Fruit vegetable plant cultivation method, tomato, culture solution for fruit vegetable plant hydroponics, and fruit vegetable plant hydroponics device

Abstract

The present invention pertains to: a fruit vegetable plant cultivation method that involves culturing a fruit vegetable plant through hydroponics using a culture solution having an Si content of 60 mass ppm or more; a tomato; a culture solution for fruit vegetable plant hydroponics; and a fruit vegetable plant hydroponics device.

Description

Method for cultivating fruit and vegetable plants, culture solution for hydroponic cultivation of tomatoes and fruit and vegetable plants, and hydroponic cultivation device for fruit and vegetable plants

[0001] The present disclosure relates to a method for cultivating fruit and vegetable plants, a culture solution for hydroponic cultivation of tomatoes and fruit and vegetable plants, and an apparatus for hydroponic cultivation of fruit and vegetable plants.

[0002] Hydroponic cultivation is known as a method for cultivating fruit and vegetable plants such as tomatoes. In recent years, in order to increase the sugar content of harvested products, a culture solution containing sodium chloride or the like (e.g., seawater) has been used in hydroponic cultivation. For example, Japanese Patent Laid-Open Publication No. 2004-357638 discloses the use of a culture solution prepared by diluting seawater having a nitrate nitrogen content of 0.27 mg / L or more, a silicic acid content of 3.2 mg / L or more, a coliform count of less than 1.8 MPN / 100 ml, and a general bacterial count of less than 1 / ml or less for the hydroponic cultivation of tomatoes. Japanese Patent No. 6,535,421 also discloses the use of seawater as a culture solution for the hydroponic cultivation of tomatoes.

[0003] It has been known that when the concentration of salts such as sodium chloride in the raw water of the culture solution used in hydroponic cultivation is high, the salt concentration of the culture solution becomes higher than the appropriate range, resulting in a decrease in yield. Therefore, there is a demand for improving the yield.

[0004] The problem that one embodiment of the present disclosure aims to solve is to provide a method for cultivating fruit and vegetable plants, a culture solution for hydroponic cultivation of tomatoes and fruit and vegetable plants, and a hydroponic cultivation device for fruit and vegetable plants, which are capable of achieving high yields even when the solution contains salts such as sodium chloride.

[0005] Means for solving the above problems include the following aspects. <1> A method for cultivating fruit and vegetable plants by hydroponics using a culture solution having a Si content of 60 ppm by mass or more. <2> The method for cultivating fruit and vegetable plants according to the above <1>, wherein the culture solution contains silicate. <3> The method for cultivating fruit and vegetable plants according to the above <1> or <2>, wherein the culture solution contains sodium chloride. <4> The method for cultivating fruit and vegetable plants according to any one of the above <1> to <3>, wherein the culture solution has an electrical conductivity of 4.0 ds / m or more. <5> The method for cultivating fruit and vegetable plants according to any one of the above <1> to <4>, wherein the hydroponic cultivation of the fruit and vegetable plants is carried out at least after planting of fruit and vegetable seedlings. <6> A method for cultivating fruit and vegetable plants according to the above <1> to <4>, wherein the culture solution is irradiated with light at a light intensity of 200 μmol / m ２ / s~800μmol / m ２ <7> The method for cultivating fruit and vegetable plants according to <6> above, comprising irradiating the fruit and vegetable seedlings with artificial light of 10 ... <12> The culture solution for hydroponic cultivation of fruit and vegetable plants according to <11> above, having an electrical conductivity of 4.0 ds / m or more. <13> A fruit and vegetable hydroponic cultivation device comprising a culture solution tank containing the culture solution for hydroponic cultivation of fruit and vegetable plants according to <11> or <12> above.

[0006] According to one embodiment of the present disclosure, it is possible to provide a method for cultivating fruit and vegetable plants, a culture solution for hydroponic cultivation of tomatoes and fruit and vegetable plants, and a hydroponic cultivation device for fruit and vegetable plants, which are capable of achieving high yields even when salts such as sodium chloride are contained.

[0007] Fig. 1 is a schematic cross-sectional view showing an embodiment of a hydroponic cultivation apparatus used in a seedling raising process. Fig. 2 is a schematic cross-sectional view showing an embodiment of a hydroponic cultivation apparatus for fruit and vegetable plants according to the present disclosure.

[0008] Modes for carrying out the present disclosure are described in detail below. However, the present disclosure is not limited to the following embodiments. In the following embodiments, components (including element steps, etc.) are not essential unless otherwise specified. The same applies to numerical values ​​and their ranges, and do not limit the present disclosure. In this disclosure, numerical ranges indicated using "to" include the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In numerical ranges described in stages in this disclosure, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. Furthermore, in numerical ranges described in this disclosure, the upper or lower limit of that numerical range may be replaced with a value shown in the examples. In this disclosure, "mass" and "weight" are synonymous. In this disclosure, the term "process" includes not only independent processes, but also processes that cannot be clearly distinguished from other processes as long as the intended purpose of the process is achieved. In this disclosure, "fruit vegetable plant" refers to a plant that produces fruit. In the present disclosure, the term "culture solution" refers to a solution in which nutrients (e.g., inorganic substances, organic substances) necessary for plant growth are dissolved in water or the like.

