Application of phloroglucinol compound in inhibition of fusarium plant pathogenic fungi and prevention and treatment of related plant diseases

Abstract

The invention discloses application of phloroglucinol compounds to inhibition of fusarium plant pathogenic fungi and prevention and treatment of related plant diseases, and belongs to the technical field of agricultural bactericides. In order to solve the technical problems that an existing method for preventing and treating plant diseases caused by fusarium is poor in effect and has defects, 15 compounds are extracted from dryopteris fragrans, and structural identification shows that the 15 compounds belong to phloroglucinol compounds. Then, the in-vitro bacteriostatic effects of the 15 compounds on fusarium oxysporum, fusarium graminearum and fusarium laminatum are detected, the compounds 5, 6, 7, 8, 10, 11, 13 and 14 are found to have bacteriostatic effects on fusarium fungi, and the compound 10 (aspidinol B) has the strongest in-vitro inhibitory effect on the three fusarium fungi; furthermore, an in-vivo antibacterial experiment proves that the compound 10 has a good prevention and treatment effect on pathogenic fungal diseases of three fusarium plants.

Description

Technical Field

[0001] The invention belongs to the technical field of agricultural fungicides, and specifically relates to the application of phloroglucinol compounds in inhibiting plant pathogenic fungi of the genus Fusarium and preventing and controlling related plant diseases. Background Art

[0002] Fusarium sp. is a common plant pathogenic fungus that can infect a variety of common crops such as potatoes and wheat, causing potato dry rot, wheat crown rot, etc., which greatly reduces crop yields. Traditional agriculture uses methods such as crop rotation and burning of stubble to prevent and control Fusarium diseases, but these methods are sometimes ineffective or ineffective. In modern agriculture, chemical antimicrobial agents are often used to prevent and control Fusarium diseases. However, the long-term and unreasonable application of antimicrobial agents has brought drug resistance to plant pathogenic fungi and caused environmental pollution. More importantly, some common antimicrobial agents such as carbendazim are toxic to humans and animals. Eating crops with too much drug residue can cause vomiting, abdominal pain, diarrhea and other symptoms. Even if the residue is very small, long-term consumption of crops that have been applied with these drugs will cause the drugs to accumulate in the body, posing a potential threat to human health. Therefore, it is urgent to develop some new natural, low-toxic antibacterial compounds for the prevention and control of Fusarium plant diseases.

[0003] Dryopteris fragrans (L.) Schott is a plant of the Dryopteris family and Dryopteris genus. It grows under forests at an altitude of 700-2400 meters. According to folk prescriptions in northern China, Dryopteris fragrans can treat a variety of skin diseases such as psoriasis, rash, dermatitis and acne, and has extremely obvious therapeutic effects on senile skin itching, adolescent acne and flat warts; in addition, Dryopteris fragrans also has obvious therapeutic effects on rheumatoid arthritis. In recent years, the results of many pharmacological studies have shown that Dryopteris fragrans has multiple effects such as anti-inflammatory, analgesic, antifungal, anti-tumor, antioxidant, and psoriasis treatment. It is a rare wild medicinal plant resource with development potential and application prospects. At present, the active ingredients reported in Dryopteris fragrans include phloroglucinols, flavonoids, terpenes, phenylpropanoids and volatile oil compounds, among which phloroglucinol compounds are the majority, mainly including phloroglucinol, phloroglucinol PB, phloroglucinol and phloroglucinol BB. However, the existing reports on phloroglucinol active ingredients are mostly that they can inhibit fungi or bacteria that cause human infection, and there are few reports on their use in inhibiting plant pathogenic fungi, especially plant pathogenic fungi of the genus Fusarium. Therefore, it would be of great significance if compounds that can be used to prevent and treat plant diseases caused by plant pathogenic fungi of the genus Fusarium could be screened from phloroglucinol compounds. Summary of the invention

[0004] In order to solve the technical problems that the existing plant disease prevention and control methods caused by Fusarium plant pathogenic fungi are not effective and have defects, the present invention extracts 15 compounds from Dryopteris odorifera, and the structural identification shows that the 15 compounds all belong to phloroglucinol compounds. Then the present invention detects the in vitro antibacterial effects of the 15 phloroglucinol compounds on three kinds of Fusarium fungi (Fusarium oxysporum, Fusarium graminearum and Fusarium spp.), and finds that compound 5, compound 6, compound 7, compound 8, compound 10 (smilanophenol B), compound 11, compound 13 and compound 14 have antibacterial effects on Fusarium fungi, among which smilanophenol B has the strongest in vitro inhibitory effect on the three kinds of Fusarium fungi; and then the in vivo antibacterial experiment confirms that smilanophenol B has good control effects on the three kinds of Fusarium plant pathogenic fungal diseases.

