阅读说明：本技术 一种复配杀菌组合物及其应用 (Compound bactericidal composition and application thereof ) 是由 卢晓红 高毓晗 李世东 孙漫红 于 2020-12-31 设计创作，主要内容包括：本发明涉及一种复配杀菌组合物及其应用,所述复配杀菌组合物包含粉红螺旋聚孢霉孢子和咯菌腈,其中,所述粉红螺旋聚孢霉孢子粉与所述咯菌腈的重量比为90～99.98：0.02～10。本发明所提供的复配杀菌组合物适用于防治齐整小核菌引起的作物病害,诸如辣椒白绢病,可作保护地土壤处理；防治效果较单剂有明显提升,用量相对较少,可降低用药成本,并降低对土壤环境的污染。(The invention relates to a compound bactericidal composition and application thereof, wherein the compound bactericidal composition comprises spirosporium roseum spores and fludioxonil, wherein the weight ratio of the spirosporium roseum spore powder to the fludioxonil is 90-99.98: 0.02 to 10. The compound bactericidal composition provided by the invention is suitable for preventing and treating crop diseases caused by sclerotinia rolfsii, such as southern blight of pepper, and can be used for soil treatment of protected areas; compared with single agent, the control effect is obviously improved, the dosage is relatively less, the medication cost can be reduced, and the pollution to the soil environment is reduced.)

1. A compound sterilization composition is characterized by comprising Sporotrichum roseum spores and fludioxonil.

Wherein the weight ratio of the spirosporium roseum spore powder to the fludioxonil is 90-99.98: 0.02 to 10.

2. The compound bactericidal composition as claimed in claim 1, wherein the spore content of the spirospora rosea spore powder is 1 x 10⁸～8×10⁸CFU/g。

3. The compound sterilization composition according to claim 1 or 2, wherein the weight ratio of the spirosporium roseum spore powder to fludioxonil is 99-99.98: 0.02 to 1;

wherein the preferable spore content of the Sporosporium roseum in the Sporosporium roseum powder is 2.5 multiplied by 10⁸～3.5×10⁸CFU/g。

4. The compound sterilization composition according to claim 1 or 2, wherein the weight ratio of the spirosporium roseum spore powder to fludioxonil is 90.93-99.94: 0.06 to 0.07.

5. The compound bactericidal composition according to any one of claims 1 to 4, wherein the formulation is a wettable powder.

6. The compound sterilization composition according to claim 5, which is prepared from the following components in percentage by mass of 99-99.98: 0.02-1 of wettable powder of spirospora rosea spores and wettable powder of fludioxonil;

wherein, the content of the traditional Chinese medicine in the fludioxonil wettable powder is 45-55%.

7. The compound bactericidal composition as claimed in claim 6, wherein the wettable powder further comprises an auxiliary material.

8. The application of the compound bactericidal composition as defined in any one of claims 1 to 7 in controlling soil-borne diseases of crops caused by sclerotinia rolfsii.

9. The application of the compound bactericidal composition as claimed in claim 8, wherein the application modes of the compound bactericidal composition comprise foliar spraying, soil mixing, root irrigation and seed treatment;

preferably, the wettable powder is prepared according to the weight ratio of 1: mixing 100-300 parts by weight of the composition with water, and then applying the composition.

10. The use according to claim 9, wherein the crop soil-borne disease is southern blight.

Technical Field

The invention relates to a compound bactericidal composition and application thereof, in particular to a compound bactericidal composition containing spirospora rosea spores and fludioxonil and application thereof.

Background

The chemical prevention and control dosage of the plant soil-borne diseases is large, especially the residue is seriously exceeded due to the overdose use of a protected land, and pathogenic bacteria generate drug resistance. The biological control is environment-friendly, the bacterial-pesticide composite agent mixed by the biocontrol bacteria and the chemical pesticide can improve the control effect of the biological control and reduce the application amount of the chemical pesticide in the disease control, is expected to avoid the generation of drug resistance of plant pathogenic bacteria, and obtains stable and lasting control effect. Therefore, the chemical and biological synergistic control of plant diseases is concerned more and more, the chemical and biological synergistic control of plant diseases is beneficial to food safety, environmental protection and agricultural sustainable development, and the development of the bacterial-drug complexing agent is supported by national policies more and more.

