CN113785835A

CN113785835A - Compound herbicide based on benzobicyclon

Info

Publication number: CN113785835A
Application number: CN202111013060.3A
Authority: CN
Inventors: 李冬兵; 郑秀
Original assignee: Hefei Shangbang Plant Protection Technology Co ltd
Current assignee: Hefei Shangbang Plant Protection Technology Co ltd
Priority date: 2021-08-31
Filing date: 2021-08-31
Publication date: 2021-12-14

Abstract

The invention discloses a compound herbicide based on benzobicyclon, belongs to the technical field of herbicides, and particularly solves the problem that the herbicide cannot play a good role in preventing, treating and inhibiting pathogenic bacteria to cause rice blast. The herbicide comprises the following components in percentage by weight: 1-30% of benzobicyclon, 1-20% of metamifop, 1-25% of cyhalofop-butyl, 1-3% of surfactant, 2-8% of bactericide, 1-3% of dispersant, 1-3% of defoamer, 10-20% of vegetable oil and the balance of carrier. The active ingredients of the herbicide comprise the benzobicyclon, the metamifop and the cyhalofop-butyl, the three are compounded, the effects are complementary, the weeding spectrum is wider, the weeding activity is high, the weeding effect is more excellent, the bactericide is added into the herbicide, the infection of fungi and bacteria to crops is inhibited, and the weeding and bacteriostasis effects of the herbicide are enhanced.

Description

Compound herbicide based on benzobicyclon

Technical Field

The invention belongs to the technical field of herbicides, and relates to a compound herbicide based on benzobicyclon.

Background

Herbicides are agents which cause complete or selective death of weeds, also known as herbicides, and are used to kill or inhibit the growth of plants. The herbicide has the characteristics of low cost, high efficiency, simple and convenient operation, labor saving, obvious weed control effect and the like, and is widely applied in agriculture.

At present, the herbicide is limited by safety, the weed control spectrum is limited, the occurrence of weeds cannot be completely and effectively controlled by singly using a single herbicide, and some herbicides are easy to cause residual toxicity due to large water solubility, too long field lasting period, excessive use amount or uneven application; moreover, the herbicide cannot well prevent, control and inhibit pathogenic bacteria such as fungi and bacteria, so that rice blast is caused occasionally, and rice harvest is seriously threatened.

Disclosure of Invention

The invention aims to provide a compound herbicide based on benzobicyclon, which solves the technical problems mentioned in the background technology.

The purpose of the invention can be realized by the following technical scheme:

a compound herbicide based on benzobicyclon comprises the following components in percentage by weight: 1-30% of benzobicyclon, 1-20% of metamifop, 1-25% of cyhalofop-butyl, 1-3% of surfactant, 2-8% of bactericide, 1-3% of dispersant, 1-3% of defoamer, 10-20% of vegetable oil and the balance of carrier;

the compound herbicide based on the benzobicyclon is prepared by the following steps:

step A1, mixing the benzobicyclon, the metamifop, the cyhalofop-butyl and the carrier, and performing ultrasonic dispersion uniformly to obtain a mixture a;

step A2, adding a dispersing agent and a defoaming agent into the mixture a, heating to 65-75 ℃, and stirring for reaction for 3-4 hours to obtain a mixture b;

and step A3, uniformly mixing the bactericide, the vegetable oil, the surfactant and the mixture b, heating to 65-75 ℃, and carrying out heat preservation reaction for 5-7h to obtain the composite herbicide.

Further, in the step a1, the carrier is any one of deionized water, a solvent or a filler, the solvent is one or more of N, N-dimethylformamide, cyclohexanone, toluene, ethanol, ethanolamine, butyl ether, ethyl acetate and acetonitrile, and the filler is one or more of diatomaceous earth, bentonite and light calcium carbonate.

Further, in the step A2, the dispersing agent is one or more of sodium dodecyl benzene sulfonate, polyoxyethylene triphenylethylene phenyl phosphate, alkyl naphthalene sulfonate and alkylphenol polyoxyethylene ether which are mixed according to any proportion, and the defoaming agent is an organic silicon defoaming agent.

Further, in the step A3, the vegetable oil is one or more of rapeseed oil, soybean oil, peanut oil and olive oil which are mixed according to any proportion, and the surfactant is one or two of ethyl silicone oil and methyl hydrogen-containing silicone oil which are mixed according to any proportion.

