JP6532368B2 - Plant cultivation apparatus and plant cultivation method - Google Patents

Description

  The present invention relates to a plant cultivation apparatus and a plant cultivation method, and more particularly to a plant cultivation apparatus and a plant cultivation method used for cultivating a plant in a space in which the internal environment is controlled.

DESCRIPTION OF RELATED ART Conventionally, the plant factory which can produce a plant systematically in the closed or semi-closed space which controlled the internal environment for the purpose of the anniversary supply of a safe foodstuff is widely known. In plant factories, plants are generally grown using artificial light as a light source using hydroponic culture, and the productivity of vegetables and fruits is improved by controlling the temperature, humidity, carbon dioxide concentration, etc. in the space. There is.
In order to further increase the growth of fruit plants in order to further increase the yield of fruits such as fruits and vegetables in this plant factory, light quality (wavelength composition of light) acting on the morphogenesis of fruit plants It is known to control light intensity (see, for example, Patent Document 1).

In the plant cultivation method described in Patent Document 1, a step of irradiating a plant with red light and a step of irradiating a plant with blue light are performed, and the light irradiation time of each step is set to 3 hours or more and less than 48 hours. It is disclosed that an irradiation cycle consisting of an irradiation step and a blue light irradiation step is performed for two or more cycles within a fixed period.
According to the said cultivation method, the outstanding growth promotion effect can be acquired.

JP, 2015-119732, A

By the way, among plants, fruit plants having fruits in particular generally have a long cultivation period until harvest, a vegetative growth period (for example, increase in number of leaves, height of leaves), and a reproductive growth period (for example, flower bud formation) Flowering, fruit formation), and the growth process is relatively complicated.
If it is possible to optimize the light quality and light intensity of artificial light according to the growth degree of fruit plants in consideration of such a complicated growth process, it is possible to further promote the growth of fruit plants. is there.
However, in the plant cultivation method as disclosed in Patent Document 1, although a device is disclosed in which the step of irradiating red light to the plant and the step of irradiating blue light are performed in a plurality of cycles within a certain period, The red irradiation and the blue irradiation were switched depending on the irradiation time of Therefore, there was a possibility that it could not necessarily irradiate with artificial light which consists of suitable light quality and light intensity according to a growth degree of a plant.
In addition, irradiating a plant with light of different light quality or light intensity for a plurality of cycles may result in relatively complicated control, and may also cause problems in plant adjustment for photosynthesis.

The present invention has been made in view of the above problems, and the object of the present invention is to effectively promote the growth of plants by irradiating light in consideration of the growth process of plants, particularly fruit plants. Plant cultivation apparatus and plant cultivation method that can be
Another object of the present invention is a plant cultivation apparatus and a plant cultivation method capable of promoting the growth of the plant by irradiating the plant with light of different light quality and light intensity in a simple process. It is to provide.

  According to the plant cultivation apparatus of the present invention, the above-mentioned subject is a white light irradiation part which irradiates white light to a plant, a blue light irradiation part which irradiates blue light, and a red light irradiation part which irradiates red light And a light control unit configured to control the light irradiation unit according to the degree of growth of the plant, the light control unit performing the white light irradiation by the white light irradiation unit. Second control for simultaneously performing control, white light irradiation by the white light irradiation unit, and blue light irradiation by the blue light irradiation unit, white irradiation by the white light irradiation unit, and red irradiation by the red light irradiation unit And a third control that simultaneously performs and one cycle of sequentially executing.

With the above configuration, by irradiating light in consideration of the growth process of a plant, it is possible to realize a plant cultivation apparatus capable of effectively promoting the growth of the plant.
Specifically, when controlling the light-irradiated part according to the degree of growth of a plant, the number of leaves that are important in the initial cultivation stage (vegetative growth stage) of the plant is first obtained by irradiating the plant with only white light. And increase leaf height.
After that, by simultaneously irradiating the plant with white light and blue light, while promoting the increase in the number of leaves and the height of the leaves of the plant, at the same time, it promotes the flowering and flowering of the main stalk which is important in the early stage of reproductive growth period be able to.
Then, by simultaneously irradiating the plant with white light and red light, while promoting the increase in the number of leaves and height of the plant, at the same time the formation of side shoots that are important in the late stage of the reproductive growth stage, from side shoots It can promote flower bud formation and flowering. As a result, it is possible to promote the growth of plants from the main stem to the branches (armors) for a long period of time.
In addition, with the above configuration, growth of the plant can be promoted by effectively irradiating the plant with light of different light quality in a simple process of one cycle.

