. 2024;211:108693. https://doi.org/10.1016/j.plaphy.2024.108693
- 34. Kafi M, Nabati J, Masoumi AL, Mehrgerdi MZ. Salinity and silicon effects on sorghum oxidative damage. Pak J Bot. 2011;43(5):2457–62.
- 35. Munns R, Tester M. Mechanisms of salinity tolerance. Annu Rev Plant Biol. 2008;59:651–81. https://doi.org/10.1146/annurev.arplant.59.032607.092911
- 36. Tamilselvan I, Velu P, Thangaiah A, Gunasekaran Y, Nedunchezhiyan V, Kathirvel SK, et al. Tomato physiological responses to drought. Plant Sci Today. 2024. https://doi.org/10.14719/pst.3874
- 37. Zhu JK. Plant salt tolerance. Trends Plant Sci. 2001;6(2):66–71. https://doi.org/10.1016/S1360-1385(00)01838-0
- 38. Ashraf M, Harris PJC. Biochemical indicators of salinity tolerance. Plant Sci. 2004;166(1):3–16. https://doi.org/10.1016/j.plantsci.2003.10.024
- 39. Xu L, Wang X. Phenolic compounds in horticultural plants. Int J Mol Sci. 2025;26(12):5767. https://doi.org/10.3390/ijms26125767
- 40. Mohagheghian B, Saeidi G, Arzani A. Phenolics and oxidative stress in barley under drought. BMC Plant Biol. 2025;25:709. https://doi.org/10.1186/s12870-025-06750-0
- 41. Gill SS, Tuteja N. Reactive oxygen species in abiotic stress tolerance. Plant Physiol Biochem. 2010;48(12):909–30. https://doi.org/10.1016/j.plaphy.2010.08.016
- 42. Lu H, Sun M, Ma Y, Si M, Xie J, Wang Z, et al. Foliar pH variation along water gradient. Catena. 2022;216:106408. https://doi.org/10.1016/j.catena.2022.106408
- 43. Alzahrani Y. Salinity and drought tolerance in soybean. Front Plant Sci. 2024;15:1466363. https://doi.org/10.3389/fpls.2024.1466363
- 44. Al Khallaf H, Rashad HM, Alsamadany H. Biofertilizers mitigate salinity stress in wheat. Front Plant Sci. 2025;16:1697160. https://doi.org/10.3389/fpls.2025.1697160
- 45. de Souza ER, Schaffer B, Vargas AI, de Camargo Santos A, Rodriguez EA. Salinity effects in papaya. CABI Agric Biosci. 2024;5(1):15. https://doi.org/10.1186/s43170-024-00216-3
- 46. Patwa N, Pandey V, Gupta OP, Yadav A, Meena MR, Ram S, et al. Salinity stress tolerance in wheat. BMC Plant Biol. 2024;24:875. https://doi.org/10.1186/s12870-024-05508-4
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