WO2012102372A1 - Plant cultivation method and plant cultivation device - Google Patents

Abstract

[Problem] To provide a plant cultivation device, by which a plant can be efficiently cultivated using the circadian rhythms of the plant inherent thereto, and a method therefor. [Solution] A plant cultivation device comprising: a housing (11) having a cultivation space (13) in which a plant is to be enclosed; a light source (12) which is provided in the upper part of the housing (11) for emitting cultivation light required for the growth of the plant, said plant being enclosed in the cultivation space (13); a light source controller (21) for switching the light source (12); a computer (20) for controlling the light source controller (21); a keyboard (30) which is an input means for setting light-dark cycles; a memory unit (22) which is a storage means for storing the light-dark cycles having been set by using the keyboard (30); and a display (40) which is an indication means for indicating temperature and humidity in the cultivation space (13). In the aforesaid device, for example, the light period is set to 11 hours and the dark period is set to 11 hours. Then, the switching of the light source (12) is controlled so that the dark period is terminated 1 to 3 hours before the dawn in the circadian rhythms of the plant.

Description

Plant cultivation method and plant cultivation apparatus

The present invention relates to a plant cultivation method and a plant cultivation apparatus.

A plant cultivation apparatus for growing plants such as crops and agricultural products by artificially controlling elements necessary for plant cultivation such as light, temperature, humidity, water, and nutrients is known. This device is also known as a plant factory that efficiently industrializes from sowing for producing agricultural products to harvesting and shipping. Since this device is not affected by the natural environment, it enables stable crop production in barren areas such as cold regions and deserts. Moreover, it does not require farmland unlike conventional farming methods, and enables plant production in facilities such as buildings and large ships.

For example, as a recent new plant utilization, technical development aimed at producing useful substances such as high-value-added proteins used in medicine etc. in plants and using them as feed for livestock, etc., or extraction and purification Has attracted attention (see Non-Patent Document 1). Since plant chloroplasts are excellent places for storing foreign proteins at high density, there are examples of cultivating leafy plants such as lettuce in which foreign protein genes are introduced into the chloroplast genome in a closed plant factory.

Plant cultivation devices have the advantage that environmental control and cultivation process changes are relatively easy. Therefore, when growing edible vegetables and ornamental plants in plant cultivation equipment, observe the appearance of the shape and size of the leaves, stems, etc. Implement and cultivate in a cleaner shape and desired size.

In an advanced plant cultivation device, after diagnosing the growth state by a computer from a captured image of a plant body by a camera, control such as feedback from the obtained diagnostic information or selection etc. However, the essence of controlling the growth environment and process using the appearance information of the plant body was the same.

As such an advanced plant cultivation apparatus, for example, in Patent Document 1, a projector that projects seedling light for raising a plurality of seedlings, a CCD camera that acquires a seedling image obtained by imaging a plurality of seedlings, A growth state determination unit that determines the growth state of each of the plurality of seedlings based on the seedling image, and a seedling that is suitable for the growth of each of the plurality of seedlings based on the growth state of each of the plurality of seedlings determined by the growth state determination unit A plant cultivating apparatus including a projection condition setting unit that sets a projection area and projection conditions of light is described.

In plant cultivation equipment, how to control the above elements for efficient crop production is an important issue. Among them, optimization technology for plant environmental response, in particular, photosynthesis and photoenvironmental response, is one of the important technical needs to bring about dramatic improvement in functions of agricultural, forestry and fishery products. For example, Patent Document 2 includes a light control unit, a temperature control unit, a humidity control unit, and the like configured by a plurality of light emitting elements that emit light having different wavelengths, and inputs the target plant growth conditions. A plant cultivation apparatus that controls the irradiation start time, irradiation amount, and irradiation time when irradiating light having a wavelength suitable for the plant has been proposed. Further, Patent Literature 3 proposes a plant cultivation apparatus that irradiates far red light and controls the photoperiodic reaction so that the ratio of far red light and red light is equal to or greater than a predetermined value. In these plant cultivation apparatuses, for example, the illumination lighting schedule is conventionally set to a light / dark cycle of 24 hours as described in Patent Document 2, or short-day cultivation as described in Patent Document 3 As a matter of experience, the period of shortening the sunshine hours has been established.

By the way, many organisms have a circadian rhythm (circadian rhythm), and a substance metabolism cycle in a plant including photosynthesis is regulated by a biological clock of the plant. The circadian rhythm has a period of about one day, and regularly operates a substance metabolism cycle in about 24 hours. The circadian rhythm (circadian rhythm) is designed so that the substance metabolism cycle works most efficiently under the day-night cycle. Further, it is well known that the circadian rhythm is influenced by light, and the circadian rhythm is influenced by stimulation of a dark pulse (dark pulse) or a light pulse (light pulse). For example, in plants, the efficiency of photosynthesis increases from morning to daytime, and the metabolic efficiency of sugar transport increases at night. This circadian circadian rhythm is generated spontaneously by the body clock even when the external environmental conditions are constant and there is no factor to inform the time.

As described in Non-Patent Document 2 and Non-Patent Document 3, the circadian rhythm mechanism is being elucidated from the individual level to the gene level from a more microscopic viewpoint. Is moving forward.

By the way, Non-Patent Document 4 describes that a mutant strain with a short circadian rhythm (cycle: 20.7 hours), a mutant strain with a long cycle (cycle: 27.1-32.5 hours), a wild strain (cycle: about 24 hours). ) Under the light-dark cycle of 20 hours, 24 hours, and 28 hours, respectively (equal time of light and dark). Production and plant growth have been reported to be optimal. Therefore, it is expected that the plant can be cultivated under the optimum conditions for the plant by controlling the lighting with the light / dark cycle in accordance with the cycle of the circadian rhythm of the plant to be cultivated (the circadian resonance method).

