CN112772655A

CN112772655A - Nano sulfur compound medicament and application thereof

Info

Publication number: CN112772655A
Application number: CN202110031333.0A
Authority: CN
Inventors: 牟文君; 宋纪真; 何伟; 李菁菁; 龙腾; 陈善义; 姜振锟; 王爱国; 胡利伟; 王桂瑶; 奚家勤; 过伟民
Original assignee: China Tobacco Fujian Industrial Co Ltd; Zhengzhou Tobacco Research Institute of CNTC
Current assignee: China Tobacco Fujian Industrial Co Ltd; Zhengzhou Tobacco Research Institute of CNTC
Priority date: 2021-01-11
Filing date: 2021-01-11
Publication date: 2021-05-11
Also published as: CN113767920A; CN113767920B

Abstract

The invention belongs to the field of bactericides and particularly relates to a nano sulfur compound medicament and application thereof. The active ingredients of the nano sulfur compound medicament consist of one of dimoxystrobin and fluazinam and nano sulfur; the mass ratio of the dimoxystrobin to the nano sulfur is 1: (20-80); the mass ratio of the fluazinam to the nano sulfur is 1: 40. The bisphenylamine and fluazinam of the nano-sulfur compound medicament have oxidative phosphorylation uncoupling activity, the nano-sulfur has the characteristics of small particles, strong permeability, high diffusivity and the like, and the nano-sulfur are compounded in a certain proportion, so that the nano-sulfur compound medicament has a synergistic effect in the aspect of bacterial wilt prevention and control.

Description

Nano sulfur compound medicament and application thereof

Technical Field

The invention belongs to the field of bactericides and particularly relates to a nano sulfur compound medicament and application thereof.

Background

Bacterial Wilt of plants (Bacterial wild) is a devastating soil-borne vascular bundle disease caused by Ralstonia solanacearum, with a wide distribution of pathogenic bacteria that can infect hundreds of crops in more than 50 families, such as tobacco, tomato, potato, etc. (Middleton and Hayward, 1990, sio et al, 2012). Ralstonia solanacearum is infected from the root or wound of a plant, invades xylem vascular bundles and quickly enters the overground part of the plant through the vascular system, and particularly serious harm is caused to solanaceae crops. Tobacco is an important economic crop in China, the speed of tobacco bacterial wilt running and spreading is accelerated along with the continuous cropping age of tobacco fields in recent years, the disease rate of serious fields reaches 100%, and the tobacco bacterial wilt running and spreading is one of the main diseases of tobacco production.

The ralstonia solanacearum has higher genetic variability and environmental adaptability, has complex bacterial systems, is seriously harmful and difficult to prevent and treat, is an important limiting factor in tobacco production, and effective prevention and treatment measures of the ralstonia solanacearum are always key and difficult points in production. At present, the control of bacterial wilt in production mainly adopts comprehensive measures of combining agricultural control, biological control and chemical control. Because different control methods have limitations or restrictions and bacterial wilt is often mixed with fungal and oomycete diseases, no effective measure is provided for controlling bacterial wilt.

The chemical agents play irreplaceable important roles in the prevention and treatment of the diseases by virtue of the characteristics of high efficiency and quick acting, but the currently registered agents for the prevention and treatment of the bacterial wilt only comprise 8 non-high-efficiency agents except biocontrol bacteria, wherein the agents mainly comprise zhongshengmycin, thiediazole copper, chloropicrin, thienconcopper, chlorourea, copper sulfate, trichloroisocyanuric acid, metalaxyl, hymexazol and metalaxyl, thiram and thiram, and the varieties of the agents are very limited (Chinese pesticide information network, Zhang Hao, 2018).

The nano pesticide has the characteristics of small particles, strong permeability, high diffusivity and the like, has higher effective rate and longer lasting period compared with the traditional pesticide, and has certain application in pesticide decrement and synergism. The Chinese patent application with the application publication number of CN111109295A discloses a pesticide composition with kasugamycin and nano-silver as active components (effective ingredients), which is mainly used for preventing and treating citrus canker. At present, effective chemical agents are still lacking in the aspect of bacterial wilt prevention and control.

Disclosure of Invention

The invention aims to provide a nano sulfur compound medicament which can effectively prevent and treat bacterial wilt.

The second purpose of the invention is to provide the application of the medicament in preventing and controlling bacterial wilt of plants.

In order to achieve the aim, the technical scheme of the nano sulfur compound medicament is as follows:

a nanometer sulfur compound preparation comprises effective components of one of dimoxystrobin and fluazinam and nanometer sulfur; the mass ratio of the dimoxystrobin to the nano sulfur is 1: (20-80); the mass ratio of the fluazinam to the nano sulfur is 1: 40.

Preferably, the mass ratio of the fenazamide to the nano sulfur is 1: (20-70), 1: (20-60), 1: (20-50), 1: (20-40), more preferably 1: (30-40).

