Method for preventing powdery mildew on plants and method for washing away powdery mildew spores

Abstract

To provide a method for preventing plant disease that can prevent the occurrence of plant disease reliably and readily.SOLUTION: A method for preventing the occurrence of plant disease includes spraying a plant leaf with liquid including water so that the force received by the leaf 1 cm2 becomes 0.002 N or greater.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to methods for preventing various plant diseases. [Background technology]

[0002] In the field of agriculture and horticulture, plant diseases are a problem, and the control of plant diseases by spraying fungicides, for example, is widely practiced. There are various synthetic fungicides available for spraying, and some of these synthetic fungicides have systemic properties and exhibit residual activity, so spraying such fungicides in advance can effectively control plant diseases. However, there is also a need to avoid using synthetic fungicides as much as possible, especially in home gardening.

[0003] Therefore, efforts are being made to prevent plant diseases without using fungicides. One example is maintaining humidity by watering plants appropriately to prevent powdery mildew.

[0004] There is also known a technique for controlling powdery mildew by spraying nanobubble water, as disclosed in Patent Document 1. Patent Document 1 shows that the occurrence of powdery mildew was suppressed by using nanobubble water for watering the soil. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Republished Publication No. 2019 / 230789 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when it comes to preventing powdery mildew by maintaining humidity through moderate watering, it is difficult to say that this method is effective in preventing plant diseases, and there is also the problem that raising the humidity too much can induce other diseases.

[0007] Furthermore, the method of spraying nanobubble water described in Patent Document 1 is excellent in that it can control plant diseases without using synthetic fungicides, but since a dedicated device is required to generate nanobubble water, it cannot be said that this method can be easily implemented in home gardening.

[0008] Therefore, the inventors of the present invention have investigated a method for more reliably and easily preventing the occurrence of plant diseases. After extensive investigation, they discovered that the onset of powdery mildew can be prevented by applying a liquid to plant leaves with a specific force, and have completed the present invention.

[0009] An object of the present invention is to provide a method for preventing plant diseases that can reliably and easily prevent the occurrence of plant diseases. [Means for solving the problem]

[0010] In order to achieve the above object, the method for preventing the onset of a plant disease according to the present disclosure comprises applying a 1 cm of fertilizer to a plant leaf. 2 It sprays a liquid containing water so that the force applied to the object is 0.002N or more.

[0011] This configuration makes it possible to wash away fungal spores adhering to leaf surfaces with the liquid, thereby preventing the occurrence of plant diseases. This method is effective in preventing disease even one day after the fungal spores have been attached to the leaves. This method is a simple preventive method that can be carried out in addition to daily watering, and can also be used in conjunction with spraying insecticides and fungicides if necessary, making it extremely useful in home gardening.

[0012] The disease to be prevented may be powdery mildew. In this case, the liquid can be sprayed onto the leaves of plants that may develop powdery mildew. This allows the powdery mildew spores to be washed away. Since powdery mildew spores are said to begin penetrating host cells within a few hours of adhering to the leaf and to mature into haustoria 20 hours later, it is completely unexpected that the onset of the disease can be prevented simply by applying the liquid with the above-mentioned force even one day after inoculation.

[0013] By spraying the liquid with a specified force 24 hours or more after the powdery mildew spores have attached to the plant leaves, powdery mildew spores after the haustoria have matured can also be washed away.

[0014] The liquid can be sprayed once or multiple times within a period of, for example, six days or less. In other words, since powdery mildew spores are believed to produce conidia about six days after they attach to the leaves, repeated washing at shorter intervals than this allows the spores to be washed away before they produce conidia, thereby increasing the effectiveness of preventing the onset of powdery mildew.

[0015] The liquid may contain an insecticidal or fungicidal component derived from a food ingredient. This allows the insecticidal or fungicidal component to be sprayed while preventing powdery mildew according to the present invention. Since synthetic pesticide components are subject to limitations on the number of times they can be sprayed on plants, repeated spraying within a period of six days or less is inappropriate. In contrast, insecticidal or fungicidal components derived from food ingredients generally do not have such limitations, making them suitable for application in the present invention.

[0016] The liquid can also be sprayed by a spray device having a hand-operated pump, meaning that the method of the present invention can also be carried out by hand spraying, making it a convenient method particularly suitable for home gardening.

[0017] The liquid can also be sprayed from a spray nozzle positioned at a distance of 20 cm or less from the leaves. [Effects of the Invention]

[0018] As described above, by spraying a liquid containing water with a predetermined force onto the leaves of a plant, it is possible to reliably and easily prevent the occurrence of plant diseases. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a side view of a hand sprayer used in a method for preventing plant diseases according to an embodiment. [Figure 2] FIG. 1 is a diagram illustrating the spraying of liquid onto leaves using a hand sprayer. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the following description of the preferred embodiments is merely exemplary in nature and is not intended to limit the present invention, its applications, or its uses.