In addition, it is known that the biological clock regulates the expression timing of about 10% of genes in the entire genome including the photosynthetic genes and cell elongation genes, thereby adjusting the metabolic balance. Thus, genetic engineering modification of the clock gene, which is the main gene of the body clock, can be expected to extend the plant growth period and delay flowering. For example, Patent Document 4 changes the flowering time of plants by binding to the promoter region of the Arabidopsis thaliana chlorophyll-binding protein gene (Lhcbl * 3) and regulating the expression of a phytochrome-regulated transcription factor named CCA1. A method is described.

Under such circumstances, Non-Patent Document 1 discloses that the expression cycle of the clock gene ( CCA1 ), that is, the circadian rhythm is controlled by changing the light-dark cycle, and the light-dark cycle and the circadian rhythm can be completely synchronized. It has been simulated. Non-Patent Document 5 describes that circadian rhythm is controlled by the light-dark cycle using Arabidopsis thaliana introduced with a luciferase gene as a clock gene expression reporter. Further, Non-Patent Document 5 simulated that the circadian rhythm disappears under continuous irradiation light, and that the lost circadian rhythm regains the circadian rhythm by stimulation with a dark pulse. It is described that this circadian rhythm is correctly reconstructed in Arabidopsis thaliana introduced with a luciferase gene as an expression reporter. For example, when Arabidopsis thaliana that has lost its circadian rhythm by continuous irradiation is given a 2-hour dark period (dark pulse) in a 23-hour cycle, a 23-hour circadian rhythm is observed (pulling effect).

JP 2004-121033 A Japanese Patent Laid-Open No. 10-178899 JP 2009-136155 A Japanese translation of PCT publication No. 2002-501381

When cultivated under constant continuous light conditions, etc., ignoring the work of the body clock, abnormalities occur in crop growth and morphogenesis. For these reasons, metabolic cycle optimization technology focusing on biological clocks is one of the most important technical needs in closed plant factories that produce artificial day / night cycles.

The lighting control in the conventional cultivation method is a method in which the light / dark cycle is set to 24 hours as described in Patent Document 2, and the light period and dark period are adjusted within 24 hours. In addition, short-day cultivation as described in Patent Document 3 is a cultivation method in which a period of time for temporarily stimulating by shortening the sunshine time is provided, but this cultivation method is also controlled with a light / dark cycle of 24 hours. Yes. In addition, the circadian resonance method is known as a cultivation method that takes into account the circadian rhythm of the plant. This method is a cultivation method that matches the light-dark cycle with the circadian rhythm inherent in the plant. The light / dark cycle is determined so that the length and the length of the dark period are equal.

However, when the cultivating light is controlled with a light / dark cycle in which the length of the light period is equal to the length of the dark period, the temperature difference between the light period and the dark period may increase with a change in the amount of heat generated from the light source. For this reason, it must be managed so as to reduce the temperature difference between the light and dark periods in the cultivation room, and there is a problem that high processing capacity of the air conditioner required for temperature management and excessive power consumption associated therewith are generated.

On the other hand, when cultivating crops under continuous lighting, temperature management is simplified, and the load on the control of lighting equipment and air conditioning equipment is reduced. In addition, since the total amount of photosynthesis performed by the crop is almost proportional to the total amount of light irradiated, there is a possibility that the period from the start of cultivation to the harvest can be shortened by continuous illumination. However, continuous lighting attenuates the circadian rhythm and causes poor growth. That is, since continuous illumination normally irradiates twice as much light in the same cultivation period as in bright and dark illumination, the amount of photosynthesis is nearly twice as much in continuous illumination in the same cultivation period. And quality such as shape and color are degraded by continuous lighting. Thus, even under continuous lighting, it cannot be said that it is optimal when considering the quality of crops and the growth amount (cost performance) per dropped energy.

As mentioned above, conventional lighting control cannot be said to be optimal in terms of the load on the air conditioner and the amount of crop growth per unit of energy (cost performance). There is a need for an efficient and optimal cultivation method that takes into account the physiological metabolism of crops and crops.

In addition, the method of imaging the appearance of the plant with a camera, diagnosing the growth state by image processing, etc., and performing environmental control and selection of the plant based on the information, images the leaves, stems, buds, etc. of the plant Since environmental control, selection, and the like are performed, seedlings in the seedling raising period (about several weeks after sowing) have a small amount of appearance information of the plant body as a determination material, and precise determination is difficult.

Furthermore, when producing useful substances such as high-value-added proteins used in medicine in plants, the appearance of the plant is imaged with a camera, the growth state is diagnosed by image processing, etc., and environmental control is performed based on the information. In the method of performing or selecting plants, appearance information such as whether the plant looks beautiful or whether the plant is large has an absolute meaning on the productivity of useful substances. Therefore, there has been a problem that optimization control and selection of the growth conditions of the plant body that produces useful substances cannot be performed.

The present invention has been made based on the above-mentioned background art, and an object thereof is to provide a plant cultivation apparatus that enables more efficient cultivation based on research on circadian rhythms unique to plants.

Another object of the present invention is to provide a technique that makes it possible to determine the growth state of a plant based on information other than the appearance information of the plant, and to perform plant selection and environmental control with high accuracy. To do.

The inventors of the present application further researched based on the knowledge that a dark pulse due to a short dark period can adjust the circadian rhythm of the plant. When the dark period or the light period is set according to a specific algorithm, the plant cultivation apparatus As a result, the present invention was completed.