The southern blight of the pepper is taken as a soil-borne disease in the world, and the disease is particularly serious in the production area of the pepper in south China, so that the yield and the output value of the pepper are influenced. The pathogenic bacteria of the southern blight of the pepper is sclerotinia rolfsii (Sclerotium rolfsii), the host range of the Sclerotium rolfsii is wide, and the Sclerotium rolfsii can infect more than 100 families and more than 500 plants, mainly comprising crops such as pepper, tomato, eggplant, peanut and the like. The southern pepper sclerotium fungi are in common asexual generations in the field, do not produce spores, but can form smooth and glossy sclerotia. The sclerotium can live through the winter in soil or in seeds, and has strong adaptability and long survival time. The sclerotia and mycelium remaining in the soil and the diseased residues are the main primary sources of infection, which mainly infect the basal part of the plant stem and the roots near the ground, causing the cortex to be rotten, and interrupting the delivery of water and nutrients, resulting in the withering and death of the plant. At present, because of the factors of wide host range of pathogenic bacteria, lack of effective disease-resistant varieties, insufficient popularization of agricultural technology and the like, a plurality of difficulties exist in disease control.

Sporotrichum roseum: belonging to Ascomycota (Ascomycota), Hypocrea (Hypocrea), Chitosaceae (Bionectriaceae), Sporotrichum (Clonostachys) and being a beneficial fungus with high biocontrol value. The microbial fertilizer is widely distributed in soil and environment, can parasitize various plant pathogenic bacteria, has the characteristics of quick propagation, strong adaptability and wide antimicrobial spectrum, and also has the effects of promoting plant growth, inducing plant disease resistance and promoting seed germination. It can prevent and control several plant pathogenic fungi by means of a series of mechanisms of heavy parasitism, production of resistant substance, competitive action, production of degradation enzyme and induction of plant resistance.

Fludioxonil, common english name: fludioxonil, chemical name: 4- (2, 2-difluoro-1, 3-benzodioxol-4-yl) pyrrole-3-carbonitrile; the molecular formula is as follows: c₁₂H₇N₂O₂F₂(ii) a It is an analogue of the secondary metabolite, nitropyrrolidin (pyrrolnitin), produced by Pseudomonas pyrrociniaThe product, but is resistant to photolysis compared with natural product nitropyrrolidin, is a high-efficiency, broad-spectrum, low-toxicity, low-residue and non-systemic phenylpyrrole bionic bactericide. Fludioxonil has the characteristics of good control effect, long lasting period, safe use and the like on various plant fungal diseases. The sterilization mechanism of fludioxonil to botrytis cinerea mainly interferes and destroys the biological oxidation and biosynthesis process of botrytis cinerea; the bacteriostatic mechanism of fludioxonil is to inhibit the growth of hyphae by inhibiting the transport related to the phosphorylation of glucose, and finally, the death of the pathogenic bacteria is caused. Fludioxonil has a very good effect of preventing seed-borne and soil-borne diseases caused by many pathogenic bacteria such as ascomycetes, basidiomycetes, imperfect fungi and the like, such as sweet melon fusarium wilt, loose smut, stinking smut, banded sclerotial blight, stem blight and the like. Fludioxonil is widely used in various crops, such as cotton, wheat, peanut, soybean, rice, melon, etc.

Disclosure of Invention

The invention aims to solve the technical problem of providing a compound bactericidal composition containing spirosporium roseum spores and fludioxonil, which is efficient, safe, low in toxicity, long in lasting period and beneficial to comprehensive treatment of diseases.

Specifically, the compound bactericidal composition comprises the spirosporium roseum spore powder and fludioxonil.

The weight ratio of the spirosporium roseum spore powder to the fludioxonil is 90-99.98: 0.02-10;

wherein the spore content in the Sporosporium roseum powder is 1 × 10⁸～8×10⁸CFU/g。

As known in the art, most chemical bactericides can achieve a better bactericidal effect when the dosage is large; in the previous development process, the inventor of the invention finds that the spirosporium roseum spore has excellent bactericidal effect. However, when the spirosporium roseum spores are compounded with a common chemical bactericide, the compatibility is very poor; the compound bactericidal composition provided by the invention is based on the spirospora rosea spores and is compounded with a specific chemical bactericide. The two compositions have good compatibility and can greatly improve the sterilization effect under the combination of specific proportions. The sterilization effect of the two is obviously greater than that of the spirosporium roseum spore and fludioxonil; in addition, the chemical bactericide is very small in using amount, and can effectively avoid the influence of chemical reagents on the environment in actual field use.

Preferably, the weight ratio is 99-99.98: 0.02-1; the dosage of the adopted chemical bactericide is not more than 1 percent, the obtained bactericidal effect is more excellent, and the bactericide dosage is better. More preferably, when the weight ratio of the spirosporium roseum spore powder to the fludioxonil is 90.93-99.98: 0.02-0.07; particularly, when the weight ratio is 90.93-99.94: 0.06-0.07, the complementary effect of the two components is optimal.