[0005] In order to solve the above technical problems and achieve the corresponding technical effects, the present invention provides the following technical solutions: The first object of the present invention is to provide the use of phloroglucinol compounds in inhibiting the growth of mycelium of plant pathogenic fungi of the genus Fusarium, wherein the phloroglucinol compound is compound 5, compound 6, compound 7, compound 8, compound 10, compound 11, compound 13 or compound 14, having the following molecular structure:

[0006]

[0007] In one embodiment of the present invention, the phloroglucinol compound is obtained by extraction from plants or by chemical synthesis or biosynthesis.

[0008] In one embodiment of the present invention, the plant pathogenic fungus of the genus Fusarium is Fusarium oxysporum, Fusarium graminearum or Fusarium proliferatum.

[0009] Preferably, the phloroglucinol compound is compound 10.

[0010] The second object of the present invention is to provide the use of the above-mentioned phloroglucinol compounds in preventing and controlling plant diseases caused by plant pathogenic fungi of the genus Fusarium.

[0011] In one embodiment of the present invention, the plant pathogenic fungus of the genus Fusarium is Fusarium oxysporum, Fusarium graminearum or Fusarium solani.

[0012] Preferably, the phloroglucinol compound is compound 10.

[0013] The third object of the present invention is to provide a fungicide containing the above-mentioned phloroglucinol compound for use in inhibiting plant pathogenic fungi of the genus Fusarium.

[0014] The fourth object of the present invention is to provide a pesticide containing the above-mentioned phloroglucinol compound for use in preventing and controlling plant diseases caused by plant pathogenic fungi of the genus Fusarium.

[0015] In one embodiment of the present invention, the plant pathogenic fungus of the genus Fusarium is Fusarium oxysporum, Fusarium graminearum or Fusarium solani.

[0016] Preferably, the phloroglucinol compound is compound 10.

[0017] The fifth object of the present invention is to provide the use of the above-mentioned phloroglucinol compounds in the preparation of a fungicide for inhibiting plant pathogenic fungi of the genus Fusarium.

[0018] The sixth object of the present invention is to provide the use of the above-mentioned phloroglucinol compounds in the preparation of pesticides for preventing and controlling plant diseases caused by plant pathogenic fungi of the genus Fusarium.

[0019] In one embodiment of the present invention, the plant pathogenic fungus of the genus Fusarium is Fusarium oxysporum, Fusarium graminearum or Fusarium solani.

[0020] Preferably, the phloroglucinol compound is compound 10.

[0021] Beneficial effects of the present invention:

[0022] The present invention extracts 15 compounds from Dryopteris odorifera, and through structural identification, it is found that the 15 compounds all belong to phloroglucinol compounds. Then the present invention detects the in vitro antibacterial effects of the 15 phloroglucinol compounds on three kinds of Fusarium fungi (Fusarium oxysporum, Fusarium graminearum and Fusarium graminearum), and finds that compound 5, compound 6, compound 7, compound 8, compound 10, compound 11, compound 13 and compound 14 have antibacterial effects on Fusarium fungi, among which compound 10 has the strongest in vitro inhibitory effect on the three kinds of Fusarium fungi; and then through in vivo antibacterial experiments, it is confirmed that compound 10 has good prevention and control effects on the three kinds of Fusarium plant pathogenic fungal diseases.

