Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, Shandong Agricultural University, Tai'an, Shandong 271018, P. R. China.
College of Plant Protection, Shandong Agricultural University, 61 Daizong Street, Tai'an, Shandong 271018, P. R. China.
J Agric Food Chem. 2021 Feb 24;69(7):2099-2107. doi: 10.1021/acs.jafc.0c07482. Epub 2021 Feb 8.
The fungicide pyraclostrobin is highly toxic to aquatic organisms. Microencapsulation is an effective way to reduce the exposure of pyraclostrobin to aquatic organisms but it also reduces the contact probability between the fungicide and plant pathogens. Hence, winning a balance between the toxicity and bioactivity of pyraclostrobin is very necessary. In this study, triethylenetetramine (TETA), ethylenediamine (EDA), hexamethylenediamine (HAD), and isophoronediamine (IPDA) were selected as cross-linkers to prepare the pyraclostrobin-loaded polyurea microcapsules (PU-MCs) by interfacial polymerization. TETA formed the shells with the highest degree of cross-linking, the slowest release profile, and the best protection against ultraviolet (UV). In terms of MCs fabricated by diamines, higher leaking, weaker UV resistance of the shells was observed with increasing carbon skeleton. TETA-MCs showed the highest safety to zebrafish (LC of 10.086 mg/L), whereas EDA-MCs, HAD-MCs, and IPDA-MCs were 5.342, 3.967, and 0.767 mg/L, respectively. TETA-MCs had the best long-term disease management, while the control efficacies of other MCs were higher at the early stage of disease development. Overall, a balance between the aquatic toxicities and fungicidal activities of pyraclostrobin-loaded PU-MCs could be reached through a simple selection of polyamines in the fabrication.
杀菌剂吡唑醚菌酯对水生生物具有高毒性。微胶囊化是降低吡唑醚菌酯暴露于水生生物的有效方法，但也降低了杀菌剂与植物病原体接触的概率。因此，在吡唑醚菌酯的毒性和生物活性之间取得平衡是非常必要的。在这项研究中，选择三乙烯四胺（TETA）、乙二胺（EDA）、己二胺（HAD）和异佛尔酮二胺（IPDA）作为交联剂，通过界面聚合法制备吡唑醚菌酯负载的聚脲微胶囊（PU-MC）。TETA 形成了交联度最高、释放速度最慢、对紫外线（UV）保护最好的壳。就二胺制备的 MCs 而言，随着碳骨架的增加，观察到壳的漏出量增加，抗 UV 能力减弱。TETA-MCs 对斑马鱼的安全性最高（LC 为 10.086mg/L），而 EDA-MCs、HAD-MCs 和 IPDA-MCs 分别为 5.342、3.967 和 0.767mg/L。TETA-MCs 具有最佳的长期疾病管理效果，而其他 MCs 在疾病发展的早期阶段的控制效果更高。总体而言，通过在制备过程中简单选择聚胺，可以在吡唑醚菌酯负载的 PU-MC 的水生毒性和杀菌活性之间取得平衡。
