Effectiveness of chitosan nanohydrogel mediated encapsulation of EcR dsRNA against the whitefly, Bemisia tabaci Asia-I (Gennedius) (Hemiptera: Aleyordidae)

Pestic Biochem Physiol. 2024 Jan:198:105712. doi: 10.1016/j.pestbp.2023.105712. Epub 2023 Nov 29.

Abstract

Bemisia tabaci is a global invasive pest causing substantial loss on several economically important crops and has developed a very high level of resistance to insecticides making current management practices ineffective. Thus, the novel pest management strategy like RNA interference (RNAi) has emerged as a potential molecular tool in the management of insect pests particularly B. tabaci. The present study investigated RNAi mediated silencing of the Ecdysone Receptor (EcR) gene in B. tabaci Asia-I using biodegradable Chitosan Nanoparticles (CNPs) hydrogel containing EcR dsRNA. The formation of nanohydrogel and dsRNA loading were characterized by gel retardation assay, scanning electron microscopy (SEM); transmission electron microscopy (TEM) and Fourier transform infrared microscopy (FTIR). The stability of CNPs/dsRNA was assessed by exposure to direct sunlight and UV light for different time periods. The CNPs/dsRNA exhibited increased stability over the untreated control and further confirmed by bioassay studies which yielded mortality over 80% and effectively down regulated the expression of the EcR gene as confirmed by qRT-PCR analysis. These investigations provide potential avenues for advancing innovative pest management strategies using biopolymer CNPs hydrogel, which can enhance the efficiency of dsRNA as a safe and targeted solution in the management of whiteflies.

Keywords: Bioassay; Biopolymer; Gene silencing; Nanohydrogel; dsRNA.

MeSH terms

  • Animals
  • Chitosan* / metabolism
  • Chitosan* / pharmacology
  • Hemiptera* / genetics
  • Hemiptera* / metabolism
  • Hydrogels / metabolism
  • RNA Interference
  • RNA, Double-Stranded / genetics
  • RNA, Double-Stranded / metabolism
  • Receptors, Steroid*

Substances

  • ecdysone receptor
  • Chitosan
  • RNA, Double-Stranded
  • Hydrogels
  • Receptors, Steroid