Methods for preventing mold on fruits

Abstract

An object of the present invention is to provide a method for preventing mold on fruit and a composition for preventing mold on fruit that can improve the antifungal effect on fruit without increasing the amount of antifungal agent used or changing the composition. A method for preventing mold on fruit, comprising applying a fungicide and nanobubble water to a plant body that bears fruit.

Description

[Technical field]

[0001] The present invention relates to a method for preventing mold on fruits. By law Regarding. [Background technology]

[0002] Fruits that develop mold during growth or after harvest are often discarded because they cannot be shipped due to quality deterioration such as rotting or deterioration, resulting in a decrease in the number of shipments (yield). In particular, for fruits that are stored in warehouses for a certain period of time after harvest for shipping adjustment or ripening, mold often germinates in some of the fruits over the course of storage time, and grows and spreads, eventually causing rotting or deterioration.

[0003] Since the occurrence of mold causes great social and economic losses, it is extremely important to prevent the occurrence of mold in fruits. Meanwhile, in general anti-mold methods, anti-mold agents are often applied to fruits before or after harvest.

[0004] In light of the above concerns, various antifungal agents have been developed to date, and to give one example, Patent Document 1 describes "a spoilage prevention composition for fruits and vegetables, characterized by containing capillin and polyphenols" and a method for using the same (see "Claim 1" of Patent Document 1 and "Examples" in the specification). The spoilage prevention composition for fruits and vegetables described in Patent Document 1 can inhibit the occurrence and proliferation of mold and inhibit spoilage of fruits and vegetables, and as a result, it becomes possible to prevent a decrease in the commercial value of fruits and vegetables. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2006-042799 A Summary of the Invention [Problem to be solved by the invention]

[0006] Regarding the use of antifungal agents, when food safety is taken into consideration, it becomes difficult to increase the amount of antifungal agent used (amount sprayed) per unit yield, but if the amount used is reduced, there is a possibility that sufficient antifungal effect will not be obtained. In addition, in Patent Document 1, additives such as surfactants and fatty acid glycerides are further added to the spoilage prevention agent for fruits and vegetables in order to improve the antifungal effect. On the other hand, there is a demand for improving the antifungal effect without increasing the amount of antifungal agent used or changing the composition (specifically, adding additives).

[0007] Therefore, an objective of the present invention is to provide an antifungal method for fruits and an antifungal composition for fruits that can improve the antifungal effect on fruits without increasing the amount of antifungal agent used or changing the composition. [Means for solving the problem]

[0008] As a result of intensive research aimed at achieving the above-mentioned object, the present inventors discovered that the application of an antifungal agent and nanobubble water improves the antifungal effect on fruits without increasing the amount of the antifungal agent used or changing its composition, and thus completed the present invention. That is, the present inventors have found that the above object can be achieved by the following configuration.

[0009] [1] A method for preventing mold on fruit, comprising applying a fungicide and nanobubble water to a fruit-bearing plant. [2] The method for preventing mold on fruits described in [1], comprising spraying the antifungal agent diluted with the nanobubble water onto the plant body. [3] The method for preventing mold on fruit described in [1] or [2], wherein the most frequent particle size of the bubbles contained in the nanobubble water is 10 to 500 nm. [4] The method for preventing mold on fruit described in any one of [1] to [3], wherein the bubbles contained in the nanobubble water contain at least one gas selected from the group consisting of oxygen, nitrogen, ozone, and carbon dioxide. [5] The above nanobubble water has a density of 1×10 8pieces / mL~1×10 10 The method for preventing mold on fruit according to any one of [1] to [4], wherein the fruit has air bubbles of 10 bubbles / mL. [6] The method for preventing mold on fruit described in any one of [1] to [5], wherein the fruit is ripened by being stored in a warehouse after harvest. [7] The method for preventing mold on fruit described in [6], wherein the fruit is a mandarin orange. [8] A composition for preventing mold on fruits, comprising nanobubble water and an antifungal agent. Effect of the Invention

[0010] According to the present invention, it is possible to provide an antifungal method and an antifungal composition for fruit that can improve the antifungal effect on fruit without increasing the amount of antifungal agent used or changing the composition. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic diagram showing an example of a nanobubble generator. [Diagram 2] This is an image of mandarin oranges harvested in experimental area I. [Diagram 3] This is an image of mandarin oranges harvested in experimental area II, and an enlarged image (bottom right) of a mandarin orange with blue mold. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The present invention will be described in detail below. The following description of the components may be based on representative embodiments of the present invention, but the present invention is not limited to such embodiments. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits.

