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CN-121974881-A - Flavonoid compound, composition and application thereof in controlling plant pests

CN121974881ACN 121974881 ACN121974881 ACN 121974881ACN-121974881-A

Abstract

The invention discloses a flavonoid compound, a composition and application thereof in controlling plant pests, wherein the structure of the flavonoid compound is shown in a formula I, and the flavonoid compound can be used for preventing piercing-sucking type mouthpart pests and rasping type mouthpart pests, in particular to insect pests caused by pea aphids (Acyrthosiphon pisum) and frankliniella occidentalis (Odontothrips loti) on alfalfa (Medicago sativa 'Ladak +'). The flavonoid compound is derived from plant secondary metabolic substances, has the advantages of good environmental compatibility, easiness in degradation, strong target specificity and the like, and accords with the development direction of green pesticides. Therefore, the invention not only provides important material basis and application basis for developing high-efficiency and safe botanical insecticide, but also has positive significance for promoting grass industry production and ecological sustainable development.

Inventors

  • YANG PEIZHI
  • WU JIAHUA
  • WU HUA
  • MA KE
  • CAO YUMAN
  • LI CHUN
  • SONG JIAXING
  • LI CHENJIAN

Assignees

  • 西北农林科技大学

Dates

Publication Date
20260505
Application Date
20260112

Claims (10)

  1. 1. The application of flavonoid compounds in controlling plant pests is characterized in that the flavonoid compounds are shown in a formula I: A formula I; wherein R1, R2 and R3 are independently selected from hydrogen, hydroxyl, C1-C6 alkoxy and a glycoside group, R4 is selected from hydrogen, methyl and a glycoside group, and the glycoside group is selected from glucosyl, rhamnosyl, rutinoside or neohesperidin.
  2. 2. The use according to claim 1, wherein the flavonoid is selected from one or more of the compounds of formula I-1, formula I-2 and formula I-3: Formula I-1; Formula I-2; formula I-3.
  3. 3. The method according to claim 1, wherein the pests are piercing-sucking mouthparts pests and rasping-sucking mouthparts pests, and the plant is alfalfa.
  4. 4. A preparation method of a flavonoid compound shown in a formula I-1 is characterized in that the flavonoid compound shown in the formula I-1 is extracted and obtained from alfalfa by adopting the modes of extraction, column purification, acid hydrolysis and recrystallization.
  5. 5. The method for preparing flavonoid compounds according to claim 4, which comprises the following steps: Step 1.1, taking a dry sample of the aerial parts of alfalfa, grinding, crushing, sieving, collecting undersize powder and keeping away from light for later use; Step 1.2, adding a mixed solvent of ethanol and water into alfalfa powder, carrying out reflux extraction, filtering after extraction is finished, repeating the reflux extraction operation for a plurality of times on filter residues, and combining all the extraction filtrates; Step 1.3, extracting filtrate, concentrating under reduced pressure to obtain crude concentrated solution containing flavonoid components, loading the crude concentrated solution to an adsorption column, eluting with water, eluting with a mixed solvent of ethanol and water after effluent liquid has no sugar reaction, collecting eluent, concentrating under reduced pressure again until no alcohol smell exists, and obtaining refined concentrated solution of flavonoid; step 1.4, adding a hydrochloric acid solution into the flavone refined concentrated solution for hydrolysis reaction; Step 1.5, after the hydrolysis is finished, naturally cooling the reaction liquid to room temperature, and sequentially extracting, washing and drying; step 1.6, concentrating the dried organic phase under reduced pressure to obtain a crude product; step 1.7, adding a mixed solvent of ethanol and water into the crude product, and stirring until the crude product is completely dissolved to obtain a hot solution; Step 1.8, slowly dropwise adding deionized water into the hot solution, and stirring while dropwise adding until the solution is slightly turbid; and 1.9, after crystallization is completed, suction filtering and collecting precipitated crystals, and then washing and drying sequentially to finally obtain the flavonoid compound shown in the formula I-1.
  6. 6. A composition is characterized by comprising flavonoid compounds shown in a formula I, wherein the preparation form of the composition comprises wettable powder, soluble liquid and aqueous emulsion.
  7. 7. The composition of claim 8, wherein the wettable powder comprises 10-25 wt% of flavonoid compounds, 5-8 wt% of dispersing agents, 2-4 wt% of wetting agents, 1-2 wt% of stabilizing agents and the balance of solid carriers, wherein the total mass of raw materials is 100-wt%; the flavonoid compound is selected from one or more of compounds shown in a formula I-1, a formula I-2 and a formula I-3; the dispersing agent is one or more selected from alkyl naphthalene sulfonate formaldehyde condensate and sodium lignin sulfonate; the wetting agent is selected from one or more of saponin and sodium dodecyl sulfate; The stabilizer is one or more selected from epoxidized soybean oil and 2, 6-di-tert-butyl-p-cresol; The solid carrier is one or more selected from diatomite, bentonite and kaolin.
  8. 8. The composition of claim 7, wherein the wettable powder has a particle size d90 less than or equal to 15 μm.
  9. 9. The composition of claim 8, wherein the soluble liquid comprises 10-25wt% of flavonoid compound shown in formula I, 5-10wt% of emulsifying agent, 0.3-2wt% of antioxidant and the balance of water, wherein the mass sum of the raw materials is 100 wt%, and the emulsifying agent is one or a mixture of more of alkylphenol ethoxylates, benzyl phenol ethoxylates, fatty alcohol ethoxylates and castor oil ethoxylates; the aqueous emulsion comprises 10-25 wt% of flavonoid compound shown in formula I, 5-10 wt% of emulsifying agent, 0.3-2 wt% of antioxidant, 10-25 wt% of organic solvent and the balance of water, wherein the total mass of the raw materials is 100 wt%, the emulsifying agent is one or more of alkylphenol ethoxylate, benzyl phenol ethoxylate, fatty alcohol ethoxylate and castor oil ethoxylate, and the organic solvent is one or more of ethanol, isopropanol, xylene and DMSO.
  10. 10. Use of a composition according to any one of claims 6 to 9 for controlling plant pests.