[0023] The 15 phloroglucinol compounds provided by the present invention have clear structures, can be obtained by extraction from Dryopteris odoratissimus, and can also be synthesized by chemical means, laying a foundation for research on the inhibition of plant pathogenic fungi by Dryopteris odoratissimus, clarifying the antibacterial active ingredients of Dryopteris odoratissimus, further promoting the effective application of Dryopteris odoratissimus, and also providing new options and approaches for the development of new natural pesticides, which can effectively fill the deficiency of antibacterial natural compounds and have good application prospects in the preparation of antifungal pesticides. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The chemical structural formula diagram of phloroglucinol compounds 1-15;

[0025] Figure 2 The graph is a graph showing the in vitro inhibitory effects of different concentrations of phloroglucinol compounds 1-15, carbendazim and chlorpyrifos on Fusarium oxysporum hyphae;

[0026] Figure 3 The graph shows the in vitro inhibitory effects of different concentrations of phloroglucinol compounds 1-15, carbendazim and carbendazim on Fusarium graminearum hyphae;

[0027] Figure 4 The in vitro inhibitory effects of different concentrations of phloroglucinol compounds 1-15, carbendazim and chlorpyrifos on the hyphae of Fusarium pyralidum;

[0028] Figure 5 The graph shows the in vivo control effect of compound 10, carbendazim and carbendazim on potato Fusarium disease at different concentrations. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific implementation methods and the accompanying drawings of the specification. The embodiments described in the present invention are not all embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0030] The experimental methods used in the following examples are all conventional methods unless otherwise specified, and the materials, reagents and instruments used are all conventional materials, reagents and instruments in the art unless otherwise specified, and can be obtained by those skilled in the art through commercial channels.

[0031] The test fungi used in the present invention: Fusarium oxysporum, Fusarium graminearum and Fusarium proliferatum are provided by Heilongjiang Academy of Agricultural Sciences.

[0032] The chemical structural formulas of 15 phloroglucinol compounds (compounds 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 and 15) involved in the present invention are as follows: Figure 1 As shown, these 15 phloroglucinol compounds can be directly purchased through commercial channels, or extracted from Dryopteris odorifera by the following extraction method:

[0033] S1. Obtaining glandular hair extract: prepare 10 kg of dried Dryopteris odorata, pick up a cotton ball soaked in acetone with tweezers and wipe the entire leaf of Dryopteris odorata, covering as large an area as possible, until the glandular hairs are removed. During this process, the acetone and cotton wool are changed several times to filter the acetone, thereby dissolving the metabolites of the glandular trichomes; the filtered acetone solution is placed in a rotary evaporator and rotary evaporated in a reduced pressure 42°C water bath to obtain 14 g of glandular hair extract.

[0034] S2. Separation of glandular hair extract: The glandular hair extract was separated on a silica gel column using petroleum ether / CHCl 3 (70:30 to 0:100), CHCl 3 / acetone and acetone / methanol (90:10 to 0:100) to obtain three fractions: Fr.A (5.53 g), Fr.B (5.93 g) and Fr.C (2.54 g); then Fr.A was selected for medium pressure liquid chromatography using a C18-CE column and chromatographed with AcN / H 2 O (10:90 to 100:0) to obtain 7 components (Fr.A.1-Fr.A.7).

[0035] S3. Isolation of compound 7: Compound 7 (10 mg) was prepared from Fr.A.2 (51 mg) on ​​a silica gel column using petroleum ether / CHCl 3 / FA (90:10:1 to 0:100:1) was used for elution.

[0036] Separation of S4, compound 6, compound 8, compound 9, compound 10 and compound 11: Fr.A.3 (310 mg) was eluted on a silica gel column with petroleum ether / ethyl acetate (90:10 to 0:100) to obtain 6 fractions (Fr.A.3.1-Fr.A.3.6); compound 9 (3 mg) was obtained by eluting Fr.A.3.1 (12 mg) on ​​a silica gel column with petroleum ether / chloroform (90:10 to 0:100) as the eluent; semi-preparative high performance liquid chromatography (MeCN / H 2 O / FA, 42:58:1, 3 mL / min) to separate Fr.A.3.3 (14 mg) to obtain compound 6 (2 mg, tR = 15.2 min) and compound 8 (2 mg, tR = 25.3 min); Fr.A.3.4 (15 mg) was separated by semi-preparative HPLC (MeCN / H 2 O / FA, 10:90:1 to 100:0:1, 3 mL / min) to give compound 11 (2 mg, tR=24.3 min) and compound 10 (2 mg, tR=39.4 min).

