Effects of Treated Wastewater Irrigation on Chlorophyll Content, Leaf Color, and Gene Expression in Tomato (Solanum lycopersicum L.)

Authors

DOI:

https://doi.org/10.24925/turjaf.v13i12.4236-4241.8396

Keywords:

tomato, treated wastewater, gene expression, SlDREB2, SlARF9, SlEXP1

Abstract

This study was investigated the effects of treated wastewater irrigation on physiological traits and gene expression in tomato plants (Solanum lycopersicum L.) during the early developmental stage. Two treatments which are control (tap water) and treated wastewater irrigation were compared. Physiological parameters, including SPAD values and leaf color, were assessed, while the expression of growth and stress-related genes (SlDREB2, SlARF9, and SlEXP1) was quantified using RT-qPCR with three biological replicates. Relative expression levels were calculated following the 2^−ΔΔCt method. The results demonstrated that treated wastewater irrigation significantly enhanced chlorophyll content (SPAD) in tomato leaves and shifted leaf coloration toward darker, greenish hues. At the molecular level, a pronounced upregulation of SlDREB2 was observed, whereas SlEXP1 expression was suppressed. Although SlARF9 expression showed an increase in relative to the control, this change was not statistically significant. Collectively, these findings suggest that treated wastewater irrigation can enhance photosynthetic capacity in tomato plants in the short term, while simultaneously activating abiotic stress signaling pathways and constraining certain growth-associated mechanisms.

References

Adegoke, A. A., Amoah, I. D., Stenström, T. A., Verbyla, M. E., & Mihelcic, J. R. (2018). Epidemiological evidence and health risks associated with agricultural reuse of partially treated and untreated treated wastewater: a review. Frontiers in Public Health, 6, 337. https://doi.org/ 10.3389/fpubh.2018.00337

Akhkha, A., Boutraa, T., & Al-Shoaibi, A. K. (2017). The influence of al-Madinah al-Munawwara treated and untreated domestic treated wastewater on growth and physiology of three tomato (Lycopersicon esculentum Mill.) genotypes. Pak. J. Bot, 49(3), 879-890.

Bouzroud, S., Gouiaa, S., Hu, N., Bernadac, A., Mila, I., Bendaou, N., ... & Zouine, M. (2018). Auxin response factors (ARFs) are potential mediators of auxin action in tomato response to biotic and abiotic stress (Solanum lycopersicum). PloS one, 13(2), e0193517. https://doi.org/ 10.1371/journal.pone.0193517

Brummell, D. A., Harpster, M. H., Civello, P. M., Palys, J. M., Bennett, A. B., & Dunsmuir, P. (1999). Modification of expansin protein abundance in tomato fruit alters softening and cell wall polymer metabolism during ripening. The Plant Cell, 11(11), 2203-2216. https://doi.org/10.1105/tpc.11.11.2203

Cho, H. T., & Cosgrove, D. J. (2002). Regulation of root hair initiation and expansin gene expression in Arabidopsis. The Plant Cell, 14(12), 3237-3253. https://doi.org/10.1105/tpc.006437

Commission Internationale de I’Eclairage (CIE). (1976). Official recommendations on uniform colorspace, color difference equations and metric color terms (CIE Publication No. 15). Bureau Central de la CIE.

Cosgrove, D. J. (2000). Loosening of plant cell walls by expansins. Nature, 407(6802), 321–326. https://doi.org/10.1038/35030000

De Jong, M., Wolters‐Arts, M., Feron, R., Mariani, C., & Vriezen, W. H. (2009). The Solanum lycopersicum auxin response factor 7 (SlARF7) regulates auxin signaling during tomato fruit set and development. The Plant Journal, 57(1), 160-170. https://doi.org/10.1111/j.1365-313X.2008.03671.x

FAOSTAT. Production: Crops and livestock products. Retrieved 10 September 2025, from http://www.fao.org/faostat/en/#data/QCL

Gassama, U. M., Puteh, A. B., Abd-Halim, M. R., & Kargbo, B. (2015). Influence of municipal treated wastewater on rice seed germination, seedling performance, nutrient uptake, and chlorophyll content. Journal of Crop Science and Biotechnology, 18(1), 9-19. https://doi.org/10.3390/w12020607

Guilfoyle, T. J., & Hagen, G. (2007). Auxin response factors. Current Opinion in Plant Biology, 10(5), 453-460. https://doi.org/10.1016/j.pbi.2007.08.014

Guo, J., & Wang, M. H. (2011). Expression profiling of the DREB2 type gene from tomato (Solanum lycopersicum L.) under various abiotic stresses. Horticulture, Environment, and Biotechnology, 52(1), 105-111. https://doi.org/10.1007/s13580-011-0125-5

Hajihashemi, S., Mbarki, S., Skalicky, M., Noedoost, F., Raeisi, M., & Brestic, M. (2020). Effect of treated wastewater irrigation on photosynthesis, growth, and anatomical features of two wheat cultivars (Triticum aestivum L.). Water, 12(2), 607. https://doi.org/ 10.3390/w12020607

Hichri, I., Muhovski, Y., Clippe, A., Žižková, E., Dobrev, P. I., Motyka, V., & Lutts, S. (2016). SlDREB2, a tomato dehydration‐responsive element‐binding 2 transcription factor, mediates salt stress tolerance in tomato and Arabidopsis. Plant, cell & environment, 39(1), 62-79. https://doi.org/10.1111/pce.12591

