Use of interfering rnas directed against the cholinergic system for controlling insect pests

Abstract

The present invention relates to a method for controlling insect pests by RNA-interference-induced inhibition of the translation of an mRNA of a target gene belonging to the cholinergic system of the insect. The invention also relates to an insecticide composition comprising a double-stranded RNA or an antisense oligonucleotide and a transfection agent or a solvent. The invention also relates to an interfering RNA in which the dsRNA or antisense oligonucleotide inhibits the translation of mRNAs corresponding to the coding sequence of any one of the genes of the group of neuronal α sub-units of the nicotinic receptor, of the genes of group of neuronal β sub-units of the nicotinic receptor, and isoforms thereof, to any one of the nucleotide sequences of the genes encoding the auxiliary molecules and proteins of the nicotinic receptor, and isoforms thereof, or to the DNA sequence encoding a protein of the nicotinic receptor interactome. The invention further relates to the uses of the interfering RNA or antisense oligonucleotide as a bioinsecticide, as an agent for synergising the insecticidal effect of an insecticide or of a molecule with insecticidal effect against an insect pest, and as an agent for restoring the sensitivity of an insect pest with respect to an insecticide.

Description

[0001]Description Title of the invention: Use of interfering RNAs directed against the cholinergic system to combat harmful insects Background of the invention The present invention relates to the field of combating harmful insects. Taking into consideration in particular the implementation of the Ecophyto II+ plan which aims to reduce the use of phytosanitary products by 50%, the need for means of combating harmful insects is particularly pressing. These insects represent a nuisance both from the point of view of public health and the smooth running of human activities, whether domestic or professional. The presence of cockroaches, bedbugs within a home as well as the infestation of crops by aphids, leafhoppers, weevils or others, has a deleterious effect on human activity. In fact, modern agriculture tends towards agroecological control of harmful insects.But this requires the development of new, suitable alternative techniques. Since the beginning of the 19th century, the world population has been constantly increasing, rising from 7.5 billion people in 2017 to a forecast of around 11 billion by the end of the 21st century. Given the problems of undernutrition and malnutrition encountered throughout the world, agriculture must face a significant challenge: producing food resources in sufficient quantity and quality. Indeed, many pests and diseases that cause considerable damage to plants can lead to quantitative losses and / or qualitative changes in the harvest. Among these pests and diseases, insect pests cause between 20 and 40% of agricultural production losses each year. The reduction in the number of authorized active substances makes the fight against harmful insects increasingly difficult.In addition, the unsustainable use of insecticides has led to the emergence of insecticide-resistant insect pests. Inventors have been particularly interested in developing a strategy to combat insect pests such as, for example, the pea aphid Acyrthosiphon pisum and the cockroach Periplaneta americana. The pea aphid colonizes many cultivated legumes such as peas, beans, broad beans, lentils, and alfalfa. Legume cultivation ranks second in global production after cereals, representing approximately 13% of cultivated areas (Gepts et al., 2005). It causes direct damage due to sap extraction but is also capable of transmitting numerous viruses. To date, 30 viruses transmitted by the pea aphid have been identified: bean mosaic virus, cucumber mosaic virus, etc.Neonicotinoids are the insecticides that have been most widely used in agriculture over the past ten years. Although a temporary authorization for use was granted by the law of December 14, 2020 to protect sugar beet crops threatened by massive aphid infestations against which current insecticide treatments are not effective, the use of these neonicotinoids has been prohibited since 2018. Consequently, few chemical substances currently remain usable to control harmful insects, including crop pests, and more particularly aphids, which makes it difficult to control these insects that are adapted or even resistant to these chemical insecticide treatments.Brief description of the invention The inventors propose a new strategy for controlling harmful insects based on the use of interfering RNA (RNAi) targeting the cholinergic system as bioinsecticides or as agents that synergize the effect of the insecticide used at low doses. Indeed, the cholinergic system in insects plays a major role in their physiology. Given this important physiological role of acetylcholine (ACh) in insects, the cholinergic system constitutes a preferred target for many families of insecticides such as carbamates and organophosphates which inhibit the activity of the ACh degrading enzyme, acetylcholinesterase; spinosyns, neonicotinoids, butenolides, sulfoximines and mesoionics targeting nicotinic cholinergic receptors (nAChR).Until 2018, the use of neonicotinoids was the most effective way to control insect pests in crops. These insecticides were widely used in agriculture for plant protection, as phytosanitary products, and by individuals or businesses to control insects harmful to human and animal health, as biocidal products. Article 125 of the law of August 8, 2016, known as the "law for the recovery of biodiversity, nature and landscapes," prohibits "the use of plant protection products containing one or more active substances from the neonicotinoid family and seeds treated with these products […] as of 1. erSeptember 2018", with possible exemptions. Since the ban on the use of neonicotinoids, neurotoxic chemical control has been mainly based on the use of pyrethroids. However, the lower effectiveness of this class of insecticide on harmful insects led to a temporary authorization for the use of neonicotinoids by the law of December 14, 2020 for sugar beets, while other solutions are found to protect these crops massively threatened by aphids. Other known means of controlling aphids include the use of beneficial insects such as Coccinella septempunctata and parasitoids such as Aphidius avenae, mechanical control with the installation of anti-insect nets or trapping with the use of sticky panels.The present invention is based on the use of the RNA interference technique which is a species-specific method (Whyard et al., 2009), which has made it possible to develop a new specific strategy for controlling harmful insect species, for example the pea aphid Acyrthosiphon pisum, without affecting beneficial insects such as the honeybee Apis mellifera. Toxicity tests were also carried out by the company Testapi at the request of the inventors to evaluate the acute oral toxicity and contact toxicity on Apis mellifera L. bees of the dsRNA preparation of the β2 subunit of the nicotinic receptor of Acyrthosiphon pisum.The study did not reveal any toxicity of the preparation of the invention towards bees and the study is considered valid considering that the mortality of the control population was within the acceptable range and that the reference toxicant (dimethoate) produced the typical effects in the validated phases. The RNA interference technique allows to specifically regulate the expression of a protein. Once in the cell, double-stranded interfering RNAs (dsRNA or dsRNA) are cleaved into small interfering RNAs of 21 to 25 nucleotides (siRNA or siRNA) by an RNAse III called DICER. This ribonuclease then transfers the siRNAs to the multi-enzyme complex RISC (RNA-induced silencing complex). While the sense strand of the siRNA called "passenger" is eliminated, the antisense "guide" strand, complementary to the mRNA of the gene of interest, directs the RISC complex towards the target mRNAs in order to degrade them, thus preventing their translation.The present invention targets the cholinergic system of the harmful insect and more precisely the neuronal nicotinic subunits forming the nicotinic receptors (nAChRs) and their auxiliary proteins. The nAChRs, which are the targets of many insecticides, are part of transmembrane complexes that are located at synapses and allow the rapid transmission of nervous information when activated by the binding of ACh. They are pentameric glycoprotein complexes belonging to the "Cys-loop" family which includes different ionotropic receptors called "Ligand-Gated Ion Channel" (LGIC) and are permeable to different cations (Na. + , That 2+ and K +). These nAChRs composed of 5 subunits can be homomeric (5 identical α subunits) or heteromeric (5 different α or β subunits). To date, analysis of the genome of different insects has made it possible to identify several nicotinic subunits: 10 α subunits ranging from α1 to α10 and 10 β subunits ranging from β1 to β10, plus their isoforms (Jones et al., 2021; Dale et al., 2010). The α subunits are differentiated from the β subunits by the presence of 2 adjacent cysteines in the amino-terminal part. The nicotinic subunit composition of nAChRs makes it possible to define their electrophysiological and pharmacological properties, as well as their sensitivity to insecticides. For example, sequencing of the A. pisum genome (International Aphid Genomics Consortium, 2010) allowed the identification of 11 genes coding for nicotinic subunits (Dale et al., 2010).Among these, the α9, α10 and β2 subunits are so-called "divergent" subunits, meaning they have little sequence homology with known nicotinic subunits in other insect species. The inventors used the RNA interference technique to target one of these subunits, the Apisum β2 subunit, also called β2. Further development was necessary to determine the mode of application of the interfering RNAs (dsRNA). Thus, a topical application of 400 ng of dsRNA per aphid was used in the experiments. After demonstrating that this interfering RNA did indeed cause a reduction in the number of transcripts coding for β2, the inventors demonstrated that aphids that received these dsRNAs topically showed an increase in the mortality rate of approximately 6%, 31% and 51% at 24 hours, 48 ​​hours and 72 hours respectively after application.Given that the nicotinic subunit composition of nAChRs determines their sensitivity to insecticides, the decrease in β2 subunit mRNA expression by specific dsRNAs observed in pea aphids suggests a change in nAChR composition leading to modulation of the efficacy of insecticide treatment. Experimental results show that adult aphids that absorbed dsRNA against the β2 subunit and were then intoxicated with imidacloprid at a concentration close to the LC. 50 , namely 5.10 -3µg / mL, have a slightly increased mortality (1.4 times) 72 hours after acute poisoning, compared to control aphids. Thus, the use of specific dsRNAs inducing a modification of the composition of nAChRs would make the insects more sensitive to the insecticide. This synergistic effect is detailed below in the examples. Detailed description of the invention The present invention relates to a method for controlling harmful insects by inhibiting the translation of the mRNA of a target gene belonging to the cholinergic system of the insect induced by RNA interference. The term "harmful insect" means any insect exhibiting an activity having effects considered to be detrimental to public health and / or the proper conduct of certain human activities such as agriculture or livestock farming. Harmful insects include phytophagous, saprophagous and detritiphagous insects, predatory, parasitic and commensal insects,hematophagous. Phytophagous insects include Helicoverpa armigera, Bemisia tabaci, Plutella xylostella, Tribolium castaneum, Myzus persicae, Spodoptera frugiperda, Aphis gossypii, Nilaparvata lugens, Spodoptera exigua, Ceratitis capitata, Cydia pomonella, Acyrthosiphon pisum, Diaphorina citri, and Thrips tabaci. The term "cholinergic system" includes cholinergic receptors capable of binding acetylcholine, as well as their ligands. Here, we are only interested in nicotinic