Bio-stimulant based nanodelivery system for pesticides with high adhesion and growth stimulation

Abstract

Pesticides are important agricultural production materials to ensure global food security, but the low utilization rate during pesticide application has caused a large amount of waste and environmental pollution. The use of pesticide carriers to deliver pesticides can help to prevent rapid release, assist in targeted release, and improve pesticide utilization. However, after completing pesticide delivery, less part of pesticide carriers has more functions and may remain in the environment, leading to material waste and environmental burden. Here, we propose that the environment-friendly carrier materials for pesticide delivery can synergistically enhance control efficacy with pesticides. Based on the bio-stimulant polyglutamic acid, amphiphilic polymers (mPEG-b-PLG) were constructed, and they assembled into nano micelle. After encapsulating prothioconazole (PTC) into the nano micelle through hydrogen bonding, electrostatic interactions and hydrophobic interactions through co-assembly, mPEG-b-PLG-PTC nanospheres with a diameter of approximately 120 nm were prepared. The nanospheres exhibit pH responsiveness for targeted release of pesticides, as well as excellent retention capacity, droplet bounce inhibition ability, and deposition capacity. At the same time, compared with commercial formulations, it has long-term antifungal properties and lower EC50, while its acute toxicity to human cells is lower, which can reduce cell apoptosis by about 63 %. It is also gratifying that the main root length, plant height, and fresh weight of wheat seedlings treated with mPEG-b-PLG have significantly improved, effectively applying carrier materials for synergistic effects. In summary, this work proposes a promising strategy to synergize pesticide carrier materials as active ingredients, providing new ideas for the integration of pesticide and fertilizer, improving pesticide utilization efficiency, and reducing environmental pollution.