[0009] [Method for Cultivating Fruit and Vegetable Plants] In the method for cultivating fruit and vegetable plants according to the present disclosure, fruit and vegetable plants are cultivated by hydroponics using a culture solution having a Si content of 60 ppm by mass or more (hereinafter also referred to as a "specific culture solution"). Cultivation using the specific culture solution is preferably carried out in a cultivation step after a seedling raising step, and may be started either before or after planting the fruit and vegetable plants after seedling raising, and is preferably started after planting the fruit and vegetable plants.

[0010] The inventors have discovered that, although the reason is unclear, by setting the Si content of the culture solution used in hydroponic cultivation to 60 ppm by mass or more, high yields can be achieved even when salts such as sodium chloride are added. Although the dilution ratio of the culture solution disclosed in JP 2004-357638 A is not specified, if seawater is diluted 10 times, which is a common dilution ratio, the Si content is approximately 0.089 ppm by mass, making it difficult to improve the yield. Furthermore, the culture solution disclosed in JP 6535421 A is seawater, but the Si content is approximately 0.89 ppm by mass, making it difficult to improve the yield.

[0011] The hydroponic method is not particularly limited, and examples thereof include flooded hydroponic method, thin film hydroponic method, spray hydroponic method, and drip hydroponic method in which liquid fertilizer is dripped onto the roots or root supports.

[0012] The nutrient solution can be prepared to achieve the desired fertilizer composition by appropriately selecting and blending single fertilizers. The fertilizer composition of the nutrient solution can be adjusted using a blending program such as "Best Blend" provided by the NPO Japan Hydroponic Culture Research Association. The component composition of the nutrient solution can be adjusted to have the desired component content by properly blending single fertilizers. The components in the nutrient solution can be quantified using ion chromatography or high-frequency inductively coupled plasma (ICP) analysis.

[0013] Examples of fertilizer components in liquid fertilizers include sodium nitrate, calcium chloride, magnesium chloride, ammonium chloride, potassium sulfate, and potassium dihydrogen phosphate. Liquid fertilizers may be simple fertilizers containing a single fertilizer component as the main component, compound fertilizers containing two or more of nitrogen (N), phosphorus (P), and potassium (K), or compound fertilizers containing a combination of multiple solid fertilizers. The required amount of Si component can also be added to the compound fertilizer.

[0014] Fruit vegetable plants include, but are not limited to, solanaceae plants such as tomatoes, eggplants, and bell peppers; cucurbitaceae plants such as melons, cucumbers, pumpkins, and zucchini; legumes such as kidney beans, peas, and broad beans; roseaceae plants such as strawberries; mallows such as okra; and grasses such as corn. Among the above-mentioned fruit vegetable plants, solanaceae plants or cucurbitaceae plants are suitable for the cultivation method of the present disclosure, with tomatoes or melons being more suitable. Tomatoes include midi tomatoes, cherry tomatoes, and fruit tomatoes. Melons include netted melons such as green-fleshed and red-fleshed varieties, as well as netless melons.

[0015] The lower limit of the Si content in the specific culture solution may be 70 mass ppm or more, or may be 80 mass ppm or more. From the viewpoint of uniformity of the culture solution, the upper limit of the Si content in the specific culture solution is preferably 300 mass ppm or less, more preferably 200 mass ppm or less, and even more preferably 100 mass ppm or less. In the present disclosure, the Si content in the culture solution refers to the Si content relative to the total mass of the culture solution. In the present disclosure, the Si content in the culture solution is measured using an ICP-OES (inductively coupled plasma optical emission spectrometer). The Si content of the culture solution can be adjusted, for example, by adding sodium silicate or the like to the culture solution.

[0016] From the viewpoint of improving yield, the specific culture solution preferably contains a silicate. From the viewpoint of improving yield, the silicate is preferably sodium silicate. The content of sodium silicate relative to the total mass of the specific culture solution is not particularly limited as long as the Si content is 60 mass ppm or more. If the pH becomes higher than the preferred range as a result of adding the target amount of sodium silicate, it is preferable to adjust the pH using dilute hydrochloric acid or the like.

[0017] From the viewpoint of increasing the sugar content, the specific culture solution preferably contains sodium chloride. From the viewpoint of increasing the sugar content, it is preferable to add sodium chloride to the culture solution in an amount such that the electrical conductivity of the specific culture solution is 4.0 ds / m or more, more preferably 4.5 ds / m or more, and even more preferably 6.0 ds / m or more. From the viewpoint of improving yield, the upper limit of the electrical conductivity of the specific culture solution is preferably 20.0 ds / m or less, more preferably 10.0 ds / m or less, and even more preferably 8.0 ds / m or less. In the present disclosure, the electrical conductivity of the culture solution is measured in the culture solution at 25°C using an electrical conductivity meter (e.g., HI98131 manufactured by Hannai Instruments).

[0018] The dissolved oxygen concentration of the specific culture solution is preferably 3.5 mg / L or higher, more preferably 4.5 mg / L or higher, and even more preferably 6.0 mg / L or higher. There is no upper limit to the dissolved oxygen concentration of the specific culture solution; the higher the concentration, the better. It is preferable to set the dissolved oxygen concentration at the saturation concentration at the temperature of the culture solution being used. For example, the saturated dissolved oxygen concentration of distilled water at 27°C under 1 atmosphere is 7.87 mg / L. In the present disclosure, the dissolved oxygen concentration of the culture solution is measured in the culture solution at 27°C using an oxygen concentration monitor (e.g., Seven2GoPro manufactured by Mettler Toledo). The oxygen concentration monitor can be placed in the culture solution tank where the culture solution is stored and used. The dissolved oxygen concentration of the culture solution can be adjusted by using an oxygen supply mechanism, adjusting the circulation rate of the culture solution, etc.