receptors, not muscarinic receptors. "RNA interference" is understood to mean the technique that allows the specific regulation of protein expression by inhibiting the translation of mRNA. The mechanism already discussed above will be detailed below. In a particular embodiment,the method may comprise the steps of: - preparing a double-stranded RNA specific for a target mRNA; - administering the double-stranded RNA to at least one pest insect in an amount effective to induce mortality or insecticide sensitivity of the targeted insect. In an alternative particular embodiment, the method may comprise the steps of: - preparing a single-stranded antisense oligonucleotide (ASO) specific for a target mRNA; - administering the single-stranded antisense oligonucleotide to at least one pest insect in an amount effective to induce mortality or insecticide sensitivity of the targeted insect. Antisense oligonucleotides are small, single-stranded nucleic acids (RNA or DNA) that have the ability to associate to form heteroduplexes with the target mRNA,inhibiting its function by impairing the translation of mRNA into protein or by causing the destruction of mRNA by recruiting RNAse H which hydrolyzes RNA in the RNA / DNA duplex. Their operation differs depending on the type of oligonucleotide used for gene silencing. In a particular embodiment, the target mRNA may be selected from the group comprising mRNAs of the neuronal α subunit group of the nicotinic receptor, mRNAs of the neuronal β subunit group of the nicotinic receptor, mRNAs encoding auxiliary proteins and molecules, and their isoforms, and a protein of the nicotinic receptor interactome. Known auxiliary proteins and molecules of the nicotinic receptor are, for example, NACHO, Lynx, TMX-3, RIC-3,UNC-50 and their isoforms. NACHO (novel nAChR regulator) and RIC-3 (resistance to inhibitor of cholinesterase 3) are transmembrane chaperone proteins responsible for the folding and assembly of nAChRs in the endoplasmic reticulum. RIC-3 also appears to be necessary for targeting nAChRs to the plasma membrane. Lynx (Ly-6 / neurotoxin protein) is an extracellular protein, anchored to the plasma membrane via glycosylphosphatidylinositol (GPI), which decreases the sensitivity of nAChRs to acetylcholine. UNC-50 (inner nuclear membrane RNA binding protein) is a protein located in the Golgi apparatus that regulates nAChR biosynthesis and targeting to the plasma membrane. The term "interactome" refers to all the molecular interactions that occur with the nicotinic receptor within a cell, tissue or organism, during various physiological processes. Furthermore,herein, the term "effective amount" for inducing mortality or sensitivity to an insecticide of the targeted insect means an amount allowing an increase in mortality of at least 10% compared to the absence of treatment or an improvement in sensitivity of at least 10% compared to treatment with the insecticide alone. This effective amount depends both on the effectiveness of each double-stranded RNA or antisense oligonucleotide, the time of functionality thereof, the type of administration and the targeted insect. In a particular embodiment, the target mRNA may be at least one chosen from the mRNAs of the neuronal subunits α1 to α10 of the nicotinic receptor and the mRNAs of the neuronal subunits β1 to β10 of the nicotinic receptor. In an exemplary embodiment, the target mRNA may be selected from the group consisting of Acyrthosiphon pisum neuronal nicotinic receptor α subunit group mRNAs,namely the mRNAs encoding the neuronal α1 subunit of the nicotinic receptor (SEQ ID NO: 1, accession no.: XM_008182407.3), the mRNAs encoding the neuronal α2 subunit of the nicotinic receptor (SEQ ID NO: 2, accession no.: XM_008182417.3), the mRNAs encoding the neuronal α3 subunit of the nicotinic receptor (SEQ ID NO: 3, accession no.: XM_008187942.3), the mRNAs encoding the isoforms of the neuronal α4 subunit of the nicotinic receptor (SEQ ID NO: 4, accession no.: XM_029490651.1; SEQ ID NO: 5, accession no.: XM_029490650.1), the mRNA encoding isoforms of the neuronal α6 subunit of the nicotinic receptor (SEQ ID NO: 6, accession no.: XM_016809607.2; SEQ ID NO: 7, accession no.: XM_016809606.2), mRNA encoding isoforms of the neuronal α7 subunit of the nicotinic receptor (SEQ ID NO: 8, accession no.: XM_001945189.5; SEQ ID NO: 9, accession no.: XM_029490468.1; SEQ ID NO: 10, accession no.: XM_008187756.3; SEQ ID NO: 11,accession number: XM_016806826.2; SEQ ID NO: 12, accession number: XM_029490467.1; SEQ ID NO: 13, accession no.: XM_016806827.2), mRNAs encoding the neuronal α8 subunit of the nicotinic receptor (SEQ ID NO: 14, accession no.: XM_001949983.5), mRNAs encoding the neuronal α9 subunit of the nicotinic receptor (SEQ ID NO: 15, accession no.: XM_016807628.1), mRNAs encoding the neuronal α10 subunit of the nicotinic receptor (SEQ ID NO: 16, accession no.: XM_016807463.2), and their isoforms. In another exemplary embodiment, the target mRNA may be selected from the group consisting of Acyrthosiphon pisum neuronal nicotinic receptor β subunit group mRNAs, namely mRNAs encoding the neuronal nicotinic receptor β1 subunit (SEQ ID NO: 17, Accession No: XM_029487953.1) and mRNAs encoding the neuronal nicotinic receptor β2 subunit (SEQ ID NO: 18, Accession No: XM_001945029.5),and their isoforms. In yet another exemplary embodiment, the target mRNA may be selected from the group consisting of mRNAs of the auxiliary protein isoforms RIC-3 (RIC-3 A, SEQ ID NO: 70, Accession No.: XM_008186459.3; RIC-3 B, SEQ ID NO: 71, Accession No.: XM_008186458.3, RIC-3 C, SEQ ID NO: 72, Accession No.: XM_008186457.3), Lynx (Lynx 1, SEQ ID NO: 73, Accession No.: NM_001162709.1; Lynx 4, SEQ ID NO: 74, Accession No.: XM_001945238.5; Lynx 5, SEQ ID NO: 75, Accession No.: XM_001950961.5; Lynx 6, SEQ ID NO: 76, accession no: NM_001162627.2; Lynx 10C, SEQ ID NO: 77, accession no: NM_001162777.2), NACHO (SEQ ID NO: 78, accession no: NM_001205021.1), UNC-50 (SEQ ID NO: 79, accession no: NM_001162643.2) and TMX-3 (SEQ ID NO: 80, accession no: XM_008188638.3) from Acyrthosiphon pisum. Preferably,the target mRNA can be selected from the mRNAs of the auxiliary proteins Lynx6 and NACHO of Acyrthosiphon pisum. The protein sequences of these isoforms of the auxiliary proteins of Acyrthosiphon pisum are as follows: RIC-3 (RIC-3 A, SEQ ID NO: 81, accession no.: XP_008184681.1; RIC-3 B, SEQ ID NO: 82, accession no.: XP_008184680.1, RIC-3 C, SEQ ID NO: 83, accession no.: XP_008184679.1), Lynx (Lynx 1, SEQ ID NO: 84, accession no.: NP_001156181.1; Lynx 4, SEQ ID NO: 85, accession no.: XP_001945273.1; Lynx 5, SEQ ID NO: 86, accession no.: XP_001950996.2; Lynx 6, SEQ ID NO: 87, Accession No: NP_001156099.1; Lynx 10C, SEQ ID NO: 88, Accession No: NP_001156249.1), NACHO (SEQ ID NO: 89, Accession No: NP_001191950.1), UNC-50 (SEQ ID NO: 90, Accession No: NP_001156115.1) and TMX-3 (SEQ ID NO: 91, Accession No: XP_008186860.1). In an exemplary embodiment,the target mRNA may be selected from the group consisting of mRNAs of the neuronal α subunit group of the nicotinic receptor of Periplaneta americana, namely mRNAs encoding the neuronal α1 subunit of the nicotinic receptor (SEQ ID NO: 19, Accession No: KP725463.1), mRNAs encoding the neuronal α2 subunit of the nicotinic receptor (SEQ ID NO: 20, Accession No: KP725464.1), mRNAs encoding the neuronal α3 subunit of the nicotinic receptor (SEQ ID NO: 21, Accession No: KR021292.1), mRNAs encoding the isoforms of the neuronal α4 subunit of the nicotinic receptor (SEQ ID NO: 22, Accession No: JN390946.1; SEQ ID NO: 23, Accession No: JN390945.1), mRNAs encoding the neuronal α5 subunit of the nicotinic receptor (SEQ ID NO: 24, Accession No: GFCQ01005211.1), mRNAs encoding the isoforms of the neuronal α6 subunit of the nicotinic receptor (SEQ ID NO: 25, Accession No: JF731243.1; SEQ ID NO: 26,accession number: JX466887.1; SEQ ID NO: 27, accession no: JX466888.1; SEQ ID NO: 28, accession no: JX466889.1; SEQ ID NO: 29, Accession No: JX466890.1), mRNAs encoding isoforms of the neuronal α7 subunit of the nicotinic receptor (SEQ ID NO: 30, Accession No: MW201211.1; SEQ ID NO: 31, Accession No: JF731242.1; SEQ ID NO: 32, Accession No: MK790056.1; SEQ ID NO: 33, Accession No: JX466891.1), mRNAs encoding the neuronal α8 subunit of the nicotinic receptor (SEQ ID NO: 34, Accession No: MW201212.1), mRNAs encoding the neuronal α9 subunit of the nicotinic receptor (SEQ ID NO: 35, Accession No: MW201214.1), and isoforms thereof. In another exemplary embodiment, the target mRNA may be selected from the group consisting of mRNAs of the neuronal β subunit group of the nicotinic receptor from Periplaneta americana, namely mRNAs encoding the neuronal β1 subunit of the nicotinic receptor (SEQ ID NO: 36,accession no.: MW201213.1), mRNAs encoding the neuronal β2 subunit of the nicotinic receptor (SEQ ID NO: 37, accession no.: GFCQ01032711.1), mRNAs encoding the neuronal β3 subunit of the nicotinic receptor (SEQ ID NO: 38, accession no.: GFCQ01027461.1), mRNAs encoding the neuronal β4 subunit of the nicotinic receptor (SEQ ID NO: 39, accession no.: GAWS02039241.1), mRNAs encoding the neuronal β5 subunit of the nicotinic receptor (SEQ ID NO: 40, accession no.: GFCQ01009686.1), mRNAs encoding the neuronal β6 subunit of the nicotinic receptor nicotinic receptor (SEQ ID NO: 41, accession no.: GFCQ01010089.1), mRNAs encoding the neuronal β7 subunit of the nicotinic receptor (SEQ ID NO: 42, accession no.: GFCQ01012153.1), mRNAs encoding the neuronal β8 subunit of the nicotinic receptor (SEQ ID NO: 43, accession no.: GFCQ01034959.1), mRNAs encoding the neuronal β9 subunit of the nicotinic receptor (SEQ ID NO: 44,accession no.: GBJC01015771.1), the mRNAs coding for the neuronal β10 subunit of the nicotinic receptor (SEQ ID NO: 45, accession no.: GFCQ01027794.1), and their isoforms. For this purpose, the double-stranded RNA or single-stranded antisense oligonucleotide can be administered by a topical administration method, by spraying, by vaporization, via nanoparticles such as lipid nanoparticles, chitosan, liposomes, niosomes, cationic dendrimers, lipoplexes, via food, by trapping in a bait box, by irrigation of crops. The administration is not limited to the methods provided above but the person skilled in the art will be able to include any other possible administration method from an agricultural, agri-food, health and / or environmental point of view. In one embodiment, the harmful insect may be at least one selected from phytophagous insects, saprophagous and detritiphagous insects, predatory insects,parasitic insects and commensal insects, hematophagous insects, especially among phytophagous insects, more particularly Helicoverpa armigera, Bemisia tabaci, Plutella xylostella, Tribolium castaneum, Myzus persicae, Spodoptera frugiperda, Aphis gossypii, Nilaparvata lugens, Spodoptera exigua, Ceratitis capitata, Cydia pomonella, Acyrthosiphon pisum, Diaphorina citri, Periplaneta americana or Thrips tabaci. In particular, the harmful insect is Acyrthosiphon pisum. The aphid is one of the most destructive insect pest species of crops to date. There are approximately 5000 species of aphids in the world, 100 of which are pests with a significant economic impact through the destruction of crops. The damage caused by these insects is due, on the one hand, to a significant offspring by aphids which can reproduce by parthenogenesis and, on the other hand,that these insects are piercing-sucking insects that feed on plant sap, causing possible growth retardation, discoloration, or deformation of plants, and that can transmit viruses. More specifically, the pea aphid A. pisum colonizes many cultivated legumes, which represent approximately 13% of cultivated areas worldwide. This aphid is responsible for hundreds of millions of dollars in losses each year. In another particular embodiment, the pest insect is Periplaneta americana. In a particular embodiment of the invention, the double-stranded RNA or antisense oligonucleotide may be administered by feeding at least one insect with a transgenic organism expressing the double-stranded RNA or antisense oligonucleotide. For this purpose, the transgenic organism may be a transgenic plant. Examples of transgenic plants include legumes, such as peas, beans,chickpeas, lentils, broad beans, field