Application of Perphenazine in the Prevention and Treatment of Rice Blast Disease

Abstract

The present application relates to the field of rice blast prevention, and particularly relates to an application of perphenazine in prevention and treatment of rice blast. At present, perphenazine has not been reported in literatures to be used for prevention and treatment of rice blast. The technical problem to be solved by the present application is to provide an application of perphenazine in prevention and treatment of rice blast. The present application proves the effect of perphenazine in inhibiting rice blast fungus through tests. With the increase of concentration, the vegetative growth of rice blast fungus is obviously inhibited. Under the interference of perphenazine at a certain concentration, the pathogenicity of rice blast fungus is almost completely lost. Therefore, perphenazine can be used as a new antifungal agent for prevention and treatment of rice blast.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of rice blast disease prevention and treatment, and particularly relates to an application of perphenazine in prevention and treatment of rice blast disease. BACKGROUND

[0002] Magnaporthe grisea is a filamentous ascomycete fungus that causes rice blast disease. This pathogen is found in all rice-growing regions of the world and causes enough yield loss each year to feed more than 60 million people. In addition to rice, M. grisea can infect wheat, barley, sorghum and other grasses and is considered one of the most important plant pathogenic fungi. The infection cycle of M. grisea begins with the production of conidia, which are dispersed by wind or water droplets to healthy host plant tissues. Upon landing on the host plant surface, the conidia germinate to produce a germ tube under suitable conditions, which then differentiates into a spherical penetration structure, the appressorium. The appressorium further differentiates into a rigid penetration structure (infection peg) that penetrates the cuticle of the susceptible host plant and successfully invades and colonizes the host, resulting in the appearance of lesions at the infection site.

[0003] It is found that the new use of the existing drug has the characteristics of high efficiency, quickness and cost saving, and practice has proved that it is a feasible method. Perphenazine (PPZ), also known as perphenazine, is an organic compound with a chemical formula of C 21 H 26 ClN3OS, which is a drug for treating psychosis in clinic. Perphenazine has not been reported in the literature to be used for preventing and treating rice blast disease. SUMMARY

[0004] The technical problem solved by the present application is to provide an application of perphenazine in prevention and treatment of rice blast disease.

[0005] The present application is implemented as follows:

[0006] The present application provides an application of perphenazine in prevention and treatment of rice blast disease.

[0007] Specifically, the application of perphenazine in preparation of a drug for preventing and treating rice blast disease.

[0008] Further, the drug for preventing and treating rice blast disease is a single component of perphenazine as a drug or a composition of perphenazine and other pharmaceutically acceptable components as a drug.

[0009] Further, in the drug for preventing and treating rice blast disease, the concentration of perphenazine is greater than 50 μg / mL.

[0010] Preferably, the concentration of perphenazine is 50-100 μg / mL.

[0011] The present application has the following advantages: the present application proves the effect of perphenazine on inhibiting pyricularia oryzae through experiments, with the increase of concentration, the vegetative growth of pyricularia oryzae is obviously inhibited, and under the interference of perphenazine at a certain concentration, the pathogenicity of pyricularia oryzae is almost completely lost. Therefore, perphenazine can be used as a new antifungal agent for preventing and treating rice blast. BRIEF DESCRIPTION OF DRAWINGS

[0012] The present application will be further described below with reference to the drawings and specific embodiments. The present application will be further described below with reference to the drawings and specific embodiments.

[0013] Figure 1 Effect of PPZ on wild-type strain of pyricularia oryzae.

[0014] Wherein:

[0015] Sensitivity of wild-type strain to different concentrations of PPZ. Fungus was cultured on CM medium added with the specified concentration of PPZ for 10 days.

[0016] B. Analysis of the effect of PPZ on the pathogenicity of pyricularia oryzae. M. oryzae ) (5 x 10 ^4 spores / mL) was treated with DMSO, 50 μg / mL and 100 μg / mL PPZ respectively, and then sprayed on 3-week-old susceptible CO39 rice seedlings. Observation and photography were performed at 7 days post inoculation (dpi).

[0017] C. Appressorium formation of pyricularia oryzae M. oryzae after 8 hours of treatment with ddH2O, DMSO and 50 μg / mL PPZ.

[0018] D. Microscopic statistics of pyricularia oryzae infection types (Type I is appressorium, Type I is primary infection hypha, Type III is multi-forked infection hypha, and Type IV is infection hypha extending to adjacent cells) after inoculation of rice leaf sheath with conidium suspension of pyricularia oryzae added with ddH2O, DMSO and 50 μg / mL PPZ respectively for 48 h. Scale bar = 10 μm. DETAILED DESCRIPTION

[0019] The technical solutions of the present application will be described clearly and completely in combination with the drawings and specific embodiments. If specific conditions are not specified in the examples, conventional conditions or manufacturer's recommended conditions are used. If the reagents or instruments used are not specified by the manufacturer, they are all conventional products that can be purchased on the market.

[0020] I. Materials and methods

[0021] Strains

[0022] (1) The wild type strain of Magnaporthe grisea used in this study is Guy 11.

