Lignin nanoparticles as delivery systems to facilitate translocation of methoxyfenozide in soybean (Glycine max)

Abstract

Nanoscale delivery systems have the potential to improve the effectiveness of agrochemicals while reducing their negative environmental impacts. Herein, we explore the use of lignin nanoparticles (LNPs) to enhance the translocation of methoxyfenozide (MFZ), a non-systemic pesticide, in soybean plants under hydroponic conditions. LNPs (113.8 ± 3.5 nm and zeta potential – 53.3 ± 6.9 mV) were synthesized by emulsion evaporation from lignin-graft-poly(lactic- co -glycolic) acid and MFZ was incorporated into the LNPs (2.7% w/w). Twenty eight day old soybeans were grown hydroponically and were treated with 0.01, 0.1 or 1 mg/ml of LNPs. Plants were harvested after 6, 12, and 24 h of continuous hydroponic exposure to the roots and the concentration of MFZ was quantified in root, stem, and leaf tissues. The results suggest effective and time dependent transfer of MFZ from the hydroponic suspension to the roots, and translocation from the roots to the leaves. MFZ concentrations in the 1 mg/ml treated-plants at 24 h were 519.30, 3.72 and 1.72 μg/g in the roots, stem, and leaves, at 24 h, respectively, as compared to only 28.52, 0.58, 0.39 μg/g in the plants under neat MFZ exposure. The translocation efficiency (TE) of nanodelivered MFZ ranged from 0.06 to 0.08 at 0.01 mg/ml TE, 0.01–0.05 at 0.1 mg/ml, and 0.01–0.006 at 1 mg/ml over 24 h. Even though TE was higher for free MFZ, the concentration and total amount of analyte translocated to the shoots by LNPs were higher than those of free MFZ. In conclusion, LNPs were able to significantly enhance the translocation of non-systemic MFZ from the roots to the soybean aerial tissues in 24 h. This work provides a new platform to enhance the accuracy and precision of pesticide delivery and will be a valuable tool in sustainable nano-enabled agriculture. • Nanoparticles translocate methoxyfenozide from Hoagland to roots of soybeans. • Higher amounts of methoxyfenozide reach the stems and leaves when nanodelivered than in free form. • Most of the methoxyfenozide taken by the plant concentrates in the root tissue. • Translocation of methoxyfenozide is time and concentration dependent.