beans, soybeans, alfalfa, lupin, sainfoin, trefoil, clovers or vetch, cereals such as wheat, corn, sorghum, rye, barley, oats or rice, but also fruit and vegetable plants. The invention also relates to an insecticidal composition for harmful insects, the composition comprising a double-stranded RNA or an antisense oligonucleotide and at least one of a transfection agent and a solvent, wherein said double-stranded RNA or antisense oligonucleotide comprises a nucleotide sequence which is at least 90% identical with at least a portion of the sequence of a target mRNA, the target mRNA being selected from the group consisting of the coding sequences of the genes of the neuronal α subunit group of the nicotinic receptor, the genes of the neuronal β subunit group of the nicotinic receptor, and their isoforms,the nucleotide sequences of the genes coding for the proteins and auxiliary molecules of the nicotinic receptor, and their isoforms, or for a protein of the interactome of the nicotinic receptor. The composition of the invention is intended to be administered by a topical administration method, by spraying, by vaporization, by means of nanoparticles of the lipid nanoparticle, chitosan, liposomes, niosomes, cationic dendrimers, lipoplexes type, by food, by trapping in a bait box, by irrigation of crops. The administration is not limited to the methods provided above but a person skilled in the art will be able to include any other possible administration method from an agricultural, agri-food, health and / or environmental point of view. In an exemplary embodiment, the invention relates to an insecticidal composition comprising a double-stranded RNA or antisense oligonucleotide and a transfection agent or a solvent,wherein said double-stranded RNA or antisense oligonucleotide comprises a nucleotide sequence which is at least 90% identical with at least a portion of the sequence of the target mRNA, the target mRNA being selected from the group consisting of the coding sequences of the genes of the neuronal α subunit group of the nicotinic receptor of Acyrthosiphon pisum, namely the mRNAs encoding the neuronal α1 subunit of the nicotinic receptor (SEQ ID NO: 1), the mRNAs encoding the neuronal α2 subunit of the nicotinic receptor (SEQ ID NO: 2), the mRNAs encoding the neuronal α3 subunit of the nicotinic receptor (SEQ ID NO: 3), the mRNAs encoding the isoforms of the neuronal α4 subunit of the nicotinic receptor (SEQ ID NO: 4; SEQ ID NO: 5), the mRNAs encoding the isoforms of the neuronal α6 subunit of the nicotinic receptor (SEQ ID NO: 6; SEQ ID NO: 7),mRNAs encoding isoforms of the neuronal α7 subunit of the nicotinic receptor (SEQ ID NO: 8; SEQ ID NO: 9; SEQ ID NO: 10; SEQ ID NO: 11; SEQ ID NO: 12; SEQ ID NO: 13), mRNAs encoding the neuronal α8 subunit of the nicotinic receptor (SEQ ID NO: 14), mRNAs encoding the neuronal α9 subunit of the nicotinic receptor (SEQ ID NO: 15), mRNAs encoding the neuronal α10 subunit of the nicotinic receptor (SEQ ID NO: 16), and isoforms thereof, and in the group consisting of the coding sequences of genes of the neuronal β subunit group of the nicotinic receptor of Acyrthosiphon pisum, namely mRNAs encoding the neuronal subunit β1 nicotinic receptor (SEQ ID NO: 17) and mRNAs encoding the neuronal β2 nicotinic receptor subunit (SEQ ID NO: 18), and isoforms thereof. In yet another exemplary embodiment,the target mRNA may be selected from the group consisting of mRNAs of the auxiliary protein isoforms RIC-3 (RIC-3 A, SEQ ID NO: 70, accession no.: XM_008186459.3; RIC-3 B, SEQ ID NO: 71, accession no.: XM_008186458.3, RIC-3 C, SEQ ID NO: 72, accession no.: XM_008186457.3), Lynx (Lynx 1, SEQ ID NO: 73, accession no.: NM_001162709.1; Lynx 4, SEQ ID NO: 74, accession no.: XM_001945238.5; Lynx 5, SEQ ID NO: 75, accession no.: XM_001950961.5; Lynx 6, SEQ ID NO: 76, accession no.: NM_001162627.2; Lynx 10C, SEQ ID NO: 77, accession no.: NM_001162777.2), NACHO (SEQ ID NO: 78, accession no.: NM_001205021.1), UNC-50 (SEQ ID NO: 79, accession no.: NM_001162643.2) and TMX-3 (SEQ ID NO: 80, accession no.: XM_008188638.3) of Acyrthosiphon pisum. Preferably, the target mRNA may be selected from the mRNAs of the auxiliary proteins Lynx6 and NACHO of Acyrthosiphon pisum. In a particular embodiment, the transfection-promoting agent may comprise,but not limited to, a lipid compound, a liposome, a niosome, a lipid nanoparticle, a dendrimer, an insect virus. It is understood that those skilled in the art will be able to adapt the transfection mode depending on the context and the need. RNA transfection techniques are widely described in the scientific literature. In a particular embodiment, the composition may further comprise one or more agents selected from a synergistic agent, a repellent agent and an attractive agent. The synergistic agent (or synergizing agent) may, for example,be piperonyl butoxide (PBO) which is a detoxification enzyme inhibitor. Its action is to slow down the breakdown of toxic chemicals in insects and this mechanism allows the pesticide to be maintained in its toxic form for longer periods of time. The term "repellent agent" means a natural or synthetic chemical substance used to repel the harmful insect of interest, in particular to protect agricultural crops or harvests. The term "attractive agent" means a natural or synthetic chemical substance used to attract the harmful insect of interest, in particular to bait it or attract it to a trap. In a particular embodiment, the composition may further comprise a carrier acceptable from an agricultural, agri-food,health and / or environmental. Such a support refers to a non-toxic material that does not interfere with the effectiveness of the biological activity of the composition and that is compatible with a biological system such as a cell, a cell culture, a tissue or an organism. In a particular embodiment, the composition is formulated as a bait for the harmful insect(s). For this purpose, the composition may comprise an attractant intended to attract the insect to a bait box to trap it therein. The invention also relates to a plant cell, a plant tissue or a transgenic plant comprising at least one nucleic acid that is transcribed to produce a double-stranded RNA, in which the double-stranded RNA comprises a nucleotide sequence having at least 90% identity with at least a portion of the sequence of a target mRNA,the target mRNA being selected from the group consisting of the coding sequences of genes of the neuronal α subunit group of the nicotinic receptor, the coding sequences of genes of the neuronal β subunit group of the nicotinic receptor, and their isoforms, the nucleotide sequences of genes encoding proteins and auxiliary molecules of the nicotinic receptor, and their isoforms, or for a protein of the nicotinic receptor interactome. In an exemplary embodiment, the invention relates to a plant cell, a plant tissue or a transgenic plant comprising one or more nucleic acids which is or are transcribed to produce a double-stranded RNA, wherein said double-stranded RNA comprises a nucleotide sequence which is at least 90% identical with at least a portion of the sequence of the target mRNA,the target mRNA being selected from the group consisting of the coding sequences of the genes of the neuronal α subunit group of the nicotinic receptor of Acyrthosiphon pisum, namely the mRNAs coding for the neuronal α1 subunit of the nicotinic receptor (SEQ ID NO: 1), the mRNAs coding for the neuronal α2 subunit of the nicotinic receptor (SEQ ID NO: 2), the mRNAs coding for the neuronal α3 subunit of the nicotinic receptor (SEQ ID NO: 3), the mRNAs coding for the isoforms of the neuronal α4 subunit of the nicotinic receptor (SEQ ID NO: 4; SEQ ID NO: 5), the mRNAs coding for the isoforms of the neuronal α6 subunit of the nicotinic receptor (SEQ ID NO: 6; SEQ ID NO: 7), the mRNAs coding for the isoforms of the neuronal α7 subunit of the nicotinic receptor (SEQ ID NO: 8; SEQ ID NO: 9; SEQ ID NO: 10; SEQ ID NO: 11; SEQ ID NO: 12; SEQ ID NO: 13), mRNAs encoding the neuronal α8 subunit of the nicotinic receptor (SEQ ID NO: 14),the mRNAs encoding the neuronal α9 subunit of the nicotinic receptor (SEQ ID NO: 15), the mRNAs encoding the neuronal α10 subunit of the nicotinic receptor (SEQ ID NO: 16), and their isoforms, and in the group consisting of the coding sequences of the genes of the neuronal β subunit group of the nicotinic receptor of Acyrthosiphon pisum, namely the mRNAs encoding the neuronal β1 subunit of the nicotinic receptor (SEQ ID NO: 17) and the mRNAs encoding the neuronal β2 subunit of the nicotinic receptor (SEQ ID NO: 18), and their isoforms. In yet another exemplary embodiment, the target mRNA may be selected from the group consisting of mRNAs of the auxiliary protein isoforms RIC-3 (RIC-3 A, SEQ ID NO: 70, Accession No.: XM_008186459.3; RIC-3 B, SEQ ID NO: 71, Accession No.: XM_008186458.3, RIC-3 C, SEQ ID NO: 72, Accession No.: XM_008186457.3), Lynx (Lynx 1, SEQ ID NO: 73, Accession No.: NM_001162709.1; Lynx 4, SEQ ID NO: 74,accession number: XM_001945238.5; Lynx 5, SEQ ID NO: 75, accession number: XM_001950961.5; Lynx 6, SEQ ID NO: 76, accession number: NM_001162627.2; Lynx 10C, SEQ ID NO: 77, accession no.: NM_001162777.2), NACHO (SEQ ID NO: 78, accession no.: NM_001205021.1), UNC-50 (SEQ ID NO: 79, accession no.: NM_001162643.2) and TMX-3 (SEQ ID NO: 80, accession number: XM_008188638.3) of Acyrthosiphon pisum. Preferably, the target mRNA may be selected from the mRNAs of the auxiliary proteins Lynx6 and NACHO of Acyrthosiphon pisum. For this purpose, the double-stranded RNA is at least 20 base pairs in length, in particular 20-2000 base pairs in length, preferably 20-900 base pairs in length. The interfering RNA may inhibit the translation of mRNAs corresponding to the coding sequence of any of the genes of the neuronal α subunit group of the nicotinic receptor, the genes of the neuronal β subunit group of the nicotinic receptor, and their isoforms,to any of the nucleotide sequences of the genes encoding nicotinic receptor proteins and auxiliary molecules, and their isoforms, or to the DNA sequence encoding a protein of the nicotinic receptor interactome. The antisense oligonucleotide can inhibit the translation of mRNAs corresponding to the coding sequence of any of the genes of the neuronal α subunit group of the nicotinic receptor, the genes of the neuronal β subunit group of the nicotinic receptor, and their isoforms, to any of the nucleotide sequences of the genes encoding nicotinic receptor proteins and auxiliary molecules, and their isoforms, or to the DNA sequence encoding a protein of the nicotinic receptor interactome. In an exemplary embodiment,the antisense dsRNA or oligonucleotide can inhibit the translation of mRNA corresponding to the coding sequence of any of the genes of the neuronal α subunit group of the nicotinic receptor of Acyrthosiphon pisum, namely mRNAs encoding the neuronal α1 subunit of the nicotinic receptor (SEQ ID NO: 1), mRNAs encoding the neuronal α2 subunit of the nicotinic receptor (SEQ ID NO: 2), mRNAs encoding the neuronal α3 subunit of the nicotinic receptor (SEQ ID NO: 3), mRNAs encoding the isoforms of the neuronal α4 subunit of the nicotinic receptor (SEQ ID NO: 4; SEQ ID NO: 5), mRNAs encoding the isoforms of the neuronal α6 subunit of the nicotinic receptor (SEQ ID NO: 6; SEQ ID NO: 7), mRNAs encoding isoforms of the neuronal α7 subunit of the nicotinic receptor (SEQ ID NO: 8; SEQ ID NO: 9; SEQ ID NO: 10; SEQ ID NO: 11; SEQ ID NO: 12; SEQ ID NO: 13),mRNAs encoding the neuronal α8 subunit of the nicotinic receptor (SEQ ID NO: 14), mRNAs encoding the neuronal α9 subunit of the nicotinic receptor (SEQ ID NO: 15), mRNAs encoding the neuronal α10 subunit of the nicotinic receptor (SEQ ID NO: 16), and isoforms thereof, and any of the genes in the neuronal β subunit cluster of the nicotinic receptor of Acyrthosiphon pisum, namely mRNAs encoding the neuronal β1 subunit of the nicotinic receptor (SEQ ID NO: 17) and mRNAs encoding the neuronal β2 subunit of the nicotinic receptor (SEQ ID NO: 18), and isoforms thereof. In yet another exemplary embodiment, the dsRNA or antisense oligonucleotide can inhibit translation of mRNA corresponding to the coding sequence of any of the genes in the RIC-3 auxiliary protein isoform group (RIC-3 