[0019] The pH of the specific culture solution is preferably 3.5 to 8.0, and more preferably 4.5 to 7.0. The pH of the culture solution is measured using a pH monitor (e.g., HI98131 manufactured by Hanna Instruments) in the nutrient solution at 27°C. The pH of the culture solution can be adjusted, for example, by adding hydrochloric acid, sodium hydroxide, etc. to the culture solution.

[0020] Cultivation of fruit and vegetable plants by hydroponic methods using a specific culture solution may be carried out either before or after planting of the fruit and vegetable seedlings, or before and after planting of the fruit and vegetable seedlings, from the viewpoint of improving yield and achieving high sugar content, and is preferably carried out at least after planting of the fruit and vegetable seedlings. The cultivation process will be described later. Furthermore, from the viewpoint of achieving high sugar content, cultivation of fruit and vegetable plants by hydroponic methods using a specific culture solution is preferably carried out after planting of the fruit and vegetable seedlings and after flowering of the second fruit cluster stage. In the process of cultivating germinated fruit and vegetable plants into fruit and vegetable seedlings (seedling raising process), from the viewpoint of cultivation efficiency, it is preferable to use a culture solution other than the specific culture solution, i.e., a culture solution with a Si content of less than 60 ppm by mass, more preferably a culture solution with a Si content of less than 30 ppm by mass, and even more preferably a culture solution with a Si content of less than 3 ppm by mass.

[0021] - Cultivation step - The method for cultivating fruit and vegetable plants of the present disclosure may include a cultivation step. In the cultivation step, fruit and vegetable plant seedlings are planted and cultivated. From the viewpoint of improving yield and achieving high sugar content, it is preferable that the fruit and vegetable plants be cultivated by a hydroponic method using a specific culture solution after at least flowering of the second fruit cluster stage.

[0022] During the cultivation process, temperature conditions can be adjusted by irradiating artificial light onto the fruit and vegetable plant seedlings. For example, temperature conditions can be adjusted to two or more types: light temperature and dark temperature. From the viewpoints of cultivation efficiency, high sugar content, etc., the upper limit of the light temperature is preferably 29°C or lower, more preferably 28.5°C or lower, and even more preferably 28°C or lower. From the viewpoints of cultivation efficiency, high sugar content, etc., the lower limit of the light temperature is preferably 15°C or higher, more preferably 20°C or higher, and even more preferably 25°C or higher. From the viewpoints of cultivation efficiency, high sugar content, etc., the upper limit of the dark temperature is preferably 25°C or lower, more preferably 23°C or lower, and even more preferably 22°C or lower. From the viewpoints of cultivation efficiency, high sugar content, etc., the lower limit of the dark temperature is preferably 10°C or higher, more preferably 13°C or higher, and even more preferably 15°C or higher. The light temperature and dark temperature are measured by placing a thermometer 1 cm away from the fruit and vegetable plants. As the thermometer, for example, a temperature and humidity sensor THA-3151 manufactured by T&D Co., Ltd. can be used. In this disclosure, the "light period" refers to a period during which fruit and vegetable plants are irradiated with light from a light source. In this disclosure, the "dark period" refers to a period during which fruit and vegetable plants are not irradiated with light from a light source. The method for controlling the light period temperature and the dark period temperature is not particularly limited, and can be carried out by a conventionally known method. For example, the light period temperature and the dark period temperature can be controlled by monitoring the light period temperature and the dark period temperature of the seedling environment using the above-mentioned thermometer and blowing hot or cold air as necessary.

[0023] From the viewpoint of cultivation efficiency, high sugar content, etc., the ratio of light period time to dark period time (light period time / dark period time) is preferably 0.3 to 3, and more preferably 0.5 to 2.

[0024] The light source for the artificial light is not particularly limited, and examples include semiconductor light sources such as LEDs (light-emitting diodes) and discharge lamps such as fluorescent lamps. However, in the method for cultivating fruit and vegetable plants according to the present disclosure, it is preferable to use LEDs. One type of LED may be used, or two or more types may be used. The LED may emit visible light such as red, blue, or yellow, or may emit invisible light such as ultraviolet light (wavelength 380 nm or less) or infrared light (wavelength 780 nm or more). However, from the viewpoint of promoting photosynthesis in the first tomato plant, LEDs that emit light in the wavelength range of 400 nm to 700 nm are preferred.

[0025] From the viewpoints of cultivation efficiency, high sugar content, etc., the relative humidity during the cultivation process is preferably controlled to 50% to 80%, and more preferably 55% to 77%. The relative humidity is measured by placing a hygrometer 1 cm away from the fruit vegetable plants. As a hygrometer, for example, a temperature and humidity sensor THA-3151 manufactured by T&D Co., Ltd. can be used. The method for controlling humidity is not particularly limited, and can be carried out by a conventionally known method. For example, humidity conditions can be controlled by monitoring the humidity of the seedling environment using the hygrometer and, as necessary, using an air conditioner with a humidifying function and a dehumidifying function.

