CN115053905A

CN115053905A - Pesticide composition, method and application

Info

Publication number: CN115053905A
Application number: CN202210805163.1A
Authority: CN
Inventors: 张亚璨; 牛海林; 崔洁; 张莎莎; 张志强; 刘浩; 庄严
Original assignee: Hebei Shangrui Biotechnology Co ltd
Current assignee: Hebei Shangrui Biotechnology Co ltd
Priority date: 2022-07-08
Filing date: 2022-07-08
Publication date: 2022-09-16

Abstract

The invention relates to the technical field of pesticide compositions, and particularly relates to a pesticide composition, a method and application. The pesticide composition comprises osthole and chitosan; wherein the mass ratio of osthole to chitosan is 1-5: 1. The osthole and chitosan have synergistic bactericidal effect in the composition, have no antagonistic effect, have better bactericidal effect than the osthole or chitosan alone, and can show better synergistic effect when the mass ratio of the osthole to the chitosan is in the range. The composition can effectively kill powdery mildew and downy mildew of cucumber, effectively prevent and treat powdery mildew and downy mildew of cucumber, has no pollution to the environment, and is a safe and efficient botanical compound biological pesticide bactericide.

Description

Pesticide composition, method and application

Technical Field

The invention relates to the technical field of pesticide compositions, and particularly relates to a pesticide composition, a method and application.

Background

Cucumber powdery mildew, commonly known as white hair disease, is a common cucumber disease and is mainly caused by infection of cucumber powdery mildew and cucumber single-capsule shell powdery mildew. Usually, the cucumber seedling pulling seedling-.

In the prior art, the control of cucumber powdery mildew is mainly based on agricultural control and chemical control, and firstly, disease-resistant varieties are selected, cultivation management is enhanced, and then chemical agents are combined for control. The chemical pesticide for preventing and treating powdery mildew of cucumber mainly comprises triadimefon, myclobutanil, difenoconazole, hexaconazole, diethylether phenol, pyraclostrobin, tetraconazole and the like.

Cucumber downy mildew, also known as mycosis latreiliana, is caused by infection of pseudoperonospora cubensis, mainly harms leaves, stems and inflorescences, can be attacked from cucumber during the seedling stage to the adult stage, and is particularly serious in the cucumber harvesting stage. It is the most serious epidemic disease of the cucumber in the sunlight greenhouse, and most leaves of the cucumber plant die and the cucumber field is withered and yellow within one week and two weeks after the cucumber is infected with downy mildew.

The control of cucumber downy mildew is mainly based on agricultural control and chemical control. Firstly, selecting a disease-resistant variety, soaking the variety for accelerating germination, and culturing strong seedlings; healthy and healthy disease-free seedlings are selected, cultivation management is enhanced, and fertilizer is applied scientifically; and finally, the composition is combined with a chemical agent for prevention and treatment. The chemical pesticide for preventing and treating cucumber downy mildew mainly comprises dimethomorph, cymoxanil, flumorph, cyazofamid, fluopicolide, propamocarb, famoxadone and the like.

At present, agricultural control and chemical control methods adopted for treating cucumber powdery mildew and downy mildew have poor effect, the resistance of diseases is continuously increased along with frequent application of medicines, a higher control level cannot be achieved even by using a larger dose, and the environmental pollution caused by chemical agents is very large.

Disclosure of Invention

Aiming at the technical problems, the invention provides a pesticide composition which can effectively prevent and treat powdery mildew and downy mildew of cucumber in a new combination mode, solves the resistance problem of powdery mildew and downy mildew of cucumber and achieves ideal prevention and treatment effect.

In order to solve the technical problem, the embodiment of the invention adopts the following technical scheme:

in a first aspect, embodiments of the present invention provide a pesticide composition, where the pesticide composition includes osthole and chitosan; wherein the mass ratio of the osthole to the chitosan is 1-5: 1.

The pesticide composition combined in a new mode has the advantages that the osthole and the chitosan have synergistic bactericidal action in the composition, no antagonistic action exists, the bactericidal effect is superior to that of the osthole or the chitosan which is singly used, and better synergistic action can be shown when the mass ratio of the osthole to the chitosan is within the range. The composition can effectively kill powdery mildew and downy mildew of cucumber, effectively prevent and treat powdery mildew and downy mildew of cucumber, has no pollution to the environment, and is a safe and efficient botanical compound biological pesticide bactericide.

When the osthole adopted by the invention acts on fungi such as powdery mildew, downy mildew and the like, the growth of fungal cell walls can be inhibited, and a large amount of hyphae are broken to die.

The chitosan adopted by the invention is a polysaccharide biological macromolecule, can generate free phenol compounds, inhibit the growth of pathogenic bacteria, play a role in sterilizing crops, can induce plants to generate enzymes to dissolve shells of pathogenic bacteria and insects, and can play a role in killing insects while sterilizing; the chitosan can also form a protective film on the leaf surface, reduce the loss of water and nutrients of plants, and promote photosynthesis and the digestion reduction reaction of nitric acid and nitrogen, thereby promoting the absorption of nutrient substances by the plants and promoting the growth of the plants.