That is, the present invention is a cultivation light control method for cultivating a plant by irradiating cultivation light under an artificially controlled light and dark cycle, wherein the light and dark cycle is a light period in which cultivation light is irradiated and The cultivation light having a light quantity less than the light quantity in the light period is irradiated or has a dark period without the light quantity, and the cycle of the light-dark cycle is a cycle different from the inherent free-run cycle of the plant. The cultivation light control method in which the dark period is set to a time zone with low photosynthetic activity or the light period is set to a time zone with high photosynthetic activity is provided.

In addition, the present invention diagnoses the growth state of a plant based on the bioluminescence of a modified plant so that the expression level of an endogenous gene whose expression increases as the plant grows can be identified by bioluminescence. A molecular projection method for projecting light for cultivating a luminescent gene-introduced plant into which a luminescent gene has been introduced, and an expression of an endogenous gene that has increased with the growth of the luminescent gene-introduced plant A luminescence image acquisition step of capturing a luminescence image by imaging the amount as bioluminescence, and a growth state diagnosis step of diagnosing the growth state of the luminescent gene-introduced plant based on the luminescence amount of bioluminescence in the luminescence image A molecular diagnostic method is provided.

According to the present invention, the dark period is set in a time zone where photosynthesis activity is low, or the light period is set in a time zone where photosynthesis activity is high. For example, the cycle of the light-dark cycle is shorter than the plant-specific free run cycle observed under continuous illumination, and the end of the dark cycle is set 1 to 3 hours before the dawn time in the circadian rhythm of the plant Can be achieved. By setting the dark period in the time zone where photosynthesis activity is low, the total amount of photosynthesis increases compared to the case of cultivating at the same irradiation time, thereby shortening the cultivation period until it becomes a size that can be shipped, Cost performance per dropped energy can be increased.

Also, under almost continuous illumination, the dark period can be set to a period with low photosynthetic activity, or the light period can be set to a period with high photosynthetic activity. When the dark period is set to a period with low photosynthetic activity, not only the growth rate of plants per day under continuous lighting is increased, but also unnecessary lighting in a period when light utilization is poor is prevented. As a result, the power consumption is reduced as compared with the case of continuous lighting with the same brightness. On the other hand, if the light period is set to a period when the photosynthetic activity is high, the amount of light can be suppressed when the photosynthetic activity is relatively low, and the amount of light can be increased per day by increasing the amount of light when the photosynthetic activity is high. Utilization efficiency of cultivation light can be increased. In any case, the loss of circadian rhythm due to continuous irradiation is prevented, and plant growth under continuous illumination is well maintained.

According to the molecular diagnostic method of the present invention, diagnosis of the growth state of a plant body based on the expression level of the endogenous gene enables diagnosis with higher accuracy than when diagnosing the growth state of the plant body based on appearance information. can do. That is, since the endogenous gene expression in the plant body and the growth of the plant body are correlated, it becomes possible to diagnose the growth state of the plant body at the molecular level based on the strength of the expression of the endogenous gene, Even at an early stage such as the seedling raising period, it is possible to select excellent seedlings and estimate the expression level of useful proteins. Further, the metabolic cycle of a plant can be estimated from the expression level of the endogenous gene, and environmental control most suitable for the plant body can be achieved at the molecular level.

FIG. 1 is a conceptual diagram showing a cultivation light control method according to one embodiment of the present invention. FIG. 2 is a diagram showing the phase shift of the circadian rhythm when a single dark pulse is given under continuous illumination. FIG. 3 is a diagram showing an example of a phase response curve when a dark pulse of 2 hours is given. FIG. 4 is a diagram illustrating an example of a phase response curve when a 2-hour write pulse is applied. FIG. 5 is a conceptual diagram showing a cultivation method provided with a light-dark cycle adjustment period. FIG. 6 is a schematic diagram of a plant cultivation apparatus according to an embodiment of the present invention. FIG. 7 is a schematic view of a plant cultivation apparatus according to another embodiment of the present invention. FIG. 8 is a graph showing the light quality dependence of the circadian rhythm. FIG. 9 is a diagram showing the influence of the difference in light and dark cycle on the growth of plants, and the influence on the growth rate r (raw weight increase rate per day) and cultivation efficiency q (fresh weight increase rate per lighting time). Show. FIG. 10 is a diagram showing the effect of light / dark cycle differences on plant growth, and shows the effect on the above-ground weight (mg) and root ratio (%). FIG. 11 is a diagram showing the effect of light / dark cycle differences on plant growth, and shows the effect on dry weight (mg) and moisture content (%). FIG. 12 is a diagram showing the effect of light / dark cycle differences on plant growth, and shows the effect on the amount of chlorophyll (μg Chl / raw weight mg). FIG. 13 is a diagram showing an outline of a molecular diagnostic plant cultivation apparatus equipped with a molecular diagnostic system. FIG. 14 is a diagram for explaining the configuration of the molecular diagnostic system in the early diagnosis stage B. FIG. 15 is a flowchart showing the molecular diagnosis process of the molecular diagnosis system in the early diagnosis stage B. FIG. 16 is a diagram illustrating an example of data in which the correction algorithm is set in the coordinate information (x _n , y _n ) of the nursery pallet. FIG. 17 is a diagram showing an example of a luminescent image of a seedling photographed by the luminescent image acquisition means and diagnostic result data of the growth state thereof. FIG. 18 is a correlation diagram between the dry weight after cultivation and the leaf area of the seedling, and the dry weight after cultivation and the amount of luminescence of the seedling. FIG. 19 is a diagram showing the correlation between the total amount of bioluminescence generated and the leaf area of seedlings, and the total amount of bioluminescence generated and the amount of luminescence of seedlings. FIG. 20 is a diagram for explaining the configuration of the molecular diagnostic system in the cultivation stage C. FIG. 21 is a flowchart showing the molecular diagnosis process of the molecular diagnosis system in the cultivation stage C. FIG. 22 is a diagram showing an example of circadian rhythm information created based on the measurement value of the light emission amount. FIG. 23 is an example of expression information of a photosynthesis-related gene (chlorophyll AB-binding protein gene CAB) created based on the measured value of luminescence.

