The effect of 24-epibrassinolide on chlorophyll parameters, physiological and biochemical traits of lettuce (Lactuca sativa L.) under salt stress.

Chaghakaboodi, Zeinab; Mousavi, Seyed Hassan; IMANI, MOHAMMADREZA; Ranjbar, Faranak

doi:10.30473/cb.2025.74198.2006

The effect of 24-epibrassinolide on chlorophyll parameters, physiological and biochemical traits of lettuce (Lactuca sativa L.) under salt stress.

Document Type : Research Paper

Authors

¹ Department of Plant Production Engineering and Genetics, Campus of Agriculture and Natural Resources, Faculty of agriculture, Razi University. Kermanshah, Iran.

² 2. Greenhouse and Controlled Environments Research Institute, Horticultural Sciences Research Institute, Agricultural Research, Education and Extension Organization, Karaj, Iran.

³ 3. Department of Soil Science and Engineering, Faculty of Agriculture and Natural Resources, Razi University, Kermanshah, Iran.

10.30473/cb.2025.74198.2006

Abstract

Salinity stress affects plant growth and productivity by causing ion toxicity, disrupting water uptake, and altering hormonal balance. With the shift towards greenhouse-based vegetable and fruit production, selecting and evaluating lettuce genotypes with traits like heat, salinity, and drought tolerance is crucial to meeting production goals. Therefore, in this project, to identify salt-tolerant lines, promising lines numbered 20, 7, and 4, along with the local cultivar ‘Setareh’ and the foreign cultivars ‘Batavia’ and ‘Mignonette,’ were tested in a factorial experiment arranged in a completely randomized design with four replications in the greenhouse of the College of Agriculture and Natural Resources at Razi University, Kermanshah, during the 2023-2024 growing season. In this study, pots were irrigated with specific salinity levels (control, concentration of 10 mM NaCl/5 mM CaCl₂, concentration of 20 mM NaCl/10 mM CaCl₂, and concentration of 30 mM NaCl/15 mM CaCl₂). Salinity treatments were applied simultaneously after the third or fourth leaf stage. Various traits, including chlorophyll fluorescence, leaf greenness, total soluble sugar content, total phenol content, and total flavonoid content, were measured. The results showed that with increasing salinity levels, chlorophyll fluorescence parameters such as Fv/Fm (maximum quantum efficiency of PSII) and Y(PSII) (effective quantum yield of PSII) decreased, indicating a reduction in the photosynthetic efficiency of lettuce plant genotypes. This could lead to a decrease in plant growth and productivity. Additionally, the increase in salinity stress levels resulted in elevated levels of phytochemical compounds such as total soluble sugar content, total phenol content, and total flavonoid content.

