Insights into mechanism of uptake, translocation, and subcellular distribution of chlorpyrifos in two varieties of Withania somnifera L. Dunal.

The uptake, translocation, and accumulation of chlorpyrifos (CP), a persistent organophosphate pesticide, in medicinal plants such as Withania somnifera is essential for ensuring their safe cultivation. This study explores the dynamics of chlorpyrifos (CP) in two Withania somnifera varieties, NIMTLI 118 and Poshita, that were cultivated hydroponically. The results revealed that Poshita accumulated 1.2 to 1.6 times more CP compared to NIMTLI 118, owing to its increased lipid content in roots. The reduced uptake rate constant in the shoot compared to the root indicated the reduced upward translocation of CP in both varieties. The CP content was greater in the cell organelle than in the cell wall, and not present in the cell soluble fraction of both varieties. CP uptake occurs by a passive process via the apoplast. The study demonstrated the possibility of hydrogen bonds, electrostatic and hydrophobic interactions of chlorine, sulfur, phosphorus, and carbon groups of CP with polar and charged amino acid residues of nsLTP. Further, detailed molecular studies are required to understand the role of nsLTP in transporting CP.