The cultivation light control method of the present invention is a method for controlling cultivation light in a light / dark cycle in which the dark period is set to a time zone with low photosynthetic activity or the light period is set to a time zone with high photosynthesis activity.

In this specification, “free-run cycle” means a cycle in the circadian rhythm observed under continuous illumination conditions or continuous dark conditions. “Circadian rhythm”, also called circadian rhythm, means an increase or decrease in the expression level of a specific gene (group) in a plant that is observed in a cycle of approximately 24 hours, and various physiological phenomena that occur as a result. This physiological phenomenon is observed as a substance metabolism activity (indicator) in the plant body controlled by a clock gene. The metabolic activity of plants is metabolic activity such as sugar metabolism and cell proliferation, and is a result of enhancement / suppression of the expression of photosynthetic genes, sugar metabolism genes or cell proliferation genes. “Circadian rhythm” is the daily rhythm observed in any of these metabolic activities. The circadian rhythm used for optimizing plant growth is preferably a circadian rhythm with respect to metabolic activity that serves as an index of plant growth, and examples thereof include photosynthetic activity and sugar metabolism. The circadian rhythm may be based on one metabolic activity, or may be an index considering a plurality of metabolic activities. Here, the optimization of plant growth means maximizing the production amount per dropped energy (cost performance) or the production amount per production period (production rate). The production amount here means the growth amount (raw weight or dry weight) or the production amount of useful substances such as nutritional components and pharmaceutical proteins.

For example, as described in Non-Patent Document 1, the circadian rhythm is obtained by incorporating a luciferase structural gene downstream of the promoter region of a gene encoding a gene involved in photosynthesis or growth or a useful protein. Known methods such as a method for determining the amount of luciferase luminescence by continuously measuring the amount of circadian rhythm by measuring a fixed amount of carbon dioxide gas as described in Non-Patent Document 4. It is calculated by. The calculated circadian rhythm is expressed as the time variation of metabolic activity. Moreover, it can also obtain | require using the molecular diagnostic type plant cultivation apparatus demonstrated below.

In this specification, “free-run cycle” means the time from peak to peak or from bottom to bottom, which is determined from the time fluctuation of metabolic activity showing circadian rhythm. The free run cycle is approximately 24 hours for most plants, but more precisely, the inherent free run cycle of a plant can be shorter than 24 hours or longer than 24 hours. . In addition, the free-run cycle changes temporarily by providing a turn-off time of about several minutes to several hours called a so-called dark pulse (DP) under continuous illumination. In the present invention, the plant-specific free-run cycle determined under continuous illumination conditions or continuous dark conditions is used as a reference.

In this specification, “light period” means a time zone in which the light source is turned on and the cultivation light is irradiated. In this specification, “dark period” is used not only in the case where the light source is turned off and the cultivation light is not irradiated, but also in the meaning including the time period in which the light amount is lower than the light amount in the light period. That is, in the present invention, the control of cultivation light is mainly used in the sense of on / off control of the light source, but is also used in the sense of including increase / decrease control of the light amount. In this specification, the light period and dark period may be a time period of about 1 to 3 hours. Therefore, the “light / dark cycle” in the present specification refers to a pulsed dark period (DP: also referred to as a dark pulse) and a pulsed light period (LP: light) when the light period and the dark period are substantially equal or under so-called continuous illumination. (Also referred to as a pulse) is provided periodically. Further, when the light source is turned on in the dark period, the wavelength in the dark period and the wavelength in the light period may be different.

In the cultivation light control method of the present invention, the dark period is set to a time zone with low photosynthetic activity or the light period is set to a time zone with high photosynthesis activity. Here, the low photosynthetic activity means that the average value of the photosynthetic activity is about −10%, preferably −15%, and more desirably −20% or less. High photosynthetic activity means that the average value of photosynthetic activity is about + 10%, preferably + 15%, and more desirably + 20% or more. The time zone with low photosynthetic activity is determined from the circadian rhythm inherent in plants, but this time zone generally corresponds to 1 to 3 hours before dawn in the plant clock, that is, from 3 am to 5 am. The time zone with high photosynthetic activity is also determined from the circadian rhythm inherent in the plant, but this time zone roughly corresponds to 5 to 7 hours after dawn in the plant biological clock, that is, from 11 am to 1 pm. The method of the present invention includes (1) a method in which the end of the dark period is set to a time zone where the photosynthetic activity is low, that is, 1 to 3 hours before the dawn time in the biological clock of the plant, and (2) the dark period is photosynthetic activity The method includes setting a low time zone or light period of the photoperiod to a time zone with high photosynthetic activity.