The pesticide composition disclosed by the invention can inhibit the growth of cell walls of powdery mildew and downy mildew of cucumber under the synergistic effect of osthole and chitosan, so that hyphae are broken and die, a good control effect is achieved, the plant growth is promoted, the pesticide composition is a safe and efficient botanical compound biopesticide bactericide, the environmental pollution is low, the economic value is high, and the pesticide composition can be widely popularized and used.

Preferably, the mass ratio of the osthole to the chitosan is 1-4:1, and in the ratio range, better synergistic effect is shown.

Preferably, the optimal mass ratio of the osthole to the chitosan is 4:1, and the synergistic effect of the osthole and the chitosan and the sterilization effect of the pesticide composition are the best under the optimal ratio, so that powdery mildew and downy mildew of cucumber can be killed more effectively, powdery mildew and downy mildew of cucumber can be effectively prevented, and a more ideal prevention and treatment effect can be achieved.

Preferably, in order to further enhance the bactericidal effect, the pesticide composition of the present invention further comprises: allyl isothiocyanate; wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate is 1-5:1: 0.5-1.

The allyl isothiocyanate is a botanical broad-spectrum efficient bactericide, has a remarkable inhibiting effect on the growth of fungal hyphae, can inhibit the growth of pathogenic bacteria for a long time, has little pesticide residue on fruits and vegetables, and has high safety on human bodies. The osthole, chitosan and allyl isothiocyanate are combined to show synergistic effect.

The pesticide composition synthesized by the osthole, the chitosan and the allyl isothiocyanate within the mass range has the advantages of more obvious synergistic effect, more excellent bactericidal performance, more lasting bactericidal effect, capability of inhibiting the growth of fungi for a long time, less pesticide residue in fruits and vegetables and high safety to human bodies.

Preferably, the mass ratio of the osthole to the chitosan to the allyl isothiocyanate is 1-4:1:0.5-1, and in this ratio range, a better synergistic effect is exhibited.

Preferably, the optimal mass ratio of the osthole to the chitosan to the allyl isothiocyanate is 4:1:1, and the osthole, the chitosan and the allyl isothiocyanate have stronger synergistic effect under the ratio, have more remarkable sterilization effect on cucumber powdery mildew and downy mildew, and can effectively prevent and treat the cucumber powdery mildew and the downy mildew.

Preferably, the pesticide composition further comprises a solubilizer, a thickener and an emulsifier.

Preferably, the solubilizer includes any one of the following: n-methyl pyrrolidone, polyethylene glycol or propylene glycol, preferably N-methyl pyrrolidone, wherein the N-methyl pyrrolidone is a polar solvent with strong selectivity and good stability, and can well dissolve osthole.

Preferably, the thickener comprises any one of: hydroxymethyl fibres, alkyl polyglycosides or polyacrylic acids, preferably alkyl polyglycosides. The alkyl polyglycoside has the advantages of excellent solubility, good thickening effect, strong antibacterial activity, easy dilution, convenient use, acid and alkali resistance, hard water and strong salt resistance, and can also reduce the surface tension of the solution, enable the liquid drops to be paved on the surface of a plant, increase the contact area of the liquid drops and the plant and enhance the sterilization effect.

Preferably, the emulsifier comprises any one of the following: c13 nonionic half-branched fatty alcohol-polyoxyethylene ether, phosphate ester or alkylphenol ethoxylate, preferably C13 nonionic half-branched fatty alcohol-polyoxyethylene ether. The C13 nonionic half-branched fatty alcohol-polyoxyethylene ether is a nonionic surfactant, can reduce the surface tension of the solution by cooperating with alkyl polyglycoside, enables liquid drops to be better paved on the surface of a plant, increases the contact area of the liquid drops and the plant, and further enhances the sterilization effect of the solution.

In a second aspect, an embodiment of the present invention further provides a pesticide composition solution, including the following components, by mass: 10-25% of osthole, 4-13% of chitosan, 8-10% of N-methyl pyrrolidone, 50-55% of water, 1-4% of alkyl polyglycoside and 3-6% of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether, for example, 20% of osthole, 5% of chitosan, 10% of N-methyl pyrrolidone, 55% of water, 4% of alkyl polyglycoside and 6% of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether.

In the embodiment of the invention, the cnidium lactone 10-25% and chitosan 4-13% have synergistic effect on cucumber powdery mildew and downy mildew; within the range of 8-10% of N-methyl pyrrolidone, 50-55% of water, 1-4% of alkyl polyglycoside and 3-6% of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether, the solute in the solution is fully dissolved, the surface tension of the solution is reduced, and the sterilization effect is good.

The pesticide composition solution can also comprise the following components in percentage by mass: 10% -25% of osthole, 4% -13% of chitosan, 4% -10% of isothiocyanato-allyl ester, 8% -10% of N-methyl pyrrolidone, 50% -55% of water, 1% -4% of alkyl polyglycoside and 3% -6% of C13 nonionic half-branched fatty alcohol polyoxyethylene ether, for example, 20% of osthole, 5% of chitosan, 5% of isothiocyanato-allyl ester, 10% of N-methyl pyrrolidone, 50% of water, 4% of alkyl polyglycoside and 6% of C13 nonionic half-branched fatty alcohol polyoxyethylene ether.

