Institute of Entomology, Guizhou University, Guiyang, 550025, China.
Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region, Guiyang, 550025, China.
Exp Appl Acarol. 2022 May;87(1):31-47. doi: 10.1007/s10493-022-00718-7. Epub 2022 May 11.
Stigmaeopsis nanjingensis (Ma and Yuan) (Acari: Tetranychidae) is an important pest of bamboo-feeding behavior and silk production by the female adult mites is seriously harmful to bamboo leaves. Due to its small size, silking and cocooning, its management is difficult. This study discusses a fast and easy method for management of the pest by disturbing the spinning behavior. Stigmaeopsis nanjingensis is host specific and feeds only on bamboo leaves. Leaf margins of bamboo are highly hydrophobic, which makes dsRNA difficult to immerse. Hence, it is a challenge to apply the commonly used feeding method to inhibit gene expression in mites. In this study, we deliver dsRNA to interfere with the expression of fibroin by body wall permeation with a nanocarrier-based delivery system. The dsRNA/nanocarrier formulation droplets could enter the body cavity within 2 min after falling on the mite. The fibroin silencing efficiency was 75.4%, and the results of electron microscopy showed that dsRNA/nanocarrier damage the morphological structure of the silk thread. This study demonstrated the effectiveness of a nanocarrier-based percutaneous dsRNA delivery system in S. nanjingensis and its effect on the fibroin gene that influences the spinning behavior of S. nanjingensis. These findings may provide a new delivery system for RNAi-based control of spider mites that utilize protective webbing in the field.
南京尾孢虫（Ma and Yuan）（蜱螨目：叶螨科）是一种重要的竹子食叶害虫，雌成螨吐丝结网的行为对竹叶危害极大。由于其个体小、吐丝结网隐蔽，其防治难度较大。本研究讨论了一种快速简便的管理方法，通过干扰其吐丝行为来进行防治。南京尾孢虫是一种专性寄生螨，仅以竹叶为食。竹叶的叶缘具有很强的疏水性，使得 dsRNA 难以浸润。因此，采用常用的喂食法来抑制螨虫的基因表达具有一定的挑战性。在本研究中，我们使用基于纳米载体的递药系统，通过体壁渗透将 dsRNA 递送至体内，以干扰丝氨酸的表达。dsRNA/纳米载体制剂滴在螨虫上 2 分钟内即可进入体腔。丝氨酸的沉默效率达到 75.4%，电镜结果显示 dsRNA/纳米载体破坏了丝纤维的形态结构。本研究证明了基于纳米载体的经皮 dsRNA 递药系统在南京尾孢虫中的有效性及其对影响其吐丝行为的丝氨酸基因的影响。这些发现可能为利用保护性蛛网的叶螨的 RNAi 防治提供一种新的递药系统。