[0013] [Methods for preventing mold on fruit] The method for preventing mold on fruits of the present invention is a method for preventing mold on fruits, which comprises applying an antifungal agent and nanobubble water to a plant body on which the fruit grows. Here, the term "fruit-bearing plants" refers to trees (fruit trees) and grasses that bear fruit. The fruits may be edible or ornamental.

[0014] Furthermore, the occurrence and proliferation of molds which are inhibited by the present invention are molds which occur on fruits, specifically, for example, molds which occur due to blue mold pathogens such as Penicillium italicum, Penicillium digitaum, and Penicillium expansum; and molds which occur due to Botrytis cinerea.

[0015] An "antifungal agent" is a chemical agent for preventing or removing at least one of the occurrence and proliferation of mold, and is also called a mildewproofing agent (mold inhibitor), and is applied in a diluted or dissolved state (i.e., in liquid form). The antifungal agent may be one that exerts its efficacy by being attached to at least a part of the leaves, stems, and fruits of a plant, or one that exerts its efficacy by being absorbed by the plant through its roots after being sown in a medium such as soil. In addition, examples of antifungal agents include thiophanate methyl agent, iminothaczine acetate, benomyl agent, Topsin M wettable powder, Beftopsin flowable, Befran liquid 25, and benzimidal agent, Benlate wettable powder, which are effective against blue mold disease; Examples of effective agents against gray mold include Topsin M hydrate, Benlate hydrate, Sumirex hydrate, Robral hydrate, Getter hydrate, Sumiblend hydrate, Polyoxin AL emulsion, Polybelin hydrate, Diametrist DF, Belcut hydrate, Sabia flowable 20, Fulpica flowable, Scala flowable, Amistar 20 flowable, Strobe Dry flowable, Password hydrated granule, Just Meet hydrated granule, Dimazine, Triazine hydrate 50, Botkiller hydrate, Ecoshot, Botopica hydrate, and Qantas Dry flowable, as well as the organochlorine agent Daconil 1000.

[0016] Although antifungal agents are primarily used for the purpose of suppressing the occurrence and proliferation of mold on fruit after harvest, they may also be used for the purpose of suppressing the occurrence and proliferation of mold on fruit during the growth process before harvest (particularly, during the period from fruit set to harvest).

[0017] The "nanobubble water" used in the fruit antifungal method of the present invention is water containing bubbles with a diameter of less than 1 μm, more precisely, water with nanobubbles mixed in. In addition, with regard to "water with nanobubbles mixed in," water used to generate nanobubble water (raw water for nanobubble water, for example, well water containing impurities) that unavoidably contains nanobubbles due to its properties, etc., is excluded from the above-mentioned "water with nanobubbles mixed in." The diameter (particle size) of the bubbles contained in the nanobubble water, as well as the mode particle size and number of bubbles described below, are values ​​obtained by measuring the Brownian motion movement speed of bubbles in water using a nanoparticle tracking analysis method. In this specification, values ​​measured using a nanoparticle analysis system, NanoSight Series (manufactured by NanoSight, Inc.) are used. In addition, with the NanoSight series nanoparticle analysis system (manufactured by NanoSight), the diameter (particle size) can be calculated from the speed of the Brownian motion of the particle measured, and the most frequent particle size can be confirmed as the mode diameter from the particle size distribution of the nanoparticles present.