[0021] FIG. 1 is a side view of a hand sprayer 1 used in a method for preventing plant diseases according to an embodiment of the present invention. The hand sprayer 1 includes a container 2 that contains a liquid used in the method for preventing plant diseases, and a spray device 3. It may also be called, for example, a hand spray product or a product for preventing plant diseases. An opening (not shown) is formed in the top of the container 2. The spray device 3 is attached to the top of the container 2 and has a pump 4 that can be operated by hand. The upper end of a tube 5 extending vertically is connected to the suction port of the pump 4. The tube 5 is inserted inside the container 2 and is configured to be able to suck in the liquid contained in the container 2.

[0022] The upstream end of a discharge pipe 7 is connected to the discharge port of the pump 4. The downstream end of the discharge pipe 7 is formed as a nozzle 7a that opens toward the front of the hand sprayer 1. The nozzle 7a may be a spray nozzle that sprays the liquid in a mist, or a nozzle that sprays the liquid in a shower-like manner. The number of nozzles 7a may be one or more.

[0023] The spray device 3 includes a trigger 6 as an operating unit operated by the user. The trigger 6 extends vertically, and its upper end is supported by a support shaft 6a so as to be rotatable about a horizontal axis relative to the main body of the spray device 3. The trigger 6 is connected to the pump 4 via an operating rod (not shown). The user can operate the pump 4 by engaging and pulling the trigger 6 with their finger. When the pump 4 is activated, the liquid contained in the container 2 is drawn up from the lower end of the tube 5 and sprayed from the nozzle 7a of the discharge pipe 7. The amount of liquid sprayed from the nozzle 7a by one pull of the trigger 6 (the amount sprayed per trigger operation) can be set to, for example, 0.3 ml or more, 0.6 ml or more, 0.9 ml or more, or 1.2 ml or more. The amount sprayed per trigger operation can be set to any amount by, for example, adjusting the opening area of ​​the nozzle 7a or adjusting the discharge rate and spray amount of the pump 4. The upper limit of the amount of ejection per trigger operation can be set to, for example, 0.4 ml or less, 0.7 ml or less, 1.0 ml or less, or 1.3 ml or less.

[0024] The spray device 3 may be an electric type equipped with, for example, an electric motor. In this case, a battery for supplying power to the electric motor and an ON / OFF switch for manual operation by the user may be provided.

[0025] The liquid contained in the container 2 contains at least water. The water may be purified water or tap water supplied from a general water supply. The liquid may consist of only water or may contain components other than water. Examples of components other than water include insecticidal or bactericidal components derived from food ingredients, specifically sorbitan fatty acid esters. The amount of sorbitan fatty acid ester contained in the liquid is not particularly limited, but is, for example, 0.01% by mass to 1.0% by mass, preferably 0.1% by mass to 0.5% by mass. When the liquid contains components other than water, it can be distributed on the market as a concentrated liquid. Users can obtain the liquid by purchasing the concentrated liquid and diluting it with water. Furthermore, since the liquid is used to prevent the onset of plant diseases, it can also be called a disease prevention agent. Furthermore, since the liquid can wash away disease-causing bacteria and spores from leaves, it can also be called a wash-off agent.

[0026] (Methods for preventing plant diseases) Next, a method for preventing the onset of plant diseases will be specifically described. First, a hand sprayer 1 containing the liquid in a container 2 is prepared. This is the preparation step. Then, as shown in FIG. 2, the hand sprayer is applied to the leaves of the plant so that the liquid is applied to the leaves in an amount of 1 cm. 2The liquid is sprayed so that the force applied to the surface of the plant is equal to or greater than a predetermined force. The predetermined force is, for example, 0.002 N or 0.003 N. The upper limit of the predetermined force can be, for example, 0.02 N or 0.01 N. This is the spraying step. In the spraying step, the liquid is sprayed onto plants for which disease onset is desired to be prevented. For example, the liquid can be sprayed onto the leaves of plants susceptible to powdery mildew. Examples of plants susceptible to powdery mildew include vegetables, potatoes, beans, and ornamental plants. The liquid can also be sprayed onto other plants. The liquid can also be sprayed onto plants that do not suffer from powdery mildew but may suffer from other diseases. Specifically, the liquid is preferably sprayed onto plants that may suffer from disease due to fungi or molds attached to the leaves. It is also effective to spray the liquid during times or in areas where disease onset is more likely.