A, SEQ ID NO: 70, Accession No: XM_008186459.3; RIC-3 B, SEQ ID NO: 71, Accession No: XM_008186458.3,RIC-3 C, SEQ ID NO : 72, n° accession : XM_008186457.3), Lynx (Lynx 1, SEQ ID NO : 73, n° accession : NM_001162709.1 ; Lynx 4, SEQ ID NO : 74, n° accession : XM_001945238.5 ; Lynx 5, SEQ ID NO : 75, n° accession : XM_001950961.5 ; Lynx 6, SEQ ID NO : 76, n° accession : NM_001162627.2 ; Lynx 10C, SEQ ID NO : 7, n°accession : NM_001162777.2), NACHO (SEQ ID NO : 78, n° accession : NM_001205021.1), UNC-50 (SEQ ID NO : 79, n° accession : NM_001162643.2) et TMX-3 (SEQ ID NO : 80, n° accession : XM_008188638.3) de Acyrthosiphon pisum. De manière préférée,the target mRNA may be selected from the mRNAs of the Lynx6 and NACHO auxiliary proteins of Acyrthosiphon pisum. The invention also relates to the use of interfering RNA or antisense oligonucleotide as a bioinsecticide. The term "bioinsecticide" or "biological insecticide" means a form of insecticide based on microorganisms or natural products. These bioinsecticides are biological or biologically derived agents allowing the management of harmful insects in a more environmentally friendly manner. In another embodiment,The invention relates to the use of interfering RNA or antisense oligonucleotide as a synergizing agent for the insecticidal effect of an insecticide or a molecule with an insecticidal effect against a harmful insect. The term "synergizing agents for the insecticidal effect" means molecules that make it possible to increase the effect of the insecticide by, for example, increasing sensitivity to it while reducing the concentration necessary for its action. Examples of synergizing agents in this context include, in particular, chemical molecules or microorganisms, such as insect viruses. The expression "molecule with an insecticidal effect against a harmful insect" is intended to describe complex natural substances such as essential oils or pheromones. Examples of such substances include, in particular, essential oil of spike lavender, essential oil of geranium, essential oil of citronella, essential oil of eucalyptus,peppermint essential oil, cryptomeria essential oil, thyme essential oil. In addition, the insecticide may include, but is not limited to, neonicotinoids, in particular imidacloprid, clothianidin, acetamiprid, dinotefuran, nitenpyram, thiacloprid and thiamethoxam, spinosyns, butenolides, mesoionics, sulfoximines, carbamates, pyrethroids, oxadiazines and organophosphates or the molecule with an insecticidal effect may include, but is not limited to, a natural substance, an essential oil, a pheromone. In another embodiment, the invention relates to the use of interfering RNA or antisense oligonucleotide as an agent for restoring the sensitivity of a harmful insect to an insecticide. For this purpose,the interfering RNA or antisense oligonucleotide of interest makes it possible to restore sensitivity to an insecticide that may have been lost through excessive and / or incorrect exposure to the insecticide. Many mechanisms, both biochemical and physiological, or even behavioral, are developed by insects to try to escape the toxicity of insecticides. This aspect is interesting and the experimental results obtained by the inventors suggest a particularly innovative use of interfering RNA or antisense oligonucleotides to overcome resistance to insecticides. To better illustrate the subject of the present invention, the following examples will now be described below, by way of illustration and not limitation, in conjunction with the accompanying drawings. In these drawings: [Fig. 1] is a histogram representing the quantification by qPCR of the expression of the transcripts of the nicotinic β2 subunit in the aphid A. pisum at 2 hours,24h and 72h post-absorption of dsRNA (β2 or LacZ). Relative expression is normalized with the RPL7 gene (reference gene) according to the 2 method, -∆∆Ct (*p<0.05 β2 vs LacZ for each time point, Mann-Whitney test, n=5 to 7). [Fig. 2] is a histogram representing the percentage of corrected mortality of aphids 24h, 48h and 72h after uptake of LacZ or β2 dsRNA (**p<0.01 vs LacZ, Mann-Whitney test, n=5 including 15 to 30 aphids per condition). [Fig. 3] is a graphical representation of the effect-concentration curve of the percentage of corrected mortality observed in aphid larvae as a function of imidacloprid concentration at 48h (A) and 72h (B) (n=5 including 20 aphid larvae per concentration). [Fig. 4] is a histogram representing the percentage of corrected mortality of aphids having absorbed dsRNA (LacZ or β2) 72h post-intoxication by imidacloprid (5.10 -3µg / mL). DMSO is the solvent of imidacloprid serving as a control (**p<0.01 vs LacZ, Mann-Whitney test n=3 to 5 including 15 to 30 aphids per n and per condition). [Fig. 5A] is a histogram representing the quantification by qPCR of the expression of nicotinic subunit mRNAs in the aphid A. pisum at 2h post-absorption of β2 or LacZ dsRNAs. The relative expression is normalized by the RPL7 gene (reference gene) according to the 2 method -∆∆Ctand the results are expressed as a ratio with the control condition (dsRNA LacZ, corresponding with the value bar 1) (*p<0.05 β2 vs LacZ, **p<0.01, Mann-Whitney test). [Fig. 5B] is a histogram representing the quantification by qPCR of the expression of nicotinic subunit mRNAs in the aphid A. pisum at 24h post-absorption of dsRNA β2 or LacZ. [Fig. 5C] is a histogram representing the quantification by qPCR of the expression of nicotinic subunit mRNAs in the aphid A. pisum at 72h post-absorption of dsRNA β2 or LacZ. [Fig. 6] is a graphical representation of the qPCR quantification of the expression of nicotinic β1 subunit transcripts in the DGA (last abdominal ganglion) from P. americana cockroaches that ingested dsRNA (LacZ, β1-start, β1-end, and β1-start+end mix). The relative expression is normalized with the actin gene (reference gene) according to the 2- method ∆∆Ct(*p<0.05 vs LacZ, Mann-Whitney test, n=4 to 8). [Fig. 7A] is a histogram representing the percentage of corrected mortality 96h after acute imidacloprid intoxication of cockroaches exposed (IMI J30) and not exposed (NE) to the sublethal dose of imidacloprid for 30 days. [Fig. 7B] is a histogram representing the percentage of corrected mortality 96h after acute imidacloprid intoxication of cockroaches exposed to the sublethal dose of imidacloprid for 30 days having ingested dsRNA (LacZ, β1-end or β1-beginning+end) or not (IMI J30). (n=1 including 8 to 9 cockroaches per condition). [Fig. [8A] is a graphical representation of the qPCR quantification of the expression of the nicotinic β2 subunit mRNA in the A. pisum aphid larva at 2h, 24h, 48h and 72h after their contact with a nutrient solution containing dsRNA (dsRNA-LacZ or dsRNA-β2) at 200ng / µL. The relative expression is normalized with the RPL7 gene (reference gene) according to the 2-∆∆Ct (*p<0.05, dsRNA-β2 vs dsRNA-LacZ, non-parametric Mann-Whitney test; n = 5 to 6 with 10 larvae per n). [Fig. [Fig. 8B] is a histogram representing the percentage mortality corrected compared to the control (dsRNA-LacZ) obtained according to the Henderson-Tilton formula in A. pisum aphid larvae having ingested dsRNA-β2 or dsRNA-LacZ (*p<0.05, **p<0.01; dsRNA-β2 vs dsRNA-LacZ, non-parametric Mann-Whitney test; n = 7 to 8 with 20 larvae per [Fig. 9] is a graphical representation of the qPCR quantification of the expression of transcripts of the isoforms of the auxiliary proteins RIC-3, Lynx, NACHO and UNC-50 in larvae (A) and adult A. pisum aphids (B). The relative expression is normalized with the RPL7 gene (reference gene) according to the 2 -∆∆Ct(n=6). Referring to Figure 1, it can be seen that the expression levels of mRNAs encoding the nicotinic β2 subunit in A. pisum aphids significantly decreased by 51%, 43% and 41% in aphids that absorbed β2 dsRNAs compared to control aphids that absorbed LacZ dsRNAs at 2h, 24h and 72h, respectively. This allows us to verify the effectiveness of dsRNAs on the expression of transcripts of the nicotinic β2 subunit of the pea aphid. Referring to Figure 2, it can be seen that the corrected mortality of aphids at 24h, 48h and 72h after topical application of dsRNAs is increased in aphids that have absorbed dsRNAs targeting the β2 subunit compared to control aphids (dsRNA LacZ) by approximately 6%, 31% and 51%, respectively. Referring to Figure 3, it can be seen that the imidacloprid concentration / effect on aphid mortality curves allow the estimation of the LC - 50 at 8.10 3µg / mL at 48h and 4.10 -3 µg / mL at 72h. For further experiments combining dsRNAs directed against the nicotinic β2 subunit and imidacloprid, the imidacloprid concentration of 5.10 -3 µg / mL is retained. In Figure 4, we can see that at 72h post-intoxication with imidacloprid at 5.10 -3µg / mL, the percentage of mortality increased by approximately 1.4 times in aphids that absorbed dsRNA targeting the β2 subunit (82%) compared to control aphids (LacZ, 60%). DMSO, the solvent for imidacloprid, served as a control. Referring to Figure 5A, the expression levels of mRNAs corresponding to the different nicotinic subunits identified in the genome of the aphid A. pisum were quantified by qPCR from cDNAs from aphids that absorbed dsRNA at different times post-administration. Figure 5A shows that 2 hours after administration of dsRNAs, a significant increase in the expression of mRNAs coding for subunits α1 to α8 is highlighted in aphids having absorbed the dsRNAs of interest compared to control aphids while the expression of subunits α9, α10 and β1 is not modified.Figure 5B shows that 24h post-administration of dsRNA, only the expression of the α9 subunit is affected by the decrease in the expression of the β2 subunit. Figure 5C shows that at 72h post-administration, the decrease in the expression of the β2 subunit does not seem to impact the expression of the other nicotinic subunits. In Figure 6, at 96h post-ingestion of dsRNA, we can note a decrease in the expression of the transcripts of the nicotinic β1 subunit of 20% in the DGA from cockroaches exposed to β1-end dsRNA and to the mixture of β1-start+end dsRNA. In contrast, β1 subunit mRNA expression does not appear to be affected by β1-start dsRNAs targeting the beginning of the β1 nucleotide sequence.Referring to Figure 7A, it can be seen that sublethal imidacloprid intoxication for 30 days induced a loss of sensitivity of cockroaches to this insecticide following re-exposure of cockroaches to an acute intoxication of 96 hours. Figure 7B shows that, unlike cockroaches ingesting LacZ dsRNAs, corrected mortality rates of 55% and 60% were observed 96 hours after acute imidacloprid intoxication in cockroaches ingesting β1-end+start and β1-end dsRNAs, respectively. These rates are similar to those obtained in cockroaches not exposed to the sublethal dose of imidacloprid for 30 days, which suggests that dsRNA, by modifying the expression of nAChRs, would make it possible to circumvent the resistance mechanisms put in place by the insect by restoring their sensitivity to the insecticide. EXAMPLES The following examples illustrate the invention.Example 1: Development of the RNA interference technique targeting the β2 nicotinic subunit in the pea aphid A. pisum as a means of controlling harmful insects For this species of harmful insect, the inventors focused on a divergent nicotinic subunit, the neuronal β2 subunit, in order to preserve non-target organisms. Materials and methods Study model: the aphid Acyrthosiphon pisum The pea aphids Acyrthosiphon pisum are reared at the SiFCIR laboratory on faba bean plants covered with a perforated cellophane bag and closed with an elastic band in an enclosure at a temperature of 20°C with a photoperiod of 16 hours of light and 8 hours of darkness. To ensure this rearing, 7 larvae reproducing by parthenogenesis are deposited on each faba bean plant every 10 days. On 21. èmeday, adult aphids are used for experiments. Extraction of total RNA Extraction of total RNA is carried out using the NucleoSpin® RNA kit (Macherey-Nagel) from adult aphids. To do this, each aphid is ground using an ultra-turrax® in 350µL of lysis buffer (RA1) supplemented with 3.5µL of β-mercaptoethanol and then the ground material is filtered. The nucleic acids contained in the lysate are then precipitated with 70% ethanol (350µL) and then fixed on a silica membrane. After DNase treatment and various membrane washes, the RNAs are eluted in 50µL of H2O. The quality and quantity of the RNAs obtained are evaluated by a spectrophotometric assay (SimpliNano). Reverse transcription cDNA synthesis from mRNA is performed using the RevertAid H Minus First strand cDNA Synthesis® kit (Thermoscientific).Thus, 500ng of total RNA (H2O qsp 11µL) are incubated at 65°C for 5 minutes with 1µL of oligo(dT)18 primers (0.5µg / µL) to allow hybridization of the primer to the poly(A) tail of the mRNAs. Then, an 8µL reaction mixture composed of 4µL of 5X reaction buffer, 1µL of RiboLock RNase Inhibitor (20U / µL), 2µL of dNTP (10mM) and 1µL of RevertAid H Minus M-MuLV Reverse Transcriptase enzyme (200U / µL) is added. Reverse transcription is carried out for 1h at 42°C and a final step of 5 minutes at 70°C to inactivate the reverse transcriptase is performed. Finally, the obtained cDNA samples are stored at -20°C. Amplification of the sequences of interest by PCR In order to obtain the coding sequence of the β2 subunit (NCBI accession no.: XM_001945029.5 – SEQ ID NO: 18) and the 140bp nucleotide fragment necessary for the synthesis of dsRNA targeting this subunit, PCR amplification is carried out from the cDNA of aphid A.pisum with KOD Hot Start™ high-fidelity polymerase (Novagen) using β2-ORF primers specific for the open reading frame and β2-dsRNA primers comprising the T7 promoter sequence (5'- TAATACGACTCACTATAGGG-3'), respectively (Table 1). Thus, from a reaction mixture composed of 0.4µL of KOD high-fidelity DNA polymerase (1U / µL, Novagen), 2µL of KOD buffer (10X), 2µL of dNTP (2mM), 1.2µL of MgSO4 (10mM), 1.2µL of sense and antisense primers (10µM), 2µL of cDNA diluted 1 / 20th and 1.2µL of H2O, the amplicons of interest are obtained after an initial denaturation at 95°C for 2 minutes followed by 30 cycles composed of 3 steps (denaturation for 20 seconds at 95°C, hybridization for 20 seconds at 60°C and elongation for 10 seconds at 70°C) then a final elongation of 5 minutes at 72°C.In parallel, the amplification of a part of the bacterial nucleotide sequence encoding β-galactosidase (140bp), present in the plasmid pCR-Blunt, is carried out using the specific primers LacZ-dsRNA (Table 1) associated with the T7 promoter sequence. This amplicon will be used for the production of control dsRNA. [Table 1]. Table 1: Primer sequences used for β2 subunit cloning, dsRNA synthesis, and qPCR. The T7 promoter sequence is boxed. PCR product purification After electrophoretic migration on a 2% agarose gel, the PCR products are purified using the NucleoSpin® Gel and PCR clean-up kit (Macherey-Nagel). Briefly, the piece of agarose gel containing the amplicons of interest is dissolved in a water bath at 50°C in NT1 buffer (200µL per 100mg of gel) containing chaotropic salts allowing the fixation of DNA on a silica membrane. After complete dissolution of the gel, the amplicons are retained by a silica membrane and two washes with 700µL of NT3 buffer (30-second centrifugations at 11000g) are performed. PCR products are eluted in 30µL of H2O by centrifugation for 1 minute at 11000g. The quality and quantity of DNA are finally evaluated by spectrophotometry (SimpliNano).Molecular cloning of the nicotinic β2 subunit Cloning of the β2 subunit is performed using the Zero Blunt© PCR Cloning kit (Invitrogen). To do this, the purified amplicons corresponding to the coding sequence of the β2 subunit are inserted into the PCR-Blunt cloning vector at an insert:vector ratio of 10:1. Thus, 1µL of pCR-Blunt plasmid (25ng / µL), 6µL of purified insert, 2µL of ExpressLink T4 DNA ligase reaction buffer (5X) and 1µL of ExpressLink T4 DNA ligase enzyme (5U / µL) are incubated for 30 minutes at room temperature. Then, 4µL of the ligation product is introduced into chemo-competent E. Coli One Shot© Top 10 bacteria following bacterial transformation by heat shock (30 minutes in ice then 45 seconds at 42°C and finally 2 minutes in ice).The transformed bacteria are incubated for 1 hour at 37°C in 250µL of SOC medium and then spread on Petri dishes containing a selective LB-agar medium supplemented with kanamycin (50µg / mL). After an overnight incubation at 37°C, the recombinant clones are selected using a PCR using M13 primers specific for the plasmid sequences flanking the insert and then cultured overnight in 5mL of LB-kanamycin medium at 37°C with shaking (225 rpm). The recombinant plasmids are finally purified using the NucleoSpin Plasmid® kit (Macherey-Nagel) and sequenced (Eurofins). In vitro transcription and dsRNA synthesis Purified PCR products (140bp) specific for a portion of the coding sequence of the β2 subunit or β-galactosidase containing the T7 promoter sequence upstream and downstream are transcribed in vitro using the MEGAscript® T7 High Yield Transcription kit (Ambion).The transcription reaction is carried out at 37°C overnight using a 20µL reaction mixture composed of 100ng of PCR products, 2µL of each nucleotide (ATP, GTP, CTP, UTP; 75mM), 2µL of reaction buffer (10X), 2µL of T7 RNA polymerase enzyme. A TURBO DNase treatment (2U) is then carried out for 15 minutes at 37°C to remove the template DNA and then the transcription products are purified using the NucleoSpin® miRNA kit (Macherey-Nagel). First, 150 µL of ML buffer and 200 µL of absolute ethanol are added to the transcription products (qsp 150 µL H2O) then the mixture is deposited on a silica membrane to fix the DNA and large RNA fragments (>200 bp). After centrifugation at 11000g for 30 seconds, 100µL of MP buffer and 800µL of MX buffer are added to the eluate containing RNA fragments smaller than 200 bp such as dsRNA to allow their precipitation and fixation on the silica membrane.In parallel, a 15-minute DNAse treatment at room temperature is carried out on the silica membrane previously desalted using 350 µL of MDB buffer (one-minute centrifugation at 11000g). After the fixation of the small RNA fragments on the silica membrane (30 sec centrifugation at 11000g), the membrane is washed twice with MW2 buffer, the dsRNAs are eluted in 30µL of H2O. Finally, the dsRNAs are denatured for 5 minutes at 95°C and then rehybridized for 1h30 at room temperature. The quality and quantity of the dsRNAs are evaluated using a spectrophotometer (SimpliNano). The dsRNAs obtained are stored at -20°C. Preparation of lipoplexes containing dsRNA and topical administration In order to facilitate the absorption of dsRNA in the aphid and limit the degradation of dsRNA, liposomes containing the different dsRNAs (lipoplexes) are produced.To do this, 400ng of dsRNA (β2 or LacZ) are brought into contact with 0.1µL of Escort IV® transfection agent (Sigma-Aldrich) in the presence of 1X PBS (qsp 1µL) for 30 minutes at room temperature. The dsRNAs are absorbed following topical administration in the adult aphid according to Niu et al (2019). Briefly, the aphids are immobilized using a piece of parafilm® that has been previously pierced in order to have access to the aphid's abdomen. Thus, 1µL of lipoplexes containing the dsRNAs is placed on the aphid's abdomen. A waiting time of 30 minutes is necessary for the drop to fully penetrate the aphid.Quantitative PCR analysis of the expression of the β2 subunit in aphids having absorbed dsRNAs Using cDNAs from different batches of aphids having absorbed dsRNAs (β2 or LacZ), the quantification of the transcripts of the β2 subunit is carried out by quantitative PCR (qPCR) in order to evaluate the effect of dsRNAs targeting the β2 subunit on the expression of this subunit at different times post-administration (2h, 24h and 72h), as well as on the expression of the different nicotinic subunits and thus highlight potential compensation phenomena. Each qPCR reaction requires 5µL of Takyon No Rox SYBR® Master Mix Blue dTTP reaction buffer (Eurogentec), 1µL of forward and reverse primers (10µM) (Table 1), 0.5µL of H2O and 2.5µL of cDNA diluted 1 / 10.The quantification program consists of a first step of 3 minutes at 95°C followed by 40 cycles of denaturation of 10 seconds at 95°C and annealing and elongation of 1 minute at the primer annealing temperature (60°C). Finally, an additional dissociation curve step ("melting curve") which allows the progressive passage of the temperature from 50°C to 95°C is carried out in order to verify the specificity of the primers. The efficiency of the different qPCR amplifications is between 97% and 102%. All reactions are carried out in duplicate and the threshold cycle (Ct) values ​​are normalized with the reference gene coding for the RPL7 protein. The fluorescence intensity emitted by the SYBR® Green I probe is detected by the CFX Connect™ Real-Time PCR Detection System (Biorad) and the data are then analyzed using CFX Maestro™ Software. The relative expression of nicotinic subunits is assessed using the 2- method.∆∆Ct . Mortality tests Mortality tests are carried out using an artificial nutrition system comprising a PVC tube closed by a parafilm® at each end in which 5 adult aphids or 20 larvae are placed. At one end of the artificial nutrition "cell", 200µL of nutrient solution comprising the solution to be tested (insecticide, dsRNA) are placed on the parafilm and then covered with a second parafilm allowing the aphids to suck up the solution to feed by piercing the parafilm with their rostrum. The cells are placed at 20°C in an enclosure with a 16-hour photoperiod. In order to determine the concentration of imidacloprid leading to 50% mortality (CL 50 ) in aphid larvae, an effect-concentration curve is established at 48h and 72h from a concentration range going from 10 -6at 10µg / mL of imidacloprid. In order to evaluate the effectiveness of the strategy using interfering RNA as a bioinsecticide, the mortality of adult aphids is observed at 24h, 48h and 72h after absorption of dsRNA. The modulatory effect of dsRNA on the sensitivity of aphids to imidacloprid will be studied by combining topical administration of dsRNA and toxicological tests with imidacloprid. Acute imidacloprid poisoning (5.10 -3 µg / mL) is carried out 2 hours after absorption of dsRNA and aphid mortality is assessed at 24, 48 and 72 hours. Insect death is validated in the absence of movement observed under a binocular microscope. The results are expressed as a percentage of mortality corrected according to the Henderson-Tilton formula to take into account aphid mortality under control conditions: [Math. 1] ^ ^^ where n VLacZ is the number of aphids alive in the control condition; n M LacZ is the number of dead aphids in the control condition; n V β2 is the number of live aphids that absorbed the dsRNAs β2 and n M β2 is the number of dead aphids that absorbed β2 dsRNA. Statistical analyses Statistical analyses of qPCR results are performed using a Mann-Withney test, using GraphPad Prism software (version 8.0.1, GraphPad Software) where p values ​​less than 0.05 are considered significant (*p<0.05, **p<0.01 and ***p<0.001). Mortality curves are obtained with GraphPad Prism software in the form of a non-linear regression and fitted according to the Hill equation, [Math. 2] where Y is the percentage mortality observed at concentration value X, m and M are respectively the minimum and maximum values ​​of the curve, nH is the Hill coefficient and CL 50is the concentration of imidacloprid resulting in 50% mortality. Results are expressed as mean ± SEM. Nature of the effect of dsRNAs In order to determine the nature of the effect of dsRNAs targeting the β2 subunit on the sensitivity of aphids to imidacloprid, the results are analyzed using the Model Deviation Ratio (MDR) formula: MDR = observed toxicity / expected toxicity where the observed toxicity corresponds to the percentage of corrected mortality of aphids having absorbed the β2 dsRNAs and exposed to imidacloprid and the expected toxicity corresponds to the sum of the percentages of corrected mortality obtained in aphids in each condition taken individually (β2 dsRNA and imidacloprid). The MDR results are interpreted as follows: if the MDR is greater than or equal to 1.3, the effect is considered synergistic; if the MDR is less than or equal to 0.7, then the effect is antagonistic; and if the MDR is between 0.7 and 1.3, the effect is additive.Results Obtaining the plasmid pCR-Blunt