In the embodiment of the invention, the osthole has remarkable synergistic effect within the range of 10-25 percent, 5-10 percent of chitosan and 5-10 percent of allyl isothiocyanate; the solute in the prepared liquid is dissolved more uniformly in the range of 8-10% of N-methyl pyrrolidone, 50-55% of water, 1-4% of alkyl polyglycoside and 3-6% of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether.

In the pesticide composition solution, the alkyl polyglycoside and the C13 nonionic half-branched fatty alcohol-polyoxyethylene ether can synergistically reduce the surface tension of liquid drops in the pesticide composition solution, so that the liquid drops can be better paved on the surface of a plant, the contact area of the liquid drops and the plant is increased, the sterilization effect of the solution is enhanced, and the synergistic effect is remarkable due to the combined use of the osthole and the chitosan or the combined use of the osthole, the chitosan and the allyl isothiocyanate, and is safe and pollution-free to the environment.

In a third aspect, the embodiment of the present invention also provides a preparation method of the above pesticide composition, including the following steps:

when the components do not contain allyl isothiocyanate, the preparation method comprises the following steps:

adding the osthole and the N-methylpyrrolidone into water with the formula amount of 40% -60% to obtain a first mixed solution;

adding the chitosan into the residual water to obtain a second mixed solution;

uniformly mixing and stirring the first mixed solution and the second mixed solution to obtain a third mixed solution;

adding the C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and alkyl polyglycoside into the third mixed solution, and uniformly stirring until the mixture is clear;

when the components contain allyl isothiocyanate, the preparation method comprises the following steps:

adding the osthole and the N-methylpyrrolidone into water with the formula amount of 40-60% to obtain a first mixed solution;

adding the chitosan and the allyl isothiocyanate into the residual water to obtain a second mixed solution;

and adding the C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and alkyl polyglycoside into the third mixed solution, and uniformly stirring until the mixture is clear.

The preparation method of the pesticide composition can obtain a uniform target solution through the preparation process.

In a fourth aspect, the embodiment of the invention also provides an application of the pesticide composition in controlling cucumber powdery mildew and downy mildew.

The pesticide composition disclosed by the invention is used for preventing and treating powdery mildew and downy mildew of cucumber, shows a synergistic interaction effect, and can inhibit the growth of cell walls of powdery mildew and downy mildew of cucumber to cause hyphae to break and die, so that a good prevention and treatment effect is achieved, the growth of cucumber plants can be promoted, and the resistance of cucumber to powdery mildew and downy mildew of cucumber is improved.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In order to better illustrate the invention, it is further illustrated by the following specific examples.

Example 1

The embodiment provides a pesticide composition, which comprises the following components: osthole and chitosan; wherein the mass ratio of osthole to chitosan is 1: 1.

The formulation of the drug solution was as follows:

weighing 125g of osthole and 100g of N-methylpyrrolidone, adding 225g of water for dissolving, and uniformly stirring to obtain a first mixed solution; weighing 125g of chitosan, adding 225g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

mixing and stirring the first mixed solution and the second mixed solution uniformly to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the mixture is clear to obtain a target solution; in the target solution, the mass ratio of osthole to chitosan is 1: 1.

Example 2

The embodiment provides a pesticide composition, which comprises the following components: osthole and chitosan; wherein the mass ratio of the osthole to the chitosan is 2: 1.

The formulation of the drug solution was as follows:

weighing 166.7g of osthole and 100g of N-methylpyrrolidone, adding 225g of water for dissolving, and uniformly stirring to obtain a first mixed solution; weighing 83.3g of chitosan, adding 225g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

mixing and stirring the first mixed solution and the second mixed solution uniformly to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the third mixed solution is clear to obtain a target solution, wherein the mass ratio of the osthole to the chitosan in the target solution is 2: 1.

Example 3

The embodiment provides a pesticide composition, which comprises the following components: osthole and chitosan; wherein the mass ratio of the osthole to the chitosan is 3: 1.

The formulation of the drug solution was as follows:

weighing 187.5g of osthole and 100g of N-methylpyrrolidone, adding 225g of water for dissolving, and uniformly stirring to obtain a first mixed solution; weighing 62.5g of chitosan, adding 225g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

uniformly mixing and stirring the first mixed solution and the second mixed solution to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the third mixed solution is clear to obtain a target solution, wherein the mass ratio of the osthole to the chitosan in the target solution is 3: 1.

Example 4

The embodiment provides a pesticide composition, which comprises the following components: osthole and chitosan; wherein the mass ratio of the osthole to the chitosan is 4: 1.