[0037] Separation of S5, compound 4 and compound 5: Fr.A.5 (531 mg) was eluted on a silica gel column with petroleum ether / ethyl acetate (90:10 to 0:100) to obtain 5 fractions (Fr.A.5.1-Fr.A.5.5); Fr.A.5.1 (138 mg) was separated by eluting with petroleum ether / acetone / isopropanol (100:0.1:0.01 to 100:1:0.1) on a silica gel column and purified by semi-preparative high performance liquid chromatography (MeCN / H 2 O / FA, 60:40:1, 3 mL / min) to obtain compound 5 (2 mg, tR=31.7 min); Fr.A.5.4 (40 mg) was separated by elution with petroleum ether / acetone / isopropanol (100:0.1:0.01 to 100:1:0.1) on a silica gel column to obtain compound 4 (2 mg).

[0038] S6. Isolation of compound 1: Semi-preparative HPLC (MeCN / H 2 O / FA, 60:40:1, 3 mL / min) was used to separate Fr.A.6 (36 mg) to obtain compound 1 (2 mg, tR = 19.1 min).

[0039] Separation of S7, Compound 2, Compound 3, Compound 12, Compound 13, Compound 14 and Compound 15: Fr.A.7 (1.8 g) was separated by a silica gel column with petroleum ether / acetone / isopropanol (100:0.1:0.01 to 100:1:0.1) and eluted to obtain five fractions (Fr.A.7.1-Fr.A.7.5); Fr.A.7.3 (670 mg) was purified by semi-preparative high performance liquid chromatography (MeCN / H 2 O / FA, 70:30:1, 3 mL / min) was used to separate and obtain compound 12 (2 mg, tR=20.0 min), compound 2 (2 mg, tR=21.1 min), compound 3 (2 mg, tR=23.2 min), compound 13 (8 mg, tR=25.9 min), compound 14 (10 mg, tR=29.3 min) and compound 15 (8 mg, tR=31.0 min).

[0040] The present invention separates 15 compounds according to the above extraction process, and the purity reaches more than 95%. The structures of the 15 compounds obtained are identified by nuclear magnetic resonance. It is confirmed that the 15 compounds are all phloroglucinol compounds, with the structural formula as shown below: Figure 1 As shown, compounds 1-6 are new compounds.

[0041] Example 1: In vitro inhibitory effects of phloroglucinol compounds 1-15 on three plant pathogenic fungi of the genus Fusarium

[0042] This example detects the in vitro antibacterial effects of phloroglucinol compounds 1-15 on three plant pathogenic fungi of the genus Fusarium (Fusarium oxysporum, Fusarium graminearum and Fusarium solani), and the specific method is as follows:

[0043] The sterilized PDA medium was cooled to 50-55°C, and different amounts of prepared stock solutions of different compounds were added to achieve different concentrations of the compounds in the PDA medium (0, 1.25, 2.5, 5.0, 10.0, 20.0 mg / L); at the same time, an equal volume of DMSO was added as a control, and benomyl and carbendazim were selected as positive controls. The fungal cake (about 5 mm in diameter) was placed in the center of the PDA medium and cultured in the dark at 28°C. Each experimental group consisted of 2 replicates. Mycelial growth was monitored every day, and the colony diameter was measured using a ruler (cross method). The antifungal effect was measured based on the radial growth of the mycelium. The inhibition rate was calculated using the following formula:

[0044] Mycelium growth inhibition rate (%) = (DD 1 ) / (DD 0 )×100%

[0045] Where D is the diameter of the negative control colony, D 1 is the diameter of the colonies in the culture medium treated with the experimental compound, D 0 is the diameter of the inoculated bacterial cake.

[0046] 1. In vitro inhibitory effects of phloroglucinol compounds 1-15 on Fusarium oxysporum

[0047] The present invention uses the above method to detect the in vitro inhibitory effect of phloroglucinol compounds 1-15 on Fusarium oxysporum. The results are as follows: Figure 2 As shown in Table 1, by observing the colony morphology of Fusarium oxysporum and measuring the colony diameter, it was found that compounds 8, 10, 11, and 13 had a strong inhibitory effect on Fusarium oxysporum. When the concentration reached 20 mg / L, the average inhibition rate (AIR) was ≥40%. The AIR of compounds 8, 11, and 13 were 40%, 40.48%, and 40.41%, respectively, which were stronger than the positive control hymexazol (AIR = 34.69%). Compound 10 had the best inhibitory effect on Fusarium oxysporum, with an AIR of 93.75%, much higher than other compounds and slightly lower than the positive control carbendazim (AIR = 103.64%).