Furthermore, the compound herbicide is in the form of one of soluble powder, soluble liquid, wettable powder, suspending agent, suspoemulsion and water dispersible granules.

The bactericide is prepared by the following steps:

step S1, adding 1, 2, 4-triazole-3-carboxylic acid methyl ester, methanol and hydrazine hydrate with the mass fraction of 80% into a high-pressure reaction kettle, heating to 98-102 ℃, reacting for 5-6h, cooling to room temperature, performing suction filtration, washing a filter cake for 2-3 times by using absolute ethyl alcohol, and then placing in an oven with the temperature of 60-70 ℃ for drying for 4-5h to obtain an intermediate 1;

the reaction process is as follows:

step S2, adding ethyl 4, 4-difluoroacetoacetate, trimethyl orthoformate and acetic anhydride into a three-neck flask, heating to 80-90 ℃ for reacting for 18-22h, and evaporating redundant acetic anhydride after the point plate tracking reaction is finished to obtain an intermediate 2;

the reaction process is as follows:

step S3, adding 40% by mass of methylhydrazine and toluene into a three-neck flask, cooling to 11-13 ℃, dropwise adding an intermediate 2, heating to 90 ℃, keeping the temperature, reacting for 18-21h, cooling to room temperature, dropwise adding 50% by mass of sodium hydroxide solution, stirring, reacting for 6h, extracting an organic phase for 2-3 times by using 10% by mass of sodium hydroxide solution, combining water phases, adding 37% by mass of concentrated hydrochloric acid, adjusting the pH value to 4-5, cooling, and performing suction filtration to obtain an intermediate 3;

the reaction process is as follows:

step S4, taking the intermediate 3, triethylamine and tetrahydrofuran, magnetically stirring in a three-neck flask, adding the intermediate 1 at 0 ℃, then adding 4-dimethylaminopyridine, adding N, N' -dicyclohexylcarbodiimide after the reaction liquid is clarified, heating to 25 ℃, reacting for 3 hours, concentrating the reaction liquid under reduced pressure, adding ethyl acetate into the reaction liquid, placing the reaction liquid into a refrigerator at the temperature of-1 ℃ for 12 hours, taking the organic phase, washing the organic phase for 2-3 times by respectively using a sodium bicarbonate solution with the mass fraction of 5% and a hydrochloric acid solution with the mass fraction of 2mmol/L, drying by using anhydrous sodium sulfate, and concentrating under reduced pressure to obtain the bactericide.

The reaction process is as follows:

further, in the step S1, the dosage ratio of methyl 1, 2, 4-triazole-3-carboxylate, methanol and hydrazine hydrate is 2.14-2.2 mmol: 25.3-25.5 mL: 0.11-0.14 mL.

Further, in step S2, the molar ratio of ethyl 4, 4-difluoroacetoacetate, trimethyl orthoformate and acetic anhydride is 1: 2-2.3: 6.

further, the using ratio of the methylhydrazine, the toluene, the intermediate 2 and the 50% sodium hydroxide solution in the step S3 is 34.2-35.3 g: 100-110 mL: 47.1-47.3 g: 60-65 mL.

Further, in step S4, the amount ratio of the intermediate 3, triethylamine, tetrahydrofuran, the intermediate 1, 4-dimethylaminopyridine, and N, N' -dicyclohexylcarbodiimide is 0.42 to 0.45 mol: 5.1-5.4 g: 31.7-32.5 mL: 0.41-0.45 mol: 0.5-0.6 g: 0.4-0.6 g.

The invention has the beneficial effects that: the invention aims to provide a compound herbicide based on benzobicyclon, the active ingredients of the herbicide comprise benzobicyclon, metamifop and cyhalofop-butyl, the three are compounded, the effects are complementary, the weeding spectrum is wider, the weeding activity is high, the weeding effect is more excellent, and a bactericide is added into the herbicide to inhibit the infection of fungi and bacteria to crops. The bactericide is prepared by the following steps of reacting 1, 2, 4-triazole-3-methyl carboxylate with hydrazine hydrate to generate an intermediate 1, 4, 4-difluoro ethyl acetoacetate and acetic anhydride to generate an intermediate 2, performing addition-elimination reaction on the intermediate 2 and methyl hydrazine, hydrolyzing to obtain an intermediate 3, and reacting the intermediate 3 with the intermediate 1 to generate the bactericide. The bactericide contains triazole structure, pyrazole amide structure and fluorine-containing group, wherein sp is on triazole ring²The hybridized N atom has lone pair electrons and can perform atom coordination with the central iron atom of the ferriporphyrin to hinder the formation of a ferriporphyrin ferrite complex, so that the demethylation reaction of lanosterol C-14 is inhibited, ergosterol can not be synthesized finally, and further fungal cells die, the pyrazole amide structure achieves the purpose of inhibiting the respiration of mitochondria by hindering the transfer of electrons existing on a respiratory chain so as to limit the growth of pathogenic bacteria and achieve the final sterilization purpose, the fluorine-containing group causes low surface energy of a base material, can effectively prevent the adhesion of microorganisms such as bacteria and the like on the surface, endows the base material with self-decontamination property and passive antibacterial property, effectively avoids the breeding of the bacteria, and the three cooperate with each other, so that the sterilization effect is more excellent, and the weeding and bacteriostasis effects of the herbicide are enhanced.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Preparing a bactericide:

