College of Agriculture, Guangxi University, Da Xue East Road No. 100, Nanning, 530004, Guangxi, China.
Environ Sci Pollut Res Int. 2024 Jan;31(4):6094-6105. doi: 10.1007/s11356-023-31604-3. Epub 2023 Dec 26.
Fluroxypyr-meptyl (FLUME) is heterocyclic herbicide with internal absorption and transmission characteristics. Owing to its low cost and rapid efficacy, it has been widely used to control broad-leaved weeds in wheat, corn, and rice fields. However, the uptake, translocation, accumulation, and metabolism of FLUME in rice seedlings and the extent of oxidative stress induced by it remain largely unknown, which consequently restricts the comprehensive risk assessment of FLUME residues in the environment during rice production. Hence, we systematically investigated the growth and physiological responses of rice to FLUME and analyzed its uptake, translocation, accumulation, and metabolism in rice seedlings. The results indicated that under 0-0.12 mg/L FLUME treatment, only a small proportion of FLUME was translocated upward and accumulated in rice shoots following absorption via roots, with all the translocation factor values being < 1. Moreover, the distribution and enrichment ability of FLUME in rice seedlings were greater in roots than in shoots. Furthermore, we revealed that FLUME accumulation in rice seedlings evidently inhibited their growth and activated the defense system against oxidative stress, with an increase in the activity of antioxidant and detoxifying enzymes. In addition, multiple metabolic reactions of FLUME were observed in rice seedlings, including dehalogenation, hydroxylation, glycosylation, acetylation, and malonylation. Our study provides systematic insights into the uptake, translocation, accumulation, and metabolism of FLUME in rice seedlings as well as the oxidative stress induced by FLUME accumulation, which can help improve FLUME applications and environmental risk assessments in crops.
氟吡草腙（FLUME）是一种具有内吸和传导特性的杂环类除草剂。由于其成本低、效果快，已广泛用于小麦、玉米和稻田阔叶杂草的防治。然而，FLUME 在水稻幼苗中的吸收、转运、积累和代谢，以及其诱导的氧化应激程度，在很大程度上仍不清楚，这限制了在水稻生产过程中对环境中 FLUME 残留的综合风险评估。因此，我们系统地研究了 FLUME 对水稻生长和生理的影响，并分析了其在水稻幼苗中的吸收、转运、积累和代谢。结果表明，在 0-0.12 mg/L FLUME 处理下，FLUME 仅小部分被吸收后通过根部向上转运并积累在稻株中，所有转运因子值均<1。此外，FLUME 在水稻幼苗中的分布和富集能力在根部大于在稻株中。此外，我们发现 FLUME 在水稻幼苗中的积累明显抑制了其生长，并激活了抗氧化应激的防御系统，导致抗氧化和解毒酶的活性增加。此外，在水稻幼苗中还观察到 FLUME 的多种代谢反应，包括脱卤、羟化、糖基化、乙酰化和丙二酰化。本研究系统地研究了 FLUME 在水稻幼苗中的吸收、转运、积累和代谢以及 FLUME 积累诱导的氧化应激，这有助于提高 FLUME 在作物中的应用和环境风险评估。