Wherein the preferable spore content of the Sporosporium roseum in the Sporosporium roseum powder is 2.5 multiplied by 10⁸～3.5×10⁸CFU/g。

The spirillum roseum spore powder provided by the invention is obtained by liquid fermentation, adsorption and drying in the conventional mode in the field.

Preferably, the formulation of the compound bactericidal composition is wettable powder. The spirosporium roseum spore powder and fludioxonil are directly mixed in wettable powder; the powder is not only simple to operate in the preparation process; the subsequent field application operation is also simple and convenient; in addition, the wettable powder provided by the invention can still keep a better sterilization effect in the long-time storage process.

Wherein, the content of original medicine (fludioxonil) in the fludioxonil wettable powder is 45-55%.

Preferably, the wettable powder also comprises an auxiliary material; the adjuvants are not limited to dispersants, stabilizers, wetting agents, carriers, and the like.

The compound sterilization composition containing the spirospora rosea spores and fludioxonil can be widely applied to prevention and treatment of soil-borne diseases such as capsicum southern blight and the like caused by sclerotinia rolfsii.

The application mode of the compound bactericidal composition comprises foliar spraying, soil mixing, root irrigation and seed treatment.

In particular, the crop soil-borne disease is southern blight.

In the application process, the wettable powder is prepared according to the weight ratio of 1: diluting the mixture in water at a weight ratio of 100-300, and then applying the mixture.

The compound bactericidal composition of the spirosporium roseum spores and the fludioxonil provided by the invention at least has the following beneficial effects:

1. the provided compound bactericidal composition is suitable for preventing and treating crop diseases caused by sclerotinia rolfsii, such as southern blight of pepper, and can be used for soil treatment of protected areas;

2. compared with a single agent, the compound bactericidal composition has obviously improved control effect and relatively less dosage, can reduce the medication cost and reduce the pollution to the soil environment.

3. The product has a longer shelf life.

Detailed Description

The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

The fermentation broth of the Sporotrichum roseum is obtained by the steps of fermenting and drying Sporotrichum roseum spores in the following examples; sporotrichum roseum (China general microbiological culture Collection center, accession number CGMCC No. 1037).

Example 1

The embodiment provides a compound bactericidal composition, which consists of 9:1 mass percent of wettable powder of spirospora rosea spores and wettable powder of fludioxonil;

wherein, the content of the traditional Chinese medicine in the fludioxonil wettable powder is 50 percent;

wherein the content of spores in the wettable powder of the spirospora rosea spores is 1 multiplied by 10⁸CFU/g。

Example 2

The embodiment provides a compound sterilization composition, which is different from embodiment 1 in that the compound sterilization composition consists of 99.98:0.02 mass percent of wettable powder of spirillaria rosea spores and fludioxonil, wherein the content of spores in the wettable powder of the spirillaria rosea spores is 3 x 10⁸CFU/g。

Example 3

The embodiment provides a compound sterilization composition, which is different from the embodiment 1 in that the compound sterilization composition consists of 99.93:0.07 mass percent of wettable pink spirosporium spore powder and wettable fludioxonil powder; wherein the content of spores in the wettable powder of the spirospora rosea spores is 3 multiplied by 10⁸CFU/g。

Comparative examples 1 to 2

The comparative example provides a compound bactericidal composition, and the difference from the example 1 is only that the fludioxonil is replaced by the kresoxim-methyl and the fluazinam.

Test example 1

The biocompatibility of the spirospora rosea spores, the compound bactericidal composition provided by the embodiment 1 and the comparative examples 1-2 is measured.

(1) Growth of Sporotrichum roseum spores (HDL-1 conidia) in PDB-containing medium

mu.L of Spirospira rosea HDL-1 spore suspension (1X 10)⁶CFU/mL) is added into 100mL of PDB culture medium containing medicine (the concentration of the effective components of the chemical bactericide is 100 mu g/mL), shaking culture is carried out for 7d at the temperature of 25 ℃ at 120r/min, the dry weight of the thalli in the PDB is measured, the inhibition rate is calculated, and PDB culture medium without medicine is used as CK control.

Inhibition ratio (dry weight of CK cells-dry weight of treated cells)/dry weight of CK cells × 100%

(2) Growth of HDL-1 conidia on PDA medium containing medicine

The preparation method of the drug-containing culture medium plate is the same as the above, wherein the effective concentration of fludioxonil is 100 mug/mL and 500 mug/mL respectively. mu.L of Spirospira rosea HDL-1 spore suspension (1X 10)⁶CFU/mL) was uniformly coated on a drug-containing plate, cultured at 27.8 ℃ with a drug-free medium as a control, and the number of colonies on the drug medium was measured after 72 hours to calculate the bacteriostatic rate.

