Preparation for preventing and controlling tobacco mosaic disease and application thereof

Abstract

The present invention belongs to the technical field of prevention and control of tobacco mosaic disease, specifically discloses a preparation and application thereof for preventing and controlling tobacco mosaic disease, and is composed of the following components: yeast polysaccharide 1.5-1.9 g / L, glycyrrhizic acid 1.3-1.7 g / L, sodium cholate 0.7-1.1 g / L, and the remainder is water. Compared with the prior art, the inducer prepared by the present invention, which is composed of three components of yeast polysaccharide, glycyrrhizic acid and sodium cholate, has an inducing effect on tobacco mosaic virus TMV, cucumber mosaic virus CMV and potato Y virus PVY, and has a promoting effect on tobacco growth, and is better than the existing plant immunity inducer Ata Ling. In production, the inducer of the present invention can be applied to the prevention and control of tobacco mosaic disease in the field by spraying, and can also be used for the prevention and control of tobacco seedling virus disease, and its antiviral effect has the characteristics of high efficiency and harmlessness to plants; low cost, convenient operation of tobacco farmers, and strong application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of prevention and control of tobacco mosaic disease, in particular to a preparation for preventing and controlling tobacco mosaic disease and application thereof. Background Art

[0002] Tobacco mosaic virus (TMV), cucumber mosaic virus (CMV), and potato virus Y (PVY) are the main viruses that infect tobacco. The viral diseases caused by them cause huge economic losses to the tobacco industry every year. TMV is a member of the Virgaviridae family and the Tobamovirus genus. It is a positive single-stranded RNA virus, and its virions are straight rod-shaped particles with a diameter of about 18nm and a length of about 300nm. CMV is a member of the Bromoviridae family and the Cucumovirus genus. The virions are spherical in structure, and the genome consists of three positive single-stranded RNAs. PVY is a typical member of the Potyviridae family and the Potyvirus genus. The virions are linear and curved, and the viral genome consists of one positive single-stranded RNA.

[0003] At present, the prevention and control measures for tobacco mosaic disease mainly include agricultural control, chemical control, biological control, plant immune inducer control and other methods. Plant immune inducers are environmentally friendly green pesticides that have the functions of improving plant resistance and promoting plant growth. They can be used as plant vaccines to induce the plant's own immune system to achieve the purpose of plant disease resistance. Common plant immune inducers include salicylic acid (SA), jasmonic acid (JA), benzothiadiazole (BTH), etc. They all have the characteristics of long-lasting and stable resistance, broad spectrum, and no pollution. According to different sources, plant immune inducers can be divided into biogenic inducers and non-biogenic active molecules. According to the type, they can be divided into organic acids, inorganic compounds, oligosaccharides and protein peptides, as well as plant immune inducers: Trichoderma and Bacillus.

[0004] Plant immune inducers do not have the function of directly inactivating pathogens. Their mechanism of action is to induce plants to activate their own immune systems, allowing plants to produce defense responses and promote resistance to pathogens. Many plant immune inducers have a growth-promoting effect on plants, promoting root growth, cell division, bud differentiation, increasing tillering and the number of grains per ear. After application, the plant's physiological indicators such as plant height, stem girth, and root length are higher than those of conventionally grown plants. Immune inducers usually increase the accumulation of hormones related to plant growth and development during the seedling stage, increase the enzyme activity of plants, enhance photosynthesis, etc., so that plants can grow better and faster.

[0005] Yeast polysaccharide is a high molecular weight polysaccharide substance that is anti-tumor, stimulates and enhances the human immune function. Glycyrrhizic acid is an extract from the root of licorice, which has anti-inflammatory effects. Both agents are used in the study of human or animal diseases. Sodium cholate is an organic metal salt formed by the combination of bile acid and sodium ions. It is easily soluble in water and alcohol. It is a non-denaturing detergent and surfactant, mainly used in medicine, animal husbandry and industry.

[0006] CN202310320715.4 discloses a biocontrol agent for preventing and controlling tobacco fungal diseases and a control method thereof, and relates to the technical field of pesticides. The biocontrol agent of the present invention comprises bacillus powder and a synergist; wherein the synergist is a mixture of puerarin, glycyrrhizic acid, aloin, and rhein in a mass ratio of 3 to 8:1 to 2:5 to 10:1 to 2; and the proportion of bacillus powder in the biocontrol agent is 1 to 10wt.%; the proportion of the synergist in the biocontrol agent is 0.5-2.5wt.%. It can promote the germination of bacillus spores, improve the survival rate of biocontrol bacteria, and its control effect on pathogens in the field.