containing the nucleotide sequence coding for the nicotinic β2 subunit In order to confirm the nucleotide sequences (accession number XM_001945029.5, SEQ ID NO: 18) and protein sequences (accession number XP_001945064.2 SEQ ID NO: 56) coding for the β2 subunit deposited in the NCBI database in the aphids of the SiFCIR laboratory, the plasmid construction with the pCR-Blunt vector was carried out. The sequence inserted into the recombinant plasmid obtained at the end of this cloning presents 100% homology with the deposited protein sequence. Efficacy of dsRNAs on the expression of nicotinic β2 subunit transcripts In order to determine the efficacy of dsRNAs targeting the β2 subunit, the expression levels of mRNAs coding for this protein were quantified by qPCR in adult aphids that had absorbed the dsRNAs (β2 or LacZ). This quantification was carried out at different post-absorption times (2h, 24h and 72h).Thus, significant decreases in the expression of the β2 subunit of 51%, 43% and 41% were observed in aphids having absorbed the β2 dsRNAs compared to control aphids having absorbed the LacZ dsRNAs at 2h, 24h and 72h respectively (*p<0.05; Figure 1). For toxicological tests in the presence of imidacloprid associated with the absorption of dsRNAs, the incubation time of the dsRNAs of 2h will be kept. Effect of dsRNAs on aphid mortality In order to verify whether dsRNAs targeting the β2 subunit can be used as a bioinsecticide, the inventors evaluated the mortality of aphids 24h, 48h and 72h after the topical application of the dsRNAs. Preliminary results suggest an increase in mortality of aphids that absorbed dsRNA targeting the β2 subunit (β2) compared to control aphids (LacZ) by approximately 6%, 31% and 51% at 24h, 48h and 72h respectively (Figure 2; n=5 including 15 to 30 aphids per condition).Thus, the use of dsRNA as a bioinsecticide is possible under these experimental conditions, namely a single topical administration of 400ng per aphid. Evaluation of the sensitivity of aphids to imidacloprid and determination of the CL. 50 Before investigating the involvement of the β2 subunit in modulating aphid sensitivity to imidacloprid, the concentration of imidacloprid resulting in 50% insect mortality was determined. For this purpose, different concentrations of imidacloprid ranging from 10 -6 at 10µg / mL were tested. From the concentration-effect curve, the LC - 50 was estimated at 8.10 3 µg / mL and 4.10 -3 µg / mL at 48h and 72h respectively (Figure 3). The concentration of 5.10 -3µg / mL is retained for experiments combining dsRNA targeting the β2 subunit and imidacloprid. Effect of dsRNA on aphid sensitivity to imidacloprid Given that the composition of nicotinic subunits in nAChRs determines their sensitivity to insecticides, the decrease in the expression of β2 subunit mRNA by specific dsRNAs observed in aphids suggests a modification of the composition of nAChRs inducing a modulation of the efficacy of an insecticide treatment. To evaluate the effect of dsRNA as a modulator of the efficacy of an insecticide treatment, toxicological tests in the presence of imidacloprid are carried out. For this purpose, adult aphids having absorbed the dsRNA are intoxicated with imidacloprid at a concentration close to the LC 50 namely 5.10 -3µg / mL. 72 hours after acute poisoning, a slight increase in mortality (x1.4 times) is observed in aphids that have absorbed dsRNA directed against the β2 subunit compared to control aphids (LacZ) (Figure 4). Thus, the use of specific dsRNAs inducing a modification of the composition of nAChRs would make insects more sensitive to the insecticide. In order to determine the nature of the effect of the association "dsRNA β2 and imidacloprid", the results were analyzed according to the Model Deviation Ratio (MDR) and the MDR value was evaluated at 0.74. Thus, the MDR being between 0.7 and 1.3, the effect of the association dsRNA against the β2 subunit and imidacloprid is considered additive. Effect of β2 subunit reduction on the expression of other nicotinic subunits in aphid A.pisum To correlate the modification of the sensitivity of aphids having absorbed dsRNAs targeting β2 with possible changes in the composition of nAChRs, the expression levels of mRNAs corresponding to the different nicotinic subunits identified in the genome were quantified by qPCR from cDNAs from aphids having absorbed dsRNAs at different times post-administration (2h, 24h and 72h). Two hours after the administration of dsRNAs, a significant increase in the expression of mRNAs coding for subunits α1 to α8 is highlighted in aphids having absorbed the dsRNAs of interest compared to control aphids (Figure 5A) while the expression of subunits α9, α10 and β1 is not modified. At 24 h post-administration of dsRNA, only the decrease in the expression of the α9 subunit is associated with the decrease in the expression of the β2 subunit in aphids having absorbed the β2 dsRNA (Figure 5B).Finally, the decrease in the expression of the β2 subunit induced by β2 dsRNA observed at 72 hours does not appear to impact the expression of other nicotinic subunits (Figure 5C). These results allow us to consider interfering RNAs as a potentiating agent for an insecticide such as imidacloprid, with a view to reducing the amount of insecticide used in the control of harmful insects, in accordance with government guidelines. The inventors were therefore able to demonstrate an increase in the mortality of aphids having absorbed dsRNAs targeting the β2 subunit of approximately 40% from 48 hours to 72 hours post-absorption, compared to control aphids. These results suggest the opportunity to use dsRNAs directed against the β2 subunit as a bioinsecticide and suggest that this subunit is essential in aphids.Finally, aphids that absorbed dsRNA targeting the β2 subunit exhibited greater sensitivity to imidacloprid compared to control aphids that absorbed LacZ dsRNA. The results of toxicological tests suggest that the decrease in β2 subunit expression induced by the interfering RNAs of interest could lead to a modification of the composition of nicotinic receptors in aphids, making them more sensitive to the insecticide. Example 2: Use of the RNA interference technique targeting a nicotinic subunit in the cockroach as a means of restoring the sensitivity of the pest insect that has become resistant to the insecticide. In this study, the cockroach P. americana was used as a model. Indeed, this insect, whose genome has recently been sequenced but not annotated, is capable of adapting to insecticide treatment by modifying its composition in nicotinic subunits (Benzidane Y et al., 2017) and has well-identified and characterized neuronal targets of insecticides (Thany SH et al., 2007; Sinakevitch IG et al., 1996; Grolleau F et al., 2000). To date, 19 nicotinic subunits have been identified in P. americana and deposited in the NCBI database: 9 α subunits (α1 to α9) and 10 β subunits (β1 to β10) (Jones et al., 2021). The β1 subunit belonging to the majority of heteropentameric nAChRs, it represents a target of choice for dsRNAs in order to develop the RNA interference technique in the context of the invention. Materials and methods Production of dsRNA Identification of fragments of interest specific to the nicotinic β1 subunit In order to determine the nucleotide fragments (100 bp) specific to the coding sequence of the β1 subunit (NCBI accession number: MW201213.1 – SEQ ID NO: 36) necessary for the synthesis of dsRNA, the alignment of the different nicotinic subunits identified in the cockroach P.americana was performed using Clustal Omega software. PCR amplification of specific fragments The plasmid pCR-Blunt into which the nucleotide sequence of the nicotinic β1 subunit was inserted (pCR-Blunt / β1) served as a template for obtaining the fragments of interest. PCR amplification was performed using KOD Hot Start high-fidelity DNA polymerase. TM(Novagen) using the specific dsRNA-β1 primers (Table 2) supplemented with the T7 promoter sequence (5′- TAATACGACTCACTATAGGG-3') according to the following reaction mixture: 0.4 µL of KOD DNA polymerase (1 U / µL), 2 µL of KOD buffer (10X), 2 µL of dNTP (2 mM), 1.2 µL of MgSO4 (10 mM), 1.2 µL of sense and antisense primers (10 µM), 2 µL of plasmid pCR-Blunt / β1 (10 ng / µL) and H2O qs 20 µL. The amplicons were obtained after an initial denaturation at 95°C for 2 minutes followed by 30 cycles consisting of 3 steps (denaturation for 20 seconds at 95°C, hybridization for 20 seconds at 60°C and elongation for 10 seconds at 70°C) and then a final elongation of 7 minutes at 70°C. In parallel, the amplification of a part of the bacterial nucleotide sequence encoding β-galactosidase (100 bp), present in the plasmid pCR-Blunt, was carried out using the specific LacZ primers (Table 2) associated with the T7 promoter sequence.This amplicon will be used for the production of control dsRNA. [Table 2]. Table 2: Primer sequences used for dsRNA synthesis. The T7 promoter sequence is boxed. Purification of PCR products and In vitro transcription and dsRNA synthesis The protocol detailed above for the pea aphid was used. Study model: Periplaneta americana cockroaches P. americana cockroaches are raised in the SiFCIR laboratory in vivariums at a temperature of 29°C and with a cyclic photoperiod of 12 hours of light and 12 hours of darkness. They are fed and hydrated ad libitum. In order to circumvent the resistance mechanisms established by the insect, the dsRNAs will be tested on male cockroaches that have been exposed for 30 days to a sublethal dose of imidacloprid (0.025 µg / cockroach / day) according to Benzidane et al. (2017).Preparation of lipoplexes containing dsRNAs In order to orally administer dsRNAs to cockroaches and for better stability of these dsRNAs, lipoplexes, liposomes containing the different dsRNAs (β1-start, β1-end or LacZ), were formed. To do this, 0.25 µg of dsRNA (β1-start, β1-end, β1-start + β1-end, LacZ) at 0.1 µg / µL are brought into contact with 1 µL of Escort IV® transfection agent (Sigma-Aldrich) in the presence of 6.5 µL of 5% glucose solution for 30 minutes at room temperature. Ingestion of dsRNAs in cockroaches The dsRNAs are administered to cockroaches orally. Briefly, using a P10 pipette, 10 µL of lipoplex solution containing dsRNA (β1-start, β1-end, β1-start+end, LacZ) are ingested by the cockroach which is held by the wings. The effect of dsRNA as a bioinsecticide is evaluated by observing mortality at 24h, 48h, 72h and 96h post-ingestion.Dissection of the last abdominal ganglion and extraction of total RNA 96 hours after ingestion of dsRNA, cockroaches are dissected to extract the last abdominal ganglion (DGA) which contains the DUM neurons. Extraction of total RNA from the DGA is performed using the Nucleospin® RNA kit (Macherey-Nagel). The amount of extracted RNA is then assessed by a UV spectrophotometer assay (SimpliNano). Reverse transcription Reverse transcription allowing the synthesis of cDNA from mRNA is performed using the Revertaid H Minus First Strand cDNA Synthesis® kit (ThermoScientific) as described above.Quantitative PCR analysis of β1 subunit expression in cockroaches that ingested dsRNA Using cDNAs from different batches of cockroaches that ingested dsRNA (β1-start, β1-end, β1-start+end, LacZ), quantification of β1 subunit transcripts was performed by quantitative PCR (qPCR) to evaluate the effect of dsRNA on β1 subunit expression. The protocol was adapted from that used in the pea aphid, with the sense and antisense primers indicated in Table 3 (2.5 µM for the β1 subunit and 10 µM for actin used as a reference gene, and the primer annealing temperature also indicated in Table 3). [Table 3]. Table 3: Sequences of the primers used for the qPCR Results Identification of fragments of interest specific to the β1 nicotinic subunit Following the bioinformatics analysis using the alignment of the different nucleotide sequences of the nicotinic subunits of the cockroach P. americana deposited in the NCBI database, 2 fragments of 100 bp specific to the β1 nicotinic subunit were identified. The first is located at the beginning of the nucleotide sequence (nucleotides 1 to 100 – SEQ ID NO: 67) while the second is found towards the end (nucleotides 1123-1222 – SEQ ID NO: 68). Effect of dsRNA on the expression of nicotinic β1 