At this time, the plant is preferably a fruit plant having a fruit.
According to the above-mentioned configuration, it is possible to effectively promote the growth of fruit plants in plants, in particular, the growth process is relatively complicated, and the cultivation period until harvest is prolonged. As a result, fruits can be harvested over a long period from the main stem to the branches, and the yield can be increased.

At this time, the light control unit ends the first control and starts the second control when the leaves of the main stem in the plant become larger than a predetermined size, and the second stem starts flowering in the plant. When the second control is finished, the second control may be finished and the third control may be started.
According to the above configuration, it is possible to simultaneously irradiate white light and blue light when the leaves of the main stem become larger than a predetermined size and immediately before the formation of flower buds (when immediately before the reproductive growth period). In addition to increasing the number of leaves and height of plants, it can promote flower bud formation and flowering of the main stem.
In addition, it is possible to irradiate white light and red light at the same time when the flower bud of the main stem of the plant finishes flowering and it is time to start the enlargement of the fruit, in addition to the increase in leaf number and height of the plant. It can promote side bud formation, flower bud formation and flowering from the side bud. As a result, it becomes a plant cultivation apparatus which considered the growth process of a plant more.

At this time, in the second control, the light intensity ratio between the white light and the blue light is 2: 1 to 4: 1, and in the third control, the light intensity ratio between the white light and the red light is , 2: 1 to 4: 1.
The light intensities of the blue light and the red light may be 50 to 70 μmol / m ² s of photosynthetic photon flux density.
According to the above configuration, the growth of the plant can be further promoted by effectively irradiating the plant with light having different light intensities as well as the light quality.

At this time, the light control unit includes a detection unit that detects a physical property value that changes in accordance with the degree of growth of the plant, and the physical property value detected by the detection unit reaches a first threshold. It is preferable to finish the first control and start the second control, and finish the second control to start the third control when the physical property value detected by the detection unit reaches a second threshold.
By the said structure, control of a light irradiation part can be performed by the switching timing with high precision, and the growth of a plant can be promoted further.
In addition, as a detection method of the physical-property value which changes according to the growth degree of a plant, the method of detecting the form of a plant by image sensing, the method of detecting ethylene concentration of a plant, for example, A method of detecting the ultraviolet reflectance of

  Moreover, it is a plant cultivation method which irradiates predetermined light with respect to the said plant according to the growth degree of a plant, Comprising: The 1st process of performing white light irradiation, white light irradiation, and blue light irradiation simultaneously It is also possible to realize a plant cultivation method which comprises two steps, and a third step simultaneously performing white irradiation and red irradiation, and performing one cycle of the steps from the first step to the third step.

According to the plant cultivation apparatus and the plant cultivation method of the present invention, the growth of the plant can be effectively promoted by irradiating light in consideration of the growth process of the plant, particularly the fruit plant.
In addition, the growth of the plant can be promoted by irradiating the plant with light of different light quality and light intensity in a simple process.

It is a figure explaining the plant cultivation apparatus of this embodiment. It is a figure explaining the procedure of the light control by a plant cultivation apparatus, and the mechanism of an effect. It is a graph which shows the result of Experiment 1-1, and is a figure which shows the influence which blue supplementary light gives to the flower bud number of a raspberry (Indian summer). It is a graph which shows the result of Experiment 1-2, Comprising: It is a figure which shows the influence which blue supplementary light gives to the flower bud number of a raspberry (Indian summer). It is a graph which shows the result of Experiment 1-3, Comprising: It is a figure which shows the influence which blue supplementary light gives to the flower bud number of raspberry (heritage). It is a graph which shows the result of Experiment 2-1, Comprising: It is a figure which shows the influence which a red supplementary light gives to the flower bud number of a raspberry (Indian summer). It is a graph which shows the result of Experiment 2-2, Comprising: It is a figure which shows the influence which a red supplementary light gives to the flower bud number of a raspberry (heritage).

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 7.
In the present embodiment, a light irradiation unit including a white light irradiation unit that irradiates white light to a fruit plant, a blue light irradiation unit that irradiates blue light, and a red light irradiation unit that irradiates red light; And a light control unit that controls the light irradiation unit according to the degree of growth of the fruit plant, and the light control unit performs the first control that performs the white light irradiation, and the first that performs the white light irradiation and the blue light irradiation simultaneously. The present invention relates to the invention of a plant cultivation apparatus characterized in that 2 control and third control simultaneously performing white irradiation and red irradiation are sequentially performed in one cycle.

