A vegetable virus preventive agent and its application

Abstract

This invention discloses a vegetable virus preventative agent and its application, belonging to the technical field of antiviral agents for vegetable diseases. The vegetable virus preventative agent includes an extract of tender willow twigs and an extract of Inonotus obliquus. The tender willow twig extract can enhance the plant's resistance to various stresses, thereby improving the antiviral ability of vegetable plants. The Inonotus obliquus extract is rich in polysaccharides, which can participate in the plant's disease defense response, synthesize polypeptides in plant cells, and have a strong ability to resist the infection and spread of various pathogens, repair cell damage, and interfere with the synthesis of viral nucleic acids and enzyme proteins, thus effectively controlling plant viruses. Treatment of vegetable seedlings with the tender willow twig extract prepared according to this invention, and treatment of plants with the Inonotus obliquus extract prepared according to this invention after destructive operations, can significantly reduce the incidence of viral diseases.

Description

Technical Field

[0001] This invention belongs to the field of antiviral agents for vegetables, specifically relating to a vegetable virus preventive agent and its application. Background Technology

[0002] In agricultural production, significant losses are incurred annually due to viral diseases affecting crops. Plant viruses are intracellular parasitic pathogens composed of nucleic acids and proteins, possessing infectious activity. They reside within plant cells. Unlike animals, plants lack their own immune systems, and once infected, they often suffer severe damage. Plant diseases caused by plant viruses are often referred to as "plant cancer." Therefore, since the discovery of viral diseases, their prevention and control have been a hot topic of research for scholars. In recent years, cucumber mosaic virus, tomato yellow leaf curl virus, and tobacco mosaic virus, among others, have caused yield reductions or even complete crop failures in many vegetables.

[0003] Due to the unique intracellular parasitic nature of plant viruses, their proliferation is integrated with the host's metabolism. Furthermore, plants lack a complete immune system, allowing viruses to survive indefinitely within plant cells once infected, until the host dies. Therefore, controlling plant viral diseases is more difficult than controlling diseases (fungi, bacteria), insects, and weeds. In addition, the diversity of plant viruses, their wide transmission routes, and the risk of transformation into novel viruses and integration into the host genome further complicate control. Currently, apart from immunizing varieties, no ideal formulation has been developed that is highly selective against viruses while being non-toxic or low-toxic to the host. Most antiviral agents developed at this stage are primarily preventative, and their efficacy is often unsatisfactory, with inhibition rates generally only reaching 30%–60% at optimal concentrations. Moreover, the limited variety of agents makes it easy for viruses to develop resistance. Therefore, finding highly effective, broad-spectrum, and safe new antiviral drugs for plants is both a challenge and a hot topic in current pesticide research. Summary of the Invention

[0004] To address the aforementioned problems in the prior art, this invention provides a vegetable virus preventative agent and its application.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] This invention provides a vegetable virus preventive agent, comprising tender willow twig extract and Inonotus obliquus extract.

[0007] Furthermore, the preparation method of the tender willow branch extract includes the following steps: collect fresh willow branches that have turned green in spring, cut them into small sections of 3-7 cm, put them into a glass or plastic container, soak them in water, then filter and sterilize the filtrate.

[0008] Furthermore, the fresh willow branches that have turned green specifically refer to willow branches from the time they sprout until they unfold their leaves; the weight ratio of willow branches to water is 1:(1.5-2.5); the soaking temperature is 18-22℃, the soaking time is 3-7 days, and then the solution is filtered through a mesh of 300 mesh or higher and the filtrate is sterilized.

[0009] Furthermore, the sterilization specifically refers to sterilization by irradiation with ultraviolet lamps.

[0010] Furthermore, the preparation method of the Inonotus obliquus extract includes the following steps: soaking Inonotus obliquus in water, filtering, and sterilizing the filtrate.

[0011] Furthermore, the mass ratio of the Inonotus obliquus to water is 1:(8-22); the soaking temperature is 40-45℃, and the soaking time is 10-15h.

[0012] Furthermore, the Inonotus obliquus is in block form, with a mass ratio of Inonotus obliquus to water of 1:(8-12), or the Inonotus obliquus is in powder form, with a mass ratio of Inonotus obliquus to water of 1:(18-22).

[0013] Furthermore, the sterilization is performed by irradiation with ultraviolet light.

[0014] This invention also provides the application of the above-described vegetable virus preventive agent in the prevention and control of vegetable viral diseases.