[0018] According to the method for preventing mold growth on fruits of the present invention, as described above, by applying an antifungal agent and nanobubble water to a plant body on which fruits grow, the antifungal effect on the fruits is improved without increasing the amount of the antifungal agent used or changing its composition.

[0019] In the present invention, from the viewpoint of further improving the antifungal effect, the mode particle size of the bubbles contained in the nanobubble water is preferably 10 to 500 nm, more preferably 30 to 300 nm, and particularly preferably 70 to 130 nm.

[0020] The gas that constitutes the bubbles contained in the nanobubble water is not particularly limited, but from the viewpoint of allowing the bubbles to remain in the water for a long period of time, gases other than hydrogen are preferred. Specific examples of the gas that can be used include air, oxygen, nitrogen, fluorine, carbon dioxide, and ozone. Of these, from the viewpoint of further improving the antifungal effect, it is preferable to contain at least one gas selected from the group consisting of oxygen, nitrogen, ozone and carbon dioxide, and in particular, it is more preferable to contain at least one of oxygen and ozone, because this allows the bubbles to remain for a longer period of time. Here, containing at least one of oxygen and ozone means that the gas is contained at a concentration higher than the concentration in air. The same applies to nitrogen and carbon dioxide. The oxygen concentration in the bubbles is preferably 30% by volume or more, and more preferably more than 50% by volume and 100% by volume or less. The ozone concentration is preferably 0.5 ppm or more, and more preferably 1 ppm or more.

[0021] The nanobubble water is 1×10 8 pieces / mL~1×10 10 It is preferable that the solution has 1×10 bubbles / mL. In particular, it is preferable that the solution has 1×10 bubbles / mL because this provides a good balance between the bubble generation time and the bubble persistence. 8 More than 1×10 10 More preferably, the number of bubbles is less than 5×10 8 pieces / mL~5×109 It is even more preferable that the solution has bubbles per mL.

[0022] The nanobubble water may contain components other than water and air bubbles. Examples of the other components include fertilizers and pesticides (excluding fungicides), etc. The types and contents of other components in the nanobubble water are not particularly limited and can be selected according to the purpose. However, in the present invention, it is preferable that the nanobubble water does not substantially contain radicals as the other components. With regard to "substantially free of radicals," in addition, the water "substantially free of radicals" will be considered to be "substantially free of radicals" if radicals are unavoidably contained due to the water used to generate the nanobubble water (for example, well water containing impurities). On the other hand, the water will not be considered to be "substantially free of radicals" if radicals generated by some kind of artificial operation are mixed in.

[0023] Examples of methods for generating the nanobubble water include a static mixer method, a Venturi method, a cavitation method, a steam condensation method, an ultrasonic method, a swirling flow method, a pressurized dissolution method, and a micropore method. Here, the antifungal method for fruits of the present invention may have a generating step of generating the nanobubble water before applying the nanobubble water. That is, the antifungal method for fruits of the present invention may be an antifungal method having a generating step of taking water from a water source such as a water storage tank, a well, or agricultural water into a nanobubble generator to generate nanobubble water, and an application step of applying the generated nanobubble water and an antifungal agent. Examples of a method for taking water from a water source into the nanobubble generator include a method for pumping water from the water source using a bucket or a pump, and a method for connecting a flow path laid between the water source and the nanobubble generator to the nanobubble generator and directly feeding water from the flow path to the nanobubble generator.

[0024] In addition, as the apparatus for generating the nanobubble water, a generation method using an apparatus that does not intentionally generate radicals is preferable, and specifically, for example, a method of generating the nanobubble water using the nanobubble generating apparatus described in paragraphs

[0080] to

[0100] of JP2018-15715A can be mentioned. The contents of the above are incorporated herein by reference.