Fluazinam is a protective bactericide (Anema et al, 1992) developed by Japan stone Prov. corporation, is a representative medicament in pyridinamine compounds, is high-efficiency and low-toxicity, has a wide control spectrum, is registered as a pesticide in China in 2008, and has good bacteriostatic activity and control effect on most phytopathogens and mites of phytopathogens such as phytophthora parasitica, plasmodiophora and anophomycetes and sexless fungi (Matheron and Porchs, 2000, Donald et al, 2001, the Muwenjun et al, 2018).

Since the fluazinam was put into production in the last 80 th century, no field strain which can generate resistance to fluazinam alone is found, and the existing research shows that the drug resistance of plant pathogenic fungi to fluazinam develops slowly. Fluazinam has no interactive resistance with bactericides with other action mechanisms, and can be used for treating the existing resistance risk (Korolev et al, 2011, Ziogas et al, 2006, Kalamarakis et al, 2000). The registered targets of fluazinam in China are pepper phytophthora blight, potato late blight and Chinese cabbage clubroot, the target control, the use frequency and the control area of fluazinam are gradually increased year by year in China and the world in recent years, but the fluazinam mainly takes fungi and oomycetes and is not applied to the control of bacterial diseases.

The dianilinosamine (SYP-14288) belongs to diarylamine compounds, is a novel compound independently researched and developed by Shenyang chemical research institute in China, has oxidative phosphorylation uncoupling activity similar to that of fluazinam, and has excellent bacteriostatic action on most pathogenic fungi (Nixian et al, 2012).

The bisphenylamine and fluazinam of the nano-sulfur compound medicament have oxidative phosphorylation uncoupling activity, the nano-sulfur has the characteristics of small particles, strong permeability, high diffusivity and the like, and the nano-sulfur are compounded in a certain proportion, so that the nano-sulfur compound medicament has a synergistic effect in the aspect of bacterial wilt prevention and control.

Preferably, the particle size of the nano sulfur is 7 nm.

On the basis of the above active ingredients, a formulation acceptable for agricultural chemicals can be prepared according to a technique known in the art. Preferably, the preparation formulation is water dispersible granules, wettable powder, suspending agent, missible oil, aqueous emulsion or microemulsion.

The mass content of the effective components in the preparation can be 0.5-90% of the total mass of the preparation.

In the above-mentioned dosage forms, in addition to the above-mentioned active ingredients, one or more agriculturally pharmaceutically acceptable adjuvants and other substances useful for stably exerting the drug effect of the active ingredients in the formulations are generally used, and these substances are various ingredients commonly used or allowed to be used in the formulation of agricultural chemicals. The auxiliary agent comprises wetting dispersant, stabilizer, antifreeze, disintegrant, thickener, defoamer, organic solvent, carrier and the like, and the specific selection and dosage of the auxiliary agent can be determined by routine tests according to the formula requirements. Alternative varieties of adjuvants are exemplified below. Specifically, the method comprises the following steps:

the wetting dispersant can be selected from one or more of sodium dodecyl sulfate, calcium lignosulfonate, alkylphenol polyoxyethylene formaldehyde condensate, polyoxyethylene lauryl sulfate sodium, nekal, polyoxyethylene lauryl phosphate, hydroxymethyl cellulose and the like.

The stabilizer can be one or more of citric acid, epoxidized soybean oil, sodium sorbate, butyl glycidyl ether, phenyl glycidyl ether, dinaphthol, mononaphthol and the like.

The antifreeze can be any one of glycerol, propylene glycol, ethylene glycol, urea, sodium chloride and the like.

The disintegrating agent can be selected from one or more of ammonium sulfate, calcium chloride, bentonite, ammonium dihydrogen phosphate, etc.

The thickener can be one or more selected from xanthan gum, arabic gum, soluble starch, sucrose, glucose, sodium alginate, acrylic polymer, soybean protein, dextrin, silicic acid, magnesium aluminum silicate, etc.

The defoaming agent can be any one of silicone oil defoaming agent, silicone defoaming agent and the like.

The organic solvent may be selected from one or more of isopropanol, butanol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, glycerol, sorbitol, benzyl alcohol, vegetable oil, etc.

The carrier can be selected from one or more of diatomite, talc, bentonite, kaolin, white carbon black, calcite, attapulgite and the like.

The application of the nano sulfur compound medicament in the aspect of preventing and treating bacterial wilt of plants.

Experiments prove that the bactericide has a synergistic control effect on tobacco bacterial wilt caused by ralstonia solanacearum, and is beneficial to reduction and efficient use of pesticides.

Drawings

FIG. 1 is a growth curve of Ralstonia solanacearum in the experimental example of the present invention;

FIG. 2 is a graph showing a baseline of the sensitivity of Ralstonia solanacearum to fluazinam in the experimental examples of the present invention;

FIG. 3 is a graph showing the sensitivity baseline of Ralstonia solanacearum to dimoxystrobin in the experimental examples of the present invention.

Detailed Description

The following examples are provided to further illustrate the practice of the invention. In the following examples, fluazinam (98% active ingredient), purchased from Shanghai assist, trade, Inc. The concentration of the nano copper solution, the nano silver solution and the nano sulfur solution is 10³mu.g/mL, all available from New nanocrystal materials, Wisco.

The dimethyl sulfoxide for fluazinam is configured into 10⁵mu.g/mL of the mother liquor was stored at 4 ℃.