[0015] Furthermore, the vegetables include solanaceous vegetables and cucurbitaceous vegetables.

[0016] Further, the specific application method is as follows: During the seedling stage of vegetable crops, dilute the tender willow branch extract 20-30 times and spray it on the leaves twice, with an interval of 6-8 days between the two applications. The spraying time should be in the afternoon or evening on a sunny day. Before performing any destructive operations on the vegetable plants, dilute the birch inoculum extract 50-100 times and spray the entire plant with a sprayer. The spraying time should be in the afternoon or evening on a sunny day. Personnel engaged in destructive operations on the plants should wet their hands and gloves with an 8-12 times diluted birch inoculum extract before starting the operation.

[0017] Furthermore, the destructive operations include transplanting, grafting, bud removal, pinching, and leaf removal.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] (1) The extract of tender willow branches is rich in salicylic acid, which can induce plants to produce a variety of physiological traits such as disease resistance, salt resistance, and cold resistance. It can also directly activate the activity of many enzyme systems related to resistance. At the same time, it can also participate in the regulation of jasmonic acid metabolism in plants, enhance the plant's resistance to various stresses, and thus improve the antiviral ability of vegetable plants.

[0020] (2) The extract of Inonotus obliquus is rich in polysaccharides. Polysaccharides are a combination of sugars and proteins that have a strong ability to kill crop viruses. They can participate in the plant's disease resistance and defense response, synthesize polypeptides in plant cells, and have a strong ability to resist the infection and spread of various pathogens. They can also repair cell damage and interfere with the synthesis of viral nucleic acids and enzyme proteins, thereby playing an effective role in the prevention and control of plant viruses. Detailed Implementation

[0021] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.

[0022] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included within this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0023] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0024] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0025] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0026] The Inonotus obliquus used in the following examples is a commercially available, conventional raw material and is not particularly limited thereto. This will not be repeated below.

[0027] Example 1

[0028] The preparation steps of tender willow twig extract are as follows:

[0029] Collect fresh willow branches from the time they sprout in spring until they unfold their leaves, cut them into small sections of about 5cm, put them in a glass container, add water to the glass container according to the mass ratio of willow branches to water of 1:2, soak in a cool (18-22℃) and windproof place for 5 days, filter with a 400-mesh screen, sterilize the filtrate by ultraviolet light, and store it in a plastic bucket for later use.

[0030] Example 2

[0031] The preparation steps of Inonotus obliquus extract are as follows:

[0032] Take 1 kg of small pieces of Inonotus obliquus, put them in a glass container, add 10 kg of water, and extract for 12 hours at a water temperature of 45℃. Filter the solution through a 400-mesh screen, sterilize the filtrate by UV irradiation, and store it in a plastic bucket for later use.

[0033] Comparative Example 1

[0034] Same as Example 1, except that "fresh willow branches from spring budding to leaf unfolding" is replaced with "fresh willow branches that have not yet budded in spring".

[0035] Comparative Example 2

[0036] Same as Example 1, except that "fresh willow branches from spring budding to leaf unfolding" is replaced with "fresh willow branches after leaf unfolding".

[0037] Comparative Example 3

[0038] Same as Example 1, except that the soaking temperature is changed to 35°C.

[0039] Comparative Example 4

[0040] Same as Example 2, except the soaking temperature is changed to 55℃.

[0041] Effect verification

[0042] 1. Tomatoes face various biotic and abiotic threats, whether grown in the field or under protected cultivation. Biotic stress includes bacterial, fungal, and viral stress, with viruses having the most severe impact on plants, such as Tomato Yellow Leaf Curl Virus (TYLCV). This study aims to verify the effectiveness of the vegetable virus preventative agent prepared in this invention against TYLCV.

[0043] Tomatoes in groups A through F were used as the experimental group, and tomatoes in group G were used as the control group. Each group had 25 tomato plants, and the results were repeated three times. The corresponding treatments for each group are as follows:

[0044] Group A: During the tomato seedling stage, the tender willow branch extract prepared in Example 1 was diluted 25 times with water and sprayed on the leaves twice, with an interval of 7 days between the two applications. Spraying was done on a sunny afternoon or evening. Two days later, the phloem was inoculated with TYLCV. After transplanting the tomato seedlings, and after 7 days of recovery, the birchwood extract prepared in Example 2 was diluted 70 times and sprayed on the leaves, once every 7 days for a total of 3 applications. Spraying was done on a sunny afternoon or evening. Before transplanting, hands and gloves were soaked in a 10-fold dilution of the birchwood extract before handling the seedlings.

