Zheng Qun, Wang Ruifei, Qin Deqiang, Yang Liupeng, Lin Sukun, Cheng Dongmei, Huang Suqing, Zhang Zhixiang
Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, 510642, China.
College of Agriculture and Biology, Zhongkai University of Agriculture and Engineering, Guangzhou, 510642, China.
Carbohydr Polym. 2021 May 15;260:117839. doi: 10.1016/j.carbpol.2021.117839. Epub 2021 Feb 20.
The efficacy and mode of action of biodegradable chitosan (CS) and carboxymethyl chitosan (CMCS) organic polymer nanoparticles (NPs) on insects were studied. The prepared CS/CMCS-NPs were spherical with a particle size of 142.1 ± 2.0 nm. The swelling test showed that they were pH-sensitive, and the swelling rate was 554 % at pH 4.5. It was found that CS/CMCS-NPs had insecticidal efficacy against red fire ants (S. invicta). The mortality of red fire ants on the 6th day after treatment with 0.2 % and 0.06 % CS/CMCS-NPs suspensions was 98.33 ± 1.67 % and 48.33 ± 3.33 %, respectively. After CS/CMCS-NPs treatment, the food intake, growth, and development of red fire ants were inhibited; the midgut was significantly expanded; and the activity of digestive enzymes in the midgut was decreased. Our findings suggest that CS/CMCS-NPs mainly inhibited the digestion function of the midgut, leading to the death of red fire ants.
研究了可生物降解的壳聚糖（CS）和羧甲基壳聚糖（CMCS）有机聚合物纳米颗粒（NPs）对昆虫的功效和作用方式。制备的CS/CMCS-NPs呈球形，粒径为142.1±2.0nm。溶胀试验表明它们对pH敏感，在pH 4.5时溶胀率为554%。发现CS/CMCS-NPs对红火蚁（S. invicta）具有杀虫功效。用0.2%和0.06%的CS/CMCS-NPs悬浮液处理后第6天，红火蚁的死亡率分别为98.33±1.67%和48.33±3.33%。CS/CMCS-NPs处理后，红火蚁的食物摄入量、生长和发育受到抑制；中肠明显扩张；中肠消化酶的活性降低。我们的研究结果表明，CS/CMCS-NPs主要抑制中肠的消化功能，导致红火蚁死亡。