step S1, adding 2.14mmol of 1, 2, 4-triazole-3-carboxylic acid methyl ester, 25.3mL of methanol and 0.11mL of hydrazine hydrate with the mass fraction of 80% into a high-pressure reaction kettle, heating to 98 ℃ for reaction for 5 hours, cooling to room temperature, carrying out suction filtration, washing a filter cake for 2 times by using absolute ethyl alcohol, and then placing in a 60 ℃ drying oven for drying for 4 hours to obtain an intermediate 1;

step S2, adding ethyl 4, 4-difluoroacetoacetate, trimethyl orthoformate and acetic anhydride into a three-neck flask, heating to 80 ℃ for reacting for 18 hours, and evaporating redundant acetic anhydride after point plate tracking reaction is finished to obtain an intermediate 2, wherein the molar ratio of ethyl 4, 4-difluoroacetoacetate, trimethyl orthoformate and acetic anhydride is 1: 2: 6;

step S3, adding 34.2g of 40 mass percent methylhydrazine and 100mL of toluene into a three-neck flask, cooling to 11 ℃, dropwise adding 47.1g of intermediate 2, heating to 90 ℃, carrying out heat preservation reaction for 18 hours, cooling to room temperature, dropwise adding 60mL of 50 mass percent sodium hydroxide solution, stirring and reacting for 6 hours, extracting an organic phase for 2 times by using 10 mass percent sodium hydroxide solution, combining water phases, adding 37 mass percent concentrated hydrochloric acid to adjust the pH value to 4, cooling and carrying out suction filtration to obtain an intermediate 3;

and step S4, taking 0.42mol of intermediate 3, 5.1g of triethylamine and 31.7mL of tetrahydrofuran, magnetically stirring in a three-neck flask, adding 0.41mol of intermediate 1 at 0 ℃, then adding 0.5g of 4-dimethylaminopyridine, adding 0.4g N, N' -dicyclohexylcarbodiimide after the reaction liquid is clarified, heating to 25 ℃, reacting for 3 hours, concentrating the reaction liquid under reduced pressure, adding ethyl acetate into the reaction liquid, placing the reaction liquid into a refrigerator at-1 ℃ for 12 hours, washing the organic phase for 2 times respectively by using a sodium bicarbonate solution with the mass fraction of 5% and a hydrochloric acid solution with the mass fraction of 2mmol/L, drying by using anhydrous sodium sulfate, concentrating under reduced pressure, and preparing the bactericide.

Example 2

Preparing a bactericide:

step S1, adding 2.18mmol of 1, 2, 4-triazole-3-carboxylic acid methyl ester, 25.4mL of methanol and 0.13mL of hydrazine hydrate with the mass fraction of 80% into a high-pressure reaction kettle, heating to 100 ℃, reacting for 5 hours, cooling to room temperature, carrying out suction filtration, washing a filter cake for 2 times by using absolute ethyl alcohol, and drying in a 65 ℃ oven for 4 hours to obtain an intermediate 1;

step S2, adding ethyl 4, 4-difluoroacetoacetate, trimethyl orthoformate and acetic anhydride into a three-neck flask, heating to 85 ℃ for reaction for 20 hours, performing dot-plate tracking reaction, and then evaporating redundant acetic anhydride to obtain an intermediate 2, wherein the molar ratio of ethyl 4, 4-difluoroacetoacetate, trimethyl orthoformate and acetic anhydride is 1: 2.1: 6;