[0026] From the viewpoint of cultivation efficiency and high sugar content, the light intensity of the artificial light irradiated on the fruit and vegetable seedlings during the cultivation process is set to 200 μmol / m ２ / s~800μmol / m ２ / s, and 250 μmol / m ２ / s~600μmol / m ２ / s is more preferable. Light intensity is measured by placing a measuring device 1 cm away from the fruit or vegetable plant with the light-receiving surface facing the light source. Examples of measuring devices that can be used include a photon sensor (LI-COR, LI-190R). When light sources are positioned in two or more directions from the germinated fruit or vegetable plant, the sum of the light intensities measured by positioning the measuring device facing each light source is used as the light intensity. Light intensity can be controlled by changing the type and number of light sources (LEDs, fluorescent lamps, etc.) used, changing the distance between the light source and the fruit or vegetable plant, or using a dimmable light source. In the cultivation process, the fruit or vegetable plant can be cultivated using, for example, the hydroponic cultivation device shown in FIG. 2. Details of the hydroponic cultivation device will be described later.

[0027] Artificial light may be irradiated from above or from the side of the fruit vegetable seedlings, but is preferably irradiated from the side from the viewpoints of cultivation efficiency, space utilization efficiency, etc. Artificial light may also be irradiated from both the side and above.

[0028] From the viewpoint of shortening the time until harvest, the carbon dioxide concentration in the environment during the cultivation process is preferably 300 ppm to 2000 ppm, and more preferably 400 ppm to 1500 ppm. The carbon dioxide concentration is measured by placing a carbon dioxide concentration meter 1 cm away from the fruit vegetable plants. As the carbon dioxide concentration meter, for example, the LI-850 manufactured by LI-COR can be used. The method for controlling the carbon dioxide concentration is not particularly limited, and can be carried out by a conventionally known method. For example, the carbon dioxide concentration in the environment is monitored using the carbon dioxide concentration meter, and an air conditioner or the like can be used as necessary.

[0029] The period of the cultivation step is not particularly limited, but is preferably 70 to 300 days, more preferably 80 to 200 days, even more preferably 80 to 150 days, and particularly preferably 90 to 120 days. During the cultivation step, it is preferable to replace the nutrient solution, add liquid fertilizer, etc., as necessary, depending on the EC value and pH of the nutrient solution.

[0030] In the cultivation process, it is preferable to remove leaves below the tier where fruit harvesting is complete. By removing leaves below the tier where fruit harvesting is complete, cultivation efficiency can be improved. Side shoots on fruit and vegetable plants may be removed as appropriate (side shoot removal).

[0031] - Seedling raising step - The method for cultivating fruit and vegetable plants of the present disclosure can include a seedling raising step. In the seedling raising step, germinated fruit and vegetable plants are grown into fruit and vegetable plant seedlings. From the viewpoint of cultivation efficiency, the seedling raising of fruit and vegetable plants is preferably carried out by a hydroponic method, and more preferably by a submerged hydroponic method. From the viewpoint of cultivation efficiency, it is preferable to use a culture solution other than the specific culture solution in the seedling raising step, i.e., a culture solution having a Si content of less than 60 ppm by mass, more preferably a culture solution having a Si content of less than 30 ppm by mass, and even more preferably a culture solution having a Si content of less than 3 ppm by mass.

[0032] In the seedling raising process, light and dark periods can be switched by irradiating the germinating fruit and vegetable plants with artificial light, and it is preferable to adjust the temperature conditions between the light and dark periods. For example, two or more temperature conditions, light temperature and dark temperature, can be adjusted. From the viewpoint of shortening the period until bud formation, the upper limit of the light period temperature is preferably 29°C or less, more preferably 28.5°C or less, and even more preferably 28°C or less. From the viewpoint of shortening the period until bud formation, the lower limit of the light period temperature is preferably 15°C or more, more preferably 20°C or more, and even more preferably 25°C or more. From the viewpoint of shortening the period until bud formation, the upper limit of the dark period temperature is preferably 25°C or less, more preferably 23°C or less, and even more preferably 22°C or less. From the viewpoint of shortening the period until bud formation, the lower limit of the dark period temperature is preferably 10°C or more, more preferably 13°C or more, and even more preferably 15°C or more. The light source, wavelength, etc. of the artificial light can be those described in the cultivation process.

[0033] From the viewpoint of cultivation efficiency, high sugar content, etc., the ratio of light period time to dark period time (light period time / dark period time) is preferably 0.3 to 3, and more preferably 0.5 to 2.

[0034] From the viewpoint of cultivation efficiency, high sugar content, etc., the relative humidity during the seedling raising process is preferably controlled to 50% to 80%, and more preferably 55% to 77%.

[0035] From the viewpoint of cultivation efficiency and high sugar content, the light intensity of the artificial light irradiated on the germinating fruit and vegetable plants in the seedling raising process is set to 200 μmol / m ２ / s~800μmol / m ２ / s, and 250 μmol / m ２ / s~600μmol / m ２ It is more preferable that the ratio is / s.

[0036] Artificial light may be irradiated from above or from the side of the germinated fruit vegetable plants, but from the above is preferred from the viewpoints of cultivation efficiency, space utilization efficiency, etc. Artificial light may also be irradiated from both the side and above.