Diphenylamine (98% active ingredient) was purchased from Shenyang chemical research institute. The dimethyl sulfoxide for the dianisidine is prepared into 10⁵mu.g/mL of the mother liquor was stored at 4 ℃.

The kasugamycin is prepared with sterilized water with the concentration of 10⁴mu.g/mL of the mother liquor. Thiomycinone is prepared with dimethyl sulfoxide to 10⁵mu.g/mL of the mother liquor.

The experimental agents with different concentrations in the following examples were all obtained by diluting the mother liquor with solvent. Wherein, the fluazinam, the dimoxystrobin and the benziothiazolinone solution are diluted by dimethyl sulfoxide, and the kasugamycin solution is diluted by sterilized water.

First, specific embodiment of the nano sulfur compound medicament of the invention

Example 1

The nano sulfur compound medicament of the embodiment is prepared by compounding fluazinam solution with the concentration of 0.5 mug/mL and nano sulfur solution with the concentration of 0.5 mug/mL according to the volume ratio of 1: 40.

The fluazinam solution with the concentration of 0.5 mug/mL is prepared from 10⁵Mu g/mL of fluazinam mother liquor and dimethyl sulfoxide.

The nano sulfur solution with the concentration of 0.5 mug/mL is prepared from the nano sulfur solution with the concentration of 10³The micro g/mL nano sulfur solution and the sterilized water.

The density of the two solutions can be calculated according to 1g/ml, and the mass ratio of the fluazinam to the nano sulfur is 1:40 after the mass conversion. The following examples are all converted in this manner.

Example 2

The nano sulfur compound medicament is prepared by compounding a fluazinam solution with the concentration of 2 mug/mL and a nano sulfur solution with the concentration of 2 mug/mL according to the volume ratio of 1: 40.

Example 3

The nano sulfur compound medicament is prepared by compounding a fluazinam solution with the concentration of 4 mug/mL and a nano sulfur solution with the concentration of 4 mug/mL according to the volume ratio of 1: 40.

Example 4

The nano sulfur compound medicament is prepared by compounding 8 mug/mL fluazinam solution and 8 mug/mL nano sulfur solution according to the volume ratio of 1: 40.

Example 5

The nano sulfur compound medicament is prepared by compounding a fluazinam solution with the concentration of 16 mug/mL and a nano sulfur solution with the concentration of 16 mug/mL according to the volume ratio of 1: 40.

Example 6

The nano sulfur compound medicament is prepared by compounding a fluazinam solution with the concentration of 40 mug/mL and a nano sulfur solution with the concentration of 40 mug/mL according to the volume ratio of 1: 40.

Example 7

The nano sulfur compound medicament is prepared by compounding a dianiline solution with the concentration of 0.04 mug/mL and a nano sulfur solution with the concentration of 0.04 mug/mL according to the volume ratio of 1: 20.

On the basis of the embodiment, the concentration of the dianiline solution and the concentration of the nano sulfur solution are controlled to be equal, the concentration is adjusted to be 0.1, 1, 5 and 10 mu g/mL, and the corresponding compound medicament can be obtained by compounding according to the volume ratio of 1: 20.

Example 8

The nano sulfur compound medicament of the embodiment is different from the embodiment 7 only in that the compound volume ratio of the dimoxystrobin solution to the nano sulfur solution is 1: 40.

Example 9

The nano sulfur compound medicament of the embodiment is different from the embodiment 7 only in that the compound volume ratio of the dimoxystrobin solution to the nano sulfur solution is 1: 80.

Example 10

The nano sulfur compound medicament is prepared from the following raw materials in parts by mass: 1% of fluazinam, 40% of nano-sulfur, 10% of ammonium sulfate, 2.5% of alkylphenol polyoxyethylene, 3% of sodium dodecyl benzene sulfonate, 4% of fatty acid polyoxyethylene ester and the balance of light calcium carbonate to 100%.

Accurately taking the raw materials according to the mass parts, uniformly mixing, and then carrying out high-speed shearing, grinding, granulating, drying and sieving to prepare the water dispersible granules.

Example 11

The nano sulfur compound medicament is prepared from the following raw materials in parts by mass: 1% of fluazinam, 40% of nano sulfur, 5% of sodium lignosulfonate, 5% of alkyl naphthalene sulfonate, 1% of polyvinyl alcohol, 0.5% of ethylene glycol and the balance of water to 100%.

Accurately taking the raw materials according to the mass parts, fully mixing and grinding the raw materials until the diameter of the medicament particles is less than or equal to 5 mu m to obtain the suspending agent.

Example 12

The nano sulfur compound medicament is prepared from the following raw materials in parts by mass: 1% of dimoxystrobin, 20% of nano-sulfur, 18% of dimethylbenzene, 406% of tween-ethylene glycol, 4% of organic silicon and the balance of water to 100%.

Accurately taking the raw materials according to the parts by weight, and fully mixing and stirring to prepare the aqueous emulsion.

Second, please refer to the experimental example section for the application of the nano sulfur compound medicament of the present invention.