<Configuration of plant cultivation apparatus>
The plant cultivation apparatus 1 is used to systematically produce fruit plants in a closed or semi-closed space (in a plant factory) in which the internal environment is controlled.
As shown in FIG. 1, the plant cultivation apparatus 1 is formed of a relatively small box having a substantially rectangular parallelepiped shape, and the cultivation apparatus body 10 for placing a cultivation tray for fruit plant cultivation, and the cultivation apparatus body 10 A light irradiation unit 20 attached to the upper part, which irradiates light with different light quality and light intensity to the fruit plant planted in the cultivation tray from above, and the light irradiation unit 20 according to the growth degree of the fruit plant And a light control unit 30 to control the image.

  The light irradiator 20 is an LED illumination, and is a white light irradiator 21 that emits white light to fruit plants, a blue light irradiator 22 that emits blue light as a supplemental light, and red light as a supplemental light. And a red light irradiator 23 for emitting light.

The light control unit 30 is a controller that controls the light quality and light intensity of the light irradiation by the light irradiation unit 20, and is connected to the light irradiation unit 20 and the power supply 40, respectively.
The light control unit 30 includes detection sensors 31 and 32 that detect physical property values that change according to the degree of growth of the fruit plant, receives a detection signal based on the physical property values from the detection sensors 31 and 32, and detects light. Control of the light emitting unit 20 is executed by transmitting a control signal to the irradiating unit 20.

Specifically, the light control unit 30 simultaneously performs first control for performing white light irradiation by the white light irradiation unit 21, and simultaneously performs white light irradiation by the white light irradiation unit 21 and blue light irradiation by the blue light irradiation unit 22. The second control and the third control for simultaneously performing the white irradiation by the white light irradiation unit 21 and the red irradiation by the red light irradiation unit 23 are sequentially executed for one cycle.
Then, when the physical property value detected by the detection sensor 31 reaches the first threshold, the light control unit 30 ends the first control and starts the second control, and the physical property value detected by the detection sensor 32 When the second threshold value is reached, the second control is ended and the third control is started.

The detection sensor 31 is, for example, a known image sensor that identifies an object from an image and detects the size of the object as a physical property value.
The detection sensor 31 of the present embodiment detects the largest leaf of the main stem (for example, the leaf at the third top position) in the fruit plant as an object, and detects the size of the leaf as a physical property value.
Then, the light control unit 30 determines that the first threshold has been reached when the largest leaf of the main stem has reached a predetermined size (for example, about 5 cm), and ends the first control to perform the second control. To start.

The detection sensor 32 is, for example, a known gas sensor that detects the value of ethylene concentration in a predetermined space.
The detection sensor 32 of this embodiment detects the value of the ethylene concentration of the fruit plant in the cultivation apparatus main body 10, particularly the value of the ethylene concentration near the main stem of the fruit plant as a physical property value.
Then, the light control unit 30 takes advantage of the fact that the amount of ethylene secretion of the fruit plant changes through its maturation process, and the flower stalk of the main stalk (for example, the flower stalk in the third position from the top) The second threshold is set as a predetermined value of the ethylene concentration at which the hypertrophy of the blood flow begins, and the second control is ended and the third control is started when the second threshold is reached.

  The method of detecting physical property values that change according to the degree of growth of the fruit plant by the detection sensors 31 and 32 can be changed without particular limitation. For example, when the fruit plant is irradiated with ultraviolet light Well-known detection methods, such as a method of detecting an ultraviolet reflectance, can be adopted.

  In addition, as a timing which the light-control part 30 complete | finishes 3rd control, it is good also as a timing which the flower bud of a side bud finishes flowering and the enlargement of a fruit begins, the timing which harvests a fruit, As well. Then, a predetermined value of the physical property value based on the timing may be set as a third threshold, and the light control unit 30 may be controlled to end the third control when the third threshold is reached.