Description

Flavonoid compound, composition and application thereof in controlling plant pests Technical Field The invention belongs to the technical field of agricultural pest control, relates to application of flavonoid compounds in biological pesticides for controlling plant pests, and in particular relates to a flavonoid compound, a composition and application of the flavonoid compound in controlling plant pests. Background In agricultural production, common pests such as aphids, thrips and the like cause serious harm to the growth and development of crops, and the plants often reduce the yield and the quality. At present, chemical pesticides are still used as main pesticides for preventing and controlling the pests, but a series of outstanding problems are easily brought about by long-term massive use, including environmental pollution, development of drug resistance of the pests, exceeding of pesticide residues of agricultural products and the like. The plant source active ingredient is gradually the key point of the development of green pesticides due to the advantages of natural sources, good environmental compatibility, difficult induction of drug resistance and the like. However, the existing plant source substances still have certain limitations in the aspects of insecticidal activity, action spectrum, crop safety and the like, and a novel plant source insecticidal component with high efficiency and environmental safety needs to be discovered. In view of the variety of known plant source active ingredients, the system screens out compounds which have obvious insecticidal activity and have no adverse effect on plant growth, and has important practical significance for developing environment-friendly pesticides. The flavonoid derivative is environment-friendly and safe to human and livestock, can be used for developing natural green botanical pesticides, has the characteristics of low toxicity, low residue, high selectivity and the like, and lays a foundation for developing novel environment-compatible pesticides. However, the application of the flavonoid derivative in preventing and controlling agricultural pests such as aphids, thrips and the like has not been reported in systematic research and disclosure. Disclosure of Invention Aiming at the defects existing in the prior art, the invention aims to provide a flavonoid compound, a composition and application thereof in controlling plant pests, and solves the technical problems that the flavonoid compound is difficult to have high-efficiency insecticidal activity and crop safety in the prior art. In order to solve the technical problems, the invention adopts the following technical scheme: The flavonoid compound is used for preventing and controlling plant pests, and is shown in a formula I: Formula I. Wherein R1, R2 and R3 are independently selected from hydrogen, hydroxyl, C1-C6 alkoxy and a glycoside group, R4 is selected from hydrogen, methyl and a glycoside group, and the glycoside group is selected from glucosyl, rhamnosyl, rutinoside or neohesperidin. Preferably, the flavonoid compound is selected from one or more of the compounds shown in the formula I-1, the formula I-2 and the formula I-3: Formula I-1. Formula I-2. Formula I-3. Preferably, the pests are piercing-sucking mouthparts pests and rasping-sucking mouthparts pests, more preferably, the piercing-sucking mouthparts pests are pea aphids (Acyrthosiphon pisum), and the rasping-sucking mouthparts pests are frankliniella occidentalis (Odontothrips loti). The invention also has the following technical characteristics: The invention also provides a preparation method of the flavonoid compound shown in the formula I-1, which adopts the modes of extraction, column purification, acid hydrolysis and recrystallization to extract and obtain the flavonoid compound shown in the formula I-1 from the alfalfa. The method specifically comprises the following steps: Step 1.1, taking a dry sample of the aerial parts of alfalfa, grinding, crushing, sieving, collecting undersize powder and keeping away from light for later use. And 1.2, adding a mixed solvent of ethanol and water into alfalfa powder, carrying out reflux extraction, filtering after extraction, repeating the reflux extraction operation for a plurality of times on filter residues, and combining all the extraction filtrates. And 1.3, concentrating the extracted filtrate under reduced pressure to obtain a crude concentrated solution containing flavonoid components, loading the crude concentrated solution to an adsorption column, eluting with water, eluting with a mixed solvent of ethanol and water after the effluent is subjected to sugar-free reaction, collecting the eluent, and concentrating under reduced pressure until no alcohol smell exists, thereby obtaining the refined concentrated solution of flavonoid. And 1.4, adding a hydrochloric acid solution into the flavone refined concentrated solution to carry out hydrolysis reaction. And 1.5, naturally