[0037] From the viewpoint of shortening the period until harvest, the carbon dioxide concentration in the environment during the seedling raising step is preferably 300 ppm to 2000 ppm, and more preferably 400 ppm to 1500 ppm.

[0038] The period of the seedling raising step is not particularly limited, but from the viewpoint of growth after planting, shortening the period until bud formation, etc., it is preferably 5 to 40 days, more preferably 10 to 35 days, even more preferably 12 to 30 days, and particularly preferably 15 to 33 days. During the seedling raising step, it is preferable to replace the nutrient solution, add liquid fertilizer, etc., as necessary, depending on the EC value and pH of the nutrient solution, etc.

[0039] In the seedling raising process, seedlings can be raised using a hydroponic cultivation apparatus shown in FIG. 1 . FIG. 1 is a schematic cross-sectional view showing one embodiment of the hydroponic cultivation apparatus. As shown in FIG. 1 , the hydroponic cultivation apparatus 10 for fruit and vegetable plants can include a support 12 for supporting fruit and vegetable seedlings 11, a panel 14 having holes 13 for fixing the support 12, and a nutrient solution tank 16 for containing nutrient solution 15. The hydroponic cultivation apparatus 10 for fruit and vegetable plants can also include a circulation mechanism 17 for supplying the nutrient solution 15 to the nutrient solution tank 16 and discharging the nutrient solution 15 from the nutrient solution tank 16. The circulation mechanism 17 can also include a circulation tank 18 for containing the nutrient solution 15, a supply nozzle 19 for supplying the nutrient solution 15 from the circulation tank 18 to the nutrient solution tank 16, a discharge nozzle 20 for discharging the nutrient solution 15 from the nutrient solution tank 16 to the circulation tank 18, and a pump P1. The hydroponic cultivation apparatus 10 for fruit and vegetable plants can also include an oxygen supply mechanism 21 in the nutrient solution tank 16. The fruit and vegetable plant hydroponic cultivation device 10 may also include an artificial light irradiation device 22. While Fig. 1 shows an artificial light irradiation device that irradiates artificial light from above and from the sides of the fruit and vegetable plant seedlings 11, the present invention is not limited to this.

[0040] - Germination step - The method for cultivating fruit and vegetable plants according to the present disclosure may include a germination step. In the germination step, seeds of the fruit and vegetable plants to be used in the seedling raising step are germinated. The germination method is not particularly limited, and can be carried out by a conventionally known method. For example, seeds of the fruit and vegetable plants are sown on the support that has been sufficiently moistened with water, and then stored in a dark place. It is also preferable to select seeds of fruit and vegetable plants that have been confirmed to have germinated and grow them at a similar growth rate, which allows the fruit to be harvested at the same time and improves cultivation efficiency.

[0041] The temperature for the germination process varies depending on the type and variety of fruit and vegetable plant used, but for commercially available seeds, this is generally disclosed as the germination temperature. Furthermore, if the germination temperature is unknown, it can be confirmed experimentally. Furthermore, depending on the type and variety of fruit and vegetable plant used, some require treatments such as breaking dormancy before germination. During the germination process, some require light of a specific wavelength, others require darkness, and others will germinate in either case. These can also be determined in the same way as the germination temperature.

[0042] The relative humidity during the germination process is preferably 70% to 100%, and particularly preferably 80% to 95%. By maintaining the humidity within this range, it is possible to prevent the plant body from drying out during the germination stage and promote good growth. The period required for the germination process is not fixed, but it is preferably the period from root formation to the start of subsequent hypocotyl elongation, which is often approximately several days to one week. By allocating this period to the germination process, it is possible to ensure sufficient root growth and prevent excessive hypocotyl elongation, resulting in good seedling growth during the subsequent seedling raising process and shortening the time until flowering, which is preferable.

[0043] In one embodiment of the method for cultivating fruit and vegetable plants of the present disclosure, the fruit and vegetable plant is a tomato. From the viewpoint of increasing the added value of the tomatoes, the Si content relative to the dry mass of the tomatoes harvested by the method for cultivating fruit and vegetable plants of the present disclosure is preferably 20 ppm by mass or more, more preferably 25 ppm by mass or more, and even more preferably 28 ppm by mass or more. In the present disclosure, the Si content relative to the dry mass of the tomatoes is measured by X-ray fluorescence analysis using crushed and dried tomato fruits as samples.

[0044] The ranges and preferred embodiments of the Brix sugar content and lycopene content of the tomatoes of the present disclosure will be described later.

[0045] [Tomato] The tomato according to the present disclosure has a Si content of 20 ppm by mass or more relative to the dry mass of the tomato and a Brix sugar content of 5.0% by mass or more. The tomato according to the present disclosure can be cultivated by the above-described method for cultivating fruit and vegetable plants according to the present disclosure. Furthermore, the cultivation of the tomato may use a culture solution for hydroponic cultivation of fruit and vegetable plants and a hydroponic cultivation device for fruit and vegetable plants, which will be described later.

[0046] The Si content relative to the dry mass of tomatoes is preferably high, more preferably 25 ppm by mass or more, and even more preferably 28 ppm by mass or more, from the viewpoint of increasing the added value of tomatoes.