(1) Method of setting the end of the dark period to a time zone with low photosynthetic activity This method uses the end of the dark period in the light-dark cycle as the previous 24-hour light-dark cycle (light period 12 hours, dark period 12 hours). The period of the dark period is advanced earlier, and the period of the dark period is decreased to a time zone with low photosynthetic activity, that is, about 1-3 hours before dawn time in the plant body clock, 0.92 ± 0.04 (rad / 2π) time zone. FIG. 1 is a conceptual diagram of the control method. It is known that the plant metabolism represented by photosynthetic activity fluctuates in a cycle of about 24 hours. As shown in FIG. 1 (a), in the light / dark cycle of 24 hours composed of the same period of light and dark periods. The end of the dark period coincides with the dawn time in the body clock. On the other hand, it is said that the photosynthetic activity is minimized at 1 to 3 hours before the dawn in the plant body clock, that is, the time from the dark period to the light period. The time 1 to 3 hours before dawn is a time zone in which the response to light is increasing, and the time of the biological clock is advanced by several hours by light irradiation. This is called phase advance or phase shift by light. In the method (1), as shown in FIG. 1 (b), by providing the end of the dark period 1-3 hours before dawn, the body time of the plant is advanced several hours by phase advance, and the photosynthetic activity is low. , Preferably the lowest time zone is deleted.

At this time, the time during which the end of the dark period can be advanced, that is, the difference between the cycle of the light-dark cycle and the free run cycle specific to the plant is within the range of time in which the circadian rhythm of the plant can be synchronized. If this difference is large, the light-dark cycle and the circadian rhythm cannot be synchronized, and as a result, the circadian rhythm will behave irregularly. If the circadian rhythm becomes irregular, it will not be possible to expect sufficient growth. The difference between the light-dark cycle period and the plant-specific free run period is at most 4 hours, 1 hour, 2 hours, and can be 3 hours. In addition, the optimum time is experimentally determined depending on the plant or the same plant. It can be said that the method (1) is a method in which the length of the light-dark cycle is made shorter than the plant-specific free-run cycle.

In this method, the proportion between the length of the light period and the length of the dark period in the light / dark cycle is appropriately determined. A light / dark cycle in which the length of the light period and the length of the dark period are the same or a light / dark cycle in which the length of the dark period is shorter than the length of the light period is preferable. This is because, by sufficiently shortening the dark period, it can be regarded as a continuous illumination condition, and the burden on the air conditioner and the like is reduced. In addition, since there is a possibility that the growth of the plant may decrease when the length of the light period is shortened, the length of the light period is the same as the length of the dark period or the length of the light period is 11 hours or more. A light / dark cycle is desirable.

The length of the light period and the length of the dark period are, for example, when the cycle of the light / dark cycle is 23 hours, the light period is about 11.5 hours, the dark period is about 11.5 hours, and the light period is about 12 hours. The dark period can be about 11 hours. Also, the light period can be about 13 hours and the dark period can be about 10 hours. When the cycle of the light-dark cycle is about 22 hours, the light period is about 11 hours, the dark period is about 11 hours, the light period is about 12 hours, the dark period is about 10 hours, the light period is about 13 hours, The dark period can be about 9 hours. When the cycle of the light-dark cycle is about 21 hours, the light period is about 10.5 hours, the dark period is about 10.5 hours, the light period is about 11 hours, the dark period is about 10 hours, and the light period is About 12 hours, the dark period can be about 9 hours.

Since this method uses the phase advance caused by the stimulus at the beginning of the light period, it is necessary to reduce the light amount in the dark period compared to the light period. The light quantity in the dark period is about ½ or less, about 1/5 or less, and about 1/10 or less, preferably zero, that is, turning off the light source.

This method maintains the advantage that the plant can be cultivated in a state close to the metabolic cycle inherent to the plant because the time when the plant subjectively feels dawn is advanced by several hours. In other words, since it is not a method of reversing the body time from night to day, the stress on the plant is small. If the stress on the plant is large, normal physiological metabolism cannot be maintained, and optimization of plant growth becomes difficult. In addition, according to this method, the plant growth apparatus is not significantly affected even though it is cultivated in a light / dark cycle having a cycle shorter than 24 hours within a range not destroying the circadian rhythm.・ Cost is reduced.

(2) Method of setting the dark period as a time zone with low photosynthetic activity or the light period as a time zone with high photosynthetic activity This method sets the dark period called dark pulse to a time zone with high photosynthetic activity under almost continuous irradiation. Or a method of setting a light period called a light pulse in a time zone in which photosynthetic activity is high. This method is a control method in which a short dark period or light period is set under continuous illumination, and is a control method using a pull-in phenomenon caused by a dark pulse or a light pulse. Under continuous illumination, when a dark pulse of about 2 hours is given at a certain period, the circadian rhythm of the plant is synchronized with the period and a phenomenon (phase lock) is observed that converges to a specific phase relationship. Has been reported (for example, Non-Patent Document 5). According to this method, the circadian rhythm of the plant is maintained, so that not only the promotion of cultivation by continuous lighting is expected, but also the power consumed by the light source is reduced as a result of a short turn-off, and the temperature changes rapidly. Therefore, the load on the air conditioner is also reduced.

The period for providing the dark period is determined by the following method. In this method, a phase response curve (G (φ)) is obtained from (A) a free-run period (τ) under continuous illumination conditions and a free-run period (τ ′) under continuous irradiation conditions with one dark period. And (B) an intersection of the dark phase and the phase response curve corresponding to a time zone with low photosynthetic activity within a time when phase synchronization of the circadian rhythm in the plant is possible (phase fixed point) ) To obtain a phase shift for providing a dark period. The phase response curve G (φ) depends on the time length of the dark pulse (also referred to as “dark pulse intensity”), and the length of the dark period coincides with the dark pulse intensity. The period (T) of the light / dark cycle is shown as the time (T = τ−ΔT) obtained by subtracting the phase shift (ΔT) from the free-run period (τ). The length of the dark period is the length of the dark pulse (Δt), and the length of the light period is the remaining time (T−Δt) of the cycle (T) of the light / dark cycle. Note that the sign of phase shift is represented by plus in the case of phase advance and minus in the case of phase backward.