step S3, adding 34.8g of methylhydrazine with the mass fraction of 40% and 105mL of toluene into a three-neck flask, cooling to 12 ℃, dropwise adding 47.2g of intermediate 2, heating to 90 ℃, carrying out heat preservation reaction for 20 hours, cooling to room temperature, dropwise adding 63mL of 50% sodium hydroxide solution with the mass fraction, stirring and reacting for 6 hours, extracting an organic phase for 2 times by using 10% sodium hydroxide solution with the mass fraction, combining water phases, adding 37% concentrated hydrochloric acid with the mass fraction to adjust the pH value to 4, cooling and carrying out suction filtration to obtain an intermediate 3;

and step S4, taking 0.44mol of intermediate 3, 5.3g of triethylamine and 32.2mL of tetrahydrofuran, magnetically stirring in a three-neck flask, adding 0.43mol of intermediate 1 at 0 ℃, then adding 0.55g of 4-dimethylaminopyridine, adding 0.5g N, N' -dicyclohexylcarbodiimide after the reaction liquid is clarified, heating to 25 ℃, reacting for 3 hours, concentrating the reaction liquid under reduced pressure, adding ethyl acetate into the reaction liquid, placing the reaction liquid into a refrigerator at-1 ℃ for 12 hours, washing the organic phase for 2 times respectively by using a sodium bicarbonate solution with the mass fraction of 5% and a hydrochloric acid solution with the mass fraction of 2mmol/L, drying by using anhydrous sodium sulfate, concentrating under reduced pressure, and preparing the bactericide.

Example 3

Preparing a bactericide:

step S1, adding 2.2mmol of 1, 2, 4-triazole-3-carboxylic acid methyl ester, 25.5mL of methanol and 0.14mL of hydrazine hydrate with the mass fraction of 80% into a high-pressure reaction kettle, heating to 102 ℃, reacting for 6h, cooling to room temperature, carrying out suction filtration, washing a filter cake for 3 times by using absolute ethyl alcohol, and drying in an oven at 70 ℃ for 5h to obtain an intermediate 1;

step S2, adding ethyl 4, 4-difluoroacetoacetate, trimethyl orthoformate and acetic anhydride into a three-neck flask, heating to 90 ℃ for reaction for 22 hours, performing dot-plate tracking reaction, and then evaporating redundant acetic anhydride to obtain an intermediate 2, wherein the molar ratio of ethyl 4, 4-difluoroacetoacetate, trimethyl orthoformate and acetic anhydride is 1: 2.3: 6;

step S3, adding 35.3g of methylhydrazine with the mass fraction of 40% and 110mL of toluene into a three-neck flask, cooling to 13 ℃, dropwise adding 47.3g of intermediate 2, heating to 90 ℃, carrying out heat preservation reaction for 21 hours, cooling to room temperature, dropwise adding 65mL of 50% sodium hydroxide solution, stirring and reacting for 6 hours, extracting an organic phase for 3 times by using 10% sodium hydroxide solution, combining water phases, adding 37% concentrated hydrochloric acid with the mass fraction to adjust the pH value to 5, cooling and carrying out suction filtration to obtain an intermediate 3;

and step S4, taking 0.45mol of intermediate 3, 5.4g of triethylamine and 32.5mL of tetrahydrofuran, magnetically stirring in a three-neck flask, adding 0.45mol of intermediate 1 at 0 ℃, then adding 0.6g of 4-dimethylaminopyridine, adding 0.6g N, N' -dicyclohexylcarbodiimide after the reaction liquid is clarified, heating to 25 ℃, reacting for 3 hours, concentrating the reaction liquid under reduced pressure, adding ethyl acetate into the reaction liquid, placing the reaction liquid into a refrigerator at the temperature of-1 ℃ for 12 hours, washing an organic phase with a sodium bicarbonate solution with the mass fraction of 5% and a hydrochloric acid solution with the mass fraction of 2mmol/L for 2-3 times, drying with anhydrous sodium sulfate, and concentrating under reduced pressure to obtain the bactericide.

Example 4

A compound herbicide based on benzobicyclon comprises the following components in percentage by weight: 1% of benzobicyclon, 5% of metamifop, 10% of cyhalofop-butyl, 1% of ethyl silicone oil, 2% of bactericide, 1% of sodium dodecyl benzene sulfonate, 1% of organic silicon defoamer, 10% of rapeseed oil and the balance of deionized water;

step A1, mixing the benzobicyclon, the metamifop, the cyhalofop-butyl and the deionized water, and performing ultrasonic dispersion uniformly to obtain a mixture a;

step A2, adding sodium dodecyl benzene sulfonate and an organic silicon defoaming agent into the mixture a, heating to 65 ℃, and stirring for reacting for 3 hours to obtain a mixture b;

and step A3, uniformly mixing the bactericide, the rapeseed oil, the ethyl silicone oil and the mixture b, heating to 65 ℃, and carrying out heat preservation reaction for 5 hours to obtain the composite herbicide.