[0047] Brix Sugar Content—The Brix sugar content of tomatoes is preferably 5.0% by mass or higher, more preferably 5.5% by mass or higher, even more preferably 6.0% by mass or higher, and particularly preferably 7.0% by mass or higher. In this disclosure, "Brix sugar content" refers to the refractive index measured at 20°C using a saccharometer or refractometer, converted into a mass percentage of the sucrose solution based on the conversion table of the International Commission on Uniform Methods of Sugar Analysis (ICUMSA). For example, if 100 g of solution contains x g of sucrose (water = 100 - x g), the Brix sugar content is x%. In this disclosure, the Brix sugar content of tomatoes is measured by cutting the tomatoes in half lengthwise (i.e., perpendicular to the equator), crushing one half into a liquid, and using the resulting liquid to measure the sugar content using a sugar content meter (Atago Sugar Content Meter).

[0048] Lycopene Content—The lycopene content of tomatoes is preferably 10 mg / 100 g or more, more preferably 12 mg / 100 g or more, and even more preferably 15 mg / 100 g or more. In the present disclosure, the lycopene content of tomatoes is measured by an absolute calibration curve method using a high performance liquid chromatograph.

[0049] [Culture solution for hydroponic cultivation of fruit and vegetable plants] The culture solution for hydroponic cultivation of fruit and vegetable plants according to the present disclosure contains sodium chloride and silicate, and has a Si content of 60 ppm by mass or more. Details of the Si content are as described above, so further description is omitted here. The culture solution for hydroponic cultivation of fruit and vegetable plants according to the present disclosure can be used in the above-described method for cultivating fruit and vegetable plants according to the present disclosure.

[0050] The preferred embodiments of the culture solution for hydroponic cultivation of fruit and vegetable plants are the same as the preferred embodiments of the specific culture solution, and therefore will not be described here.

[0051] [Hydroponic cultivation device for fruit and vegetable plants] The hydroponic cultivation device for fruit and vegetable plants according to the present disclosure includes a culture solution tank containing a culture solution for hydroponic cultivation of fruit and vegetable plants (specific culture solution). The hydroponic cultivation device for fruit and vegetable plants according to the present disclosure may also include an artificial light irradiation device.

[0052] When cultivating fruit and vegetable plants by hydroponic cultivation using a specific culture solution, after planting the fruit and vegetable seedlings, the hydroponic cultivation device for cultivating the fruit and vegetable plants using the specific culture solution can be, for example, the hydroponic cultivation device shown in Fig. 2. Fig. 2 is a schematic cross-sectional view showing one embodiment of the hydroponic cultivation device for fruit and vegetable plants of the present disclosure. One embodiment of the hydroponic cultivation device for fruit and vegetable plants according to the present disclosure will be described with reference to Fig. 2.

[0053] The fruit and vegetable hydroponic cultivation device 30 shown in Figure 2 is a cultivation device equipped with an LED lighting device 32, which is an artificial light irradiation device, a drip-type hydroponic cultivation mechanism 40, and a temperature and humidity control mechanism (not shown). The LED lighting device 32 is equipped with LED light sources, and five LEDs are arranged on each side of the plant 34 at intervals of 20 cm in a direction parallel to the direction of gravity (i.e., a total of 10 LEDs on both sides). This allows light to be irradiated onto the plant 34 from the side of the plant.

[0054] The drip-type hydroponic cultivation mechanism 40 includes a nutrient solution tank 42, a nutrient solution storage tank 46, and drip piping 50. The nutrient solution tank 42 contains nutrient solution for immersing the roots of the plants 34, and the contained nutrient solution is absorbed by the roots into the plants. One end of a discharge pipe 44 for discharging the contained nutrient solution is connected to the nutrient solution tank 42. A panel (not shown) having holes for fixing supports 52 is attached to the nutrient solution tank 42, and the plants 34 are supported by the supports 52 fixed to the holes. Here, a urethane support, which is an example of a support, is provided. The urethane support may be a residual urethane support used during sowing. The nutrient solution storage tank 46 includes a supply pipe 48 and stores the nutrient solution to be supplied to the nutrient solution tank 42. The other end of the discharge pipe 44, which is connected to the nutrient solution tank 42, is positioned above the surface of the nutrient solution in the nutrient solution storage tank 46. The nutrient solution is returned to the nutrient solution storage tank 46 from the other end of the discharge pipe 44 in accordance with the supply of nutrient solution from the supply pipe 48. The supply pipe 48 is equipped with a drive pump P, and by driving the drive pump P, the nutrient solution stored in the nutrient solution storage tank 46 can be supplied to the outside. The drip pipe 50 is equipped with a drip device at its tip and is connected to one end of the supply pipe 48. When the drive pump P is driven, the nutrient solution is sent through the supply pipe 48 to the drip device at the tip and dripped from the drip device to the nutrient solution tank 42. In the drip hydroponic cultivation mechanism 40, the nutrient solution tank 42, the nutrient solution storage tank 46, and the drip pipe 50 are connected to form a circulation system, and the nutrient solution is circulated and ready for use. The temperature and humidity control mechanism may be, for example, a thermo-hygrometer (or a thermometer and hygrometer) that can measure temperature and humidity, and a heating / cooling device and a humidifier that input signals of the measured temperature and humidity to adjust the temperature and humidity.

[0055] The above embodiment will be specifically described below using examples, but the above embodiment is not limited to these examples.