<Light quality and light intensity of light irradiation part>
Next, details of light quality (light color) and light intensity of the light irradiation unit 20 will be described.
The white light irradiated by the white light irradiation unit 21 is light in which light of all wavelengths of visible light including blue light and red light is uniformly mixed, and in the present embodiment, the light intensity is about 160. It is set at a photosynthetic photon flux density of ̃180 μmol / m ² s.
A pigment called chlorophyll (chlorophyll) is greatly involved in the photosynthesis of plants, and according to the action spectrum of plant photoreaction, there are two in red light (about 660 nm wavelength) and blue light (about 450 nm wavelength) Absorbing peaks are present, and these wavelengths have been found to be particularly effective for photosynthesis. That is, for healthy growth of plants, it is desirable to irradiate white light in which red light and blue light are blended in a well-balanced manner.
In the present embodiment, as shown in FIG. 2, white light is always emitted from the initial cultivation stage of the fruit plant through the vegetative growth stage, the reproductive growth stage and the late cultivation stage. Therefore, growth of a fruit plant can be promoted over a long period of time. In particular, irradiation with white light can promote increase in the number of leaves and height of leaves in fruit plants.

The blue light irradiated by the blue light irradiation unit 22 is light having a wavelength of about 400 to 500 nm (the center wavelength is about 450 to 470 nm), and in the present embodiment, the light intensity is about 50 to 70 μmol. It is set at a photosynthetic photon flux density of / m ² s.
The irradiation of blue light can promote flower bud formation and flowering of main stems to plants.
The mechanism is briefly described. By irradiating a plant with blue light, first, cryptochrome which is one of blue light receptor proteins in the plant is activated, and CO protein is stably accumulated in the plant. The CO protein promotes transcription of the FT gene involved in flower hormone, resulting in the promotion of flower hormone.
In this example, as shown in FIG. 2, when it comes just before the reproductive growth stage of the fruit plant, specifically the leaf of the main stalk becomes larger than a predetermined size and becomes just before the formation of flower buds Sometimes blue light is simultaneously irradiated as a supplement to white light. Therefore, it can promote the flower bud formation and the flowering of the main stem which are important in the early stage of the reproductive growth stage.

The red light irradiated by the red light irradiation unit 23 is light having a wavelength of about 600 to 700 nm (about 650 to 680 nm as a central wavelength), and in the present embodiment, the light intensity is about 50 to 70 μmol. It is set at a photosynthetic photon flux density of / m ² s.
Irradiation of red light can promote the formation of side buds, and the formation and flowering of flower buds from the side buds.
Briefly explaining the mechanism, when a plant is irradiated with red light, phytochrome, which is one of the red light receptor proteins in the plant, is activated to induce the synthesis of the plant hormone, gibberellin, in the plant. The accumulation and activation of gibberellin in the plant body can promote the growth of side buds and further promote flowering from the side buds.
In the present embodiment, as shown in FIG. 2, when it comes to the late stage of the reproductive growth stage of the fruit plant, specifically, it becomes the timing when the flower bud of the main stem of the plant finishes flowering and the enlargement of the fruit starts. At the same time, red light is simultaneously irradiated as a supplement to white light. Therefore, it is possible to promote the formation of side shoots that are important in the late reproductive and developmental stages, and the formation and flowering of flower shoots from the side shoots.

The flower bud formation mechanism of a plant has several independent pathways, blue light is involved in the photoperiod-dependent promotion pathway, and red light is involved in the gibberellin-dependent promotion pathway.
In the present embodiment, the blue supplemental light by the blue light emitting unit 22 and the red supplemental light by the red light emitting unit 23 are separately and sequentially irradiated with light. Therefore, the photoperiod-dependent promoting pathway and the gibberellin-dependent promoting pathway can be promoted at different timings, and flower bud formation can be performed intermittently.

Next, the intensity ratio of irradiated light will be described. When blue light is simultaneously irradiated with white light, the light intensity ratio between white light and blue light is 2: 1 to 4: 1, preferably 2.2: 1. It is desirable that it is -3.6: 1.
When irradiating red light simultaneously with white light, the light intensity ratio between white light and red light is 2: 1 to 4: 1, preferably 2.2: 1 to 3.6: 1. Is desirable.

<Other Embodiments>
Although it is used in order to grow fruit plants, such as a fruit tree and fruit vegetables, in plant cultivation device 1 of the above-mentioned embodiment, it is not limited to cultivation of a fruit plant in particular, but is widely used to grow plants Also good.
Desirably, it is good to be used for cultivating fruit trees such as berries, figs, olives, oysters, citrus fruits, kiwis, chestnuts, loquats, feijoas, grapes, or apples. In these fruit trees, leaf buds are plants which sprout at almost the same time as flower buds or earlier.
Furthermore, it is preferable that the vegetable be used for cultivating fruits and vegetables classified into long day plants and short day plants. On the other hand, for Chinese and Japanese plants that flower and set fruit regardless of the day length, the sensitivity to light and the way of contribution to the flower bud formation of photoreceptors differ, and the effect of the present invention may not be obtained.

