JP2010279295A - Method and device for cultivating tea tree - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device each for cultivating tea trees by and with which a cumulative dose of full flavor components is relatively simply increased further while suppressed in generation of astringent components. <P>SOLUTION: The device for cultivating tea trees is structured as follows: a plurality of light projectors 5, 5, ... are disposed at the inside ceiling position inside a shading member 31 so as to illuminate light to tea trees C, C, ... from respective light projectors 5, 5, ...; the power source part 2 of a power feeder 1 supplies electric power to the light projectors 5, 5, ...; the power feeder 1 is provided with a control part 3 controlling power supply/power supply stop to the light projectors 5, 5, .... With the device, the tea trees are illuminated with weak light at night during the time of elongation of sprouts of the tea trees to perform so-called supplemental lighting where light is supplemented to the tea trees. Such supplemental lighting is performed by illuminating light having an appropriate lighting intensity of ≤100 lx in average at the surface of the tree crowns of the tea trees. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for cultivating tea trees as raw materials such as strawberry tea, gyokuro or sencha, and a tea tree cultivation apparatus applied to the method.

Tea leaves in Japan are widely used for beverages or confectionery materials, but there is a demand for production of tea leaves with less astringency and better quality.
Tea umami components are mainly amino acids such as theanine (glutamic acid ethylamide), glutamic acid, arginine, and theanine is a typical component. Theanine is produced in the roots of tea trees, moves to shoots, and accumulates there. On the other hand, tea astringent ingredients are mainly catechins such as tannins.

  By the way, if the shoots are exposed to light with an illuminance higher than a predetermined value, theanine accumulated in the shoots will be converted into catechins by biosynthesis, so the accumulated amount of theanine decreases and the catechins are contained. The amount increases. Therefore, in tea trees used for the production of strawberry tea or gyokuro etc., shading cultivation is started in which the shoots are grown in the dark for a period of about 16 to 20 days. Has been done. (Thus, biosynthesis from theanine to catechins, which are astringent components, can be suppressed, the amount of theanine accumulated can be increased, and tea leaves with less astringency and better quality can be produced.

  On the other hand, soil improvement material consisting of hydrophilic high molecular organic polymer and humic acid, minerals such as Fe, Cu, Zn, B, Mn, Mo, ultra-trace minerals such as Se, V, Cr, Co, etc. A method has been proposed in which the amount of umami components extracted from tea leaves is increased by irrigating tea tree cultivation soil and cultivating tea trees (see, for example, Patent Document 1).

JP 2007-44010 A

  In such tea plants, it is required to further increase the accumulation amount of umami components while suppressing astringency components. Moreover, even in tea plants used for the production of sencha, it is required to improve the quality by further increasing the amount of umami components accumulated.

  In order to respond to such demands, in the case of tea trees for so-called undercover tea such as matcha or gyokuro, a method of extending the period of light-shielded cultivation is conceivable, but light-shielded cultivation is very difficult for tea trees that grow by photosynthesis. Therefore, there is a problem in that, when the period of shading cultivation is extended, the fallen leaves are invited and the growth of the tea tree is inhibited.

  Moreover, since the tea tree for sencha is usually not subjected to light-shielding cultivation, the light-shielding period cannot be adjusted. Here, it is conceivable to apply light-shielding cultivation to tea plants for sencha. However, light-shielding cultivation requires expensive equipment costs and a lot of labor, and it is an advanced technology that appropriately adjusts the light-shielding period and the light-shielding rate. Cost effectiveness is not consistent because it requires cultivation techniques.

  On the other hand, in the method proposed in Patent Document 1, much work is required for irrigation into the cultivated soil, and the types of soil improvers, minerals, and ultra-trace minerals according to the soil in each region where tea trees are grown. And it is very difficult to determine the amount. Moreover, there was a possibility that the production of astringency components could not be suppressed.

  The present invention has been made in view of such circumstances, and a tea tree cultivation method capable of increasing the accumulation amount of umami components more easily while suppressing the production of astringency components, and the method A tea tree cultivation apparatus to be applied to is provided.

  (1) The tea tree cultivation method according to the present invention is a method for cultivating a tea tree for harvesting tea leaves, wherein the average illuminance on the crown surface of the tea tree is 100 lx or less at night during the shoot growth stage of the tea tree. It is characterized by irradiating the tea tree with light.