Kesari, K. K., Soni, R., Jamal, Q. M. S., Tripathi, P., Lal, J. A., Jha, N. K., ... & Ruokolainen, J. (2021). Treated wastewater treatment and reuse: a review of its applications and health implications. Water, Air, & Soil Pollution, 232(5), 208. https://doi.org/ 10.1007/s11270-021-05154-8

Lata, C., & Prasad, M. (2011). Role of DREBs in regulation of abiotic stress responses in plants. Journal of experimental botany, 62(14), 4731-4748. https://doi.org/10.1093/jxb/err210

Livak KJ., & Schmittgen TD (2001) Analysis of Relative Gene Expression Data Using Real-Time Quantitative PCR and the 2−ΔΔCT method. Methods 25(4): 402-408. https://doi.org/ 10.1006/meth.2001.1262

Lu, Y., Liu, L., Wang, X., Han, Z., Ouyang, B., Zhang, J., & Li, H. (2016). Genome-wide identification and expression analysis of the expansin gene family in tomato. Molecular Genetics and Genomics, 291(2), 597-608. https://doi.org/ 10.1007/s00438-015-1133-4

Marowa, P., Ding, A., & Kong, Y. (2016). Expansins: roles in plant growth and potential applications in crop improvement. Plant Cell Reports, 35(5), 949-965. https://doi.org/10.1007/s00299-016-1948-4

Paul, S., & Veerabhadraswamy, A. L. (2021, March). Effects of treated wastewater on vegetative growth and pigmentation of forage crops. https://doi.org/10.21203/rs.3.rs-274777/v1

Pedrero, F., Kalavrouziotis, I., Alarcón, J. J., Koukoulakis, P., & Asano, T. (2010). Use of treated municipal wastewater in irrigated agriculture-Review of some practices in Spain and Greece. Agricultural Water Management, 97(9), 1233-1241. https://doi.org/10.1016/j.agwat.2010.03.003

Pirona, R., Frugis, G., Locatelli, F., Mattana, M., Genga, A., & Baldoni, E. (2023). Transcriptomic analysis reveals the gene regulatory networks involved in leaf and root response to osmotic stress in tomato. Frontiers in Plant Science, 14, 1155797. https://doi.org/10.3389/fpls.2023.1155797

Suzuki, N., Rivero, R. M., Shulaev, V., Blumwald, E., & Mittler, R. (2014). Abiotic and biotic stress combinations. New Phytologist, 203(1), 32-43. https://doi.org/10.1111/nph.12797

Qadir, M., Drechsel, P., Jiménez Cisneros, B., Kim, Y., Pramanik, A., Mehta, P., & Olaniyan, O. (2020, February). Global and regional potential of treated wastewater as a water, nutrient and energy source. In Natural resources forum (Vol. 44, No. 1, pp. 40-51). Oxford, UK: Blackwell Publishing Ltd. https://doi.org/ 10.1111/1477-8947.12187

Qin, F., Kakimoto, M., Sakuma, Y., Maruyama, K., Osakabe, Y., Tran, L. S. P., ... & Yamaguchi‐Shinozaki, K. (2007). Regulation and functional analysis of ZmDREB2A in response to drought and heat stresses in Zea mays L. The Plant Journal, 50(1), 54-69. https://doi.org/10.1111/j.1365-313X.2007.03034.x

Tenhaken, R. (2015). Cell wall remodeling under abiotic stress. Frontiers in Plant Science, 5, 771. https://doi.org/10.3389/fpls.2014.00771

Toze, S. (2006). Reuse of effluent water—benefits and risks. Agricultural water management, 80(1-3), 147-159. https://doi.org/ 10.1016/j.agwat.2005.07.010

Trotta, V., Baaloudj, O., & Brienza, M. (2024). Risks associated with treated wastewater reuse in agriculture: investigating the effects of contaminants in soil, plants, and insects. Frontiers in Environmental Science, 12, 1358842. https://doi.org/ 10.3389/fenvs.2024.1358842

Tufenkci S and Yerli C (2023) Physical and physiological properties and mineral content of curly lettuce grown by applying different rates of biochar to the soil with varying irrigation water levels. International Journal of Agricultural and Wildlife Sciences, 9(2), 205-217. https://doi.org/ 10.24180/ijaws.1255958

Ungureanu, N., Vlăduț, V., & Voicu, G. (2020). Water scarcity and wastewater reuse in crop irrigation. Sustainability, 12(21), 9055. https://doi.org/10.3390/su12219055

Wu, Y., & Cosgrove, D. J. (2000). Adaptation of roots to low water potentials by changes in cell wall extensibility and cell wall proteins. Journal of Experimental Botany, 51(350), 1543–1553. https://doi.org/10.1093/jexbot/51.350.1543

Yerli, C. (2023). The effects of biochar pyrolyzed at varying temperatures and different water types on the properties of lettuce and soil. Water, Air, & Soil Pollution, 234(8), 552. https://doi.org/10.1007/s11270-023-06582-4

Zhang, Q., Zhao, Y., Zhang, J., Li, X., Ma, F., Duan, M., ... & Li, H. (2021). The responses of the lipoxygenase gene family to salt and drought stress in foxtail millet (Setaria italica). Life, 11(11), 1169. https://doi.org/ 10.3390/life11111169

Zouine, M., Fu, Y., Chateigner-Boutin, A. L., Mila, I., Frasse, P., Wang, H., ... & Bouzayen, M. (2014). Characterization of the tomato ARF gene family uncovers a multi-levels post-transcriptional regulation including alternative splicing. PloS one, 9(1), e84203. https://doi.org/10.1371/journal.pone.0084203

Downloads

Published

28.12.2025

Issue

Section

Research Paper