[0027] By changing the amount of spray per trigger operation, the shape and opening area of ​​the nozzle 7a, etc., the amount of spray per 1cm of leaf surface can be increased. 2 The force received by the nozzle 7a can be adjusted by changing the amount of spray per trigger operation, the shape and opening area of ​​the nozzle 7a, etc., so that the amount of spray per unit time from the nozzle 7a can be increased. 2 On the other hand, by changing the amount of spray per trigger operation, the shape and opening area of ​​the nozzle 7a, etc., the amount of spray per unit time from the nozzle 7a can be reduced, and the amount of spray per 1cm of leaf surface can be reduced. 2 The force applied to the leaf surface is reduced by the force applied to the trigger 6. 2 Although the force applied to the button varies slightly, in this embodiment, it is assumed that the force is such that an average adult woman can easily operate the button.

[0028] In the spraying step, the distance L between the nozzle 7a of the hand sprayer 1 and the leaf is set to a predetermined distance or less before the liquid is sprayed. The predetermined distance is, for example, 20 cm or 15 cm. The longer the predetermined distance, the more the liquid is sprayed on the leaf surface per cm. 2 The force exerted by the leaf surface is smaller, while the shorter the distance, the greater the force exerted by the leaf surface. 2Therefore, the predetermined force can be changed by adjusting the amount of liquid sprayed from the nozzle 7a per unit time and the predetermined distance. 2 The liquid may be sprayed over a wider area than 1 cm of the leaf surface. 2 In some cases, the liquid may be sprayed over a narrower area than the area indicated by the arrow 6. Trigger 6 is operated multiple times on the same leaf so that the liquid is sprayed evenly over the entire leaf with the specified force. If the liquid is sprayed over the entire leaf with the specified force by simply operating trigger 6 once, trigger 6 needs to be operated only once per leaf.

[0029] Leaf surface 1cm 2 To measure the force acting on the leaf, a digital force gauge can be used. The digital force gauge has a built-in load cell. After fixing a hard resin plate of a specified area to the input part connected to the load cell, the liquid is sprayed onto the hard resin plate, and the force acting on the leaf surface is measured by 1 cm. 2 By changing the specified distance or the amount of spray per trigger operation, the force on the leaf surface can be measured indirectly. 2 Based on this measurement, it is possible to measure how the force applied to the leaf changes. 2 The predetermined distance and the amount of spray per trigger operation can be determined so that the force received by the leaf is equal to or greater than a predetermined force. 2 The method for measuring the force applied to the object is not limited to the method using a digital force gauge, and other measurement methods may be used.

[0030] If powdery mildew spores are found on the leaves of a plant, 2 By spraying the liquid onto the leaves so that the force exerted by the spray is 0.002 N or more, the spores adhering to the leaves can be washed away. In this case, the method for washing away powdery mildew spores can be carried out by using the liquid and hand spray 1. If the liquid contains an insecticidal or fungicidal component derived from a food ingredient, the insecticidal or fungicidal component derived from the food ingredient can be attached to the leaves.

[0031] The method of washing off powdery mildew spores can be carried out at any time. For example, when the time comes when powdery mildew is likely to develop, and a predetermined time has elapsed since the powdery mildew spores were estimated to have adhered to the leaves of the plant, washing off powdery mildew spores can be carried out by washing off 1 cm of the leaf surface. 2 Powdery mildew spores can be washed away by spraying the liquid onto leaves so that the force exerted on the surface is 0.002 N or greater. It is believed that powdery mildew spores begin to penetrate host cells within several hours of attachment to leaves, and that the haustoria mature after 20 hours. Therefore, it would be expected that spores would be difficult to remove from leaves after one day of attachment. However, it has been surprisingly found that powdery mildew spores can be removed from leaves even 24 hours after attachment by simply applying the liquid to the leaves with the specified force. Thus, in order to achieve the remarkable effect of the present invention, which is to remove spores from leaves even after the haustoria have matured, it is preferable to spray the liquid with the specified force after a specified time has elapsed since the powdery mildew spores attached to the leaves. The specified time is, for example, 24 hours or 30 hours. However, there is no problem with the effectiveness of the method for washing away powdery mildew spores of the present invention if it is performed before the specified time has elapsed since the powdery mildew spores attached to the leaves.

[0032] In the method for washing away powdery mildew spores, the liquid is repeatedly sprayed onto the leaves, for example, once or multiple times within a period of six days or less. Since powdery mildew spores are believed to develop conidia approximately six days after they attach to the leaves, repeated washing at shorter intervals allows the spores to be washed away before they develop conidia, thereby enhancing the effectiveness of preventing powdery mildew from developing. The liquid may be sprayed onto the leaves only once within a period of six days or less, or two or more times within a period of six days or less. The liquid may also be sprayed onto the leaves only once within a period of five days or less, or two or more times within a period of five days or less. The liquid may also be sprayed onto the leaves only once per day.