[0007] CN201710421948.8 discloses that yeast polysaccharide has a preventive effect on various plant virus diseases, such as tobacco mosaic virus disease, wheat yellow dwarf virus disease or rice stripe virus disease, etc. Yeast polysaccharide can be prepared into a pharmaceutical composition by a method known in the prior art, as well as any pesticide-acceptable dosage form, such as an aqueous solution, a soluble liquid, an emulsifiable concentrate, a microemulsion, a suspension, an aqueous emulsion, a wettable powder or a water-dispersible granule pharmaceutical composition, etc.

[0008] The above schemes disclose glycyrrhizic acid and yeast polysaccharide for the prevention and treatment of tobacco mosaic disease, but none of them discloses the use of sodium cholate for the prevention and treatment of tobacco mosaic disease; and the above schemes cannot simultaneously prevent and control tobacco mosaic virus TMV, cucumber mosaic virus CMV, and potato virus Y PVY. Summary of the invention

[0009] In order to solve the above technical problems, the present invention provides a preparation for preventing and controlling tobacco mosaic disease and its application.

[0010] To achieve the above object, the present invention is implemented according to the following technical solutions:

[0011] One of the purposes of the present invention is to provide a preparation for preventing and controlling tobacco mosaic disease, which is composed of the following components: 1.5-1.9 g / L of yeast polysaccharide, 1.3-1.7 g / L of glycyrrhizic acid, 0.7-1.1 g / L of sodium cholate, and the balance is water.

[0012] Preferably, the preparation for preventing and controlling tobacco mosaic disease consists of the following components: 1.7 g / L yeast polysaccharide, 1.5 g / L glycyrrhizic acid, 0.9 g / L sodium cholate, and the balance is water.

[0013] The second object of the present invention is to provide a preparation for preventing and controlling tobacco mosaic disease for use in preparing an inducer that is highly resistant to tobacco mosaic virus TMV, cucumber mosaic virus CMV, and potato virus Y PVY.

[0014] The third object of the present invention is to provide an inducer which is highly resistant to tobacco mosaic virus TMV, cucumber mosaic virus CMV and potato virus Y PVY, which is composed of the above-mentioned preparations for preventing and controlling tobacco mosaic disease.

[0015] The fourth object of the present invention is to provide an application of the above-mentioned inducer in the prevention and control of tobacco mosaic disease in the field, specifically, including:

[0016] S1. During the big cross stage of tobacco seedlings, spray the surface of tobacco leaves with the inducer once;

[0017] S2. Plant the healthy tobacco plants grown in step S1 in the field according to conventional cultivation methods, and spray the surface of the tobacco leaves with the inducer once before the tobacco plants grow to the rooting stage, i.e., the clumping stage; and spray the surface of the tobacco leaves with the inducer once before the tobacco plants grow to the vigorous growth stage, i.e., the budding stage.

[0018] Compared with the prior art, the inducer prepared by the present invention, which is composed of three components, yeast polysaccharide, glycyrrhizic acid and sodium cholate, has an inducing effect on tobacco mosaic virus TMV, cucumber mosaic virus CMV and potato virus Y PVY, and has a promoting effect on tobacco growth, and is superior to the existing plant immunity inducer Ata Ling. In production, the inducer of the present invention can be applied to the prevention and control of tobacco mosaic disease in the field by spraying, and can also be used for the prevention and control of tobacco virus diseases in the seedling stage. Its antiviral effect has the characteristics of high efficiency and harmlessness to plants; it is low in cost, convenient for tobacco farmers to operate, and has a strong application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The disease conditions of tobacco plants in different treatment groups 14 days after inoculation with TMV: a, tobacco plants in the negative control group; b, tobacco plants in the group treated with the agent of Example 2; c, tobacco plants in the positive control group.

[0020] Figure 2 The growth conditions of tobacco plants in different treatment groups after inoculation with TMV for 20 days: left figure: comparison of tobacco plant height; right figure: comparison of tobacco plant root length; the left sides of both figures are tobacco plants in the group treated with the agent of Example 2, and the right sides are tobacco plants in the negative control group.

[0021] Figure 3 The disease conditions of tobacco plants in the field after being treated with the agent of Example 2 using the second treatment method: the left side shows tobacco plants in the group treated with the agent of Example 2; the right side shows tobacco plants in the negative control group.

[0022] Figure 4 The growth conditions of tobacco plants in the field after being treated with the agent of Example 2 using the second treatment method: the left side is the tobacco plants of the positive control group; the middle is the tobacco plants of the negative control group; and the right side is the tobacco plants of the group treated with the agent of Example 2. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the invention.