subunit transcripts The inventors were able to demonstrate, 96 hours post-ingestion, a 20% decrease in the expression of β1 subunit transcripts in DGA from cockroaches exposed to dsRNA-β1 end and to the mixture of dsRNA-β1 start and end (*p<0.05).In contrast, the expression of β1 subunit mRNAs does not appear to be affected by β1-start dsRNAs targeting the beginning of the β1 nucleotide sequence (Figure 6). For the rest of the experiments, only β1-end dsRNAs and the mixture of β1-start and β1-end dsRNAs will be ingested by cockroaches for toxicological tests. Use of dsRNAs to circumvent resistance mechanisms in the cockroach P. americana In order to study the effectiveness of dsRNAs in restoring the loss of sensitivity observed in resistant insects, toxicological tests using cockroaches rendered less sensitive to imidacloprid following exposure to a sublethal dose of imidacloprid were undertaken. In a first step, the inventors verified that sublethal imidacloprid intoxication for 30 days induced a loss of sensitivity of cockroaches to imidacloprid (Figure 7A).Unlike cockroaches that ingested LacZ dsRNAs, 55% and 60% mortality were observed 96 hours after acute imidacloprid intoxication in cockroaches that ingested β1-end+start and β1-end dsRNAs, respectively (Figure 7B). These rates are similar to those obtained in cockroaches not exposed to the sublethal dose of imidacloprid for 30 days (Figure 7A and 7B). Thus, dsRNAs, by modifying the expression of nAChRs, would make it possible to circumvent the resistance mechanisms put in place by the insect by restoring their sensitivity to the insecticide. These results also demonstrate the interest of the technique in circumventing the resistance mechanisms put in place by the insect against the insecticide, by targeting the nicotinic subunit(s) overexpressed by resistant cockroaches, in order to restore the "sensitive" phenotype of cockroaches.Example 3: Use of the RNA interference technique targeting the nicotinic β2 subunit of Acyrthosiphon pisum by ingestion in the larva Materials and methods Obtaining one-day-old larvae and artificial nutrition system All experiments are carried out on one-day-old aphid larvae. Thus, adult aphids are recovered at the end of the transfer and are placed in an artificial nutrition system comprising a PVC tube 3cm in diameter and 6cm in height called a cell which is closed at each end by a piece of Parafilm®. In order to feed the aphids (10 adult aphids / cell), 200µL of a nutrient solution are placed on the Parafilm® at one of the two ends of the cell. The nutrient solution is then spread on the Parafilm® by placing a second Parafilm® which covers it. Aphids can thus feed by piercing the Parafilm® with their rostrum.The cells are then placed in a box containing 6-well plates filled with moistened cotton to prevent breakage of the Parafilm® and ensure optimal development of the aphids. The cells are finally placed for 24 hours in a regulated chamber at 20°C with a 16-hour photoperiod. Preparation of lipoplexes containing dsRNA and administration by ingestion Lipoplexes containing dsRNA are produced to limit their degradation in the aphid. To do this, 9µL of dsRNA (dsRNA-LacZ or dsRNA-β2; 4.44µg / µL) are incubated with 0.1µL of Escort IV® transfection agent (Sigma-Aldrich) and 0.9µL of H2O for 30 minutes at room temperature. In order for aphids to ingest dsRNAs via the artificial system, 10 µL of lipoplexes are mixed with 190 µL of nutrient solution. The preparation of dsRNAs and analysis is similar to that presented in Example 1.Results Evaluation of the effect of dsRNA-β2 ingestion on the expression of nicotinic β2 subunit transcripts: In order to evaluate the effect of dsRNAs that target the nicotinic β2 subunit (dsRNA-β2), quantification by qPCR of the mRNAs that code for this subunit is carried out from the cDNAs of aphid larvae obtained at 2h, 24h, 48h and 72h after their contact with a nutrient solution containing the dsRNAs of interest (200ng / µL). At 2 h, the expression level of β2 subunit transcripts in larvae that ingested dsRNA-β2 was reduced by 33% compared to larvae treated with control dsRNAs targeting the bacterial LacZ gene (dsRNA-LacZ; *p<0.05, FIG 8A). In contrast, from 24 h to 72 h, no significant difference in mRNA expression was observed. Thus, these results indicate that, under these conditions, ingestion of dsRNA-β2 effectively decreased the expression level of the β2 subunit after 2 h.Evaluation of the use of dsRNA-β2 as a bioinsecticide To validate the use of dsRNA-β2 as a bioinsecticide, the mortality of A. pisum larvae was evaluated at 24h, 48h and 72h after the larvae were placed in contact with a nutrient solution containing the dsRNA of interest (dsRNA-β2 or dsRNA-LacZ) at 200ng / µL. The results were expressed as a percentage of mortality corrected compared to the control condition (dsRNA-LacZ). Ingestion of dsRNA-β2 induced a significant increase in larval mortality of 19, 32 and 33% at 24h (**p<0.01), 48h (**p<0.01) and 72h (*p<0.05) respectively compared to the mortality of larvae having ingested dsRNA-LacZ (FIG 8B). Thus, dsRNA-β2 have a bioinsecticide effect and their use could be considered to control the pea aphid. This example illustrates in particular that the mode of administration by ingestion in the larva is also functional.Example 4: Molecular characterization of auxiliary proteins regulating nicotinic receptors in the pea aphid Acyrthosiphon pisum Materials and methods Identification and bioinformatics analysis of auxiliary protein sequences The protein sequences of i) Lynx, ii) UNC-50, iii) NACHO and RIC-3 of the aphid A. pisum were identified using BLASTp software (NCBI) from those of the migratory locust Locusta migratoria, the fruit fly Drosophila mojavensis and the fruit fly Drosophila melanogaster respectively. The sequence with the highest identity is considered as the reference sequence coding for the protein of interest and is therefore used to determine the corresponding nucleotide sequence in the Gene database (NCBI).Coding sequences are identified using Expasy software and sequence alignments are performed using Clustal Omega software to highlight mutations within the predicted sequences. Finally, the presence of the GPI anchor within the Lynx protein is predicted using NetGPI software. Total RNA extraction / Reverse transcription: as previously described PCR amplification of auxiliary protein coding sequences To identify the nucleotide sequences coding for the proteins of interest, namely NACHO, UNC-50, RIC-3 and Lynx, PCR amplification was performed from the cDNAs of adult A. pisum aphids, using a high-fidelity DNA polymerase, KOD Hot Start™ (Novagen).Each reaction is performed with 0.4µL of KOD Hot Start™ DNA Polymerase (1U / µL), 2µL of KOD Reaction Buffer (10X), 1.2µL of MgSO4 (10mM), 2µL of dNTPs (2mM), 2.4µL of specific sense and antisense primers (5µM), 2µL of cDNA diluted 1 / 20th and 15.6µL of H2O. The experimental conditions of the PCRs consist of an initial denaturation of 2 minutes at 95°C, followed by 35 cycles each comprising a denaturation phase of 20 seconds at 95°C, an annealing phase of 10 seconds at 45°C (NACHO, UNC-50, Lynx 1, Lynx 4 and Lynx 10C) or 60°C (RIC-3, Lynx 5 and Lynx 6) and an elongation phase at 70°C of 30 seconds (NACHO, UNC-50, Lynx 1, Lynx 4 and Lynx 10C) or 40 seconds (RIC-3, Lynx 5 and Lynx 6). This step is followed by electrophoretic migration and purification of the PCR products, then verification of the nucleotide sequences by sequencing and quantitative PCR analysis of the expression of the transcripts of the auxiliary proteins of interest.Results Identification of auxiliary proteins RIC-3, Lynx, UNC-50 and NACHO in the aphid A. pisum: The genome of the aphid A. pisum is sequenced but poorly annotated, so a search for the sequences of the proteins of interest by screening databases is therefore possible. Thus, to determine the protein and nucleotide sequences of these proteins, a bioinformatics analysis using BLASTp software (NCBI) was carried out on the database of non-redundant protein sequences of A. pisum (NCBI) using sequences known from the migratory locust Locusta migratoria for Lynx, from the fruit fly D. melanogaster for NACHO and RIC-3 and from the fruit fly D. mojavensis for UNC-50. Thus, unlike D. melanogaster which has 19 variants of RIC-3, A.pisum would only present three isoforms, named RIC-3 A (398 amino acids), RIC-3 B (496 amino acids) and RIC-3 C (502 amino acids) whose sequences have respectively 39%, 58% and 37% identity with that of the L, D and P variants of the RIC-3 protein of Drosophila. As for the Lynx protein, 5 isoforms, named Lynx 1 to Lynx 10C, have been determined while the grasshopper has 11. These isoforms, comprising 144, 162, 148, 156 and 143 amino acids, present respectively 40%, 45%, 65%, 45% and 25% identity with Lynx 1, Lynx 4, Lynx 5, Lynx 6 and Lynx 10 of L. migratoria. In order to confirm that the different Lynx isoforms identified in A. pisum possess a GPI anchor, its prediction was carried out (NetGPI software). Thus, it was demonstrated that all the Lynx sequences in A. pisum present a GPI anchor. The screening of the NACHO protein made it possible to identify 1 protein sequence in A.pisum composed of 152 amino acids with 57% identity with that of the drosophila D. melanogaster. Finally, for UNC-50, a single protein sequence of 261 amino acids, 52% of which are identical to that of the drosophila D. mojavensis, was also highlighted. Expression of NACHO, RIC-3, Lynx and UNC-50 in the aphid A. pisum qPCRs were carried out to quantify the expression levels of mRNAs coding for the auxiliary proteins NACHO and UNC-50 but also for the different isoforms of the RIC-3 and Lynx proteins in the aphid A. pisum (larvae and adults). Analysis of the expression of the different auxiliary proteins shows that the expression of Lynx 6 and NACHO is predominant in the pea aphid whatever its stage of development, unlike that of Lynx 4 and the 3 isoforms of RIC-3, which remains in the minority (FIG 9). Among the 3 RIC-3 isoforms identified in A.pisum, RIC-3 B would be the majority isoform in larvae while in adult aphids, it would be the RIC-3 A isoform (FIG 9). As for the isoforms of the Lynx protein, Lynx 6 would be more expressed than the other 4 isoforms regardless of the stage of development (FIG 9). The examples mentioned above are only preferred embodiments of the invention, and are not intended to limit the scope of the present invention. Modifications, replacements by equivalents and improvements made by the person skilled in the art without departing from the spirit of the present invention must fall within the scope of the present invention defined by the appended claims. Bibliographic references: • Gepts et al., 2005. Legumes as a Model Plant Family. Genomics for Food and Feed Report of the Cross-Legume Advances through Genomics Conference. Plant Physiol. 2005;137(4):1228-1235 • Whyard et al., 2009.Ingested double-stranded RNAs can act as species-specific insecticides. Insect Biochem Mol Biol. 2009 Nov;39(11):824-32. • Dale et al., 2010. Identification of ion channel genes in the Acyrthosiphon pisum genome. Insect Mol Biol. 2010;19(s2):141-153. • Niu et al (2019). Topical dsRNA delivery induces gene silencing and mortality in the pea aphid. Pest Manag Sci. 2019;75(11):2873-2881. • Benzidane Y et al., 2017. Subchronic exposure to sublethal dose of imidacloprid changes electrophysiological properties and expression pattern of nicotinic acetylcholine receptor subtypes in insect neurosecretory cells. Neurotoxicology. 62:239-47. • Thany SH et al., 2007. Exploring the pharmacological properties of insect nicotinic acetylcholine receptors. Trends Pharmacol Sci. 28:14-22. • Sinakevitch IG et al., 1996. Anatomy and targets of Dorsal Unpaired Median neurones in the Terminal Abdominal Ganglion of the male cockroach Periplaneta americana L. J Comp Neurol. 367:147-63. • Grolleau F et al., 2000. Dorsal unpaired median neurones in the insect central nervous system: towards a better understanding of the ionic mechanisms underlying spontaneous electrical activity. J Exp Biol. 203:1633-48. • Jones et al., 2021. The cys-loop ligand-gated ion channel gene superfamilies of the cockroaches Blattella germanica and Periplaneta americana. Pest Manag Sci. 77(8):3787-3799.

