The mitigating effects of Rhizophagus irregularis on Haloxyfop-R-Omethylester-induced harmful biochemical effects in...

Herbicides, including Super Gallant (Haloxyfop-R-Omethylester), play a vital role in chemical weed control but can have detrimental effects on plant physiology and biochemistry. This study investigated the impact of Super Gallant-induced stress and the protective effects of Rhizophagus irregularis (previously known as Glomus intraradices) on the proline, protein, soluble sugar, and malondialdehyde (MDA) contents in the shoots and roots of sunflower (Helianthus annuus L.). The activities of antioxidant enzymes, including ascorbate peroxidase (APX), guaiacol peroxidase (GPX), catalase (CAT), and acetyl-CoA carboxylase (ACCase), were also assessed. The results revealed that AM fungi mitigated the adverse effects of Super Gallant by enhancing the antioxidant system and increasing the accumulation of proline and soluble sugars, thereby improving the plant's defense mechanisms. ACCase activity was elevated in AM-inoculated plants, and soluble protein accumulation was observed as an adaptive response under chemical stress. However, MDA levels, a marker of oxidative damage, increased with higher herbicide concentrations, indicating limitations in the protective role of AM fungi under certain conditions. This study highlights the critical role of AM fungi in enhancing the physiological responses of sunflower to chemical stress and demonstrates that AM fungi can serve as a sustainable strategy for managing chemical stress in agricultural systems. These findings provide a foundation for future research aimed at optimizing the use of AM fungi and other biotic agents to address environmental stress challenges effectively.