Third, Experimental example

In the following experimental examples, tobacco strains with bacterial wilt disease in tobacco fields suitable for yellow, Li Chuan, le' an, Guangchang, Yangxi, Nanfeng and Chong ren disease in the province, respectively, were collected, isolated, cultured and identified to be Ralstonia solanacearum. The geographical source of the isolated ralstonia solanacearum is 2 strains in Chongren county Fenggang village; li Chuan county 4 plants from Deshengxiang, Hufangxiang, Tan xi county; 5 Yihuang county plants from Huang Town and Didu Town respectively; 9 strains in Guangchang county are collected from the head and the town, the river and the town and the Changqiao county; the 10 Nanfeng county plants come from Fufangxiang, Taihe town and Taiyuan county; 2 Yanxi county strains come from Gao Fuzhen; 8 Lo an county strains come from Bianzhan town and Zengtian town; specifically shown in table 1.

TABLE 1 bacterial strain information of Ralstonia solanacearum isolated from Shaw province, Shazhou city

Selecting 4 bacterial wilt bacteria, continuously culturing for 65h on a growth curve tester, monitoring the growth dynamics of the bacterial wilt bacteria of tobacco, and drawing a growth curve of the bacterial wilt bacteria, as shown in figure 1.

As can be seen from FIG. 1, the ralstonia solanacearum grows rapidly within 4-19 h, is in logarithmic growth phase, the ralstonia solanacearum grows relatively stably within 19-38 h, and the ralstonia solanacearum begins to die gradually after 38 h. In the reagent sensitivity test, bacterial liquid cultured for about 19h is selected, the growth activity of the bacterial strain is higher, the OD600 value of the bacterial liquid represents the growth amount of ralstonia solanacearum, and the influence of the reagent treatment on the growth of the ralstonia solanacearum is analyzed by comparing the OD value.

Experimental example 1 determination of drug sensitivity of Ralstonia solanacearum to fluazinam and dianiline

1.1, measuring the drug sensitivity of the ralstonia solanacearum to fluazinam by adopting a growth curve measuring instrument.

And picking a single colony from a well-grown ralstonia solanacearum streak plate, adding the single colony into an NA liquid culture medium, and performing shake culture for 19 hours for later use. Adding fluazinam solutions with different concentrations into an NA liquid culture medium according to a volume ratio of 1:100 (volume ratio) to ensure that the concentrations of fluazinam in a final system are respectively 0, 0.14, 0.18, 0.25, 0.35 and 0.5 mu g/ml; wherein "0" is NA culture medium containing only dimethyl sulfoxide as Control (CK).

Adding 3 μ L of liquid medicine with different concentrations, 250 μ L of nutrient broth and 50 μ L of bacterial liquid of Ralstonia solanacearum into each well of the sample adding plate, and repeating for 3 times. The sample adding plate is placed into a growth curve tester, and the OD value is measured at the temperature of 28-30 ℃ every 30 min. The formula for calculating the growth inhibition rate of the medicament to ralstonia solanacearum is as follows: inhibition rate (OD)_{Blank control increase value}-OD_{Agent treatment increment})/OD_{Blank control increase value}X 100%. Taking logarithm of the concentration of the medicament as an x axis and a probability value of the inhibition rate as a y axis, calculating a toxicity regression curve equation y as ax + b and a correlation coefficient r thereof according to a linear relation between the logarithm of the concentration of the medicament and the probability value of the inhibition rate, and calculating the effective inhibition medium concentration EC of the medicament on pathogenic bacteria₅₀。

40 tobacco ralstonia solanacearum strains were obtained by co-isolation from 7 regions in Jiangxi province, and the results of drug sensitivity are shown in Table 2.

TABLE 2 susceptibility profile of ralstonia solanacearum to fluazinam

The results in Table 2 show that fluazinam has EC for all strains tested₅₀The maximum EC value is 0.1471-0.8904 mu g/mL₅₀Value and minimum EC₅₀The difference between the values was 6.05 times, the average EC₅₀The value was 0.3050. mu.g/mL, indicating that the difference in sensitivity of Ralstonia solanacearum to fluazinam was small. Wherein, EC₅₀The lowest and highest value strains were from loran, EC from other regional strains₅₀With values in between.

According to the distribution of the ralstonia solanacearum sensitivity, a sensitivity baseline of ralstonia solanacearum to 5 medicaments is established, as shown in fig. 2.

In FIG. 2, the frequency distribution of the sensitivity of the bacterial strain of ralstonia solanacearum to fluazinam is a continuous unimodal curve, which indicates that the test bacterial strain is sensitive to fluazinam and can be used for the control of bacterial wilt. The sensitive baselines are normally distributed and are continuous unimodal curves, and the drug-resistant sub-population does not appear, so that the method can be used for monitoring field resistant strains.

1.2 according to the above evaluation methods, the concentrations of the individual bisphenylalan were controlled to 0(CK), 0.02, 0.03, 0.04, 0.05 and 0.08. mu.g/ml, and the results of the drug sensitivity to 40 bacterial wilt pathogens of tobacco, which were co-isolated from 7 regions in Jiangxi province, are shown in Table 3.

