Synergistic effects of sugarcane biochar and glycine betaine foliar spray on lettuce (Lactuca sativa L.) physiological performance, biochemical markers, metabolites, and antioxidative features under wastewater irrigated soil
Year: 2026
Type: article
Abstract: Wastewater irrigation can alleviate freshwater shortages, but its continued use may impair soil quality and crop performance by accumulating salts and heavy metals (HMs). Biochar (BC) can reduce HM bioavailability in soil, whereas glycine betaine (GB) can enhance plant tolerance by improving osmotic adjustment and antioxidant defence. However, their combined role in mitigating HM stress induced by wastewater in lettuce ( Lactuca sativa L.) remains insufficiently understood. Therefore, a pot experiment was conducted using two irrigation sources, canal water (CW) and Madhuana drain wastewater (MDWW), together with four amendment treatments: control, BC (3% w/w), foliar-applied GB (50 mM), and BC + GB. Morphological, physiological, biochemical, and antioxidant attributes were evaluated and analysed using analysis of variance at P < 0.05 . Compared with CW, MDWW irrigation significantly reduced shoot length (11.0%), root length (63.5%), fresh weight (84.9%), dry weight (27.3%), and leaf number, while also decreasing photosynthetic pigments, gas-exchange traits, and membrane stability. Wastewater stress further increased oxidative damage and HM accumulation in lettuce tissues. Among all treatments, the combined application of BC + GB provided the strongest protection by improving growth, photosynthetic efficiency, metabolite accumulation, and antioxidant enzyme activity, while reducing oxidative stress indicators. Importantly, BC + GB also lowered cadmium, chromium, and lead accumulation by 68%, 46%, and 49%, respectively, compared with the untreated wastewater control. Overall, the integrated BC and GB application mitigated wastewater-induced stress in lettuce by improving physiological resilience, enhancing biochemical defense, and reducing HM uptake under contaminated irrigation, thereby promoting safer and more sustainable lettuce production.
Institutions: University of Agriculture Faisalabad, Chinese Academy of Sciences, Northeast Institute of Geography and Agroecology, Gansu Agricultural University, Islamia University of Bahawalpur, Nakhchivan University, Nakhchivan State University, Princess Nourah bint Abdulrahman University, United Arab Emirates University
Language: English
Subfield: Waste Management and Disposal
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,930
OpenAlex ID: W7168187133