The formulation of the drug solution was as follows:

weighing 200g of osthole and 100g of N-methylpyrrolidone, adding 225g of water for dissolving, and uniformly stirring to obtain a first mixed solution; weighing 50g of chitosan, adding 225g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

mixing and stirring the first mixed solution and the second mixed solution uniformly to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the third mixed solution is clear to obtain a target solution, wherein the mass ratio of the osthole to the chitosan in the target solution is 4: 1.

Example 5

The embodiment provides a pesticide composition, which comprises the following components: osthole and chitosan; wherein the mass ratio of the osthole to the chitosan is 5: 1.

The formulation of the drug solution was as follows:

weighing 208.4g of osthole and 100g of N-methylpyrrolidone, adding 225g of water for dissolving, and uniformly stirring to obtain a first mixed solution; weighing 41.6g of chitosan, adding 225g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

mixing and stirring the first mixed solution and the second mixed solution uniformly to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the third mixed solution is clear to obtain a target solution, wherein the mass ratio of the osthole to the chitosan in the target solution is 5: 1.

Example 6

The embodiment provides a pesticide composition, which comprises the following components: osthole, chitosan and allyl isothiocyanate; wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate is 1:1: 1.

The formulation of the drug solution was as follows:

weighing 100g of osthole and 100g of N-methylpyrrolidone, adding 250g of water for dissolving, and uniformly stirring to obtain a first mixed solution; weighing 100g of chitosan and 100g of allyl isothiocyanate, adding the chitosan and the allyl isothiocyanate into 250g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

mixing and stirring the first mixed solution and the second mixed solution uniformly to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the mixture is clear to obtain a target solution, wherein the mass ratio of the osthole, the chitosan and the allyl isothiocyanate in the target solution is 1:1: 1.

Example 7

The embodiment provides a pesticide composition, which comprises the following components: osthole, chitosan and allyl isothiocyanate; wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate is 2:1: 1.

The formulation of the drug solution was as follows:

weighing 150g of osthole and 100g of N-methylpyrrolidone, adding 250g of water for dissolving, and uniformly stirring to obtain a first mixed solution; weighing 75g of chitosan and 75g of allyl isothiocyanate, adding 250g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

mixing and stirring the first mixed solution and the second mixed solution uniformly to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the mixture is clear to obtain a target solution, wherein the mass ratio of the osthole, the chitosan and the allyl isothiocyanate in the target solution is 2:1: 1.

Example 8

The embodiment provides a pesticide composition, which comprises the following components: osthole, chitosan and allyl isothiocyanate; wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate is 3:1: 1.

The formulation of the drug solution was as follows:

weighing 180g of osthole and 100g of N-methylpyrrolidone, adding 250g of water for dissolving, and uniformly stirring to obtain a first mixed solution; weighing 60g of chitosan and 60g of allyl isothiocyanate, adding the chitosan and the allyl isothiocyanate into 250g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

mixing and stirring the first mixed solution and the second mixed solution uniformly to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the mixture is clear to obtain a target solution, wherein the mass ratio of the osthole, the chitosan and the allyl isothiocyanate in the target solution is 3:1: 1.

Example 9

The embodiment provides a pesticide composition, which comprises the following components: osthole, chitosan and allyl isothiocyanate; wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate is 4:1: 1.

The formulation of the drug solution was as follows:

weighing 200g of osthole and 100g of N-methylpyrrolidone, adding 250g of water for dissolving, and uniformly stirring to obtain a first mixed solution; weighing 50g of chitosan and 50g of allyl isothiocyanate, adding the chitosan and the allyl isothiocyanate into 250g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

uniformly mixing and stirring the first mixed solution and the second mixed solution to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the mixture is clear to obtain a target solution, wherein the mass ratio of the osthole, the chitosan and the allyl isothiocyanate in the target solution is 4:1: 1.

Example 10

The embodiment provides a pesticide composition, which comprises the following components: osthole, chitosan and allyl isothiocyanate; wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate is 5:1: 1.

The formulation of the drug solution was as follows:

weighing 214.4g of osthole and 100g of N-methylpyrrolidone, adding 250g of water for dissolving, and uniformly stirring to obtain a first mixed solution; weighing 42.8g of chitosan and 42.8g of allyl isothiocyanate, adding the chitosan and the allyl isothiocyanate into 250g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

mixing and stirring the first mixed solution and the second mixed solution uniformly to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the mixture is clear to obtain a target solution, wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate in the target solution is 5:1: 1.

Example 11

The embodiment provides a pesticide composition, which comprises the following components: osthole, chitosan and allyl isothiocyanate; wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate is 1:1: 0.5.

The formulation of the drug solution was as follows:

weighing 120g of osthole and 100g of N-methylpyrrolidone, adding 250g of water for dissolving, and uniformly stirring to obtain a first mixed solution; weighing 120g of chitosan and 60g of allyl isothiocyanate, adding 250g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

mixing and stirring the first mixed solution and the second mixed solution uniformly to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the mixture is clear to obtain a target solution, wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate in the target solution is 1:1: 0.5.

Example 12

The embodiment provides a pesticide composition, which comprises the following components: osthole, chitosan and allyl isothiocyanate; wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate is 4:1: 0.5.