[0025] Another example of a nanobubble generator that does not intentionally generate radicals is a microbubble generator having a liquid dispenser that dispenses water, a gas mixer that pressurizes and mixes gas into the water dispensed from the liquid dispenser, and a microbubble generator that generates microbubbles in the water by passing the water mixed with gas through the inside, in which the gas mixer pressurizes and mixes gas into the liquid that flows in a pressurized state toward the microbubble generator between the liquid dispenser and the microbubble generator. A specific example is the nanobubble generator shown in Fig. 1. The nanobubble generator 10 shown in FIG. 1 includes therein a liquid dispenser 30, a gas mixer 40, and a nanobubble generating nozzle 50. The liquid dispenser 30 is composed of a pump, and takes in and dispenses raw water (e.g., well water) for nanobubble water. The gas mixer 40 has a container 41 in which compressed gas is sealed, and a substantially cylindrical gas mixer body 42, and introduces the compressed gas in the container 41 into the gas mixer body 42 while allowing the water dispensed from the liquid dispenser 30 to flow into the gas mixer body 42. As a result, gas-mixed water is generated in the gas mixer body 42. The nanobubble generating nozzle 50 generates nanobubbles in the gas-mixed water according to the principle of pressurized dissolution by passing the gas-mixed water through the inside of the nanobubble generating nozzle 50, and the same structure as that of the nanobubble generating nozzle described in JP 2018-15715 A can be adopted as the structure thereof. The nanobubble water generated in the nanobubble generating nozzle 50 is sprayed from the tip of the nanobubble generating nozzle 50, and then flows out of the nanobubble generator 10 and is delivered to a predetermined destination through a flow path (not shown). As described above, in the nanobubble generator 10, the gas mixer 40 mixes compressed gas into water (raw water) that flows in a pressurized state toward the nanobubble generating nozzle 50 between the liquid dispenser 30 and the nanobubble generating nozzle 50. This makes it possible to avoid problems such as cavitation that occur when gas is mixed into water on the suction side (suction side) of the liquid dispenser 30. In addition, since the gas is mixed into the water in a pressurized (compressed) state, the gas can be mixed against the water pressure at the gas mixing point. For this reason, it becomes possible to appropriately mix the gas into the water without generating a negative pressure at the gas mixing point. Furthermore, it is preferable that a flow path for water supplied from a water source such as a well or a water supply is connected to the suction side of the liquid dispenser 30, and the pressure of the water flowing from the upstream side of the liquid dispenser 30 to the liquid dispenser 30 in the flow path (i.e., the water pressure on the suction side) is positive. In this case, the above configuration becomes more meaningful. That is, when the water pressure (suction pressure) on the upstream side of the liquid dispenser 30 becomes positive, gas is mixed into the water on the downstream side of the liquid dispenser 30, so the configuration of the nanobubble generator 10 that can appropriately mix gas into the water even on the downstream side of the liquid dispenser 30 becomes more prominent.

[0026] The water (raw water) used to generate the nanobubble water is not particularly limited, and examples of water that can be used include surface water such as rainwater, tap water, well water, and river water, agricultural water, pure water, ultrapure water, and distilled water. Such water may be subjected to other treatments before being used to generate nanobubble water. Examples of other treatments include pH adjustment, precipitation, filtration, and sterilization (disinfection). Specifically, for example, when agricultural water is used, the agricultural water may typically be used after being subjected to at least one of precipitation and filtration.

[0027] In the present invention, the application mode of the antifungal agent and the nanobubble water is not particularly limited since it differs depending on the cultivation method of the plant body. Examples of the application mode during the growth of the plant body include spraying in soil cultivation, mixing into the culture solution used in nutrient solution cultivation (hydroponics, spray cultivation, or solid medium cultivation), and spraying (irrigation) in nutrient solution soil cultivation (irrigation and simultaneous fertilization cultivation). Regarding application in soil cultivation, the antifungal agent and the nanobubble water may be applied directly to the plant body, or may be sown in a medium such as soil and absorbed by the plant body from the medium. Furthermore, examples of the manner in which the antifungal agent and the nanobubble water are sprayed onto a plant body include a manner in which the antifungal agent diluted with the nanobubble water is sprayed onto the plant body, and a manner in which the antifungal agent and the nanobubble water are sprayed onto the plant body separately at different times. Among these, it is more preferable to spray the antifungal agent diluted with the nanobubble water onto a plant body, because the operation is simple and the antifungal effect is further improved. The method of application is not particularly limited, and any method may be used, such as spraying by a sprayer or the like, scattering or dripping from above the plant body, or spraying by applying pressure from the nozzle of a sprinkler.