  In the tea tree cultivation method of the present invention, supplemental light that irradiates light with an appropriate illuminance of an average of 100 lx (lux) or less on the crown surface formed at the tips of a plurality of branches constituting the tea tree at night. Do.

By supplementing tea plants at night, the accumulation amount of free amino acids including theanine can be increased while suppressing the production of catechins.
By irradiating tea trees with an average light of 100 lx or less at night, the tea tree that performs photosynthesis can be activated and theanine can be transferred from the roots to the tea leaves. This is thought to be because the production of catechins is suppressed because the biosynthesis of is difficult to proceed.
Thereby, the accumulation amount of the umami component in the tea leaf can be increased while suppressing the production of the astringent component.

On the other hand, nighttime supplementary light can increase the umami component without extending the period of light-shielded cultivation, so that an increase in stress on the tea plant can be suppressed as much as possible.
Moreover, the supplementary light at night can be easily applied to the cultivation of tea trees that are not subjected to light-shading cultivation.

(2) The tea tree cultivation method according to the present invention is characterized in that the light irradiation to the tea tree is carried out at an appropriate time zone at night as necessary.
In the tea tree cultivation method of the present invention, the light irradiation to the tea tree is performed at appropriate times during the night.
This makes it possible to further increase the content of free amino acids as umami components while further suppressing the content of catechins as astringency components, compared to the case where light supplementation is performed overnight.

(3) The tea tree cultivation method according to the present invention is characterized in that the time period is from an appropriate time after midnight to an appropriate time before sunrise time, as necessary.
In the tea tree cultivation method of the present invention, light supplement to the tea tree is performed in a time zone from an appropriate time after midnight to an appropriate time before sunrise time.

  The tea tree that performs photosynthesis is activated dramatically by irradiation of the morning sun, but it can be pre-activated by supplementing light at an appropriate time zone in the early morning before sunrise, As a result, the content of free amino acids, which are umami components, can be further increased.

(4) The tea plant cultivation method according to the present invention is characterized in that the time period is from an appropriate time before midnight to an appropriate time after midnight.
In the tea tree cultivation method of the present invention, light supplement to the tea tree is performed during a time period from an appropriate time before midnight to an appropriate time after midnight. In other words, the light supplement to the tea tree is performed at an appropriate time zone between midnight and midnight.

  As described above, the biological activity of the tea tree was reduced once by passing the night appropriately, and then the tea tree was supplemented to activate the tea tree, so that the biosynthesis activity to catechins was sufficiently reduced. The light is supplemented in the state, and the content of free amino acids as umami components can be further increased while further suppressing the content of catechins as astringent components.

(5) The tea tree cultivation method according to the present invention is characterized by intermittently irradiating the tea tree with light as necessary.
In the tea tree cultivation method of the present invention, light irradiation to the tea tree is performed intermittently. This may be an intermittent implementation in which both the supplementary light period and the supplementary light stop period are set to a fixed time and alternately performed. Alternatively, the supplementary light period and the supplementary light stop period are set to indefinite times. Alternatively, the operations may be performed alternately. Such a supplementary light stop period may be a time during which the biosynthetic activity to catechins is sufficiently reduced.

  By intermittently supplementing the tea plant in this way, the activation of the tea plant is made intermittently, thereby further reducing the content of catechins which are astringent components, while free amino acids which are umami components The content can be further increased.

(6) The tea tree cultivation method according to the present invention is characterized by irradiating with light so that the average illuminance on the crown surface of the tea tree is 50 lx, if necessary.
In the tea tree cultivation method of the present invention, light is irradiated so that the average illuminance on the crown surface of the tea tree is 50 lx.

  As a result of intensive studies by the present inventors, when performing supplementary light in the time zone from the appropriate time after midnight to the appropriate time before sunrise, or when intermittently supplementing, The content of free amino acids could be further increased by irradiating light so that the average illuminance at the crown surface of the tea tree was 50 lx.

(7) The tea tree cultivation method according to the present invention is characterized by irradiating light so that the average illuminance on the crown surface of the tea tree is 80 lx, as necessary.
In the tea tree cultivation method of the present invention, light is irradiated so that the average illuminance on the crown surface of the tea tree is 80 lx.

  As a result of intensive studies by the present inventors, when supplementary light is performed in a time zone from an appropriate time before midnight to an appropriate time after midnight, the light is adjusted so that the average illuminance at the crown of the tea tree is 80 lx. The content of free amino acids could be further increased by irradiating with.

