The invention belongs to the field of genetic engineering technology and application thereof, and in order to solve the problems of lack of high efficient TMV-resistant RNAi nano-preparation at present, complicated preparation process of medicament, poor stability and delivery efficiency of dsRNA, the invention provides an RNAi nano-preparation, preparation method thereof and application thereof in TMV prevention and control. The RNAi nano-preparation is prepared from dsRNA and chitosan nano materials, wherein, dsRNA is a highly TMV-resistant RdRP3 gene with a length of 313 bp obtained from screening, with nucleotide sequence shown in SEQ ID NO.1, and the volume ratio of the chitosan to 1 μg/μl dsRNA is 10:(1-6). The RNAi nano-preparation provided by the invention has the advantages of stronger stability and better durability of dsRNA, good biocompatibility, good biodegradability, no harm to crops, environmental friendliness and the like, and has a good application prospect in the field of TMV virus prevention and control.

The invention belongs to the field of genetic engineering technology and application thereof, and in order to solve the problems of lack of high efficient TMV-resistant RNAi nano-preparation at present, complicated preparation process of medicament, poor stability and delivery efficiency of dsRNA, the invention provides an RNAi nano-preparation, preparation method thereof and application thereof in TMV prevention and control. The RNAi nano-preparation is prepared from dsRNA and chitosan nano materials, wherein, dsRNA is a highly TMV-resistant RdRP3 gene with a length of 313 bp obtained from screening, with nucleotide sequence shown in SEQ ID NO.1, and the volume ratio of the chitosan to 1 μg/μl dsRNA is 10:(1-6). The RNAi nano-preparation provided by the invention has the advantages of stronger stability and better durability of dsRNA, good biocompatibility, good biodegradability, no harm to crops, environmental friendliness and the like, and has a good application prospect in the field of TMV virus prevention and control.

The invention belongs to the field of genetic engineering technology and application thereof, and in order to solve the problems of lack of high efficient TMV-resistant RNAi nano-preparation at present, complicated preparation process of medicament, poor stability and delivery efficiency of dsRNA, the invention provides an RNAi nano-preparation, preparation method thereof and application thereof in TMV prevention and control. The RNAi nano-preparation is prepared from dsRNA and chitosan nano materials, wherein, dsRNA is a highly TMV-resistant RdRP3 gene with a length of 313 bp obtained from screening, with nucleotide sequence shown in SEQ ID NO.1, and the volume ratio of the chitosan to 1 μg/μl dsRNA is 10:(1-6). The RNAi nano-preparation provided by the invention has the advantages of stronger stability and better durability of dsRNA, good biocompatibility, good biodegradability, no harm to crops, environmental friendliness and the like, and has a good application prospect in the field of TMV virus prevention and control.

Methods and compositions are provided which employ a silencing element that, when ingested by a pest, such as a Coleopteran plant pest or a Diabarotica plant pest, decrease the expression of a target sequence in the pest. In specific embodiments, the decrease in expression of the target sequence controls the pest and thereby the methods and compositions are capable of limiting damage to a plant. The present invention provides various target polynucleotides set forth in any one of SEQ ID NOS: 1-236 or active variants and fragments thereof, wherein a decrease in expression of one or more the sequences in the target pest controls the pest (i.e., has insecticidal activity). Further provided are silencing elements which when ingested by the pest decrease the level of the target polypeptide and thereby control the pest. In specific embodiment, the pest is D. virgifera virgifera, D. barberi, D. speciosa, or D. undecimpunctata howardi. Plants, plant part, bacteria and other host cells comprising the silencing elements or an active variant or fragment thereof of the invention are also provided.

Methods and compositions are provided which employ a silencing element that, when ingested by a pest, such as a Coleopteran plant pest or a Diabarotica plant pest, decrease the expression of a target sequence in the pest. In specific embodiments, the decrease in expression of the target sequence controls the pest and thereby the methods and compositions are capable of limiting damage to a plant. The present invention provides various target polynucleotides set forth in any one of SEQ ID NOS: 1-236 or active variants and fragments thereof, wherein a decrease in expression of one or more the sequences in the target pest controls the pest (i.e., has insecticidal activity). Further provided are silencing elements which when ingested by the pest decrease the level of the target polypeptide and thereby control the pest. In specific embodiment, the pest is D. virgifera virgifera, D. barberi, D. speciosa, or D. undecimpunctata howardi. Plants, plant part, bacteria and other host cells comprising the silencing elements or an active variant or fragment thereof of the invention are also provided.

Compositions and methods for controlling plant pests are disclosed. In particular, novel insecticidal proteins having toxicity Coleopteran and/or Lepidopteran insect pests are provided. Nucleic acid molecules encoding the novel insecticidal proteins are also provided. Methods of making the insecticidal proteins and methods of using the insecticidal proteins and nucleic acids encoding the insecticidal proteins of the invention, for example in transgenic plants to confer protection from insect damage, are also disclosed.

Compositions for providing stability to RNA may include a primary surfactant, and a metal-ion sequestrant. The primary surfactant may be a nonionic surfactant. The composition may be in a soluble liquid concentrate form and may be sufficient to provide shelf stability to RNA for one year at room temperature. Compositions for delivering RNA to a pest via exogenous, foliar application of the composition to a plant may comprise RNA; a primary surfactant; and a metal-ion sequestrant.

Compositions for providing stability to RNA may include a primary surfactant, and a metal-ion sequestrant. The primary surfactant may be a nonionic surfactant. The composition may be in a soluble liquid concentrate form and may be sufficient to provide shelf stability to RNA for one year at room temperature. Compositions for delivering RNA to a pest via exogenous, foliar application of the composition to a plant may comprise RNA; a primary surfactant; and a metal-ion sequestrant.

The invention relates to methods, uses, systems, arrays, engineered nucleotide sequences and vectors for inhibiting bacterial population growth or for altering the relative ratio of sub-populations of first and second bacteria in a mixed population of bacteria. The invention is particularly useful, for example, for treatment of microbes such as for environmental, medical, food and beverage use. The invention relates inter alia to methods of controlling microbiologically influenced corrosion (MIC) or biofouling of a substrate or fluid in an industrial or domestic system.

The invention relates to methods, uses, systems, arrays, engineered nucleotide sequences and vectors for inhibiting bacterial population growth or for altering the relative ratio of sub-populations of first and second bacteria in a mixed population of bacteria. The invention is particularly useful, for example, for treatment of microbes such as for environmental, medical, food and beverage use. The invention relates inter alia to methods of controlling microbiologically influenced corrosion (MIC) or biofouling of a substrate or fluid in an industrial or domestic system.