TABLE 3 susceptibility profile of Ralstonia solanacearum to dichlofluanid

The results in Table 3 show that the sensitivity of ralstonia solanacearum to dianiline is high, and the average EC is₅₀A value of 0.0378. mu.g/mL, a relatively narrow sensitivity distribution range, and a minimum EC₅₀Value and maximum EC₅₀The values were 0.0187. mu.g/mL and 0.0534. mu.g/mL, respectively, differing by only 2.86 times from Richuan and Guangchang, respectively. As can be seen from the sensitivity baseline (FIG. 3), the sensitivity of ralstonia solanacearum to dianiline is distributed in a unimodal curve, which indicates that the test strains are sensitive to dianiline and no drug-resistant strains appear.

Experimental example 2 Joint virulence determination of a drug when fluazinam participates in compounding

On the basis of single-dose toxicity measurement, fluazinam is respectively mixed with 3 kinds of nano pesticides (nano sulfur, nano copper and nano silver), kasugamycin and benziothiazolinone according to the volume ratio of 80: 1. 40: 1. 20: 1. the inhibition ratio of the compound medicament on the ralstonia solanacearum is determined by 9 mixture ratios of 4:1, 1:4, 1:20, 1:40 and 1:80, and the final concentration of the compound medicament is shown in table 4.

TABLE 4 Final concentration of the combination

Medicament	Compounding ratio	Concentration (μ g/ml)
			Fluazinam and nano sulfur compound	80：1、40：1、20：1、4:1	0、0.12、0.16、0.2、0.4、0.8
Fluazinam and nano sulfur compound	1:1、1:4、1:20、1:40、1:80	0、0.5、2、4、8、16、40
			Fluazinam and nano-copper compounding	80：1、40：1、20：1、4:1、1:1	0、0.14、0.18、0.25、0.35、0.5
Fluazinam and nano-copper compounding	1:4、1:20、1:40、1:80	0、0.2、0.5、1、5、10
			Fluazinam and nano silver compounding	80：1、40：1、20：1、4:1、1:1	0、0.14、0.18、0.25、0.35、0.5
Fluazinam and nano silver compounding	1:4、1:20、1:40、1:80	0、0.2、0.5、1、5、10
			Fluazinam and kasugamycin compound	80：1、40：1、20：1、4:1、1:1	0，0.14，0.18，0.25，0.35，0.5
Fluazinam and kasugamycin compound	1:4、1:20、1:40、1:80	0，0.2，0.5，1，5，10
			Fluazinam and benziothiazolinone compound	80：1、40：1、20：1、4:1、1:1	0，0.14，0.18，0.25，0.35，0.5
Fluazinam and benziothiazolinone compound	1:4、1:20、1:40、1:80	0，0.1，0.2，0.3，0.5，1，5

In table 4, when the fluazinam and the nano sulfur are compounded according to the compounding ratio of 80:1, six levels of 0, 0.12, 0.16, 0.2, 0.4 and 0.8 are respectively tested, and a fluazinam solution with the concentration of 0.12 mug/ml and a nano sulfur solution with the concentration of 0.12 mug/ml are compounded according to the volume ratio of 80:1 by taking the concentration of 0.12 mug/ml as an example. The fluazinam solution is prepared from fluazinam mother liquor (10)⁵Mu g/mL) and dimethyl sulfoxide. The nano sulfur solution is prepared from a commercial concentration nano sulfur solution (10)³μ g/mL) and sterilized waterAnd (4) preparing the composition. The kasugamycin solution is prepared from kasugamycin mother liquor (10)⁴Mu g/mL) and sterilized water. The benziothiazolinone solution is prepared from benziothiazolinone mother liquor (10)⁵Mu g/mL) and dimethyl sulfoxide.

The combined action evaluation is carried out on the compound preparation by adopting a Wadley method, and the evaluation formula is as follows:

the theory of the mixture effectively inhibits the medium concentration EC₅₀(th)＝(a+b)/[a/EC(A)₅₀+b/EC(B)₅₀]

In the formula: a. b is the compounding proportion of fluazinam and nano pesticide (or kasugamycin and benziothiazolinone) respectively,%; EC (A)₅₀Is the effective inhibiting middle concentration of fluazinam, mu g/mL; EC (B)₅₀The concentration is the effective inhibition medium concentration of the nano pesticide, namely mu g/mL.

Coefficient of synergy SR ═ EC₅₀(th)/EC₅₀(ob)

In the formula: EC (EC)₅₀(th) is the theoretical effective inhibition median concentration of the mixture, μ g/mL; EC (EC)₅₀(ob) is the observed effective inhibitory median concentration of the combination, μ g/mL.

SR is less than or equal to 0.5, which shows that the combination of the two medicaments has antagonistic action; when SR is 0.5-1.5, the two agents are compounded to have an additive effect; SR is more than or equal to 1.5, which shows that the combination of the two medicaments has synergistic effect.

2.1 Combined toxicity of fluazinam and nano sulfur on Ralstonia solanacearum

Respectively measuring the toxicity of fluazinam (0, 0.14, 0.18, 0.25, 0.35 and 0.5 mu g/ml), nano sulfur solution single agent (0, 2, 4, 40, 60 and 80 mu g/ml) and fluazinam and nano sulfur in different proportions on ralstonia solanacearum, and the results are shown in table 5.