The circadian rhythm measurement method is already known as described above. A method for obtaining a phase response curve is also known. The phase response curve is a phase shift based on the circadian rhythm under continuous illumination, that is, the phase difference between the circadian rhythm under continuous illumination and the circadian rhythm when a single dark pulse is applied under continuous illumination ( FIG. 5 is a diagram showing a relationship between a free run cycle (τ) −free run cycle (τ ′)) and a time (phase) at which a dark pulse is applied. FIG. 2 is a diagram showing the phase shift of circadian rhythm when a single dark pulse is given under continuous illumination, and this figure shows a state where a dark pulse is given 120 hours after the start of cultivation. ing. It can be seen that the application of dark pulses gives a phase lag to the circadian rhythm.

FIG. 3 shows an example of a phase response curve G (φ), which is a simulation of a plant having a free-run cycle of 23 hours. In the phase response curve, the vertical axis indicates the phase shift (rad / 2π) and the horizontal axis indicates the phase (rad / 2π) during dark pulse irradiation. The phase response curve is different depending on the intensity of the dark pulse. FIG. 3 is a phase response curve when a dark pulse of 2 hours (Δt = 2 hrs) is given. It is known that a regular circadian rhythm can be obtained when the phase is shifted by the application of a single dark pulse and the dark pulse is repeatedly applied in the same period (see, for example, Non-Patent Document 5). That is, the phase response curve means that a circadian rhythm having a period different from the free-run period between the maximum value and the minimum value of the phase shift (rad / 2π) indicated by the phase response curve can occur in the plant. ing. In other words, the phase lock occurs between the maximum and minimum values of the phase shift, resulting in a natural circadian rhythm that is different from the plant specific circadian rhythm, despite the cycle rhythm of the metabolic activity of the plant. Growth is expected.

Here, as described above, the photosynthetic activity decreases 1 to 3 hours before the subjective dawn time of the plant, that is, in a time zone where the phase is 0.94 ± 0.04 (rad / 2π). Therefore, when the dark period is set in this time zone, the light extinction time can be provided without greatly adversely affecting the growth of the plant. Therefore, the phase shift when the phase is 0.94 ± 0.04 (rad / 2π), that is, the phase shift corresponding to the phase on the phase response curve of 0.94 (rad / 2π) is obtained. When a dark pulse is applied at the time when this phase shift is obtained (phase fixing point), the phase of the circadian rhythm is fixed and a regular circadian rhythm is obtained.

More specifically, referring to FIG. 3, from the phase response curve shown in FIG. 3, the phase shift is in the range of −0.05 (rad / 2π) to 0.15 (rad / 2π), that is, 23 hours− From 1.15 hours (−0.05 × 23 hours) = 21.85 hours to 23 hours + 3.45 hours (0.15 × 23 hours) = 26.45 hours, the phase is locked and the plant It is understood that plants can grow with a circadian rhythm with a different period from the intrinsic circadian rhythm. Next, the phase shift at which the phase at which the dark pulse is applied becomes 0.94 (rad / 2π) is about −0.15 (rad / 2π), that is, the phase fixing point is 0.15 (rad / 2π) phase. Is at a late point. Therefore, the cycle (T) of the light / dark cycle is the time obtained by subtracting the phase shift (ΔT) from the free-run cycle (τ) under continuous illumination, that is, 23 hours × (1 − (− 0.15)) = 26.45. It becomes a light-dark cycle of time. Therefore, the light may be controlled by a light / dark cycle comprising a light period of 24.45 hours and a dark period of 2 hours (the length of the dark pulse).

3 shows the case where the length of the dark pulse is 2 hours. The peak of the phase response curve decreases as the dark pulse intensity decreases, and the height drawn by the phase response curve increases as the dark pulse intensity increases. When the dark pulse becomes stronger than a certain intensity, the phase response curve diverges and does not draw a continuous curve as shown in the figure, and a phase reset phenomenon occurs at a discontinuous point different from the synchronization phenomenon. Therefore, the intensity of the dark pulse is a time within a range where the synchronization phenomenon occurs, and the intensity, that is, the length of the dark period is approximately 4 hours or less. The intensity of the dark pulse is arbitrary as long as it is within this range, and is, for example, 4 hours, 3 hours, 2 hours, or 1 hour. This strength is determined experimentally.

In addition, when a dark pulse is applied, the phase tends to be slow, and the period for applying the dark pulse tends to be longer than the plant-specific free run period. In addition, as described above, if the intensity of the dark pulse is increased, the phase tends to be delayed, and if the intensity is increased too much, the synchronization phenomenon does not occur. Therefore, the period of applying the dark pulse is longer than 24 hours, and about 30 hours at the maximum. It is. Of course, depending on the varieties of plants or the same plant, the period for applying dark pulses may be 24 hours.

点灯 According to the lighting control method based on this light / dark cycle, cultivation similar to cultivation under continuous illumination is possible, and the period from cultivation start to harvesting is shortened compared to the method (1). Moreover, since the dark period is provided, power consumption is reduced by the amount corresponding to the dark period as compared to the cultivation method under continuous illumination.