The formulation of the drug solution was as follows:

weighing 218g of osthole and 100g of N-methylpyrrolidone, adding 250g of water for dissolving, and uniformly stirring to obtain a first mixed solution; weighing 54.5g of chitosan and 27.5g of allyl isothiocyanate, adding the chitosan and the allyl isothiocyanate into 250g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

mixing and stirring the first mixed solution and the second mixed solution uniformly to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the mixture is clear to obtain a target solution, wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate in the target solution is 4:1: 0.5.

Example 13

The embodiment provides a pesticide composition, which comprises the following components: osthole, chitosan and allyl isothiocyanate; wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate is 5:1: 0.5.

The formulation of the drug solution was as follows:

230.5g of osthole and 100g of N-methylpyrrolidone are weighed, added into 250g of water for dissolving, and stirred uniformly to obtain a first mixed solution; weighing 46g of chitosan and 23.5g of allyl isothiocyanate, adding 250g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

mixing and stirring the first mixed solution and the second mixed solution uniformly to obtain a third mixed solution; adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the third mixed solution, and uniformly stirring until the mixture is clear to obtain a target solution, wherein the mass ratio of the osthole to the chitosan to the allyl isothiocyanate in the target solution is 5:1: 0.5.

Comparative example 1

Control solution: a control solution was prepared by adding 100g of N-methylpyrrolidone, 60g of C13 nonionic half-branched fatty alcohol polyoxyethylene ether and 40g of alkylpolyglycoside to 800g of water.

Comparative example 2

This example provides a one-component pesticide comprising the following ingredients: osthole is prepared from cnidium lactone.

The formulation of the drug solution was as follows:

weighing 200g of osthole and 100g of N-methylpyrrolidone, adding 600g of water for dissolving, and uniformly stirring to obtain a first mixed solution;

and adding 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the first mixed solution, and uniformly stirring until the mixture is clear to obtain a target solution.

Comparative example 3

This example provides a one-component pesticide comprising the following ingredients: and (3) chitosan.

The formulation of the drug solution was as follows:

weighing 50g of chitosan, adding 750g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

and adding 100g of N-methylpyrrolidone, 60g of C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and 40g of alkyl polyglycoside into the second mixed solution, and uniformly stirring until the mixture is clarified to obtain a target solution.

Comparative example 4

This example provides a one-component pesticide comprising the following ingredients: allyl isothiocyanate.

The formulation of the drug solution was as follows:

weighing 50g of allyl isothiocyanate, adding 750g of water for dissolving, and uniformly stirring to obtain a second mixed solution;

Effect example 1

1. The target solutions of the pesticide compositions prepared in examples 1 to 13 were used for the cucumber powdery mildew test.

Referring to a biological measurement standard method NT/T1156.11-2008, a potting method is adopted.

Preparing a spore suspension: washing fresh spores on cucumber leaves full of powdery mildew with purified water containing a small amount of Tween80, filtering with double-layer gauze to obtain spores with concentration of 1 × 10 ⁵ spores/mL of suspension, ready for use.

The target solutions of the pesticide compositions prepared in examples 1 to 13 were uniformly prepared, sprayed on the leaves of the cucumber to be prepared until they were completely wetted, and after the liquid medicine was naturally air-dried, the prepared spore suspensions were spray-inoculated on the cucumber plants to be treated 24 hours after the treatment with the agent. For each 3 pots treated, 4 replicates were set. After the treatment of comparative example 1, a blank control was prepared. After inoculation, the mixture is placed in a greenhouse at the temperature of 25 +/-5 ℃ and the relative humidity of 70-90% for culture.

2. Data investigation and statistical analysis

1) Investigation method

When the blank control diseased leaf rate reaches more than 80%, investigating the diseased situation of each treatment in a grading way, wherein 36 leaves are investigated in each treatment, and the grading standard is as follows:

level 0: no disease;

level 1: the area of the lesion spots accounts for less than 5% of the area of the whole leaf;

and 3, level: the area of the lesion spots accounts for 5 to 15 percent of the area of the whole leaf;

and 5, stage: the area of the lesion spots accounts for 15 to 25 percent of the area of the whole leaf;

and 7, stage: the area of the lesion spots accounts for 25 to 50 percent of the area of the whole leaf;

and 9, stage: the area of the lesion spots accounts for 50 to 75 percent of the area of the whole leaf;

stage 11: the area of the lesion spots accounts for more than 75 percent of the area of the whole leaf.

According to the survey data, calculating the disease index of each treatment according to a formula (1) and calculating the prevention and treatment effect according to a formula (2).

In the formula: x represents disease index, Ni represents the number of diseased leaves at each level, i represents the relative level value, and N represents the total number of leaves investigated.

In the formula: p represents the prevention and treatment effect, CK represents the disease index of blank control, and PT represents the disease index of medicament treatment.