[0033] (Test example) Next, an example of a plant disease prevention test will be described. The test plant was a cucumber, and powdery mildew spores were applied to cucumber leaves with a brush to prepare for the test. 24 hours after the powdery mildew spores were applied to the leaves, the above liquid was sprayed onto the leaves with a hand sprayer. The condition of the leaves was observed 7 days after spraying. The above liquid was water, but similar test results were obtained even if it contained other ingredients such as sorbitan fatty acid esters. Similar test results were also obtained for plants other than cucumber.

[0034] In each example, spraying was carried out after adjusting the conditions of the distance and spray amount of the hand spray 1 to the leaf surface. 2 The force applied to the object was measured in advance using a digital force gauge. The input part of the digital force gauge was connected to a circular resin plate with a diameter of approximately 4 cm (area of ​​approximately 12.5 cm). 2 ) was connected and measured.

[0035] In Example 1, the digital force gauge measured 0.03 N (1 cm 2 In Example 2, the force applied to the object is 0.04N (1cm). 2 In Example 3, the force applied to the digital force gauge is 0.06 N (1 cm). 2 In Example 4, the force applied to the digital force gauge is 0.10 N (1 cm 2 In Example 5, the force applied to the digital force gauge is 0.15 N (1 cm). 2 Each injection was performed under conditions where the force applied to the nozzle was 0.012 N.

[0036] Comparative Example 1 is an example of no treatment (nothing is sprayed), and Comparative Example 2 is an example of a sample where the measured value of the digital force gauge is 0.010 N (1 cm 2 As a comparative example 3, the digital force gauge measured a force of 0.015N (1cm 2As a comparative example 4, the digital force gauge measured a force of 0.021 N (1 cm 2 The injection was carried out under conditions where the force exerted on the nozzle was 0.0017N.

[0037] In Examples 1 to 5, the diseased area was less than 5% of the leaf, whereas in Comparative Example 1, the diseased area was 50% or more of the leaf, and in Comparative Examples 2 to 4, the diseased area was 25 to less than 50% of the leaf. 2 When the force applied to the liquid is 0.002 N or more, the diseased area is significantly smaller than when it is less than that. The smaller diseased area means that the powdery mildew spores attached to the leaves are washed away by the liquid, and it can be seen that a high disease prevention effect is obtained.

[0038] (Effects of the embodiment) As described above, according to this embodiment, the leaf surface of the plant is 1 cm 2 By spraying the liquid with the hand sprayer 1 so that the force exerted on the surface is 0.002 N or more, the bacteria and spores adhering to the leaves can be washed away. In particular, most of the powdery mildew spores that have been attached to the leaves for 24 hours and whose haustorium has matured can be washed away with the water-based liquid, and this effect is extremely remarkable.

[0039] Furthermore, because this method does not use synthetic fungicides, it is a simple preventative method that can be carried out as many times as necessary along with daily watering, and if necessary, it can also be used in conjunction with spraying insecticides and fungicides, making it extremely effective, especially in home gardening.

[0040] The above-described embodiments are merely examples in all respects and should not be construed as limiting. Furthermore, all modifications and variations within the scope of the claims are within the scope of the present invention. [Industrial Applicability]

[0041] As explained above, this method can be used for, for example, the leaves of various vegetables and ornamental plants. [Explanation of symbols]

[0042] 1 hand spray 2 containers 3 Spray equipment 7a Nozzle

Claims

1. A method for preventing the onset of powdery mildew in plants, characterized by spraying a liquid containing water onto the leaf surfaces of plants with a hand sprayer that sprays an amount of 0.3 ml or more and 1.3 ml or less per trigger operation.

2. The method for preventing powdery mildew on plants according to claim 1, A method for preventing the onset of powdery mildew in plants, comprising spraying the water-containing liquid onto the leaf surfaces of the plants with the hand sprayer from a distance of 20 cm or less from the leaf surfaces.

3. A method for washing away powdery mildew spores, characterized in that a liquid containing water is sprayed onto the leaf surface of a plant using a hand sprayer with a spray volume of 0.3 ml or more and 1.3 ml or less per trigger operation.

4. The method for washing away powdery mildew spores according to claim 3, A method for washing away powdery mildew spores, comprising spraying the water-containing liquid onto the leaf surface of a plant with the hand sprayer from a distance of 20 cm or less from the leaf surface.

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