[0028] In the present invention, the timing of application of the antifungal agent and the nanobubble water is not particularly limited since it varies depending on the type of antifungal agent and the type of fruit, but for example, it is preferable to apply them during part or all of the period from sowing to harvesting, and more preferably one to several months before harvesting. If a large amount of rain falls after application of the antifungal agent, it is recommended to apply the antifungal agent and the nanobubble water again after the rain stops.

[0029] In the present invention, the plant body to which the above-mentioned antifungal agent and the above-mentioned nanobubble water are applied is not particularly limited as long as it is a plant body that bears fruits on which mold may develop, and examples thereof include plants that bear fruits on which blue mold may develop and plants that bear fruits on which gray mold may develop. Specifically, for example, fruit trees such as citrus plants (e.g., mandarin orange, kumquat, trifoliate orange, bitter orange, pomelo, lemon, lime, yuzu, orange, grapefruit, etc.), grape family plants (e.g., grapes, etc.), rose family plants (e.g., apple, pear, European pear, cherry, peach, plum, plum, loquat, etc.), ebony family plants (e.g., persimmon, etc.), Musaceae family plants (e.g., banana, etc.), Lauraceae family plants (e.g., avocado, etc.), Bromeliaceae family plants (e.g., pineapple, etc.), Carapaaceae plants (e.g., papaya, etc.), Anacardiaceae plants (e.g., mango, etc.), Actinidiaceae plants (e.g., kiwi fruit, etc.), and Mulberry family plants (e.g., fig, etc.); Fruit vegetables such as Cucurbitaceae plants (e.g., gourds, melons, watermelons, and cucumbers), Solanaceae plants (e.g., eggplants, tomatoes (including cherry tomatoes), and bell peppers), and Rosaceae plants (e.g., strawberries); etc. Among these, plants that produce fruits that ripen when stored in a warehouse after harvest (e.g., fruit trees of the Rutaceae family, persimmons, European pears, kiwi fruit, bananas, papayas, mangoes, peaches, etc.) are more preferred. The above fruits are usually stored in a densely packed state in a warehouse, so if mold occurs in some individuals, the mold is likely to spread to other individuals. In such a situation, the fruit anti-mold method of the present invention, which can improve the anti-mold effect on fruits, becomes more meaningful. Among the plants that bear fruits that ripen when stored in a warehouse after harvest, Rutaceae plants are more preferred, with mandarin oranges being even more preferred.

[0030] [Anti-fungal composition for fruits] The antifungal composition for fruits of the present invention (hereinafter also simply referred to as "the composition of the present invention") is a composition containing nanobubble water and an antifungal agent. Here, the nanobubble water and the antifungal agent are the same as the nanobubble water and the antifungal agent described in the above-mentioned method for preventing mold on fruit of the present invention. The composition of the present invention may also contain other ingredients explained in the above-mentioned method for preventing mold on fruit of the present invention.

[0031] The composition of the present invention preferably contains the above-mentioned nanobubble water as a base material. Here, the "base material" refers to a component that is contained in the composition at more than 50% by mass of the total mass of the liquid content (components other than solid content) contained in the composition, and is preferably contained at 70% by mass or more of the liquid content, more preferably at 90% by mass or more, and even more preferably at 99% by mass or more. In addition, in the composition of the present invention, the content of the antifungal agent is not particularly limited, but is preferably 0.00001 to 10 parts by mass, and more preferably 0.00005 to 5 parts by mass, relative to 100 parts by mass of the nanobubble water. EXAMPLES

[0032] The present invention will be described in more detail below with reference to examples. The materials, amounts, ratios, processing contents, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be interpreted as being limited by the following examples.