2) Method for evaluating synergistic effect

The synergistic effect of the mixed medicament is evaluated according to a co-toxicity coefficient method (CTC) of Sun & Johnson (1960) by referring to a biological test standard method NY/T1156.6-2006, namely that the CTC is not more than 80 as an antagonistic effect, the CTC is more than 80 and less than 120 as an additive effect, and the CTC is not less than 120 as the synergistic effect.

The Theoretical Toxicity Index (TTI) of the mixture is the toxicity index of the agent A x the percent (%) of the agent A + the toxicity index of the agent B x the percent (%) of the agent B

3) Statistical analysis of data

All experimental data were analyzed using SAS6.12 statistical software. Hyphal growth inhibition (%) was calculated from the test data, and virulence regression equation, correlation coefficient (r) and EC50 (95% confidence limit) were calculated.

3. Results analysis and discussion

1) Evaluation of drug efficacy in examples 1 to 5

The results of the synergistic effect evaluation of the combination of osthole and chitosan in different proportions on cucumber powdery mildew in examples 1-5 are shown in Table 1.

TABLE 1 indexes and control effects of osthole and chitosan mixed for cucumber powdery mildew

All the test data in table 1 were analyzed by SAS6.12 statistical software to obtain independent regression equation, correlation coefficient (r) and EC50 (95% confidence limit), co-toxicity coefficient, etc. of each treatment for cucumber powdery mildew, and the results are shown in table 2.

TABLE 2 toxicity test results of cucumber powdery mildew bacteria paired with osthole and chitosan

As shown in Table 2, the osthole and chitosan in examples 1-5 showed good inhibitory activity against cucumber powdery mildew in the mixed combinations of 1:1, 2:1, 3:1, 4:1 and 5:1, with EC50 values of 3.74, 3.82, 4.12, 3.93 and 5.06mg/L, co-toxicity coefficients of 142.93, 156.08, 153.57, 167.13 and 133.19, and co-toxicity coefficients (CTC) of more than 120, showing synergistic effect.

Wherein, the ratio of 4:1 has the best synergistic effect on cucumber powdery mildew.

2) Evaluation of drug efficacy in examples 6 to 13

The results of the synergistic effect evaluation of the combination of osthole, chitosan and allyl isothiocyanate in different ratios on powdery mildew of cucumber in examples 6-13 are shown in Table 3.

TABLE 3 indexes and control effects of osthole and chitosan mixture and allyl isothiocyanate on cucumber powdery mildew

All the test data in table 3 were analyzed using SAS6.12 statistical software to obtain values such as independent regression equation, correlation coefficient (r) and EC50 (95% confidence limit), co-toxicity coefficient, etc. for each treatment on cucumber powdery mildew, and the results are shown in table 4.

TABLE 4 determination of toxicity of osthole, chitosan and allyl isothiocyanate on cucumber powdery mildew

As is clear from Table 4, the combinations of osthole, chitosan and allyl isothiocyanate (1: 1:0.5, 1:1:1, 2:1:1, 3:1:1, 4:1:1 and 5:1:1, 4:1:0.5, 5:1: 0.5) of examples 6 to 13 exhibited good inhibitory activity against powdery mildew of cucumber, and their EC's were found to be ₅₀ The values are respectively 4.80, 4.64, 4.20, 5.40, 4.00, 5.60, 4.56 and 4.30mg/L, and the co-toxicity coefficients are respectively 155.80, 152.43, 157.28, 147.39, 187.31, 141.20, 156.70 and 150.60.

Wherein, the ratio of 4:1:1 has the best synergistic effect on cucumber powdery mildew.

Effect example 2

1. The target solutions of the pesticidal compositions prepared in examples 1 to 13 were used for the cucumber mildew test.

According to the agricultural industry standard NY/T1156.7-2006 of the people's republic of China, the method is carried out by adopting a pot cutting method.

The method comprises the following specific steps:

selecting diseased cucumber leaves, washing the leaf-carrying peronospora parasitica oocyst with partial steam at 4 ℃ to prepare a suspension, adjusting the concentration of the sporocyst to be about 2 x 10 sporocysts/mL, and storing at 4 ℃ for later use.

And then spraying the liquid medicine to the front and back sides of the cucumber leaves by using a sprayer until the front and back sides are wet, naturally drying the liquid medicine, and carrying out moisture-preserving culture for 24 hours and then inoculating. During inoculation, the ascocarp suspension is uniformly sprayed on the back of the leaves by a clean sprayer, and then the treated cucumber plants are cultured in a climatic chamber with a photoperiod (L: D ═ 12:12), a temperature of 22 ℃ and a relative humidity of 95%. After treatment of 5 pots each, 2 plants each, comparative example 1, a blank control was prepared.

2. Data investigation and statistical analysis

1) Investigation method

Each treated leaf was examined in stages according to the incidence of the blank control. Grading according to the following method:

no disease spot at level 0;

stage 1, the lesion area accounts for less than 5% of the whole leaf area;

grade 3, the lesion area accounts for 6 to 10 percent of the whole leaf area;

grade 5, the scab area accounts for 11 to 25 percent of the whole leaf area;

7, the lesion spot area accounts for 26 to 50 percent of the whole leaf area;

and 9, the lesion area accounts for more than 50 percent of the whole blade area.

