Promising nanocarriers endowing non-systemic pesticides with upward translocation ability and microbial community enrichment effects in soil

The soil application of pesticides is an important method that can reduce pesticide loss, extend the validity period, and save labor input. However, the high octanol–water partitioning makes it difficult for a large number of non-systemic pesticides to be absorbed and transported by plants from the roots to the entire plant, limiting their soil applications. Herein, inspired by the uptake of nanomaterials by plants, we proposed that pesticide-loaded nanocarriers could endow non-systemic pesticides with the ability of upward translocation. Using lambda-cyhalothrin (LC) as a model pesticide, a series of LC-loaded nanogel formulations with diameters of approximately 20 nm were obtained through one-step microemulsion polymerization. The nanogels exhibited excellent storage stability, sensitive temperature-responsive release behavior, and good pyrolysis resistance. Above all, they successfully prevented LC from accumulating at the root and instead transported to the entire plant, resulting in a 7.6-fold increase in the transpiration factor (TF) value compared to that of the commercial LC microemulsion. Simultaneously, LC-loaded nanogels weakened the adsorption of soil organic matter on LC, showing good and long-term control efficiency toward aphids. Finally, the nanogels were verified to not increase toxicity to plants but to improve the abundance of the microbial community in soil. Overall, this work proposed a promising strategy to endow non-systemic pesticides with the ability of upward translocation, providing new ideas for the application of non-systematic pesticides and increasing their utilization rates.