TABLE 5 Joint toxicity of fluazinam and Sulfur nanoparticles on Ralstonia solanacearum

As can be seen from Table 5, 9 compounding ratios of fluazinam and nano sulfur have an inhibiting effect on Ralstonia solanacearum, and EC₅₀Value distribution 0.2812-6.0406 mu g/mL, greater than EC of fluazinam single agent₅₀EC value of 0.2073 mug/mL, but less than nano sulfur single dose₅₀The value was 17.3998. mu.g/mL. EC with increasing nano-sulfur ratio₅₀The value increases and the sensitivity of the agent decreases.

According to the inhibition rate of the single agent and the compound agent on the ralstonia solanacearum, the joint toxicity effect of the fluazinam and the nano sulfur compound is evaluated by a Wadley method. As can be seen from Table 5, most of the formulation ratios have additive effects; when the fluazinam and the nano sulfur are compounded according to the volume ratio of 1:1, the fluazinam and the nano sulfur have antagonistic action, the synergistic coefficient is 0.2706, and the compounding ratio is avoided when the fluazinam and the nano sulfur are applied; when the fluazinam and the nano sulfur are compounded according to the volume ratio of 1:40, the synergistic coefficient is maximum and is 1.5955, which shows that the compounded fluazinam and the nano sulfur have synergistic effect under the volume ratio.

2.2 Combined toxicity of fluazinam and nano-copper on Ralstonia solanacearum

Respectively measuring the toxicity of fluazinam (0, 0.14, 0.18, 0.25, 0.35 and 0.5 mu g/ml), nano-copper solution single agent (0, 1, 2.5, 5, 10 and 30 mu g/ml) and fluazinam and nano-copper compounded according to different proportions on ralstonia solanacearum, and the results are shown in table 6.

TABLE 6 Joint toxicity of fluazinam and nano-copper compounding on Ralstonia solanacearum

As can be seen from Table 6, fluazinam and nano-copper are compounded according to 9 proportions, and different bactericide compositions have EC for ralstonia solanacearum₅₀The value distribution range is 0.1422-7.2033 mu g/mL, and the values are all less than the EC of the nano-copper single agent on ralstonia solanacearum₅₀The value was 21.4797. mu.g/mL. When the fluazinam and the nano-copper are compounded according to the volume ratio of 1:1 to 1:4, the synergistic coefficient of the compound is less than 0.5, which shows that the compounding of the fluazinam and the nano-copper shows antagonism under the proportion; and the other 7 compounding proportions have the synergistic coefficient of the fluazinam and the nano copper of 0.7214-1.1867, which shows that the fluazinam and the nano copper have additive effect.

2.3 Combined toxicity of fluazinam and nano-silver on ralstonia solanacearum

Respectively measuring the toxicity of fluazinam (0, 0.14, 0.18, 0.25, 0.35 and 0.5 mu g/ml), nano-silver solution single agent (0, 1, 2.5, 5, 10 and 30 mu g/ml) and fluazinam and nano-silver compounded according to different proportions on ralstonia solanacearum, and the results are shown in table 7.

TABLE 7 Joint toxicity of fluazinam and nano-silver compounding on Ralstonia solanacearum

As can be seen from Table 7, fluazinam and nano-silver have inhibition effects on ralstonia solanacearum under different compounding ratios, and the mixture of 9 compounding bactericides has EC on ralstonia solanacearum₅₀The value distribution range is 0.3873-9.4596 mu g/mL, and the values are all less than the EC of the nano-silver single agent on ralstonia solanacearum₅₀The value of 15.4204 mu g/mL is larger than the EC of fluazinam single dose on ralstonia solanacearum₅₀The value is obtained.

Evaluating the joint toxicity of the fluazinam and the nano-silver by a Wadley method, wherein the fluazinam and the nano-silver show antagonism when the fluazinam and the nano-silver are compounded according to the ratio of 20:1, 4:1, 1:1 and 1: 4; when the fluazinam and the nano silver are compounded according to the ratio of 80:1, 40:1, 1:20, 1:40 and 1:80, the fluazinam and the nano silver have additive effects, and when the fluazinam and the nano silver are compounded according to the ratio of 1:20, the coefficient of synergy is 1.4067.

Experimental example 3 measurement of combined toxicity of agents when dimoxystrobin participates in compounding

The combined toxicity of the compound medicament is determined when the dianiline participates in the compound in the manner of the experimental example 2. On the basis of single-dose toxicity measurement, the method comprises the following steps of respectively mixing the dianiline with 3 kinds of nano pesticides (nano sulfur, nano copper and nano silver), kasugamycin and benziothiazolinone according to the volume ratio of 80: 1. 40: 1. 20: 1. the inhibition ratio of the compound medicament on the ralstonia solanacearum is determined by 9 mixture ratios of 4:1, 1:4, 1:20, 1:40 and 1:80, and the final concentration of the compound medicament is shown in a table 8.