And (4) calculating the disease index and the prevention and treatment effect of each treatment according to the investigation result and the formulas (3) and (4).

2) Data statistical analysis and synergy evaluation method

Performing statistical analysis by DPS software to obtain toxicity regression equation, and calculating EC of each agent ₅₀ 、EC ₅₀ And 95% confidence limits. The interaction of the mixture is calculated according to the method of Wadley, A, B represents two medicament components respectively, a and b are the percentage of the content of each component in the mixture, and the synergistic effect of the mixture is judged according to the SR value.

EC ₅₀ (theoretical value) ═ a + b)/(a/+ b/EC _50A +EC _50B )×100

SR＝EC ₅₀ (theoretical value)/EC ₅₀ (actual measurement value)

SR <0.5 is antagonism, SR <0.5 is additive action, and SR >1.5 is synergistic action.

3. Results analysis and discussion

1) Evaluation of drug efficacy in examples 1 to 5

The mixing combination of osthole and chitosan in different proportions in examples 1-5 is used for preventing and treating cucumber downy mildew, cucumber morbidity and preventing and treating effects are shown in Table 5.

TABLE 5 disease index and control effect of osthole and chitosan in different proportions on Pseudoperonospora cubensis

The data in the above table 5 are statistically analyzed by DPS software, and regression analysis and calculation are performed to obtain independent regression equation and EC of each treatment for cucumber downy mildew ₅₀ 、EC ₉₀ The values were equal and the results are shown in Table 6.

TABLE 6 virulence effects of osthole and chitosan on Pseudoperonospora cubensis

As can be seen from the results in Table 6, osthole and chitosan showed good inhibitory activities against Pseudoperonospora cubensis with EC ₅₀ The value was below 15 mg/L. Both of themAfter being mixed according to the proportion of 1:1, 2:1, 3:1, 4:1 and 5:1, the EC of each mixed combination for cucumber downy mildew ₅₀ The value is 10mg/L or less. The combined effect of each compatible combination on cucumber downy mildew is shown in Table 7.

TABLE 7 Combined action of osthole and chitosan in different ratios on Pseudoperonospora cubensis

Medicament	EC ₅₀ Theoretical value (mg/L)	EC ₅₀ Measured value (mg/L)	SR
				Comparative example 2	/	9.80	/
Comparative example 3	/	12.08	/
				Example 1	11.11	9.78	1.14
Example 2	10.72	7.54	1.42
				Example 3	10.51	5.93	1.77
Example 4	10.38	5.43	1.91
				Example 5	10.29	5.49	1.87

The results in Table 7 show that the SR value of the cucumber downy mildew is between 1.0 and 2.0 and no antagonism is generated after the osthole and the chitosan are mixed according to the proportion of 1:1, 2:1, 3:1, 4:1 and 5: 1.

The determination of a basin cutting method shows that the value of osthole to cucumber downy mildew is 9.80mg/L, and the value of chitosan is 12.08 mg/L; the formula screening test result shows that the ratio of osthole to chitosan is (1: 1) - (2): 1, the additive is shown in an additive effect; the cucumber propamonas are mixed within the range of 3: 1-5:1 to show a synergistic effect, wherein the synergistic effect of 4:1 on cucumber propamonas is the best.

2) Evaluation of drug efficacy in examples 6 to 13

The combination of osthole, chitosan and allyl isothiocyanate in different proportions in examples 6-13 is used for preventing and treating cucumber downy mildew, cucumber morbidity and control effects, and is shown in Table 8.

TABLE 8 evaluation data of different ratios of osthole, chitosan and allyl isothiocyanate for Pseudoperonospora cubensis

The data in the above table 8 are subjected to statistical analysis by using DPS software, and regression analysis and calculation are performed to obtain independent regression equation and EC of each treatment on cucumber downy mildew ₅₀ 、EC ₉₀ The values were equalized and the results are shown in Table 9.

TABLE 9 virulence effects of osthole, chitosan and allyl isothiocyanate on Pseudoperonospora cubensis

As can be seen from the results in Table 9, osthole, chitosan and allyl isothiocyanate showed good inhibitory activities against Pseudoperonospora cubensis with EC thereof ₅₀ The value was below 15 mg/L. The two are mixed according to the proportion of 1:1:0.5, 1:1:1, 2:1:1, 3:1:1, 4:1:1, 5:1:1, 4:1:0.5 and 5:1:0.5, and the mixed combination is used for treating the EC of cucumber downy mildew ₅₀ The value is 10mg/L or less. The combined effect of the combinations on cucumber downy mildew is shown in Table 10.