The same applies when a light pulse is applied. The time for applying the light pulse is obtained from a phase response curve obtained when the light pulse is applied under continuous illumination. FIG. 4 is an example of a phase response curve when a write pulse of 2 hours (Δt = 2 hrs) is given. When a light pulse is applied, a light period is provided in a time zone in which photosynthetic activity is high. Depending on the time length of the write pulse (also referred to as “light pulse intensity”), the length of the light period coincides with the intensity of the write pulse. The time period in which the light period is provided is obtained by the same procedure as that for applying the dark pulse. The photosynthetic activity becomes high 5 to 7 hours after the subjective dawn time of plants, that is, in the time zone where the phase is 0.25 ± 0.04 (rad / 2π). Therefore, when a light period with a large amount of light is provided in this time zone, light with a high light amount is irradiated in a time zone with high photosynthetic activity, and the light amount in other time zones where the photosynthetic activity decreases can be set low. As a result, not only the utilization efficiency of cultivation light is improved, but also a high production rate by continuous illumination is expected. Therefore, a phase shift when the phase is 0.25 ± 0.04 (rad / 2π), for example, a phase shift corresponding to 0.25 on the phase response curve is obtained. In the example shown in FIG. 4, the phase shift at which the phase at which the write pulse is applied becomes 0.25, the phase shift is about 0.17 (rad / 2π), that is, the phase fixed point is 0.17 (rad / 2π) earlier. There is. Therefore, the period (T) of the light / dark cycle is 24 when the phase obtained by subtracting the phase shift (ΔT) from the free run period (τ) under continuous illumination, that is, when the inherent free run period of the plant is 24 hours. Time × (1−0.17) = 19.09 hours light-dark cycle. Therefore, it is sufficient to control the light in a dark cycle of about 17.1 hours and a light cycle of 2 hours (light pulse length).

The phase response curve in FIG. 4 shows the case where the length of the light pulse is 2 hours. When the intensity of the light pulse becomes weak, the curves drawn by the phase response curve approach each other, and when the intensity of the light pulse becomes strong, the curve drawn by the phase response curve leaves. When the light pulse becomes stronger than a certain intensity, the phase response curve shows only a single response, and a continuous response curve as shown in the figure is not drawn. That is, the phase reset phenomenon occurs, the phase synchronization phenomenon does not occur, and the phase control necessary in this illumination method cannot be performed. Therefore, the intensity of the write pulse is a time within a range where phase synchronization occurs, and the intensity, that is, the length of the light period is approximately 4 hours or less. If the time is within this range, the length of the write pulse is arbitrary, for example, 4 hours, 3 hours, 2 hours, or 1 hour. This strength is determined experimentally.

In addition, when a light pulse is applied, the phase tends to be earlier, and the period for applying the light pulse tends to be shorter than the plant-specific free run period. Further, as described above, if the intensity of the laut pulse is increased, the phase tends to be advanced, and if the intensity is increased too much, the synchronization phenomenon does not occur. Therefore, the period for applying the write pulse is shorter than 24 hours and is about 18 hours at the minimum. is there. However, depending on the plant or the same plant, the light pulse application cycle may be 24 hours.

Plants are cultivated under the cultivation light of the light and dark cycle set as described above. Light is needed after germination. Therefore, cultivation can be started simultaneously with germination under the light of the light and dark cycle. In addition, the plant is grown for a few days to 1-2 weeks in the light of light or natural light of a 24-hour day / night cycle (12 hours of light period and 12 hours of dark period), and then cultivated under the light of the above light and dark cycle. You may start. When cultivation is started with the light / dark cycle set above, the circadian rhythm of the plant gradually synchronizes and the plant's circadian rhythm gradually synchronizes with the light / dark cycle set, for example, the light / dark cycle of 22 hours. A metabolic cycle is formed. The harvesting time is appropriately determined according to the growth of the plant. It can also be cultivated in a 24-hour day / night cycle when the harvest time is approaching.

The plant cultivation method of the present invention includes a first cultivation period that is cultivated with the cultivation light of the light and dark cycle set by the above method and the light and dark cycle in the first cultivation period before and after the first cultivation period or both. It is the cultivation method which provided the light-dark cycle adjustment period grown under the cultivation light of the light-dark cycle which has a period between a period and 24 hours. The light / dark cycle adjustment period is an adjustment period for shifting from the light / dark cycle in the first cultivation period to the light / dark cycle having a 24-hour period.

The period of the light-dark cycle in the first cultivation period is a time shorter than 24 hours, a time longer than 24 hours, and may be 24 hours in some cases. When cultivated in a light / dark cycle with a 24-hour period, the biological clock of the plant has a 24-hour period, so the human rhythm (24-hour social cycle) at the start of cultivation coincides with the circadian rhythm of the crop. For example, when the light period starts at 10:00 am, 10:00 am becomes the end time of the dark period, and there is no error between the human life rhythm and the plant circadian rhythm at the start of cultivation and at the time of harvest. However, if the cycle of the light and dark cycle in the first cultivation period is not 24 hours, such as 22 hours, a deviation occurs between the human life rhythm and the plant circadian rhythm at the time of harvest. For this reason, when harvesting at an optimal harvest time in consideration of the circadian rhythm of the plant, for example, at 6 am in the body clock of the plant (the time when the light period switches to the dark period), the harvest time in the human life rhythm is May fall at midnight. In this case, an excessive burden is imposed on humans during harvesting. On the other hand, when it is attempted to start harvesting at 10:00 am with a 24-hour rhythm giving priority to human life rhythms, for example, the plant biological clock corresponds to, for example, around 12:00 am where photosynthesis activity is remarkably high, which is the best for harvesting. It is not always time. Moreover, if it changes suddenly from a 22-hour period to a 24-hour period, there exists a possibility that an excessive stress may be added to a plant. The light / dark cycle adjustment period is a cultivation period provided to eliminate such problems, and the biological clock of the plant is adjusted to a 24-hour cycle within this period.