TABLE 8 Final concentrations of the different combinations

Medicament	Compounding ratio	Concentration (μ g/ml)
			Bifenarimol and nano sulfur compound	80：1、40：1、20：1、4:1、1:1	CK，0.02，0.03，0.04，0.05，0.1
Bifenarimol and nano sulfur compound	1:4、1:20、1:40、1:80	CK，0.04，0.1，1，5，10
			Bifenarimol and nano-copper compounding	80：1、40：1、20：1、4:1、1:1	CK，0.02，0.03，0.04，0.05，0.1
Bifenarimol and nano-copper compounding	1:4、1:20、1:40、1:80	CK，0.04，0.1，1，5，10
			Bifenariman and nano silver compounding	80：1、40：1、20：1、4:1、1:1	CK，0.02，0.03，0.04，0.05，0.1
Bifenariman and nano silver compounding	1:4、1:20、1:40、1:80	CK，0.04，0.1，1，5，10
			Bifenarimol and kasugamycin compound	80：1、40：1、20：1、4:1、1:1	CK，0.02，0.03，0.04，0.05，0.1
Bifenarimol and kasugamycin compound	1:4、1:20、1:40、1:80	CK，0.04，0.1，1，5，10
			Bifenarimol and benziothiazolinone compound	80：1、40：1、20：1、4:1、1:1	CK，0.008，0.02，0.03，0.04，0.05，0.1
Bifenarimol and benziothiazolinone compound	1:4、1:20、1:40、1:80	CK，0.02，0.04，0.1，0.5，0.8，4

3.1 Combined toxicity of Bifenarimol and Nano Sulfur on Ralstonia solanacearum

The toxicity of the bactericidal composition on the tobacco ralstonia solanacearum, which is prepared by compounding the diphenyamine (CK, 0.02, 0.03, 0.04, 0.05, 0.08 mu g/ml), the single nano-sulfur solution (CK, 1, 2.5, 5, 10, 30 mu g/ml) and the nano-sulfur in different proportions, is respectively measured, and the results are shown in Table 9.

TABLE 9 Joint toxicity of Bifenarimol and Sulfur nanoparticles on Ralstonia solanacearum

As can be seen from Table 9, 9 compounding ratios of dimoxystrobin and nano-sulfur have an inhibiting effect on ralstonia solanacearum, and EC₅₀The value distribution is 0.0391-0.7695 mu g/mL, and is greater than the EC of the single agent of the dianisidine₅₀EC value of 0.0387 mug/mL, but less than nano sulfur single dose₅₀The value was 12.0727. mu.g/mL. EC with increasing nano-sulfur ratio₅₀The value increases and the sensitivity of the agent decreases.

According to the inhibition rate of the single agent and the compound agent on the ralstonia solanacearum, the joint toxicity effect of the compound of the dianiline and the nano sulfur is evaluated by a Wadley method. As can be seen from Table 9, most of the formulation ratios have additive effects; when the dianisidine and the nano sulfur are compounded according to the volume ratios of 1:20, 1:40 and 1:80, the synergistic coefficient reaches 3.24-6.14, and the synergistic effect is realized by compounding the dianisidine and the nano sulfur according to the three volume ratios.

3.2 Combined toxicity of Bifenarimol and Nano copper on Ralstonia solanacearum

The toxicity of the bactericide composition prepared by compounding the dianiline (CK, 0.02, 0.03, 0.04, 0.05, 0.08 mu g/ml), the single nano-copper solution (CK, 1, 2.5, 5, 10, 30 mu g/ml) and the nano-copper in different proportions on the ralstonia solanacearum is respectively measured, and the results are shown in Table 10.

TABLE 10 Joint toxicity of Bifenarimol and nanocopper combinations against Ralstonia solanacearum

As can be seen from Table 10, when the dianiline and the nano-copper are compounded according to 9 proportions, EC of different bactericide compositions on ralstonia solanacearum₅₀The value distribution range is 0.0165-1.0978 mu g/mL, and the EC compounded by the dimoxystrobin and the nano-copper according to the volume ratio of 80:1₅₀The value is slightly less than EC of single agent of dimoxystrobin₅₀The value is obtained. When the dianiline and the nano-copper are compounded according to the volume ratio of 1:4 to 1:20, the synergistic coefficient of the compound is less than 0.5, which shows that the compounding of the dianiline and the nano-copper shows antagonism under the proportion; and the other 7 compounding proportions have the synergistic coefficient of the dianiline and the nano-copper of 0.59-0.95, which shows that the two have additive action.

3.3 Combined toxicity of Bifenarimol and Nano silver to Ralstonia solanacearum

The toxicity of the bactericide composition prepared by compounding the dianiline (CK, 0.02, 0.03, 0.04, 0.05, 0.08 mu g/ml), the nano-silver solution single agent (CK, 1, 2.5, 5, 10, 30 mu g/ml) and the dianiline and the nano-silver according to different proportions on the ralstonia solanacearum is respectively measured, and the results are shown in Table 11.