Example 5

A compound herbicide based on benzobicyclon comprises the following components in percentage by weight: 20% of benzobicyclon, 10% of metamifop, 5% of cyhalofop-butyl, 2% of methyl hydrogen-containing silicone oil, 6% of bactericide, 2% of polyoxyethylene triphenylethylene phenyl phosphate, 2% of organic silicon defoamer, 15% of soybean oil and the balance of cyclohexanone;

step A1, mixing the benzobicyclon, the metamifop, the cyhalofop-butyl and the cyclohexanone, and performing ultrasonic dispersion uniformly to obtain a mixture a;

step A2, adding polyoxyethylene triphenylethylene phenyl phosphate and an organic silicon defoaming agent into the mixture a, heating to 70 ℃, and stirring for reacting for 3 hours to obtain a mixture b;

and step A3, uniformly mixing the bactericide, the soybean oil, the methyl hydrogen-containing silicone oil and the mixture b, heating to 70 ℃, and carrying out heat preservation reaction for 6 hours to obtain the composite herbicide.

Example 6

A compound herbicide based on benzobicyclon comprises the following components in percentage by weight: 20% of benzobicyclon, 10% of metamifop, 20% of cyhalofop-butyl, 3% of methyl hydrogen-containing silicone oil, 8% of bactericide, 3% of alkylphenol polyoxyethylene ether, 13% of organic silicon defoamer, 10% of olive oil and the balance of diatomite;

step A1, mixing the benzobicyclon, the metamifop, the cyhalofop-butyl and the diatomite, and performing ultrasonic dispersion uniformly to obtain a mixture a;

step A2, adding alkylphenol polyoxyethylene and an organic silicon defoaming agent into the mixture a, heating to 75 ℃, and stirring for reacting for 4 hours to obtain a mixture b;

and step A3, uniformly mixing the bactericide, the olive oil, the methyl hydrogen-containing silicone oil and the mixture b, heating to 75 ℃, and carrying out heat preservation reaction for 7 hours to obtain the composite herbicide.

Comparative example 1

Comparative example 1 a composite herbicide was prepared according to example 4, except that metamifop was not added.

Comparative example 2

Comparative example 2 a composite herbicide was prepared according to example 5, except that cyhalofop-butyl was not added.

Comparative example 3

Comparative example 3 a composite herbicide was prepared according to example 6, except that no bactericide was added.

Example 7

Selecting a test field as a multi-year rice heavy-load land, and respectively spraying the herbicides of examples 4-6 and comparative examples 1-3 with the disease occurrence condition of rice blast seriously over the years, investigating the disease occurrence condition, performing a field efficacy test, dividing the test field into 6 cells, wherein each cell is 25 square meters in area, spraying the herbicide for 3 times, spraying the herbicide for 50 kilograms per mu when the rice is in a break period of 7 days, spraying the herbicide for the second time 7 days after the first spraying, investigating the control effect 14 days after the second spraying, and investigating 10 clusters per cluster by five-point sampling in each cell and 50 clusters in total, recording the total number of clusters and the number of the diseased clusters, classifying according to classification standards, and calculating the disease index and the control effect, wherein the test result is shown in table 1:

TABLE 1

Item	Control effect after 7 days (%)	Control effect after 14 days (%)	Second agent post growth rate (%)
				Example 4	93.1	94.2	27.4
Example 5	93.3	94.1	26.3
				Example 6	92.1	93.2	25.2
Comparative example 1	82.6	84.2	18.4
				Comparative example 2	80.3	81.4	17.5
Comparative example 3	85.2	86.9	19.3

As is clear from Table 1, the control effect of the herbicides of examples 4 to 6 was superior to that of comparative examples 1 to 3, and the effect of the second spray after 7 days was slightly superior to that of the first spray, and further, the growth of rice was accelerated after the herbicides of examples 4 to 6 were sprayed.