[0024] Example 1: A preparation for preventing and controlling tobacco mosaic disease, consisting of the following components: 1.5 g / L yeast polysaccharide, 1.3 g / L glycyrrhizic acid, and 0.7 g / L sodium cholate, all of which are mixed and dissolved in water.

[0025] Example 2: A preparation for preventing and controlling tobacco mosaic disease, consisting of the following components: 1.7 g / L yeast polysaccharide, 1.5 g / L glycyrrhizic acid, and 0.9 g / L sodium cholate, all of which are mixed and dissolved in water.

[0026] Example 3: A preparation for preventing and controlling tobacco mosaic disease, consisting of the following components: 1.9 g / L yeast polysaccharide, 1.7 g / L glycyrrhizic acid, 1.1 g / L sodium cholate, all of which are mixed and dissolved in water.

[0027] Comparative Example 1: A preparation for preventing and controlling tobacco mosaic disease, consisting of the following components: 1.3 g / L yeast polysaccharide, 1.1 g / L glycyrrhizic acid, and 0.5 g / L sodium cholate, all of which are mixed and dissolved in water.

[0028] Comparative Example 2: A preparation for preventing and controlling tobacco mosaic disease, consisting of the following components: 2.1 g / L yeast polysaccharide, 1.9 g / L glycyrrhizic acid, and 1.3 g / L sodium cholate, all of which are mixed and dissolved in water.

[0029] In order to verify whether the above-mentioned preparation for preventing and controlling tobacco mosaic disease can be used to prepare an inducer that is highly resistant to tobacco mosaic virus TMV, cucumber mosaic virus CMV, and potato virus Y PVY, the following experiment was conducted:

[0030] 1. Potted Plant Experiment

[0031] Experimental materials were selected. The seeds of the common tobacco variety Yunyan 87 were provided by the Plant Virus Research Laboratory of South China Agricultural University. Tobacco plants were obtained by conventional seedling cultivation of tobacco seeds, and tested to be virus-free. The test viruses TMV (common strain), CMV (common strain), and PVY (common strain) were all provided by the Plant Virus Research Laboratory of South China Agricultural University. Yeast polysaccharide was purchased from Shaanxi Haochen Biotechnology Co., Ltd., glycyrrhizic acid was purchased from Gansu Panzhi Pharmaceutical Co., Ltd., and sodium cholate was purchased from Jiangsu Caiwei Biotechnology Co., Ltd.

[0032] At the big cross stage of tobacco seedlings, the young leaves of tobacco plants were sprayed with the agents of Examples 1 to 3, Comparative Example 1, and Comparative Example 2 as the agent treatment group, and at the same time, they were treated with Atailing (0.75 mg / mL) as the positive control group CK+, and the water treatment was used as the negative control group CK-; 20 tobacco plants were treated with each agent. After 24 hours of induction, the viruses TMV / CMV / PVY were inoculated (the virus inoculation concentration was 3.47×10 8 100 copies / μL), 7 days after inoculation, the systemic leaves above the inoculated leaves were taken, RNA was extracted, and the expression of the virus was detected by fluorescent quantitative PCR; 28 days after inoculation, the disease index of the tobacco plants was counted and the relative prevention effect was calculated. The disease resistance effects of different formulations were analyzed and compared, and the best formulation was selected for field experiments. The tobacco disease severity classification standard adopts the tobacco disease and insect pest classification and investigation method: GB / T23222-2008.

[0033] The calculation formulas for disease index and relative prevention efficacy are as follows:

[0034] Disease index = ∑ (number of diseased plants at each level × value of the disease level) / (total number of plants surveyed × highest level value) × 100;

[0035] Relative protective effect (%) = (disease index of control - disease index of treatment) / disease index of control × 100;

[0036] Take another tobacco plant treated with the drug and culture it normally without inoculating the virus. After 20 days, measure the plant height, root length, and total fresh weight of the tobacco and calculate their average values. Analyze the growth-promoting effect of the drug on the tobacco plant. The determination method is carried out in accordance with the "Methods for Measuring Agronomic Traits of Tobacco" (YC / T142-2010).

[0037] The virus content in the tobacco leaves 7 days after the treatment is shown in Table 1. Figure 1The disease occurrence of tobacco plants in different treatment groups 14 days after inoculation with TMV is shown.

[0038] Table 1 Statistics of virus content in tobacco strains 7 days after treatment with pesticides

[0039]

[0040] Note: Different lowercase letters in the same column indicate significant differences (P<0.05).