[0048] Table 1 Average inhibition rate of different concentrations of compounds 1-15 on Fusarium oxysporum hyphae in vitro (AIR±SD)

[0049]

[0050] 2. In vitro inhibitory effects of phloroglucinol compounds 1-15 on Fusarium graminearum

[0051] The present invention uses the above method to detect the in vitro inhibitory effect of phloroglucinol compounds 1-15 on Fusarium graminearum. The results are as follows: Figure 3 As shown in Table 2, by observing the colony morphology of Fusarium graminearum and measuring the colony diameter, it was found that compounds 5, 6, 10, 13 and 14) had a strong inhibitory effect on Fusarium graminearum. When the concentration reached 20 mg / L, the average inhibition rate (AIR) was ≥40%, which were 41.67%, 58%, 91.49%, 40.01% and 46.94%, respectively. Among them, compound 10 had the best inhibitory effect on Fusarium graminearum, and its AIR was higher than the positive control oxamexazole (AIR=73.81%) and slightly lower than the positive control carbendazim (AIR=100%).

[0052] Table 2 Average inhibition rate of different concentrations of compounds 1-15 on Fusarium graminearum hyphae in vitro (AIR±SD)

[0053]

[0054] 3. In vitro inhibitory effects of phloroglucinol compounds 1-15 on F. proliferatum

[0055] The present invention uses the above method to detect the in vitro inhibitory effect of phloroglucinol compounds 1-15 on Fusarium erythrorhizium. The results are as follows: Figure 4 As shown in Table 3, by observing the colony morphology of Fusarium spp. and measuring the colony diameter, it was found that compounds 7, 8, and 10 had a strong inhibitory effect on Fusarium spp., and when the concentration reached 20 mg / L, the average inhibition rate (AIR) was >50%, which were 57.38%, 52.38%, and 77.5%, respectively. Among them, the antibacterial effects of compounds 7 and 10 were stronger than the positive control oxadiazine (AIR=55.26%), and lower than the positive control carbendazim (100%). Among the 15 compounds, compound 10 had the best inhibitory effect on Fusarium spp.

[0056] Table 3 Average inhibition rate of different concentrations of compounds 1-15 on Fusarium mycelium in vitro (AIR±SD)

[0057]

[0058]

[0059] 4. EC of phloroglucinol compounds 1-15 on mycelium of three strains of Fusarium 50 Value detection

[0060] The present invention uses GraphPad Prism 10 software to determine the half maximum effective concentration (EC) of compounds 1-15 on the mycelium of the above three Fusarium strains based on the relationship between inhibition and concentration. 50 ).

[0061] The results are shown in Table 4. Compounds 8, 10 and 11 showed good inhibitory activity against Fusarium oxysporum (EC 50 The results showed that the concentrations of hydroxyzine in the positive control group were 30.46 mg / L, 4.822 mg / L and 34.37 mg / L, respectively, which were better than the positive control group (EC 50 =34.88 mg / L), but inferior to another positive control carbendazim (EC 50 =3.619 mg / L); Compound 10 showed good inhibitory activity against Fusarium graminearum (EC 50 =6.051mg / L), which is better than the positive control, hydroxyzine (EC 50 =8.221 mg / L); Compounds 7 and 10 showed good inhibitory activity against Fusarium solani (EC 50 The results showed that the positive control of carbendazim (EC 50 =17.91 mg / L). Meanwhile, the inhibitory activity of compound 10 against Fusarium oxysporum, Fusarium graminearum and Fusarium solani strains (EC 50 4.822mg / L, 6.051mg / L and 7.743mg / L respectively) are better than oxazolidinone (EC 50 The results showed that compound 10 has great potential for further development as a novel agricultural fungicide candidate.