  (8) A tea tree cultivation apparatus according to the present invention is an apparatus for cultivating a tea tree for harvesting tea leaves, and irradiates the tea tree with light having an appropriate illuminance with an average illuminance at a crown surface of the tea tree of 100 lx or less. And a power supply unit that supplies power to the projector, and a control unit that controls power supply to the projector of the power supply unit. The control unit causes the power supply unit to supply power to the projector at night. It is characterized by being.

  In the tea tree cultivation apparatus of the present invention, to a tea tree, a projector that irradiates light with an appropriate illuminance with an average illuminance on the crown surface of the tea tree of 100 lx or less, a power supply unit that supplies power to the projector, and a projector of the power supply unit And a control unit that controls the power supply of the power supply. The control unit causes the power supply unit to supply power to the projector at night.

  As the projector, a fluorescent lamp, an incandescent lamp, an LED, or the like can be used. Power is supplied to the projector from the power supply unit, and power supply from the power supply unit to the projector is controlled by the control unit. In other words, the control unit causes the power supply unit to supply power to the projector at night. Although power supply at night can be performed all night, as described above, it is preferable to perform power supply at an appropriate time during the night.

Specifically, the control unit serves as a power source to supply power to the projector from an appropriate time after midnight to an appropriate time before sunrise, or from an appropriate time before midnight to an appropriate time after midnight. To do.
Moreover, a control part may be made to supply electric power to a projector by making it a power supply part, and may supply electric power intermittently.
This makes it possible to further increase the content of free amino acids as umami components while further suppressing the content of catechins as astringent components, as before.

It is a typical perspective view which shows the state which is cultivating a tea tree using the tea tree cultivation apparatus which concerns on this invention. It is a typical perspective view which shows the state which is growing the tea tree using the tea tree cultivation apparatus which concerns on other embodiment. It is a histogram which shows the result of having compared the free amino acid content of the tea leaf when supplementary light cultivation is performed, and the free amino acid content of the tea leaf when not performing supplementary light cultivation. It is a histogram which shows the result of having compared the catechin content of the tea leaf when supplementary light cultivation is performed and the catechin content of the tea leaf when supplementary light cultivation is not performed. It is a histogram which shows the result of having performed supplementary light cultivation using the light source of a different color.

(First embodiment)
FIG. 1 is a schematic perspective view showing a state in which a tea tree is cultivated using the tea tree cultivation apparatus according to the present invention, in which C is a tea tree. A plurality of tea trees C, C,... Are grown in a linear shape, and around each tea tree C, C,... , ... are placed at an appropriate distance from each other. The light shielding shelf 30 is detachably attached with a light shielding member 31 that covers the ceiling and the periphery of the light shielding shelf 30, and the light shielding member 31 blocks external light so as to have an appropriate incident rate. . As the light shielding member 31, a net made of a synthetic resin, a bag, a bag, or the like can be used alone or in combination.

A plurality of projectors 5, 5,... Using a light source such as a fluorescent lamp or an incandescent lamp are arranged at the ceiling position inside the light shielding member 31, and the tea plants C, C,. ... Can be projected so that the average illuminance is 100 lx or less on the crown surface F of the tea trees C, C,. The projectors 5, 5,... May irradiate the tea trees C, C,... With light of the wavelength using a film that transmits light of a required wavelength such as blue or red.
The projectors 5, 5,... Are supplied with power from the power supply unit 2 of the power feeder 1, and the power feeder 1 has a control unit 3 that controls power supply to the projectors 5, 5,. It is provided.

Next, a method for cultivating tea trees using such an apparatus will be described.
In the tea tree cultivation method according to the present invention, so-called light supplementation is performed in which the tea tree is supplemented with light by irradiating the tea tree with weak light at night during the shoot growth stage of the tea tree.

  Such supplemental light is performed by irradiating light with an appropriate illuminance of 100 lx or less on the average at the crown surface F formed at the tips of the plurality of branches constituting the tea tree. The illuminance is, for example, LI-1400, PHOTOMETRIC, SR. Measurement is performed using an illuminometer such as NO PH7337 (manufactured by LI-COR).

  In addition, supplementary light can be performed continuously throughout the night, but can also be performed intermittently throughout the night, and can also be performed at an appropriate time zone at night, such as an appropriate time zone before sunrise or an appropriate time zone at midnight. it can.

