Biotoxicity Evaluation of a Cationic Star Polymer on a Predatory Ladybird and Cooperative Pest Control by Polymer-Delivered Pesticides and Ladybird
Biotoxicity Evaluation of a Cationic Star Polymer on a Predatory Ladybird and Cooperative Pest Control by Polymer-Delivered Pesticides and Ladybird
复制标题
DOI：
10.1021/acsami.1c24077
复制
发表时间：
2022-01-24
影响因子：
9.5
通讯作者：
Yan, Shuo
中科院分区：
文献类型：
--
作者：
Dong, Min;Chen, Dingming;Yan, Shuo
尽管纳米载体在农业领域显示出巨大的潜力，但纳米载体的生物毒性是大规模应用的主要问题。本文合成了一种阳离子型星星聚合物（SPc）作为农药纳米载体/助剂，以评价其对广泛使用的捕食性瓢虫（异色瓢虫）的安全性。在极高浓度下施用SPc对瓢虫卵的孵化几乎没有影响，但通过浸泡法和喂食法处理，导致瓢虫幼虫死亡，其LC 50值分别为43.96和19.85 mg/mL。经口饲喂SPc显著下调了许多膜蛋白基因和溶酶体基因的表达，并对肠道组织细胞膜和细胞核造成了明显的损伤，其致死机制可能是SPc介导的膜损伤。此外，口服SPc增加了瓢虫肠道中沙雷氏菌的相对丰度，导致细菌感染。瓢虫与SPc-噻虫嗪/苦参碱混用，对绿色桃蚜的防效均在80%以上，说明二者混用可克服瓢虫的缓效特性。据我们所知，这是第一次尝试研究聚合物介导的对天敌的致死机制，并探索将SPc农药与天敌共施用用于害虫管理的可能性。
Although employing nanocarriers for gene/drug delivery shows great potential in agricultural fields, the biotoxicity of nanocarriers is a major concern for large-scale applications. Herein, we synthesized a cationic star polymer (SPc) as a pesticide nanocarrier/adjuvant to evaluate its safety against a widely used predatory ladybird (Harmonia axyridis). The application of SPc at extremely high concentrations nearly did not influence the hatching of ladybird eggs but it led to the death of ladybird larvae at lethal concentration 50 (LC50) values of 43.96 and 19.85 mg/mL through the soaking and feeding methods, respectively. The oral feeding of SPc downregulated many membrane protein genes and lysosome genes significantly, and the cell membrane and nucleus in gut tissues were remarkably damaged by SPc application, revealing that the lethal mechanism might be SPc-mediated membrane damage. Furthermore, the oral feeding of SPc increased the relative abundance of Serratia bacteria in ladybird guts to result in bacterial infection. Coapplication of ladybird and SPc-loaded thiamethoxam/matrine achieved desired control efficacies of more than 80% against green peach aphids, revealing that the coapplication could overcome the slow-acting property of ladybirds. To our knowledge, this is the first attempt to investigate the polymer-mediated lethal mechanism toward natural enemies and explore the possibility of coapplying SPc-loaded pesticides and natural enemies for pest management.