[0041] The experimental results show that the agents of Examples 1 to 3 can induce strong virus resistance after treating tobacco plants. Among them, the agent of Example 2 has the best induction effect, which is better than the induction effect of Atailing. The induction effect of the agents of Comparative Examples 1 and 2 after treating tobacco plants is not good.

[0042] The incidence of tobacco mosaic disease 30 days after the treatment is shown in Table 2.

[0043] Table 2 Statistics of disease incidence of tobacco plants after treatment with pesticides

[0044] deal with Disease index Relative protection effect (%) Comparative Example 1 65.16 b 30.64 c Example 1 19.98 a 70.34 b Example 2 10.65 a 80.37 a Example 3 17.55 a 75.65 b Comparative Example 2 60.82 b 35.84 c Clear water (CK-) 71.72 c Atai Ling (CK+) 14.98 a 78.87 b

[0045] Note: Different lowercase letters in the same column indicate significant differences (P<0.05).

[0046] The experimental results show that the agents of Examples 1 to 3 can induce strong virus resistance in tobacco plants, among which the agent of Example 2 has the best resistance induction effect, and its relative protection effect is better than that of Ata Ling.

[0047] The growth of tobacco plants 20 days after treatment is shown in Table 3. Figure 2 .

[0048] Table 3 Statistics of tobacco plant growth after treatment with pesticides

[0049] deal with Plant height (cm) Root length (cm) Fresh weight (g) Comparative Example 1 25.2±1.90 b 14.9.6±1.1 0 c 14.7±0.8 c Example 1 33.04±1.25 a 16.6±0.86 c 14.5±0.8 c Example 2 35.94±1.40 a 18.4±1.34 a 18.4±1.54 a Example 3 30.53±4.82 a 17.9±1.89 a 16.8±0.68 b Comparative Example 2 28.89±2.22 b 16.2±0.56 b 14±1.35 c Clear water (CK-) 19.5±1.06 c 13.6±0.8 c 13.5±0.8 d Atai Ling (CK+) 31.2±1.40 a 16.6±1.1 b 16.7±0.8 b

[0050] Note: Different lowercase letters in the same column indicate significant differences (P<0.05).

[0051] The experimental results show that the agents of Examples 1 to 3 all have good growth-promoting effects on tobacco seedlings after being treated. Among them, the agent of Example 2 has the best growth-promoting effect, which is better than the growth-promoting effect of Atai Ling.

[0052] Therefore, the pesticides in subsequent field tests were used to treat tobacco plants using the pesticides of Examples 1 to 3.

[0053] 2. Field Experiment

[0054] A field with an area of ​​1 mu where tobacco is planted all year round was selected at the Ningxi Experimental Base in Zengcheng, Guangzhou. Healthy tobacco plants that had been cultivated before were selected and planted in the field according to conventional cultivation methods. The row spacing between each row of tobacco plants was 1.3-1.5m, and the plant spacing was 0.8-1.0m. The tobacco plants were treated with agents at different growth stages. The agents of Examples 1 to 3 were sprayed on the tobacco leaf surface respectively, and Atailing (0.75 mg / mL) was used as the positive control group CK+, and clean water was used as the negative control group CK-; the treatment time is shown in Table 4; 80 tobacco seedlings were treated with each agent. Samples were taken during the tobacco leaf harvest period, and the expression of the virus was detected by fluorescent quantitative PCR; the disease index of the tobacco plants was counted and the relative prevention effect was calculated. The classification standard for tobacco disease severity, the disease index, and the calculation method of the relative prevention effect were the same as those of the potted experiment. Analyze and compare the anti-mosaic effect of different agent formulations and different treatment methods; and the growth index of the tobacco plants was counted during the tobacco leaf harvest period. The determination method was the same as that of the potted experiment.

[0055] Table 4 Field treatment methods

[0056] Processing Specific time Type 1 All agents (including negative and positive controls) were treated once. Treatment was performed once during the rooting stage (before the clustering stage). Type 2 All agents (including negative and positive controls) were treated twice, once in the rooting stage (before the clustering stage) and once in the vigorous growth stage (before the budding stage). Type 3 All agents (including negative and positive controls) were treated twice, once in the rooting stage (before the clustering stage) and once in the maturity stage (after the budding stage).

[0057] The occurrence of mosaic disease and virus content in tobacco plants at the harvest stage under different treatments are shown in Figure 5.

[0058] Table 5 The occurrence of mosaic disease and virus content in tobacco plants at harvest under different treatments

[0059]

[0060] Note: Different lowercase letters in the same column indicate significant differences (P<0.05).