Claims

CLAIMS 1 - A method for controlling insect pests by inhibiting the translation of mRNAs of a target gene belonging to the insect's cholinergic system through RNA interference. 2 - A method according to claim 1, characterized in that it comprises the steps of: - preparing a double-stranded RNA specific to a target mRNA; - administering the double-stranded RNA to at least one insect pest in an amount effective in inducing mortality or insecticide susceptibility in the target insect. 3 - A method according to claim 1, characterized in that it comprises the steps of: - preparing a single-stranded antisense oligonucleotide specific to a target mRNA; - administering the single-stranded antisense oligonucleotide to at least one insect pest in an amount effective in inducing mortality or insecticide susceptibility in the target insect.4 - A method according to any one of claims 1 to 3, characterized in that the target mRNA is chosen from the group comprising mRNAs from the neuronal α subunit group of the nicotinic receptor, mRNAs from the neuronal β subunit group of the nicotinic receptor, mRNAs encoding auxiliary proteins and molecules, and their isoforms, and a protein from the nicotinic receptor interactome. 5 - A method according to claim 4, characterized in that the target mRNA is selected from the group consisting of mRNAs of the α neuronal subunit group of the nicotinic receptor of Acyrthosiphon pisum, namely mRNAs encoding the α1 neuronal subunit of the nicotinic receptor, mRNAs encoding the α2 neuronal subunit of the nicotinic receptor, mRNAs encoding the α3 neuronal subunit of the nicotinic receptor, mRNAs encoding the isoforms of the α4 neuronal subunit of the nicotinic receptor, mRNAs encoding the isoforms of the α6 neuronal subunit of the nicotinic receptor, mRNAs encoding the isoforms of the α7 neuronal subunit of the nicotinic receptor, mRNAs encoding the α8 neuronal subunit of the nicotinic receptor, mRNAs encoding the neuronal α9 subunit of the nicotinic receptor, mRNAs encoding the neuronal α10 subunit of the nicotinic receptor, and their isoforms;or the target mRNA is chosen from the group consisting of mRNAs from the neuronal β subunit group of the nicotinic receptor of Acyrthosiphon pisum, namely the mRNAs encoding the neuronal β1 subunit of the nicotinic receptor and the mRNAs encoding the neuronal β2 subunit of the nicotinic receptor, and their isoforms. 6 - Method according to claim 4, characterized in that the target mRNA is chosen from the group consisting of mRNAs from the group of helper proteins of the nicotinic receptor of Acyrthosiphon pisum, in particular the mRNAs encoding the isoforms of the helper proteins RIC-3 (RIC-3 A, RIC-3 B and RIC-3 C), Lynx (Lynx 1, Lynx 4, Lynx 5, Lynx 6 and Lynx 10C), NACHO, UNC-50 and TMX-3 of Acyrthosiphon pisum.; 7 - A method according to claim 4, characterized in that the target mRNA is selected from the group consisting of mRNAs of the α neuronal subunit group of the nicotinic receptor of Periplaneta americana, namely mRNAs encoding the α1 neuronal subunit of the nicotinic receptor, mRNAs encoding the α2 neuronal subunit of the nicotinic receptor, mRNAs encoding the α3 neuronal subunit of the nicotinic receptor, mRNAs encoding the isoforms of the α4 neuronal subunit of the nicotinic receptor, mRNAs encoding the α5 neuronal subunit of the nicotinic receptor, mRNAs encoding the isoforms of the α6 neuronal subunit of the nicotinic receptor, mRNAs encoding the isoforms of the α7 neuronal subunit of the nicotinic receptor, mRNAs encoding the neuronal α8 subunit of the nicotinic receptor, the mRNAs encoding the neuronal α9 subunit of the nicotinic receptor, and their isoforms;or the target mRNA is chosen from the group consisting of mRNAs from the β neuronal subunit group of the nicotinic receptor of Periplaneta americana, namely the mRNAs encoding the β1 neuronal subunit of the nicotinic receptor, the mRNAs encoding the β2 neuronal subunit of the nicotinic receptor, the mRNAs encoding the β3 neuronal subunit of the nicotinic receptor, the mRNAs encoding the β4 neuronal subunit of the nicotinic receptor, the mRNAs encoding the β5 neuronal subunit of the nicotinic receptor, the mRNAs encoding the β6 neuronal subunit of the nicotinic receptor, the mRNAs encoding the β7 neuronal subunit of the nicotinic receptor, the mRNAs encoding the β8 neuronal subunit of the nicotinic receptor, the mRNAs encoding the neuronal subunit β9 of the nicotinic receptor, the mRNAs encoding the sub-; neuronal β10 unit of the nicotinic receptor, and their isoforms. 8 - Method according to any one of claims 1 to 7, characterized in that the double-stranded RNA or single-stranded antisense oligonucleotide is administered by a topical method of administration, by spraying, by vaporization, via nanoparticles such as lipid nanoparticles, chitosan, liposomes, niosomes, cationic dendrimers, lipoplexes, by food, by trapping in a bait box, by irrigation of crops.9 - A method according to any one of claims 1-4 and 8, characterized in that the harmful insect is at least one selected from phytophagous insects, saprophagous and detritivorous insects, predatory insects, parasitic insects and commensal insects, hematophagous insects, in particular from phytophagous insects, more particularly Helicoverpa armigera, Bemisia tabaci, Plutella xylostella, Tribolium castaneum, Myzus persicae, Spodoptera frugiperda, Aphis gossypii, Nilaparvata lugens, Spodoptera exigua, Ceratitis capitata, Cydia pomonella, Acyrthosiphon pisum, Diaphorina citri or Thrips tabaci, in particular Acyrthosiphon pisum. 10 - Method according to claim 8, characterized in that the double-stranded RNA or antisense oligonucleotide is administered by feeding at least one insect with a transgenic organism expressing the double-stranded RNA or the antisense oligonucleotide. 11 - A method according to claim 10, characterized in that the transgenic organism is a transgenic plant. 12 - An insecticidal composition for harmful insects, the composition comprising a double-stranded RNA or an antisense oligonucleotide and at least one of a transfection agent and a solvent, wherein said double-stranded RNA or antisense oligonucleotide comprises a nucleotide sequence that is at least 90% identical with at least a portion of the sequence of a target mRNA, the target mRNA being selected from the group comprising the coding sequences of genes from the neuronal α subunit group of the nicotinic receptor, genes from the neuronal β subunit group of the nicotinic receptor, and their isoforms, the nucleotide sequences of genes encoding proteins and auxiliary molecules of the nicotinic receptor, and their isoforms, or for a protein of the nicotinic receptor interactome.13 - Insecticidal composition according to claim 12, wherein the transfection-promoting agent comprises a lipid compound, a liposome, a niosome, a lipid nanoparticle, a dendrimer, and an insect virus. 14 - Insecticidal composition according to any one of claims 12 or 13, further comprising one or more agents selected from a synergistic agent, a repellent agent, and an attractant agent. 15 - Insecticidal composition according to any one of claims 12 to 14, further comprising a carrier. acceptable from an agricultural, agri-food, health and / or environmental point of view. 16 - Insecticidal composition according to any one of claims 12 to 15, characterized in that the composition is formulated in the form of a bait for the harmful insect(s).17 - Plant cell, plant tissue or transgenic plant comprising at least one nucleic acid which is or is transcribed to produce a double-stranded RNA, wherein the double-stranded RNA comprises a nucleotide sequence having at least 90% identity with at least a portion of the sequence of a target mRNA, the target mRNA being selected from the group consisting of the coding sequences of genes in the neuronal subunit group α of the nicotinic receptor, the coding sequences of genes in the neuronal subunit group β of the nicotinic receptor, and their isoforms, the nucleotide sequences of genes coding for proteins and auxiliary molecules of the nicotinic receptor, and their isoforms, or for a protein of the nicotinic receptor interactome.18 - Plant cell, plant tissue, or transgenic plant according to claim 17, wherein or having the double-stranded RNA at least 20 base pairs in length, in particular 20-2000 base pairs in length, preferably 20-900 base pairs in length. 19 - Interfering RNA wherein the double-stranded RNA inhibits the translation of mRNAs corresponding to the coding sequence. from any of the genes of the neuronal α subunit group of the nicotinic receptor, of the genes of the neuronal β subunit group of the nicotinic receptor, and their isoforms, to any of the nucleotide sequences of the genes encoding the proteins and auxiliary molecules of the nicotinic receptor, and their isoforms, or to the DNA sequence encoding a protein of the nicotinic receptor interactome.20 – Antisense oligonucleotide wherein the antisense oligonucleotide inhibits the translation of mRNAs corresponding to the coding sequence of any of the genes of the neuronal α subunit group of the nicotinic receptor, of the genes of the neuronal β subunit group of the nicotinic receptor, and their isoforms, to any of the nucleotide sequences of the genes encoding the proteins and auxiliary molecules of the nicotinic receptor, and their isoforms, or to the DNA sequence encoding a protein of the nicotinic receptor interactome. 21 – Use of interfering RNA according to claim 19 or of antisense oligonucleotide according to claim 18 as a bioinsecticide. 22 - Use of interfering RNA according to claim 19 or of antisense oligonucleotide according to claim 20 as a synergizing agent of the insecticidal effect of an insecticide or of a molecule with insecticidal effect against a harmful insect.23 - Use of interfering RNA or antisense oligonucleotide according to claim 22, wherein. The insecticide comprises neonicotinoids, in particular imidacloprid, clothianidin, acetamiprid, dinotefuran, nitenpyram, thiacloprid and thiamethoxam, spinosyns, butenolides, mesoionics, sulfoximines, carbamates, pyrethroids, oxadiazines and organophosphates, or the molecule with insecticidal effect comprises a natural substance, an essential oil, or a pheromone. 24 - Use of interfering RNA according to claim 19 or of an antisense oligonucleotide according to claim 20 as an agent for restoring the sensitivity of a pest insect to an insecticide.

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