[0045] Groups B through F were treated the same as Group A, except that they were sprayed with different pesticides. The pesticides sprayed in each group are shown in Table 1.

[0046] Table 1. Types of pesticides sprayed in each group

[0047]

[0048] Fifteen days after the third application of the pesticide following transplanting, the incidence of TYLCV in each group of tomato plants was counted. The method for judging the disease was: the appearance of typical symptoms of viral disease: mosaic, leaf drop, or streak. The results are shown in Table 2.

[0049] Table 2. TYLCV incidence rate in tomato plants of each group

[0050]

[0051] As shown in Table 2, treatment of tomato plants with the tender willow branch extract prepared in this invention during the seedling stage and with the birch inoculum extract prepared in this invention after transplanting can improve the tomato's tolerance to TYLCV and significantly reduce the incidence of disease.

[0052] 2. Cucumbers are susceptible to cucumber mosaic virus (CMV). This study aims to verify whether the vegetable virus preventive agent prepared in this invention has a control effect on CMV.

[0053] Cucumbers in groups A through F were used as the experimental group, and cucumbers in group G were used as the control group. Each group had 25 plants, and the experiments were repeated three times. The corresponding treatments for each group are as follows:

[0054] Group A: During the cucumber seedling stage (3-4 true leaves), the tender willow branch extract prepared in Example 1 was diluted 25 times with water and sprayed on the leaves twice with an interval of 7 days. The spraying time was chosen to be in the afternoon or evening on a sunny day. Two days later, the phloem was inoculated with CMV. After transplanting the seedlings, 7 days after the seedlings had recovered, the birchwood extract prepared in Example 2 was diluted 70 times and sprayed on the leaves. The spraying was done once every 7 days, for a total of 3 times. The spraying time was chosen to be in the afternoon or evening on a sunny day. Before transplanting, hands and gloves were soaked in a 10-fold dilution of birchwood extract before handling the seedlings.

[0055] Groups B through F were treated the same as Group A, except that they were sprayed with different pesticides. The pesticides sprayed on each group are shown in Table 3.

[0056] Table 3. Types of pesticides sprayed in each group

[0057]

[0058] Fifteen days after the third application of the pesticide following transplanting, the incidence of CMV in each group of cucumber plants was counted. The method for judging the disease was: the appearance of typical symptoms of viral disease: mosaic, leaf drop, or streak. The results are shown in Table 4.

[0059] Table 4. CMV incidence rate in cucumber plants of each group

[0060]

[0061] As shown in Table 4, treatment of cucumber plants with the tender willow branch extract prepared in this invention during the seedling stage and with the birch inoculum extract prepared in this invention after transplanting can improve cucumber tolerance to CMV and significantly reduce the incidence of disease.

[0062] The above description is merely a preferred embodiment of the present invention, and the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. The application of a vegetable virus preventive agent in the control of vegetable viral diseases, characterized in that, The vegetable virus preventive agent includes tender willow branch extract and birch bark extract. The preparation method of the tender willow branch extract includes the following steps: soaking fresh willow branches that have turned green in water, then filtering and sterilizing the filtrate; the fresh willow branches that have turned green specifically refer to willow branches from budding to leaf expansion; the soaking temperature is 18-22℃; the preparation method of the birch bark extract includes the following steps: soaking birch bark in water, filtering and sterilizing the filtrate. The vegetable viral diseases mentioned are tomato yellow leaf curl virus and cucumber mosaic virus; The specific application method is as follows: During the seedling stage of vegetable crops, dilute the tender willow branch extract 20 to 30 times and spray it on the leaves twice, with an interval of 6 to 8 days between the two times; before performing destructive operations on vegetable plants, dilute the birch inoculum extract 50 to 100 times and spray it on the whole plant. The destructive operations include transplanting, grafting, bud removal, pinching, and leaf removal.

2. The application of the vegetable virus preventive agent according to claim 1 in the prevention and control of vegetable viral diseases, characterized in that, The weight ratio of willow branches to water is 1:(1.5-2.5); the time is 3-7 days.

3. The application of the vegetable virus preventive agent according to claim 1 in the prevention and control of vegetable viral diseases, characterized in that, The mass ratio of Inonotus obliquus to water is 1:(8-22); the temperature at which Inonotus obliquus is soaked in water is 40-45℃ and the time is 10-15h.

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