  Moreover, in the said embodiment, although the light irradiation part 20 is LED illumination, it can change without being specifically limited, for example, a white fluorescent lamp, a color fluorescent lamp, etc. may be sufficient. And since the white light irradiation part 21 always irradiates light to a plant, it may be sunlight.

Moreover, in the said embodiment, although the emitted light ratio (component ratio of light) of the blue light with respect to irradiated light is 100%, the irradiation light by the blue light irradiation part 22 can be changed, without being specifically limited.
For example, if the emission intensity ratio of blue light to irradiation light is 60% or more, light other than blue light may be included.
Similarly, the emission light ratio of the red light to the irradiation light (component ratio of light) is 100%, but the irradiation light by the red light irradiation unit 23 can be changed without being particularly limited.
For example, if the emission intensity ratio of red light to irradiation light is 60% or more, light other than red light may be included. It can be changed without being particularly limited.

<Example>
Hereinafter, an embodiment of the present invention will be described in detail. The present invention is not limited to this embodiment.
Raspberry (Indian summer) and raspberry (Heritage) were employed as the fruit plants of this example. Both purchased seedlings dormant in winter and woke up from dormancy in the plant factory. The temperature in the plant factory was set at 20 ° C. in the light, 15 ° C. in the dark, 14 hours in the light, and 10 hours in the dark.

Test Example 1 Verification Test of Influence of Blue Supplementation on Flower Bud Number of Raspberry
White light was entirely irradiated from directly above the plant using the white light irradiation section 21 as a light source, and at the same time blue light was supplemented by the blue light irradiation section 22 to the leaves of the sprout part where the leaves reached about 5 cm in size .
The blue light was locally irradiated only to the sprout part, and the distance from the leaf surface to the light irradiation part 20 was opened by about 5 cm so that the leaves would not be burnt by the illumination heat.
Supplementing with blue light is performed simultaneously with lighting of white light, and the light intensity of only white light is 160 to 180 μmol / m ² s at the leaf surface, and the light intensity of only blue light is about 50 to 70 μmol / m ² at the leaf surface s.

<< Test Example 1-1 >>
Raspberry (Indian summer) is grown in the above plant factory, and 21 days after the start of irradiation with blue light, Control area (Control) not supplied with light and Blue area supplied with light (Blue) Flower bud numbers were compared.
In this test, 3 strains of raspberry were tested in the Control section, and 1 strain was tested in the Blue section.
The test results are shown in FIG. In the Blue section, which was supplemented with blue light, the number of flower shoots was about twice that of the Control section.

<< Test Example 1-2 >>
The test was conducted under the same test conditions as Test Example 1-1, and the reproducibility of the test results of Test Example 1-1 was confirmed.
In this test, 3 strains of raspberry were tested in both the Control section and the Blue section.
The test results are shown in FIG. In the Blue section given the blue light supplementation, the number of flower shoots was about 5 times that of the Control section.

<< Test Example 1-3 >>
The test was conducted under the same test conditions as in Test Example 1-1, and it was confirmed whether the test results of Test Examples 1-1 and 1-2 were applicable even if they were different varieties (heritage) of raspberry.
In this test, 1 strain of raspberry (heritage) was tested in both the Control section and the Blue section.
The test results are shown in FIG. As in the test results of Test Examples 1-1 and 1-2, in the Blue section, more flower buds were formed than in the Control section.

(Discussion of Test Example 1)
From the test results of Test Examples 1-1 to 1-3, it was found that the formation of raspberry flower buds was promoted by the supplementation of blue light with a light intensity of about 50 to 70 μmol / m ² s.
Specifically, when the raspberry leaf is about 5 cm in size and immediately before the formation of flower buds (when it is just before the reproductive stage), the raspberry is simultaneously irradiated with white light and blue light It was found that the formation of raspberry flower buds was promoted.

Test Example 2 Verification Test of Effect of Red Supplementation on Flower Bud Number of Raspberry
White light was entirely irradiated from directly above the plant with the white light irradiation section 21 as a light source, and at the same time red light irradiation section 23 supplemented red light to the leaves of the sprout part where the leaves reached about 5 cm in size .
The red light was locally irradiated only to the sprout part, and the distance from the leaf surface to the light irradiation part 20 was opened by about 5 cm so that the leaves would not be burnt by the illumination heat.
Supplementing with red light is performed simultaneously with lighting of white light, and the light intensity of only white light is 160 to 180 μmol / m ² s at the leaf surface, and the light intensity of only red light is about 50 to 70 μmol / m ² at the leaf surface s.