TABLE 11 Joint toxicity of Bifenarimamine and Nano silver compounding on Ralstonia solanacearum

As can be seen from Table 11, the dianiline and the nano-silver have inhibition effects on ralstonia solanacearum under different compounding ratios, and the mixture of the 9 compounding bactericides has EC on ralstonia solanacearum₅₀The value distribution range is 0.0269-1.9219 mug/mL, and the values are all less than EC of nano silver single dose on ralstonia solanacearum₅₀The value of 15.7669 mu g/mL is larger than the EC of the single-dose dianiline on pseudomonas solanacearum₅₀The value is obtained.

Evaluating the joint toxicity of the dianiline and the nano-silver by a Wadley method, wherein the dianiline and the nano-silver show antagonism when the dianiline and the nano-silver are compounded according to the ratio of 1:1, 1:4 and 1: 40; the other different proportions of the components have additive effect, and when the dianiline and the nano-silver are compounded in a ratio of 1:80, the highest synergistic coefficient is 1.06.

3.4 Combined toxicity of Bifenarimol and kasugamycin on tobacco ralstonia solanacearum

The toxicity of the bactericide composition prepared by compounding the dianiline single agent (CK, 0.02, 0.03, 0.04, 0.05, 0.08 mu g/ml), the kasugamycin single agent (CK, 1, 2.5, 5, 10, 30 mu g/ml) and the dianiline and the kasugamycin in different proportions on the tobacco ralstonia solanacearum is respectively measured, and the results are shown in Table 12.

TABLE 12 Combined virulence of Bifenarimol and kasugamycin on tobacco ralstonia solanacearum

As can be seen from Table 12, the dichloramine and kasugamycin all have the inhibiting effect on ralstonia solanacearum under different compounding ratios, and the mixture of the 9 compounding bactericides has the EC on ralstonia solanacearum₅₀The value distribution range is 0.0393-2.9944 mu g/mL, the diphenicyclamine and kasugamycin have antagonistic action when compounded according to the proportion of 1:4 and 1:40, the rest compounding proportions are additive, and the highest synergistic coefficient is 1.06 when the diphenicyclamine and the kasugamycin are compounded according to the proportion of 80: 1.

3.5 Combined toxicity of Bifenarimol and Thiomycins on Ralstonia solanacearum

The toxicity of the fungicide composition prepared by compounding the dianiline single agent (CK, 0.02, 0.03, 0.04, 0.05, 0.08 mu g/ml), the benziothiazolinone single agent (0, 0.3, 0.5, 0.8, 4, 8 mu g/ml) and the benziothiazolinone at different ratios on the ralstonia solanacearum is respectively measured, and the results are shown in Table 13.

TABLE 13 Joint virulence of Diphenylamine and Thiomycinone combinations against Ralstonia solanacearum

As can be seen from Table 13, the bisphenylamine and the benziothiazolinone have the inhibiting effect on ralstonia solanacearum under different compounding ratios, and the mixture of the 9 compounding bactericides has the EC on ralstonia solanacearum₅₀The value distribution range is 0.0243-0.6109 mug/mL, when the dimoxystrobin and the benziothiazolinone are compounded according to the proportion of 1:4, antagonism is achieved, the rest compounding proportion has additive effect, and when the dimoxystrobin and the benziothiazolinone are compounded according to the proportion of 4:1, the maximum synergistic coefficient is 0.87.

In the experimental example, the compounding of the dianisidine with five agents mostly has additive effect, and the compounding with the nano sulfur in a specific ratio also has synergistic effect (table 14).

TABLE 14 optimal compounding ratio of dimoxystrobin and 5 drugs

According to the above experimental examples, the following are summarized:

the ralstonia solanacearum has higher genetic variation and propagation capacity, is often mixed with other fungi and oomycete diseases, is very easy to cause disease outbreak and epidemic under the appropriate environmental conditions, and brings destructive disasters to tobacco production. The chemical control has important function in the control of tobacco bacterial wilt, the current medicament for controlling bacteria mainly takes agricultural antibiotics and copper preparations as main materials, compared with the medicament for controlling fungi, the chemical medicament with deficient bacteria-killing medicament variety, unique deep excavation action mechanism and excellent control effect is particularly important for the control and resistance control of the tobacco and other crop bacterial wilt.

The compound pesticide of the invention provides more alternative pesticides for preventing and treating tobacco bacterial wilt, can expand the control spectrum of the pesticides, delay the generation of drug resistance and provide theoretical basis for the reduction and high-efficiency use of pesticides.

Claims

1. A nano sulfur compound medicament is characterized in that the effective components consist of nano sulfur and one of dimoxystrobin and fluazinam; the mass ratio of the dimoxystrobin to the nano sulfur is 1: (20-80); the mass ratio of the fluazinam to the nano sulfur is 1: 40.

2. The nano sulfur compound agent according to claim 1, wherein the nano sulfur has a particle size of 7 nm.

3. The nano sulfur compound medicament as claimed in claim 1 or 2, wherein the formulation is water dispersible granule, wettable powder, suspension, emulsifiable concentrate, aqueous emulsion or microemulsion.

4. The application of the nano sulfur compound medicament as claimed in claim 1 in the aspect of preventing and treating bacterial wilt of plants.

5. The use of claim 4, wherein the bacterial wilt disease in a plant is tobacco bacterial wilt disease.