  In the case where supplementary light is continuously implemented overnight, an illuminance detection unit for detecting ambient illuminance is provided in the power feeder 1 in advance, and the control unit 3 detects the ambient light detected by the illuminance detection unit. When the illuminance of light falls below the illuminance to be supplemented, power supply from the power supply unit 2 to the projectors 5, 5,... Is started, and the illuminance of ambient light detected by the illuminance detector exceeds the illuminance to supplement The power supply from the power supply unit 2 to the projectors 5, 5,... Is stopped.

  In addition, in the case where supplementary light is intermittently implemented overnight, the control unit 3 causes the projector 5 to emit light from the power supply unit 2 when the illuminance of the ambient light detected by the illuminance detection unit is less than or equal to the illuminance to be supplemented. , 5,... Is started. In addition, the feeder 1 is provided with timing means in advance, and the control unit 3 causes the power supply unit 2 to turn off the power supply, for example, 10 minutes after starting the feeding based on the timing information given from the timing means. The operation of turning on the power supply is repeated 50 minutes after turning off the power. When the illuminance of the ambient light detected by the illuminance detection unit exceeds the supplemented illuminance, the control unit 3 stops power supply from the power supply unit 2 to the projectors 5, 5,. Note that the time (10 minutes) until the power supply is turned off and the time (50 minutes) until the power supply is turned on can be set as appropriate.

  On the other hand, in the case of performing supplementary light at an appropriate time zone at night, the control unit 3 sends the illuminance to the power source unit 2 based on the detection result of the illuminance detection unit and the timing information given from the timing unit. After the illuminance of the ambient light detected by the detection unit becomes less than or equal to the illuminance to be supplemented, for example, after 5 hours have elapsed, power supply from the power supply unit 2 to the projectors 5, 5,. Power supply is terminated after 4 hours from the time. As a result, the light can be supplemented in several hours before and after midnight.

  Furthermore, in the case of performing supplementary light at an appropriate time zone before sunrise, the sunrise time is preset in the control unit 3 according to the calendar, and the control unit 3 Based on the timing information provided by the means, power supply from the power supply unit 2 to the projectors 5, 5,... Is started from 1 hour to 4 hours before the sunrise time of the day, and the power supply is performed near the sunrise time of the day. It is supposed to be stopped.

Here, the average illuminance of the light irradiated to the tea plants C, C,... By supplying power to the projectors 5, 5,... May be an appropriate illuminance of 100 lx or less as described above. 50 lx is preferable for implementing the above, and about 50 lx is suitable for performing supplementary light in an appropriate time zone before sunrise, and is compensated for in an appropriate time zone at night other than before sunrise. In the case of implementing light, about 80 lx is preferable.
Such a light supplement operation at night is appropriately performed for the number of days during the shoot growth period of the tea plant. In addition, according to the first tea, the second tea, and the third tea, a night light supplement operation is performed.

  In this way, by supplementing the tea plant at night, the accumulation amount of free amino acids including theanine can be increased while suppressing the production of catechins.

By illuminating the tea plant with light at night, the tea plant that performs photosynthesis can be activated, and theanine can be transferred from the root to the tea leaf. It is thought that this is because the production of catechins is suppressed because it does not proceed easily.
Thereby, the accumulation amount of the umami component in the tea leaf can be increased while suppressing the production of the astringent component.

  Therefore, when the shaded cultivation days are the same as when the supplementary light cultivation is not performed, the accumulated amount of umami components contained in the harvested tea leaves can be further increased, while the accumulated amount of umami components contained in the tea leaves When the tea leaves are harvested at the same timing as when no supplementary light cultivation is carried out, the light shielding period can be shortened. In the latter case, the stress applied to the tea tree by shading cultivation can be reduced, so that the vitality of the tea tree can be increased.

On the other hand, since the supplementary light operation is performed by the control unit 3 of the power feeder 1 as described above, supplementary light cultivation can be easily performed regardless of the manual operation. Needless to say, the above-described light supplementing operation may be performed by an administrator without depending on the control unit 3 of the power feeder 1.
Moreover, the vitality of a tea tree can also be assisted by supplementing the tea tree cultivated by shading at night.

(Other embodiments)
FIG. 2 is a schematic perspective view showing a state where a tea tree is cultivated using a tea tree cultivation apparatus according to another embodiment, and shows a case where an LED (Light Emitting Diode) is used as a light source. In the figure, parts corresponding to those shown in FIG.

