The Nanocarrier-based Novel Strategy For Pest Control

Biological control agents such as insect viruses,Bacillus thuringiensis(Bt)toxins and RNA formulation meet the national strategic requirements of "Green Plant Protection".However,there is a long way for certain biocontrol preparations to competely replace with chemical pesticide in field.For example,Helicoverpa armigera nuclear polyhedrosis virus(HaNPV)has been applied to field control of cotton bollworm.Nevertheless,HaNPV is highly specific to its hosts,leading to narrow pesticidal spectrum and a long latency period during infection and re-infection process,which limited its popularization.The widespread application of Bt preparations or the cultivated Bt transgenic crops are facing with rapid increase in pest resistance,which has threatened the long-term use of these excellent biocontrol resources.RNA interference(RNAi)technology has been considered as the most promising targeted-pest control strategy,because of its insect selectivity and gene specificity.However,it is difficult for the foreign insecticidal double strand RNA(dsRNA)molecules to pass through the defense barriers,such as insect body wall,peritrophic membrane and cell membrane,which greatly inhibits the efficiency to target.To overcome these limitations,in this study,we developed a series of new technology platforms,through using the novel functionalized nanomaterial carriers that are developed by our collaborators and display efficient internalization to cell via endocytosis process.We made three novel applications:(1)Deliver Bt toxins to gut cell target via a protein nanocarrier for recovering pests’ sensitivity to Bt toxins and then providing new ideas for pest resistence management,which might benefit the sustainable use of this excellent biological agent.(2)Deliver HaNPV-DNA to non-host insect cells using a gene nanocarrier for overcoming virus’ specificify to hosts and expanded application-spectrum of virus,which contributed to the effective killing of non-target pests such as Agrotis ypsilon and Locusta migratoria.(3)Deliver dsRNA into pest cells via a nucleic acid nanocarrier to exert an efficient knockdown of target genes,thereby suppressing the growth and development of pests,and leading to a significant decreased pests population density.This appliction might provide a technical support for practical application of RNA pesticides.In the above three tasks,through easy operations such as feeding,driping,spraying,etc.,we achieved fast delivery of insecticidal macromolecules to target cells and good efficacy in pest control,which well meets the standard of "light and simplified plant protection".With the characteristics of high efficiency,safety,and environmental protection,the used nanocarriers might pose a vast application prospect for biological management of pests.