Biochar Herbicide Protection Pods for Mitigating Herbicide Sensitivity in Tomato Plants

Tomato is a major crop, and efforts are ongoing to enhance its resilience to biotic and abiotic stresses. Weed management remains a key challenge, prompting the search for sustainable alternatives to reduce the impact of excessive herbicide use. Biochar is a promising alternative, as it enriches the soil, improves its water retention capacity, promotes its regeneration and increased fertility, delays nutrient leaching, and improves fertilizer use efficiency. This study aimed to investigate the efficiency of biochar use in mitigating stress caused by different herbicides. Two different biochar materials, Douglas fir and rice husk, were used. Tomato seeds were sown in pots and arranged in a randomized design. At the 4V stage (28 days after sowing), the herbicides S-metolachlor, metribuzin, and halosulfuron were applied. Plant length, injury, antioxidant enzyme activity, ascorbate peroxidase (APX), catalase (CAT), guaiacol peroxidase (GPOD), glutathione reductase (GR), and hydrogen peroxide content (H2O2) were assessed 7 and 14 days after herbicide application. Plants treated with biochar and submitted to herbicide treatments showed significantly higher growth parameters and fewer injuries when compared to plants treated with herbicides without biochar. The antioxidant response of the plants followed the same trend; smaller plants with more injuries showed greater H2O2 accumulation and significantly higher antioxidant enzyme activity. These findings highlight the protective effect of biochar, particularly Douglas fir biochar, as it effectively mitigated herbicide-induced oxidative stress and helped maintain plant growth and structural integrity under treatment conditions.