TABLE 1 Effect of test Agents on the amount of HDL-1 growth in PDB Medium

TABLE 2 Effect of fungicides on HDL-1 conidia Activity on PDA Medium

Name of medicament	Effective concentration (μ g/mL)	Colony count (dish/piece)	Inhibition ratio (%)
				Fludioxonil	100	123±9	-7.96
Control	—	114±4	0.00

Note: the data in the table are mean ± standard deviation.

The results show that: (Table 1) in the liquid culture medium containing 100 mug/mL of the chemical bactericide, the chemical bactericide has the effect of inhibiting the biomass of the biocontrol bacterium HDL-1, but the inhibition effect has large difference. Wherein the inhibition effect of fludioxonil on the biocontrol bacterium HDL-1 is small, and the inhibition rate is 6.35%. The biocontrol bacterium HDL-1 spore can normally germinate and grow on a drug-containing culture medium with the concentration of fludioxonil of 100 mu g/mL, which indicates that the fludioxonil has no inhibiting effect on the germination and colony formation of the HDL-1 conidium.

Test example 2

And (3) determining the control effect of the compound bactericidal composition, the suspension of the spirillospora rosea spores and the fludioxonil on the pathogenic bacteria of the southern blight of the capsicum.

Preparing fludioxonil into a drug-containing culture medium: diluting fludioxonil with sterile water into liquid medicines with different concentration gradients of 0.0. mu.g/mL, 200. mu.g/mL, 700. mu.g/mL and the like, adding 60. mu.L of the liquid medicine into 60mL of PDA culture medium, shaking uniformly, and pouring into four sterile culture dishes on average. The sclerotium treatment method is the same as above (collecting mature sclerotium from PDA plate, adding into 1% sodium hypochlorite solution for sterilization, washing with sterile water three times, soaking in HDL-1 spore suspension (1 × 10)⁶CFU/mL) for 5min), 10 sclerotia are connected to each drug-containing plate, and the germination of sclerotia is observed after 4 days. The method comprises the following specific steps:

(1) example 2 provides an inhibitory effect of a formulated fungicidal composition on sclerotium germination

(2) Example 3 provides an inhibitory effect of the complex fungicidal composition on sclerotium germination

(3) Inhibition of sclerotium germination by 0.02 ‰ fludioxonil (200 μ g/mL)

(4) Inhibition of sclerotium germination by 0.07 ‰ fludioxonil (700 μ g/mL)

(5) Gliocladium roseum (3X 10)⁸CFU/g) inhibiting sclerotium germination

(6) Germination of untreated sclerotia

Table 3: influence of different proportions of fludioxonil and gliocladium roseum on sclerotium germination of sclerotium of capsicum annuum

Serial number	Germination number (granule)	Inhibition ratio (%)
			(1)	8	11.76
(2)	2	76.47
			(3)	9	10.00
(4)	10	0.00
			(5)	10	0.00
(6)	10	0.00

The results show that: (Gliocladium roseum) HDL-1 strain has inhibitory effect on sclerotium germination; the bactericide has almost no inhibition effect on sclerotium germination, but can inhibit the growth of hyphae; the application of the fungus medicine compound composition has a synergistic and complementary effect; in particular to the compound sterilization composition provided by the embodiment 3.

Test example 3

The shelf life of the compound bactericidal composition provided in example 1 was measured.

The shelf life of a mixed microbial agent (example 1) prepared by mixing the fludioxonil wettable powder serving as a chemical fungicide and the Spirosporium roseum HDL-1 spore wettable powder was determined.

The product is stored at normal temperature, and meanwhile, the Sporostachys rosea spore powder (ck) without chemical bactericide is used as a control. The survival status of HDL-1 conidia in the mixed preparation is determined by dilution coating method at 0d, 15d, 57d, 109d and 168d, four replicates are set for each treatment and each experiment is cultured at 27.8 ℃, and after 3d, the bacterial mixture is observed and subjected to colony counting method, and the shelf life of the bacterial medicine mixed preparation is determined according to the content of active spores.

Table 4: HDL-1 active conidium content in the mixed preparation after storing for different time

The results show that: the active conidium content decreases overall with increasing storage time. The number of the active spores of the spirillum roseum in the bacterial mixture is obviously reduced after 109 days, but the number of the active spores is still more than 2 x 10 after 168 days⁸CFU/g, and not much different from the control. Therefore, the shelf life of the mixed bacteria and medicine can reach about 6 months.

Although the invention has been described in detail hereinabove by way of general description, specific embodiments and experiments, it will be apparent to those skilled in the art that many modifications and improvements can be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.