Guangxi Key Laboratory of Agro-Environment and Agric-Products Safety, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, Guangxi 530004, People's Republic of China.
Guangxi Key Laboratory of Agro-Environment and Agric-Products Safety, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, Guangxi 530004, People's Republic of China.
Pestic Biochem Physiol. 2024 Sep;204:106018. doi: 10.1016/j.pestbp.2024.106018. Epub 2024 Jul 10.
The biological behavior of flusulfinam, a potential commercial chiral herbicide for rice, has not been well explored. Herein, the uptake of chiral flusulfinam by rice and its transport, degradation, and subcellular distribution in rice (Oryza sativa L.) were investigated. The enantiomeric fraction (EF) in roots was 0.54 during 0 d to 7 d in hydroponic laboratory conditions. The bioconcentration factor of flusulfinam enantiomers was 2.1, suggesting an absence of observed enantioselectivity in the absorption process. Notably, the EF in the shoots decreased to 0.35 on the 7th day. The translocation factors of R- and S-flusulfinam were 0.12 and 0.27, respectively, indicating a preferential transfer of the S-flusulfinam from the root to the shoot. Flusulfinam was identified in the root after spraying. The translocation factors of R- and S-flusulfinam were consistently similar, signifying the capacity for downward movement without enantioselectivity. Interestingly, the degradation half-lives of R- and S-flusulfinam in the total plant were 5.50 and 5.06 d (p < 0.05), respectively, supporting the preferential degradation of S-flusulfinam throughout the total plant. Flusulfinam primarily entered the roots via the apoplastic pathway and was subsequently transported within the plant through aquaporins and ion channels. The subcellular distribution experiment revealed the predominant accumulation of flusulfinam enantiomers in soluble components (84%) with no enantioselectivity in these processes. There was upregulation lipid transfer protein-2 and carboxylesterases15 genes, which could explain the preferential transport and degradation of S-flusulfinam. This study is important in assessing the environmental risk associated with flusulfinam and ensuring food safety.
氟磺胺草醚是一种有潜力的水稻用手性除草剂，但其生物行为尚未得到充分探究。在此，我们研究了氟磺胺草醚在水稻中的吸收及其在水稻（Oryza sativa L.）中的运输、降解和亚细胞分布。在水培实验室条件下，0 天至 7 天期间，根中的对映体分数（EF）为 0.54。氟磺胺草醚对映体的生物浓缩因子为 2.1，表明在吸收过程中未观察到对映体选择性。值得注意的是，第 7 天，茎中的 EF 降低至 0.35。R-和 S-氟磺胺草醚的转运因子分别为 0.12 和 0.27，表明 S-氟磺胺草醚优先从根转移到茎。喷药后在根中检测到氟磺胺草醚。R-和 S-氟磺胺草醚的转运因子始终相似，表明其具有向下运动的能力而没有对映体选择性。有趣的是，R-和 S-氟磺胺草醚在整株植物中的降解半衰期分别为 5.50 和 5.06 d（p<0.05），表明 S-氟磺胺草醚在整株植物中优先降解。氟磺胺草醚主要通过质外体途径进入根，随后通过水通道蛋白和离子通道在植物内运输。亚细胞分布实验表明，氟磺胺草醚对映体主要积累在可溶性成分中（84%），这些过程中没有对映体选择性。脂质转移蛋白-2 和羧酸酯酶 15 基因的上调，可能解释了 S-氟磺胺草醚的优先运输和降解。这项研究对于评估氟磺胺草醚的环境风险和确保食品安全具有重要意义。