[0056] <Preparation of culture solutions A to D, N, and P to R for the hydroponic cultivation of fruit and vegetable plants> Culture solution A for the hydroponic cultivation of fruit and vegetable plants with a pH of 5 was prepared by adding a sodium silicate aqueous solution and dilute hydrochloric acid to the simple fertilizer. Culture solution B for the hydroponic cultivation of fruit and vegetable plants with a pH of 5 was prepared by adding a sodium silicate aqueous solution and dilute hydrochloric acid to the simple fertilizer. Culture solution C for the hydroponic cultivation of fruit and vegetable plants with a pH of 5 was prepared by adding a sodium silicate aqueous solution, sodium chloride, and dilute hydrochloric acid to the simple fertilizer. Culture solution D for the hydroponic cultivation of fruit and vegetable plants with a pH of 5 was prepared by adding dilute hydrochloric acid to the simple fertilizer. Culture solution N for the hydroponic cultivation of fruit and vegetable plants with a pH of 5 was prepared by adding dilute hydrochloric acid to the simple fertilizer. Culture solution P for the hydroponic cultivation of fruit and vegetable plants with a pH of 5 was prepared by adding a sodium silicate aqueous solution, sodium chloride, and dilute hydrochloric acid to the simple fertilizer. Sodium chloride and dilute hydrochloric acid were added to the single fertilizer to prepare culture solution Q for hydroponic cultivation of fruit and vegetable plants with a pH of 5. Sodium chloride and dilute hydrochloric acid were added to the single fertilizer to prepare culture solution R for hydroponic cultivation of fruit and vegetable plants with a pH of 5. The composition of each culture solution for hydroponic cultivation of fruit and vegetable plants is summarized in Table 1.

[0057]

[0058] Example 1 (Germination step) Tomato seeds (variety: Momotaro York (registered trademark), manufactured by Takii Seed Co., Ltd.) were sown on support A (5 cm × 5 cm × 2 cm polyurethane foam) sufficiently saturated with pure water, and stored in a dark environment at a temperature of 28°C and a relative humidity of 70% for 3 days to germinate, yielding tomato plants.

[0059] (Seedling raising process) The tomato plants obtained in the above germination process were transplanted into a hydroponic cultivation apparatus shown in Figure 1, which was equipped with an artificial light irradiation device and a culture solution tank containing the culture solution N for hydroponic cultivation of fruit and vegetable plants, and the seedlings were raised for 20 days by the submerged hydroponic method.

[0060] (Cultivation Process) Cultivation of the 40 resulting plants was initiated under the following condition 1 in the hydroponic cultivation apparatus for fruit and vegetable plants shown in FIG. 2. The hydroponic cultivation apparatus for fruit and vegetable plants shown in FIG. 2 is a cultivation apparatus including five light sources (i.e., 10 on each side) arranged 20 cm apart in the direction of gravity on both sides of the plant, a drip-type hydroponic cultivation mechanism, and a temperature and humidity control mechanism. During the cultivation period, top pinching, fruit thinning, and harvesting were performed according to the method described in paragraph 0058 of WO 2022 / 102328. After three inflorescences (first to third inflorescences) had formed on the main branch, two true leaves were confirmed to have developed above the third inflorescence, and then the top pinching was performed, leaving the true leaves. Each inflorescence was thinned to produce three fruits, and the tomato fruits that had borne fruit up to the third inflorescence were harvested, completing the cultivation. [Condition 1] Light source: Ryoden Corporation, plant growth LED 4-color type, PGL-200DWBF26D Light intensity: 500 μmol / m ２ ・s ・Light composition: Complies with the light emission behavior of the above LED ・Light / dark cycle (light period / dark period): 16 hours / 8 hours ・Temperature: 27°C (light period), 19°C (dark period) ・Relative humidity: 60% ・Carbon dioxide concentration: 1,000 ppm ・Nutrient solution for hydroponic cultivation of fruit and vegetable plants: A ・Fertilization method: Drip hydroponic

[0061] Example 2 Fruit and vegetable plants were cultivated in the same manner as in Example 1, except that the culture solution A for hydroponic cultivation of fruit and vegetable plants used in the cultivation was changed to the culture solution B for hydroponic cultivation of fruit and vegetable plants.

[0062] Example 3 Cultivation was started under the following Condition 2, and once flowering at the second inflorescence stage was confirmed, fruit and vegetable plants were cultivated in the same manner as in Example 1, except that the culture solution N for hydroponic cultivation of fruit and vegetable plants was changed to the culture solution C for hydroponic cultivation of fruit and vegetable plants. [Condition 2] Light / dark cycle: 16 hours (light) / 8 hours (dark) Light intensity: 500 μmol / m ２ / s ・Temperature: 27℃ (bright) / 19℃ (dark) ・Relative humidity: 70% ・CO2 concentration: 1,000ppm ・Culture solution for hydroponic cultivation of fruit and vegetable plants: N

[0063] Example 4 Fruit and vegetable plants were cultivated in the same manner as in Example 3, except that the culture solution C for hydroponic cultivation of fruit and vegetable plants used in the cultivation was changed to the culture solution D for hydroponic cultivation of fruit and vegetable plants.