[0061] As shown in Table 5, under different treatment methods, compared with the clean water control, the second treatment method has the lowest detection rate of toxic tobacco strains and the lowest content of TMV / CMV / PVY, and the overall effect is better than the treatment effect of Atelin. The first and third treatment methods also have antiviral effects, and the overall effect is slightly inferior to the treatment effect of Atelin. Among each treatment method, the antiviral effect of the agent of Example 2 is the best, which is better than the treatment effect of Atelin.

[0062] Then, the disease incidence of tobacco plants under the second treatment method was statistically analyzed in detail, and the disease index and relative prevention effect were calculated. The specific data are shown in Table 6.

[0063] Table 6 Statistics of disease index and relative efficacy of the second treatment on tobacco plants against mosaic disease in the field

[0064] Pharmacy Disease index Relative protection effect (%) Example 1 31.59 b 61.03 b Example 2 26.89 c 74.45 a Example 3 28.26 c 65.34 b Artelin 28.67 c 66.24 b Shimizu 81.22 a

[0065] Note: Different lowercase letters in the same column indicate significant differences (P<0.05).

[0066] As shown in Table 6, the disease index of tobacco plants treated with the agent of Example 2 was the lowest, and the relative prevention effect was the highest, which was better than the relevant data of Atailing. Figure 3 ,Depend on Figure 3 It can be seen that the leaves of the tobacco plants treated with the agent of Example 2 are flat and smooth, with almost no lesions. Figure 3 The tobacco plant on the left in the middle; the tobacco plant in the negative control group had wrinkled leaves and darker blisters. Figure 3 The tobacco plant on the middle right.

[0067] Furthermore, the growth indexes of tobacco plants under the second treatment were investigated in detail. The specific data are shown in Table 7.

[0068] Table 7 Statistics of tobacco plant growth indicators under the second treatment method

[0069] Pharmacy Plant height (cm) Stem circumference (cm) Number of blades Maximum leaf length (cm) Maximum leaf width (cm) Example 1 107.1±2.3 b 14.0±1.3 b 16.5±0.3 b 89.9±0.1 b 26.4±1.1 c Example 2 110.8±0.3 a 14.2±2.3 b 17.1±1.3 a 90.3±2.0 a 28.6±0.3 a Example 3 107.5±3.2 b 14.5±2.1 a 17.1±0.9 a 89.0±1.3 b 27.3±0.4 b Artelin 103.0±1.3 b 14.00±2.0 b 17.2±1.7 a 89.7±1.6 b 26.8±1.8 c Shimizu 90.7±0.6 c 13.2±1.0 c 16.6±0.3 b 86.5±0.4 c 24.4±0.4 d

[0070] Note: Different lowercase letters in the same column indicate significant differences (P<0.05).

[0071] The agents of Examples 1 to 3 all have a good growth-promoting effect on tobacco plants; all survey indicators are equivalent to or better than the growth-promoting effect of Atai Ling on tobacco plants. The agent of Example 2 has the best growth-promoting effect, as shown in Figure 2. Figure 4 , the left side is the tobacco plant treated with Ata Ling, the middle side is the tobacco plant treated with clean water, and the right side is the tobacco plant treated with the agent of Example 2.

[0072] In summary, the inducer prepared by the present invention, which is composed of three components, yeast polysaccharide, glycyrrhizic acid and sodium cholate, has an inducing effect on tobacco mosaic virus TMV, cucumber mosaic virus CMV and potato virus Y PVY, and has a promoting effect on tobacco growth, and is superior to the existing plant immunity inducer Ata Ling. In production, the inducer of the present invention can be applied to the prevention and control of tobacco mosaic disease in the field by spraying, and can also be used for the prevention and control of tobacco seedling virus diseases. Its antiviral effect has the characteristics of high efficiency and harmlessness to plants; low cost, convenient operation by tobacco farmers, and strong application prospects.

[0073] The technical solution of the present invention is not limited to the above-mentioned specific embodiments. All technical variations made according to the technical solution of the present invention fall within the protection scope of the present invention.

Claims

1. An inducer that is simultaneously resistant to tobacco mosaic virus TMV, cucumber mosaic virus CMV and potato virus Y PVY, It is characterized in that It is composed of the following components: yeast polysaccharide 1.7 g / L, glycyrrhizic acid 1.5 g / L, sodium cholate 0.9 g / L, and the balance is water.

2. Use of the inducer as claimed in claim 1 in the preparation of an inducer that is resistant to tobacco mosaic virus TMV, cucumber mosaic virus CMV and potato virus Y PVY.

3. Use of the inducer as claimed in claim 1 that is resistant to tobacco mosaic virus TMV, cucumber mosaic virus CMV and potato virus Y PVY in the prevention and control of tobacco mosaic disease in the field.

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