[0023] (2) Rice variety CO39.

[0024] Common medium (per liter)

[0025] (1) CM medium: Yeast extract and acid hydrolysis casein each 6 g, sucrose 10 g, agar powder 20 g.

[0026] (2) Rice bran medium: Rice bran 40 g, agar powder 20 g, pH 6.0-6.5.

[0027] II. Basic phenotype analysis of Magnaporthe grisea

[0028] The following experiments are repeated more than three times.

[0029] 1 Growth rate determination

[0030] Fresh mycelial plugs of the same size of the wild type, mutant and complementary strains are cut and inoculated in the center of 9 cm CM solid medium, 5 parallel repeats for each strain, 28°C inverted culture for 7 days, the colony diameter is measured and photographed.

[0031] 2 Conidial germination and appressorium formation observation

[0032] The spore solution is filtered by two layers of lens paper, the spore solution concentration is adjusted to 1×104-3×104 spores, 20 μL is added to the center of a hydrophobic slide, and the conidial germination and appressorium formation are observed by microscope or confocal after 2 h, 4 h, 8 h, 16 h dark and moist culture.

[0033] 3 Rice pathogenicity observation

[0034] The spore solution is filtered by two layers of lens paper, the spore solution concentration is adjusted to 2×10 4 -5×10 4 , 0.02% Tween 20 is added, mixed and sprayed to inoculate rice CO39 at the three-leaf-one-heart stage, after 24 h dark and moist culture, it is transferred to natural conditions for 4-6 d moist culture, the rice samples are investigated after the wild type shows lesions, and scanned and saved.

[0035] III. Test results

[0036] In terms of the control of Magnaporthe oryzae, we first detected the sensitivity of wild-type strain to PPZ. The results showed that the growth rate of wild-type strain on DMSO, the negative control group, was similar to that of the blank group Mock after 7 days of culture, with a diameter of about 57 mm. However, when different concentrations of PPZ were added, the wild-type strain showed dose-dependent sensitivity to PPZ. As the concentration increased, the vegetative growth of M. oryzae was significantly inhibited. The calculated EC 50 value of PPZ was 41 μg / mL. Figure 1

[0037] To determine the effect of PPZ on the infection ability of M. oryzae, we pre-treated the spore suspension of Guy11 strain with 50 μg / mL and 100 μg / mL of PPZ, respectively, and then sprayed it on CO39 rice seedlings. The results showed that the DMSO group of rice leaves showed obvious fusiform lesions, while the rice leaves treated with 50 μg / mL and 100 μg / mL of PPZ had almost no significant lesions, only a small amount of hypersensitive necrotic lesions, and the pathogenicity of M. oryzae was almost completely lost Figure 1 B).This indicates that PPZ interferes with the pathogenicity of M. oryzae.

[0038] To clarify the specific mechanism of PPZ affecting the infection ability of M. oryzae, we first observed the effect of PPZ on the germination process of appressoria. The results showed that after 8 h of induction, the appressorium germination rate of M. oryzae conidia in the Mock and DMSO groups reached more than 98%, while the M. oryzae conidia treated with 50 μg / mL of PPZ could hardly germinate to form appressoria, indicating that PPZ inhibits the germination process of M. oryzae appressoria Figure 1 C).

[0039] Infection hyphae are the infection organs of M. oryzae that penetrate into rice cells. The expansion ability of M. oryzae can be quantified according to the different proportions of infection hyphae levels. Type I is the appressorium of M. oryzae that has not penetrated the rice cells, Type II is the single or initial bifurcated infection hyphae, Type III is the multi-bifurcated but not yet infected to the lower cells, and Type IV is the infection hyphae that have invaded other cells. Statistical analysis found that after 48 h of inoculation, the Mock and DMSO groups were mostly Type IV infection hyphae, while the leaf sheath group treated with 50 μg / mL of PPZ was mostly Type I infection hyphae, indicating that PPZ inhibits the penetration level of M. oryzae expansion ability Figure 1The infection ability of the rice blast fungus was limited by the use of PPZ, and the rice blast fungus could not effectively infect the rice, i.e., the prevention and treatment effect was achieved.

[0040] The above results show that PPZ can be used as a new antifungal agent for preventing and treating rice blast.

[0041] Although the specific embodiments of the present application are described above, it should be understood by those skilled in the art that the specific examples described are illustrative only and not intended to limit the scope of the present application, and equivalent modifications and variations made in accordance with the spirit of the present application should be covered by the scope of protection of the claims of the present application.

Claims

1. The use of perphenazine in the prevention and treatment of rice blast, characterized in that: The application of the Perphenazine in the preparation of the medicine for preventing and treating rice blast, the concentration of the Perphenazine in the medicine for preventing and treating rice blast is 50 μg / mL-100 μg / mL.

2. Use according to claim 1, characterized in that: The medicine for preventing and treating rice blast is the single component of the Perphenazine or the composition of the Perphenazine and other pharmaceutically acceptable components.

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