[0064] Comparative Example 1 Fruit and vegetable plants were cultivated in the same manner as in Example 1, except that the culture solution A for hydroponic cultivation of fruit and vegetable plants used in the cultivation was changed to the culture solution N for hydroponic cultivation of fruit and vegetable plants.

[0065] Comparative Example 2 Fruit and vegetable plants were cultivated in the same manner as in Example 1, except that the culture solution A for hydroponic cultivation of fruit and vegetable plants used in the cultivation was changed to the culture solution P for hydroponic cultivation of fruit and vegetable plants.

[0066] Comparative Example 3 Fruit and vegetable plants were cultivated in the same manner as in Example 3, except that the culture solution C for hydroponic cultivation of fruit and vegetable plants used in the cultivation was changed to the culture solution Q for hydroponic cultivation of fruit and vegetable plants.

[0067] Comparative Example 4 Fruit and vegetable plants were cultivated in the same manner as in Example 3, except that the culture solution C for hydroponic cultivation of fruit and vegetable plants used in the cultivation was changed to the culture solution R for hydroponic cultivation of fruit and vegetable plants.

[0068] <<Evaluation>> [Average fruit number, average fruit weight, and average yield] Table 2 shows the average fruit number per plant, the average weight per fruit (average fruit weight), and the average weight of fruit harvested per plant (average yield) in the Examples and Comparative Examples.

[0069] [Brix sugar content] Harvested tomatoes were cut in half lengthwise (i.e., perpendicular to the equator), and one half of the tomato was crushed into a liquid (juice-like substance). The resulting juice was measured using a sugar content meter (Atago Sugar Content Meter). Measurements were performed on all the harvested tomatoes, and the average of the measured values ​​was used as the Brix sugar content. The measurement results are shown in Table 2.

[0070] [Si content] The fruits obtained during the above average Brix sugar content measurement were crushed, and a portion of the juice was dried and formed into tablets. These samples were used to measure the Si content relative to the dry mass of the tomatoes using X-ray fluorescence analysis. The measurements were performed on all the harvested tomatoes, and the average value of the measured values ​​was used as the Si content. The measurement results are shown in Table 2.

[0071] [Lycopene Content] The fruits obtained during the measurement of average Brix sugar content were crushed, and a portion of the juice was used to measure the lycopene content by high performance liquid chromatography. The measurement results are shown in Table 2.

[0072] [Sensory Evaluation] For the above [Brix sugar content], harvested tomatoes were cut in half lengthwise on any plane (i.e., the other half of the tomato) was used for the sensory evaluation. Ten male and female evaluators, aged 20 to 50 years, tasted the tomatoes obtained in the Examples and Comparative Examples and rated their taste on a 10-point scale (1 to 10). The tasting was performed using fruit samples cut into 1 / 8 pieces to form half-moon shapes, with each evaluator tasting at least two pieces. The cultivating conditions for Comparative Example 1 were disclosed to the evaluators, but the other cultivating conditions were not disclosed to the evaluators. The tomato in Comparative Example 1 was given a score of 5. Each evaluator tasted and evaluated all fruit samples sequentially on the same day. The evaluation results were not disclosed until all evaluators had finalized their scores, and the evaluators were not allowed to discuss them with each other. The average scores are summarized in Table 2.

[0073]

[0074] The disclosure of Japanese Patent Application No. 2023-027721, filed on February 24, 2023, is incorporated herein by reference in its entirety. All publications, patent applications, and technical standards mentioned herein are incorporated herein by reference to the same extent as if each individual publication, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A method for cultivating fruit and vegetable plants, comprising cultivating the fruit and vegetable plants by a hydroponic method using a culture solution having a Si content of 80 mass ppm or more and an electrical conductivity of 4.5 ds / m or more.

2. The method for cultivating fruit and vegetable plants according to claim 1 , wherein the culture solution contains a silicate.

3. The method for cultivating fruit vegetables according to claim 1 or 2, wherein the culture solution contains sodium chloride.

4. The method for cultivating fruit and vegetable plants according to claim 1 or 2, wherein the cultivation of the fruit and vegetable plants by hydroponic method is carried out at least after planting of fruit and vegetable plant seedlings.

5. Light intensity 200μmol / m ２ / s~800μmol / m ２ 5. The method for cultivating fruit vegetable plants according to claim 4, comprising irradiating the fruit vegetable plant seedlings with artificial light of 1000 nm / s.

6. 6. The method for cultivating fruit and vegetable plants according to claim 5, wherein the artificial light is applied from at least one of a side surface and an upper surface of the fruit and vegetable plants.

7. The method for cultivating a fruit vegetable according to claim 1 or 2, wherein the fruit vegetable is a tomato or a melon.

8. The fruit vegetable plant is a tomato, The method for cultivating a fruit vegetable plant according to claim 1 or 2, wherein the tomato has a Si content of 20 ppm by mass or more relative to the dry mass of the tomato.

9. A tomato having a Si content of 20 ppm by mass or more and a Brix sugar content of 5.0% by mass or more relative to the dry mass of the tomato.

10. A culture solution for hydroponic cultivation of fruit and vegetable plants, comprising sodium chloride and a silicate, having a Si content of 80 ppm by mass or more, and an electrical conductivity of 4.5 ds / m or more.

11. A fruit vegetable hydroponic cultivation device comprising a culture solution tank containing the culture solution for hydroponic cultivation of fruit vegetable plants described in claim 10.