<< Test Example 2-1 >>
Raspberry (Indian summer) is grown in the above plant factory, and the red control section (Control section) which does not receive the correction light and the red section which receives the correction light (21 days and 42 days after the start of the irradiation of the red correction light) The number of flower buds was compared with Red).
In this test, 1 strain of raspberry was tested in both the Control section and the Red section.
The test results are shown in FIG. Twenty-one days after the start of the light addition, there was no difference in the number of flower buds between the Red and Control areas to which the red light was added. Forty-two days after the start of supplementary light, the number of flower buds in Red area was about twice that of Control area.

<< Test Example 2-2 >>
The test was conducted under the same test conditions as Test Example 2-1, and it was confirmed whether the test result of Test Example 2-1 was applicable even if it was a different variety (heritage) of raspberry.
In this test, 1 strain of raspberry (heritage) was tested in both the Control section and the Red section.
The test results are shown in FIG. Similar to the test results of Test Example 2-1, there was no difference in the number of flower shoots between Red and Control after 21 days from the start of light supplementation. Forty-two days after the start of light adjustment, the Red area had more flower buds than the Control area.

(Discussion of Test Example 2)
In the test examples 2-1 and 2-2, raspberry was observed for the reason that the number of flower buds in the Red section irradiated with red light was increased, and many side buds were generated from the main stem, and many flower buds were formed in the side buds. It was
From the test results of the test examples 2-1 and 2-2 and the above observation results, the red light having a light intensity of about 50 to 70 μmol / m ² s promotes the side bud growth of raspberry, and the blue light Over time it has been found to be effective in increasing the number of flower buds.
Specifically, when the flower buds of the raspberry's main stem have finished flowering and it is time to start fruit enlargement (at the late stage of the reproductive growth period), the white light and red light are simultaneously applied to the raspberry It was found that irradiation accelerated the formation and growth of side sprouts of raspberry.

DESCRIPTION OF SYMBOLS 1 plant cultivation apparatus 10 cultivation apparatus main body 20 light irradiation part 21 white light irradiation part 22 blue light irradiation part 23 red light irradiation part 30 light control part 31, 32 detection sensor (detection part)
40 power supply

Claims (7)

A light emitting unit having a white light emitting unit for emitting white light to a plant, a blue light emitting unit for emitting blue light, and a red light emitting unit for emitting red light;
A light control unit configured to control the light irradiation unit according to the growth degree of the plant;
The light control unit
First control for performing white light irradiation by the white light irradiation unit;
A second control that simultaneously performs white light irradiation by the white light irradiation unit and blue light irradiation by the blue light irradiation unit;
The plant cultivation apparatus which performs 1 cycle of 3rd control which performs simultaneously white irradiation by the said white light irradiation part, and red irradiation by the said red light irradiation part in order one cycle.   The plant growing apparatus according to claim 1, wherein the plant is a fruit plant having a fruit. The light control unit
The first control is ended and the second control is started when the leaves of the main stem in the plant become larger than a predetermined size,
The plant cultivation apparatus according to claim 1 or 2, wherein the second control is ended and the third control is started when the flower stalk of the main stem in the plant ends flowering. In the second control, the light intensity ratio between the white light and the blue light is 2: 1 to 4: 1,
The plant cultivation device according to any one of claims 1 to 3, wherein a light intensity ratio between the white light and the red light is 2: 1 to 4: 1 in the third control. The plant cultivation apparatus according to any one of claims 1 to 4, wherein light intensities of the blue light and the red light are 50 to 70 μmol / m ² s of photosynthetic photon flux density. The light control unit
A detection unit that detects physical property values that change according to the growth degree of the plant;
The first control is terminated and the second control is started when the physical property value detected by the detection unit reaches a first threshold value,
The second control is terminated and the third control is started when the physical property value detected by the detection unit reaches a second threshold value. Plant cultivation apparatus as described. It is a plant cultivation method which irradiates predetermined light to said plant according to a growth degree of a plant,
A first step of irradiating white light;
A second step of simultaneously performing white light irradiation and blue light irradiation;
Providing a third step of simultaneously performing white irradiation and red irradiation;
A plant cultivation method comprising performing one cycle of the steps from the first step to the third step.

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