[0062] Table 4 EC values ​​of compounds 1-15 against three strains of Fusarium 50 and 95% confidence interval (mg / L)

[0063]

[0064]

[0065] Example 2: In vivo inhibitory effect of compound 10 on three plant pathogenic fungi of the genus Fusarium

[0066] Potato tubers were washed, then soaked in 75% alcohol for 45s, and then soaked in 2% NaClO for 10min, then dried at room temperature and cut into small pieces of 3.3cm×2.8cm×1cm. Three species of Fusarium fungi (Fusarium oxysporum, Fusarium graminearum and Fusarium laminarum) were cultured on PDA medium containing different concentrations (0, 2.5, 5, 10mg / L) of compound 10, benomyl and carbendazim for 3 days, and then a Fusarium fungus cake with a diameter of 5mm was placed in the center of each potato piece. Each experimental group included 2 replicates. After incubation at 28℃ in the dark for 3 days, the area occupied by the fungi on the potato piece was photographed and its size was measured using ImageJ software. The control effect was calculated according to the following formula:

[0067] Control effect (%) = (SS 1 ) / (SS 0 )×100%

[0068] Where S is the colony area of ​​the negative control, S 1 is the colony area of ​​potato tubers treated with the experimental compound, S 0 is the area of ​​the inoculated cake.

[0069] In vivo inhibitory effects of different concentrations of compound 10, carbendazim and chlorpyrifos on three plant pathogenic fungi of the genus Fusarium Figure 5 As shown in Table 5 and Table 7, when the concentration reaches 5 mg / L, the control effect of compound 10 on Fusarium oxysporum and Fusarium ulmoides is 69.76% and 73.16%, respectively, which is higher than the two positive controls of carbendazim (56.66% and 56.13%) and meconazole (24.04% and 60.58%); when the concentration reaches 10 mg / L, the control effect of compound 10 on Fusarium oxysporum and Fusarium ulmoides is 83.26% and 79.62%, respectively, which is better than carbendazim (82.08% and 78.95%), and slightly weaker than meconazole (84.96% and 85.21%). Figure 5 As shown in Table 6, the control effect of compound 10 at a concentration of 10 mg / L on Fusarium graminearum was 54.15%, which was slightly weaker than the two positive controls, carbendazim (63.58%) and benomyl (68.94%).

[0070] In summary, compound 10 has good control effects on three plant pathogenic fungal diseases of the genus Fusarium. At medium concentrations, its control effect on some Fusarium is better than that of existing fungicides, and at higher concentrations, its effect is comparable to that of existing chemical fungicides.

[0071] Table 5 Inhibitory effects of different concentrations of compound 10, carbendazim and chlorpyrifos on Fusarium oxysporum in potatoes

[0072]

[0073] Table 6 Inhibitory effects of different concentrations of compound 10, carbendazim and chlorpyrifos on Fusarium graminearum in potatoes

[0074]

[0075] Table 7 Inhibitory effects of different concentrations of compound 10, carbendazim and chlorpyrifos on Fusarium solani in potatoes

[0076]

[0077] Although the present invention has been disclosed as above in the form of preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. The use of phloroglucinol compounds in inhibiting the growth of mycelium of plant pathogenic fungi of the genus Fusarium, characterized in that: The phloroglucinol compound is compound 5, compound 6, compound 7, compound 8, compound 10, compound 11, compound 13 or compound 14, having the following molecular structure:

2. The use according to claim 1, characterized in that: The phloroglucinol compounds are obtained by extraction from plants or by chemical synthesis or biosynthesis.

3. The use according to claim 1, characterized in that: The plant pathogenic fungus of the genus Fusarium is Fusarium oxysporum, Fusarium graminearum or Fusarium proliferatum.

4. Use of the phloroglucinol compound of claim 1 in preventing and controlling plant diseases caused by plant pathogenic fungi of the genus Fusarium.

5. The use according to claim 4, characterized in that: The plant pathogenic fungus of the genus Fusarium is Fusarium oxysporum, Fusarium graminearum or Fusarium genus.

6. Use of a fungicide containing the phloroglucinol compound of claim 1 in inhibiting plant pathogenic fungi of the genus Fusarium.

7. Use of a pesticide containing the phloroglucinol compound of claim 1 in preventing and controlling plant diseases caused by plant pathogenic fungi of the genus Fusarium.

8. Use of the phloroglucinol compound of claim 1 in the preparation of a fungicide for inhibiting plant pathogenic fungi of the genus Fusarium.

9. Use of the phloroglucinol compound of claim 1 in the preparation of a pesticide for preventing and controlling plant diseases caused by plant pathogenic fungi of the genus Fusarium.

10. The use according to any one of claims 6 to 9, characterized in that: The plant pathogenic fungus of the genus Fusarium is Fusarium oxysporum, Fusarium graminearum or Fusarium genus.

Images