  As shown in FIG. 2, string-shaped projectors 5 a, 5 a formed by arranging a plurality of LEDs in a linear shape inside the light shielding member 31, for example, are placed at appropriate positions on both sides of the light shielding shelf 30. It is attached so that light may be applied to the tea plants C, C,... From obliquely above C, C,.

The LED that is a light source of the projectors 5a and 5a is attached with an LED that emits light of an appropriate wavelength, but preferably an LED that emits blue light, red light, or yellow light is attached.
Then, light can be projected from the projectors 5a, 5a to the tea trees C, C,... So that the average illuminance is 100 lx or less on the crown surface F of the tea trees C, C,.

  In order to cultivate a tea tree using such a tea tree cultivating apparatus, it is carried out by performing supplementary light that irradiates light with an appropriate illuminance of an average of 100 lx or less on the crown surface F of the tea tree at night as before.

Such supplementary light can be performed continuously all night, but can also be performed all night, and can also be performed at an appropriate time zone at night, such as an appropriate time zone before sunrise or an appropriate time zone at midnight. .
In this way, by supplementing the tea plant at night, the accumulation amount of free amino acids including theanine can be increased while suppressing the production of catechins.

In both of the above-described embodiments, the light shielding member 31 is installed to be applied to tea tree cultivation for undercover tea. However, the present invention is not limited to this, and is used for sencha without the light shielding member 31 installed. It can be applied to the cultivation of tea trees. In this case, a support member that supports the projectors 5, 5,... (5a, 5a,...) Is installed at an appropriate location in the tea garden, and the projectors 5, 5,. ...) is used to supplement the tea plant at night.
As a result, the amount of accumulated theanine can be increased while suppressing the production of catechins, and the quality of sencha can be improved as before.

  In the present embodiment, the projectors 5a and 5a are attached to appropriate positions on both sides of the light shielding shelf 30 so as to irradiate the tea trees C, C,... Although shown about the case, this invention is not restricted to this, A plurality of floodlights 5a, 5a,... Are arranged in the ceiling region of the light shielding shelf 30, and the tea trees C, C,. Further, one or a plurality of light projectors 5a (5a,...) May be applied to the side of the light shielding shelf 30 from the side of the tea trees C, C,. ,... May be attached so as to emit light.

Example 1
Next, the results of carrying out the tea tree cultivation method according to the present invention will be described.
FIG. 3 is a histogram showing the results of comparing the free amino acid content of tea leaves when supplementary light cultivation is performed with the free amino acid contents of tea leaves when supplementary light cultivation is not performed. Indicates the mass of free amino acids contained in 100 g of dried tea leaves. Moreover, in FIG. 3, A has shown the case where supplementary light cultivation is performed, and B has each shown the case where supplementary light cultivation is not performed. For reference, a test in which light having the same illuminance as that of the day was irradiated for 24 hours was also conducted.

  Moreover, FIG. 4 is a histogram showing the results of comparing the catechin content of tea leaves when supplemented light cultivation and the catechin contents of tea leaves when not supplemented light cultivation, The vertical axis represents the mass of catechins contained in 100 g of dried tea leaves. Moreover, in FIG. 4, A has shown the case where supplementary light cultivation is performed, and B has each shown the case where supplementary light cultivation is not performed. The reference result was C as before.

  In an artificial environment laboratory adjusted to 23 ° C to 20 ° C, 14 hours from 6:00 am to 8:00 pm are daylighted with illuminance of 5000 lx, while 10 hours from 8:00 pm to 6 am The tea plant grown for 17 days from the day when the first foliage of secondary side buds developed in this environment was designated as B.

On the other hand, supplementary light cultivation is supplemented for 3 hours from 3 am to 6 am before sunrise in A-1 and from 11 pm to 2 am in A-2 For 3 hours, and for A-3, light is emitted intermittently by repeating the operation of turning off the light for 50 minutes after projecting for 10 hours from 8 pm to 6 am A-4 was performed under the same conditions as B described above except that A-4 was continuously supplemented all night from 8 pm to 6 am.
The supplementary light was performed so that the illuminance on the surface of the tea plant was 80 lx (photon amount: 1.7 μmolm ⁻² s ⁻¹ ).

  As apparent from FIG. 3, in supplementary light cultivation in which nighttime supplementation is performed, the free amino acid content of tea leaves increases in the case of A-1 to A-4 in the case of B which does not perform nighttime supplementation. Was.