Example 8

The following performance tests were performed for examples 4 to 6 and comparative examples 1 to 3, and the following performance tests were performed to test the control effect on rice blast, in which a herbicide was sprayed on rice plants, then pathogenic bacteria were inoculated, the plants were cultured at room temperature after 36 hours of moisturizing culture, the percentage of foliar infection of the plants was measured after 7 days, and the results were converted into control effects, the actual control effects being [ (blank control infection rate-treatment infection rate)/blank control infection rate ] × 100%, and the test data are shown in table 2:

TABLE 2

Example 4

Example 5

Example 6

Comparative example 1

Comparative example 2

Comparative example 3

Actual prevention effect

92.3％

92.6％

93.1％

87.3％

89.6％

53.2％

As is clear from Table 2, the herbicides of examples 4 to 6 had excellent control effects on rice blast as compared with comparative examples 1 to 3.

In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is illustrative and explanatory only and is not intended to be exhaustive or to limit the invention to the precise embodiments described, and various modifications, additions, and substitutions may be made by those skilled in the art without departing from the scope of the invention or exceeding the scope of the claims.

Claims

1. The compound herbicide based on the benzobicyclon is characterized by comprising the following components in percentage by weight: 1-30% of benzobicyclon, 1-20% of metamifop, 1-25% of cyhalofop-butyl, 1-3% of surfactant, 2-8% of bactericide, 1-3% of dispersant, 1-3% of defoamer, 10-20% of vegetable oil and the balance of carrier;

the bactericide is prepared by the following steps:

step S1, adding 1, 2, 4-triazole-3-carboxylic acid methyl ester, methanol and hydrazine hydrate into a high-pressure reaction kettle, heating to 98-102 ℃, and reacting for 5-6h to obtain an intermediate 1;

step S2, adding ethyl 4, 4-difluoroacetoacetate, trimethyl orthoformate and acetic anhydride into a three-neck flask, heating to 80-90 ℃, and reacting for 18-22h to obtain an intermediate 2;

step S3, adding methylhydrazine and toluene into a three-neck flask, cooling to 11-13 ℃, dropwise adding the intermediate 2, heating to 90 ℃, keeping the temperature and reacting for 18-21h, cooling to room temperature, dropwise adding a sodium hydroxide solution with the mass fraction of 50%, stirring and reacting for 6h, extracting an organic phase by using the sodium hydroxide solution with the mass fraction of 10%, combining water phases, adding concentrated hydrochloric acid to adjust the pH value to 4-5, and obtaining an intermediate 3;

and step S4, uniformly stirring the intermediate 3, triethylamine and tetrahydrofuran, adding the intermediate 1, 4-dimethylaminopyridine and N, N' -dicyclohexylcarbodiimide, heating to 25 ℃, reacting for 3 hours, concentrating the reaction liquid under reduced pressure, adding ethyl acetate, cooling and extracting, washing, drying and concentrating the organic phase under reduced pressure to obtain the bactericide.

2. The compound herbicide based on benzobicyclon as claimed in claim 1, wherein: the carrier is any one of deionized water, solvent and filler.

3. The compound herbicide based on benzobicyclon as claimed in claim 2, wherein: the solvent is one or more of N, N-dimethylformamide, cyclohexanone, toluene, ethanol, ethanolamine, butyl ether, ethyl acetate and acetonitrile, and the filler is one or more of diatomite, bentonite and light calcium carbonate.

4. The compound herbicide based on benzobicyclon as claimed in claim 1, wherein: the dispersant is one or more of sodium dodecyl benzene sulfonate, polyoxyethylene triphenyl vinyl phenyl phosphate, alkyl naphthalene sulfonate and alkylphenol polyoxyethylene mixed according to any proportion.

5. The compound herbicide based on benzobicyclon as claimed in claim 1, wherein: the defoaming agent is an organic silicon defoaming agent.

6. The compound herbicide based on benzobicyclon as claimed in claim 1, wherein: the vegetable oil is one or more of rapeseed oil, soybean oil, peanut oil and olive oil which are mixed according to any proportion.

7. The compound herbicide based on benzobicyclon as claimed in claim 1, wherein: the surfactant is one or two of ethyl silicone oil and methyl hydrogen-containing silicone oil which are mixed according to any proportion.

8. The compound herbicide based on benzobicyclon as claimed in claim 1, wherein: the herbicide is prepared by the following steps:

9. A mesotrione-based composite herbicide according to any one of claims 1 to 8, wherein: the compound herbicide is in the form of one of soluble powder, soluble liquid, wettable powder, suspending agent, suspoemulsion and water dispersible granule.