TABLE 10 Combined action of osthole, chitosan and allyl isothiocyanate on Pseudoperonospora cubensis

Medicament	EC ₅₀ Theoretical value (mg/L)	EC ₅₀ Measured value (mg/L)	SR
				Comparative example 2	/	9.80	/
Comparative example 3	/	12.08	/
				Comparative example 4	/	11.50	/
Example 6	12.16	10.48	1.16
				Example 7	11.60	9.63	1.21
Example 8	10.98	6.15	1.78
				Example 9	11.20	5.60	2.00
Example 10	10.10	5.20	1.94
				Example 11	9.20	7.80	1.18
Example 12	11.50	6.96	1.65
				Example 13	10.80	6.58	1.64

The results in Table 10 show that the SR value of the cucumber downy mildew bacteria is between 1.0 and 2.0 and no antagonism is generated after the osthole, the chitosan and the allyl isothiocyanate are mixed according to the proportion of 1:1:0.5, 1:1:1, 2:1:1, 3:1:1, 4:1:1, 5:1:1, 4:1:0.5 and 5:1: 0.5.

The determination of the pot cutting method shows that the value of osthole to cucumber downy mildew is 9.80mg/L, the value of chitosan is 12.08mg/L, and the value of allyl isothiocyanate is 11.50 mg/L; the formula screening test result shows that the osthole and the chitosan are mixed in the range of 1:1: 0.5-2: 1:1, and the additive effect is shown; the synergistic effect is shown by mixing in the range of 3:1: 1-5:1: 0.5. Wherein, the 4:1:1 ratio has the best synergistic effect on the cucumber peronospora parasitica.

The results show that the pesticide composition provided by the invention comprises osthole and chitosan, the osthole and the chitosan have synergistic bactericidal action in the composition, no antagonistic action exists, the bactericidal effect is superior to that of the single use of the osthole or the chitosan, and the osthole and the chitosan can show better synergistic action and have more superior bactericidal effect under the mass ratio of 4: 1. The composition can effectively kill powdery mildew and downy mildew of cucumber, effectively prevent and treat powdery mildew and downy mildew of cucumber, achieve ideal prevention and treatment effects, has no pollution to the environment, and is a safe and efficient botanical compound biological pesticide bactericide. And the effect is obviously better than that of the comparative example group.

The pesticide composition provided by the invention also comprises osthole, chitosan and allyl isothiocyanate, and the three are combined to show a synergistic effect. And when the mass ratio of osthole to chitosan to allyl isothiocyanate is 4:1:1, the synergistic effect is more remarkable, the bactericidal performance is more excellent, the bactericidal effect is more durable, the growth of fungi can be inhibited for a long time, and the pesticide is used as a pesticide, has less pesticide residue in fruits and vegetables and has high safety to human bodies. And the effect is obviously better than that of the comparative example group.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents or improvements made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A pesticide composition is characterized by comprising osthole and chitosan; wherein the mass ratio of the osthole to the chitosan is 1-5: 1.

2. The pesticide composition as set forth in claim 1, wherein the mass ratio of the osthole to the chitosan is 1-4: 1.

3. The pesticide composition as set forth in claim 2, wherein the mass ratio of the osthole to the chitosan is 4: 1.

4. The pesticidal composition according to claim 1, characterized by further comprising: allyl isothiocyanate; wherein the weight ratio of the osthole to the chitosan to the allyl isothiocyanate is 1-5:1: 0.5-1.

5. The pesticidal composition according to claim 4, characterized in that the mass ratio of the osthole, the chitosan and the allyl isothiocyanate is 1-4:1: 0.5-1.

6. The pesticidal composition according to claim 5, characterized in that the mass ratio of the osthole, the chitosan and the allyl isothiocyanate is 4:1: 1.

7. The pesticidal composition according to any one of claims 1 to 6, characterized by further comprising a solubilizer, a thickener and an emulsifier;

wherein the solubilizer comprises any one of the following: n-methyl pyrrolidone, polyethylene glycol or propylene glycol;

the thickener comprises any one of the following substances: hydroxymethyl cellulose, alkyl polyglycoside or polyacrylic acid;

the emulsifier comprises any one of the following components: c13 nonionic half-branched fatty alcohol-polyoxyethylene ether, phosphate ester or alkylphenol ethoxylate.

8. The pesticide combination solution is characterized by comprising the following components in percentage by mass:

10-25% of osthole, 4-13% of chitosan, 8-10% of N-methyl pyrrolidone, 50-55% of water, 1-4% of alkyl polyglycoside and 3-6% of C13 nonionic half-branched fatty alcohol polyoxyethylene ether; or

10-25% of osthole, 4-13% of chitosan, 4-10% of allyl isothiocyanate, 8-10% of N-methylpyrrolidone, 50-55% of water, 1-4% of alkyl polyglycoside and 3-6% of C13 nonionic half-branched fatty alcohol polyoxyethylene ether.

9. The method for preparing a pesticidal composition according to claim 8, wherein when the ingredients do not contain allyl isothiocyanate, the method comprises the steps of:

adding the chitosan into the residual water to obtain a second mixed solution;

adding the C13 nonionic half-branched fatty alcohol-polyoxyethylene ether and alkyl polyglycoside into the third mixed solution, and uniformly stirring until the mixture is clear to obtain the composite material;

10. Use of the pesticidal composition of any one of claims 1 to 7 or the pesticidal composition of claim 8 for controlling cucumber powdery mildew and downy mildew.