[0033] <Exam Content> The test was conducted on mandarin oranges grown in Minamiashigara City, Kanagawa Prefecture. Specifically, mandarin oranges (variety: Aoshima) were grown in the following test plots I and II from April to December 2017, and the fruits were harvested in December of the same year and then stored in a warehouse for approximately two months to ripen. Test plots I and II were set up in two different, adjacent fields. Test area I: Antifungal agents (Topsin M and Omite hydrate) were diluted 2000 times with nanobubble water and sprayed on mandarin orange fruits before harvest (November 2017). Test area II: Before harvest (November 2017), antifungal agents (Topsin M and Omite hydrate) were diluted 2000 times with ordinary tap water and sprayed on mandarin orange fruits. Seven mandarin trees were planted in each experimental plot. The amount of antifungal agent to be applied, its concentration after dilution, and the spraying procedure were set according to standard methods and adjusted so that they were roughly the same in both test plots. Specifically, the antifungal agent was diluted to a specified concentration and sprayed over the entire fruit tree at a spray volume of 10 to 15 L per tangerine tree. In addition, the mandarin orange fruits harvested in each test area were stored in the same warehouse, and were packed into collection containers according to test area and stored.

[0034] <How to generate nanobubble water> Nanobubble water was produced by generating bubbles (nanobubbles) in water using a pressurized dissolution method using a nanobubble generator (manufactured by Kakuichi Manufacturing Co., Ltd., Aqua Solution Division (now Aqua Solution Co., Ltd.), 100V, 10L / min type). The water (raw water) used to generate the nanobubble water was tap water, and the type of gas that constituted the bubbles was oxygen (industrial oxygen, concentration: 99.5% by volume). The conditions for generating nanobubbles using the above nanobubble generator were as follows: Number of bubbles per mL of water: 5 x 10 8 pieces / mL Bubble size (modal particle diameter): 100 nm

[0035] <Evaluation of anti-mold effect> For each test area, 1,000 randomly selected mandarin fruits were used as samples and visually inspected for the presence or absence of blue mold one month and two months after the start of storage (January and February 2018). They were then evaluated using the following three-level criteria. A: No blue mold was found in any of the 1,000 pieces. B: Of 1,000 fruits, blue mold was confirmed to have developed in only 1 to 3 fruits. C: Blue mold was confirmed in 4 or more fruits out of 1,000. The evaluation results are shown below. Test area I:A (see Figure 2). Test area II: C (see Figure 3). These results demonstrate the effectiveness of nanobubble water in preventing mold on fruit. [Explanation of symbols]

[0036] 10 Nanobubble generator 30 Liquid dispensing machine 40 Gas mixing machine 41 Container 42 Gas mixing machine body 50 Nanobubble generating nozzle

Claims

1. A method for preventing mold growth on fruit, comprising applying an antifungal agent and nanobubble water generated using tap water as raw water to the fruit before harvesting during the growth period of the fruit-bearing plant body, thereby suppressing the growth of mold on the fruit after harvesting.

2. The method for preventing mold on fruits according to claim 1 , further comprising spraying the antifungal agent diluted with the nanobubble water onto the plant body.

3. The method for preventing mold on fruits according to claim 1 or 2, wherein the most frequent particle size of bubbles contained in the nanobubble water is 10 to 500 nm.

4. The method for preventing mold growth on fruits according to any one of claims 1 to 3, wherein the bubbles contained in the nanobubble water contain at least one gas selected from the group consisting of oxygen, nitrogen, ozone, and carbon dioxide.

5. The nanobubble water is 1×10 ８ pieces / mL ~ 1×10 １０ The method for preventing mold on fruits according to any one of claims 1 to 4, wherein the fruit has air bubbles of 10 bubbles / mL.

6. The method for preventing mold on fruit according to any one of claims 1 to 5, wherein the fruit is ripened by being stored in a warehouse after harvest.

7. The method for preventing mold on fruit according to claim 6, wherein the fruit is a mandarin orange fruit.

Images