  Further, as is clear from FIG. 4, the catechins content of tea leaves was lower than that in the case of B where no nighttime supplementation was performed in any of A-1 to A-3, but continued all night. In the case of A-4 where the supplementary light was applied, the value was slightly higher than in the case of B where the supplementary light was not performed at night.

(Example 2)
Next, a description will be given of the results of testing with different supplemental illumination intensity for supplementary cultivation of A-1 to A-3 in which the content of free amino acids in tea leaves is increased as compared with the case where no supplementation is performed at night.
The supplementary light test was conducted in Saga City, Saga Prefecture for 14 days from September 17, 2007, when the first leaf of the secondary side buds developed. Auxiliary light in each light supplement cultivation of A-3 from A-1, the average illuminance on the crown surface 80Lx (photon ^{weight: 1.7μmolm -2 s -1), 50lx} ( photons weight: 1.1μmolm ^-2 s ^-1 ), 20 lx (photon amount: 0.45 μmolm ⁻² s ⁻¹ ).

  In addition, supplementary light cultivation is supplemented for 3 hours from 3 am to 6 am in A-1 and 3 from 11 pm to 2 am in A-2. Complementary light is supplied continuously, and for A-3, light is projected for 12 hours from 7 pm to 7 am for 10 minutes and then turned off for 50 minutes. Went light.

In addition, the case where light-shielding cultivation was performed but supplementary light cultivation was not performed was set as a control, and the case where light-shielding cultivation was not performed was also referred to.
The following table shows the results of testing at different supplemental illumination intensity.

  As is clear from the table, in A-1, which performs supplementary light for 3 hours continuously from 3:00 am to 6:00 am, when the illuminance is 50 lx, the free amino acid content is the highest, and catechin Was the least.

In addition, in A-2 which performs supplementary light for 3 hours continuously from 11:00 pm to 2:00 am, when the illuminance is 80 lx, the content of free amino acids is the highest, and the content of catechins Was the least.
On the other hand, in A-3 that performs supplementary light that is intermittently projected for 12 hours from 7:00 pm to 7:00 am, the free amino acid content was the highest when the illuminance was 50 lx.

Example 3
Next, the result of having examined the influence of the light wavelength in supplementary light cultivation is demonstrated.
FIG. 5 is a histogram showing the results of supplementary light cultivation using light sources of different colors. In the figure, the vertical axis represents the mass of free amino acids contained in 100 g of dried tea leaves.

Further, in FIG. 5, B is a case where blue light is irradiated, G is a case where green light is irradiated, Y is a case where yellow light is irradiated, O is a case where orange light is irradiated, R indicates a case where red light is irradiated.
As is clear from FIG. 5, the mass of free amino acids contained in the tea leaves was the highest when irradiated with blue light, followed by the cases when irradiated with red light and yellow light in this order.

DESCRIPTION OF SYMBOLS 1 Power feeder 2 Power supply part 3 Control part 5 Light projector 5a Light projector 30 Light shielding shelf 31 Light shielding member C Tea tree F Tree crown

Claims (8)

In the method of cultivating tea trees for harvesting tea leaves,
A method for cultivating tea trees, wherein the tea tree is irradiated with light having an appropriate illuminance with an average illuminance of 100 lx or less on the crown surface of the tea tree at night during the shoot growth period of the tea tree.   The tea tree cultivation method according to claim 1, wherein the tea tree is irradiated with light in an appropriate time zone at night.   The tea plant cultivation method according to claim 2, wherein the time period is from an appropriate time after midnight to an appropriate time before sunrise.   The tea plant cultivation method according to claim 2, wherein the time period is from an appropriate time before midnight to an appropriate time after midnight.   The method for cultivating tea trees according to claim 1, wherein the irradiation of light to the tea trees is carried out intermittently.   The tea tree cultivation method according to claim 3 or 5, wherein light is irradiated so that an average illuminance on the crown surface of the tea tree is 50 lx.   The tea tree cultivation method of Claim 4 which irradiates light so that the average illumination intensity in the crown surface of the said tea tree may be set to 80 lx. An apparatus for cultivating tea plants for harvesting tea leaves,
A projector that irradiates the tea tree with light having an appropriate illuminance of 100 lx or less on the average illuminance on the crown of the tea tree;
A power supply for supplying power to the projector;
A control unit that controls power supply to the projector of the power supply unit,
The tea plant cultivation apparatus, wherein the control unit causes the power supply unit to supply power to the projector at night.

Images