Keywords

Main Subjects

Biotic and Abiotic stress

References

Adhikari, N. D., Simko, I., & Mou, B. (2019). Phenomic and physiological analysis of salinity effects on lettuce. Sensors, 19(21), 4814. Ahmed, S., Ahmed, S., Roy, S. K., Woo, S. H., Sonawane, K. D., & Shohael, A. M. (2019). Effect of salinity on the morphological, physiological and biochemical properties of lettuce (Lactuca sativa L.) in Bangladesh. Open Agriculture, 4(1), 361-373. Babaousmail, M., Nili, M. S., Brik, R., Saadouni, M., Yousif, S. K., Omer, R. M., & El-Taher, A. M. (2022). Improving the tolerance to salinity stress in lettuce plants (Lactuca sativa L.) using exogenous application of salicylic acid, yeast, and zeolite. Life, 12(10), 1538. Boughalleb, F., Abdellaoui, R., Mahmoudi, M., & Bakhshandeh, E. (2020). Changes in phenolic profile, soluble sugar, proline, and antioxidant enzyme activities of Polygonum equisetiforme in response to salinity. Turkish Journal of Botany, 44(1), 25-35. Boukema, I. W., Hazekamp, T.H., & Hintum, T.H.J.L. (2007). The CGN Collection Reviews: The CGN Lettuce Collection. Wageningen, Centre for Genetic Resource. 2-5. Breś, W., Kleiber, T., Markiewicz, B., Mieloszyk, E., & Mieloch, M. (2022). The effect of NaCl stress on the response of lettuce (Lactuca sativa L.). Agronomy, 12(2), 244. Chang, C.C., Yang, M.H., Wen, H.M., & Chern, J.C. (2002). Estimation of total flavonoid content in propolis by two complementary colorimetric methods. Journal Food Drug Anal., 10, 178-82. Costa, S. F., Martins, D., Agacka-Mołdoch, M., Czubacka, A., & de Sousa Araújo, S. (2018). Strategies to alleviate salinity stress in plants. Salinity Responses and Tolerance in Plants, Volume 1: Targeting Sensory, Transport and Signaling Mechanisms, 307-337. Dai, M., Tan, X., Ye, Z., Chen, X., Zhang, Y., Ruan, Y., & Kong, D. (2024). Analysis of lettuce transcriptome reveals the mechanism of different light/dark cycle in promoting the growth and quality. Frontiers in Plant Science, 15, 1394434. DeVries, I. M. (1997). Origin and domestication of (Lactuca sativa L). Genet Resource and Crop Evolution, 44, 165-174. Ekinci, M., Yildirim, E., Dursun, A., & Turan, M. (2012). Mitigation of salt stress in lettuce (Lactuca sativa L. var. Crispa) by seed and foliar 24-epibrassinolide treatments. HortScience, 47(5), 631-636. Food and Agriculture Organization of the United State, 2014. Ghassemi-Golezani, K., Hosseinzadeh-Mahootchi, A., & Farhangi-Abriz, S. (2020). Chlorophyll a fluorescence of safflower affected by salt stress and hormonal treatments. SN Applied Sciences, 2, 1-9. Guo, J., Zhou, X., Wang, T., Wang, G., & Cao, F. (2020). Regulation of flavonoid metabolism in ginkgo leaves in response to different day-night temperature combinations. Plant Physiology and Biochemistry, 147, 133-140. Kalaji, H. M., Bosa, K., Kościelniak, J., & Żuk-Gołaszewska, K. (2011). Effects of salt stress on photosystem II efficiency and CO2 assimilation of two Syrian barley landraces. Environmental and Experimental Botany, 73, 64-72. Kataria, S., & Verma, S. K. (2018). Salinity Stress Responses and Adaptive Mechanisms in Major Glycophytic Crops: The Story So Far. in Salinity Responses and Tolerance in Plants, vol. 1, pp. 1–39. Krause, A.G., & Weis, E. (1991). Chlorophyll fluorescence and photosynthesis: the basics. Annual review of plant biology, 42(1), 313-349. Kumar, K., & Saddhe, A.A. (2018). Targeting aquaporins for conferring salinity tolerance in crops. Salinity Responses and Tolerance in Plants, Volume 1: Targeting Sensory, Transport and Signaling Mechanisms,65-84. Lebeda, A. Ryder, E. J. Grube, R. Dolezalova, I., & Kristkova, E. (2007). Lettuce (Asteraceae; Lactuca spp). In: SINGH R.J. (ed.), Genetic Resources, Chromosome Engineering, and Crop Improvement, Vol. 3, 377-472. Marhaenanto, B., Aningtyas, P. W., Putraa, B. T. W., Soedibyo, D. W., & Syahputra, W. N. H. (2025). Estimating Flavonoid and Nitrogen Status of Guava Leaves Using E-Nose and SPAD Meter. Agricultural Research, 1-14. Mihaljević, I., Lepeduš, H., Šimić, D., Vuletić, M. V., Tomaš, V., Vuković, D., & Zdunić, Z. (2020). Photochemical efficiency of photosystem II in two apple cultivars affected by elevated temperature and excess light in vivo. South African journal of botany, 130, 316-326. Netto, A. T., Campostrini, E., de Oliveira, J. G., & Bressan-Smith, R. E. (2005). Photosynthetic pigments, nitrogen, chlorophyll a fluorescence and SPAD-502 readings in coffee leaves. Scientia horticulturae, 104(2), 199-209. Pandjaitan, N., Howard, L. R., Morelock, T., & Gil, M. I. (2005). Antioxidant capacity and phenolic content of spinach as affected by genetics and maturation. Journal Agric. Food Chem, 53, 8618 - 23. Pavli, O.I., Kempapidis, K., Maggioros, L., Foti, C., Panagiotaki, E., & Khah E.M. (2021). Response of Lettuce Germplasm to Salt Stress at Different Developmental Stages. Annals of Agricultural & Crop Sciences, 6(5). Sardar, H., Khalid, Z., Ahsan, M., Naz, S., Nawaz, A., Ahmad, R., & Abou Fayssal, S. 2023. Enhancement of salinity stress tolerance in lettuce (Lactuca sativa L.) via foliar application of nitric oxide. Plants, 12(5), 1115. Shlegl, H. G., 1986. Die verwertung orgngischer souren durch chlorella lincht. Plant Sciences, 41, 47-51. Sim, C. C., Zaharah, A. R., Tan, M. S., & Goh, K. J. (2015). Rapid determination of leaf chlorophyll concentration, photosynthetic activity and NK concentration of Elaies guineensis via correlated SPAD-502 chlorophyll index. Takai, T., Kondo, M., Yano, M., & Yamamoto, T. (2010). A quantitative trait locus for chlorophyll