National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, China; Key Laboratory of Natural Pesticide & Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, China; Guangdong Biological Pesticide Engineering Technology Research Center, South China Agricultural University, Guangzhou, China.
Zhongkai University of Agriculture and Engineering, Guangzhou, China.
Int J Biol Macromol. 2023 Dec 31;253(Pt 4):126988. doi: 10.1016/j.ijbiomac.2023.126988. Epub 2023 Sep 18.
Chlorfenapyr (CHL) is a pyrrole insecticide with a novel structure that is used to control resistant pests. However, its weak systemic activity limits its application to crop roots. Herein, a novel CHL formulation with improved effective utilization rates and suitability for root application is developed to avoid or reduce contamination caused by pesticide spraying. Accordingly, we prepared CHL@CS/CMCS nanoparticle (NP) suspensions with a particle size of approximately 100 nm using chitosan (CS) and carboxymethyl chitosan (CMCS). These suspensions exhibited better thermal stability, adhesion, permeability and systemic activity than a CHL suspension concentrate (CHL-SC). The nanoformulation deposition rate on maize leaves after spraying was 12.28 mg/kg, significantly higher than that of CHL-SC. The nanosuspension was effectively absorbed and transported by roots after irrigation and was suitable for root application. The efficacy was 89.46-92.36 % against Spodoptera frugiperda at 7 d, 7.5-17.5 times higher than that of CHL-SC. Furthermore, the CHL@CS/CMCS nanosuspension was safer for earthworms. These results suggest that chitosan-based nanoformulations improve the efficacy, utilization efficiency and active period of CHL control, providing a new approach for CHL application, reducing pollutant dispersal and the environmental impacts of pesticide application and facilitating sustainable agricultural production.
氯氟吡氧乙酸（CHL）是一种具有新颖结构的吡咯类杀虫剂，用于防治抗性害虫。然而，其较弱的内吸活性限制了其在作物根部的应用。因此，开发了一种新型的 CHL 制剂，以提高有效利用率和适合根部应用，从而避免或减少因农药喷雾而造成的污染。在此，我们使用壳聚糖（CS）和羧甲基壳聚糖（CMCS）制备了粒径约为 100nm 的 CHL@CS/CMCS 纳米颗粒（NP）悬浮液。与 CHL 悬浮剂浓缩物（CHL-SC）相比，这些悬浮液表现出更好的热稳定性、附着性、渗透性和系统活性。喷雾后，CHL-SC 在玉米叶片上的沉积率为 12.28mg/kg，显著高于 CHL-SC。纳米悬浮液在灌溉后被根部有效吸收和转运，适合根部应用。7d 时对玉米螟的防治效果为 89.46-92.36%，是 CHL-SC 的 7.5-17.5 倍。此外，CHL@CS/CMCS 纳米悬浮液对蚯蚓的安全性更高。这些结果表明，壳聚糖基纳米制剂提高了 CHL 的防治效果、利用率和有效期，为 CHL 的应用提供了新途径，减少了污染物的扩散和农药应用对环境的影响，有利于可持续农业生产。