FIG. 5 is a conceptual diagram showing a cultivation method provided with a light-dark cycle adjustment period. This figure shows a case where cultivation is started at 10 am and harvesting is started at 10 am. In this case, the light source is turned on at 10 am, and the metabolic rhythm of the plant is given priority immediately after the start of cultivation. For example, light is irradiated in a light / dark cycle of a period of 22 hours (light period 11 hours, dark period 11 hours). The cultivation is performed in the light-dark cycle for a while from the start of cultivation to the harvest time. When the harvest time approaches, the light-dark cycle having a period of 22.5 hours, the light-dark cycle having a period of 23 hours, 23. Cultivation is performed in a light / dark cycle having a period of 5 hours and a light / dark cycle in which the period gradually increases. In this way, it is possible to give priority to the metabolic rhythm of plants during the period of large plant growth, and gradually give priority to the human rhythm as the harvest approaches. As a result, not only efficient cultivation is possible, but also plant cultivation in consideration of human life rhythms can be achieved while reducing stress applied to the plant.

The period of the light / dark cycle in the light / dark cycle adjustment period is between the period of the light / dark cycle in the first cultivation period and 24 hours, which is the period of one light / dark cycle, and may be the period of two or more light / dark cycles. . The adjustment period (cultivation period) is also appropriately determined, and may be one day, two days, three days, or more. The length of the dark period and the length of the light period in the light / dark cycle are also arbitrary. From the viewpoint of stress reduction and synchronous control, the light / dark cycle in the light / dark cycle adjustment period is preferably a light / dark cycle approximate to the light / dark cycle in the first cultivation period. For example, if the light / dark cycle in the first cultivation period is a light / dark cycle with a period of 22 hours (light period 11 hours, dark period 11 hours), the light period is 11 hours and the dark period is 11.5 hours. The light-dark cycle adjustment period is exemplified as a light-dark cycle having a cycle of 11.5 hours and a light cycle of 11.5 hours, a light cycle of 11.5 hours and a light cycle of 12 hours. Moreover, if the light-dark cycle in the first cultivation period is a light-dark cycle having a dark period of 2 hours and a light period of 22.15 hours, cultivation of continuous irradiation without the dark period after the end of the first cultivation period It is good also as a period. The light / dark cycle adjustment period is arbitrary, and may be harvested immediately without providing the light / dark cycle adjustment period after the end of the first cultivation period.

The plant cultivation apparatus of the present invention includes a housing that accommodates a plant, a light source that emits light (cultivation light) for cultivating the plant, and a light source control unit that controls lighting of the light source. If the housing | casing which accommodates a plant can maintain the cultivation environment controlled artificially, the structure will not be ask | required. Moreover, the plant cultivation apparatus includes an air conditioning facility that manages humidity and temperature in a space that accommodates plants, and a culture facility that supplies a plant cultivation medium.

The light source is composed of LEDs, fluorescent lamps, etc., and irradiates light of a wavelength necessary for plant growth. The light source may be a light source that emits light of a fixed wavelength or a light source that emits light of a plurality of wavelengths. A light source capable of controlling the wavelength of light to be irradiated is preferably used. It is also known that plant growth is affected by the wavelength of light to be irradiated, and the wavelength of light is appropriately selected. For example, in a light period, a light source composed of a red LED may be turned on to emit red light, and in a dark period, a light source composed of a blue LED may be turned on to emit blue light. In the light period, the light source consisting of red LED and blue LED is turned on, and the mixed light of red light and blue light is irradiated. In the dark period, only the light source consisting of blue LED or the light source consisting of red LED is turned on. Thus, there may be a method of irradiating either one of red light and blue light. In particular, when using light pulses, turn on the light source consisting of the red LED throughout the dark period and turn on the light source consisting of the blue LED during the light period and irradiate both red light and blue light. Is desired. Blue light has the effect of darkening the green color of the leaves and hardening the leaves. For this reason, simultaneous irradiation of red light and blue light not only prevents the disappearance of the circadian rhythm due to continuous irradiation of red light, but also contributes to the formation of leaves.

The plant to be cultivated is not limited as long as it can grow in the housing. The plant can be an edible plant or an ornamental plant. The plant is preferably an edible plant and is an edible plant with a short growth period. Vegetables such as lettuce, Japanese mustard spinach, spinach, cucumber, tomato, pepper, sanchu, mizuna, spring chrysanthemum; fruits such as arugula and basil, fruits such as strawberry, mandarin, mango, grape, and pear Cereals such as rice, wheat, barley, rye, oat, corn, sorghum, millet, millet and millet are exemplified. Examples of ornamental plants include flower plants such as roses, carnations, orchids, gerberas, turkeys, and foliage plants such as pothos, serom, and Asiantum.

The light source control means includes, for example, a storage device such as a RAM and a hard disk device, a timer, a switch device that turns on and off the light source and switches the light source, an input device such as a keyboard and a touch sensor, and a computer device that controls these devices. Appropriate combinations are configured. The light / dark cycle (the length of the light period and the length of the dark period), the length of the first cultivation period, the light / dark cycle adjustment period, and the light / dark cycle (the length of the light period and the dark period) according to the cultivation light control method. Information required for cultivation (cultivation information) such as management temperature and management humidity during cultivation is input from the input device and stored in the storage device. The light source control means turns the light source on / off or adjusts the amount of light according to the inputted light / dark cycle, and switches the light source as necessary. When the light / dark cycle adjustment period is set, the light source control means controls the lighting of the light source in the light / dark cycle according to the cultivation light control method until the first cultivation period ends, and in the light / dark cycle adjustment period. The light source is controlled to be turned on until it can be harvested by a predetermined light / dark cycle.

The plant cultivation apparatus of the present invention may be further provided with a clock means for displaying the body time of the plant. The clock means includes a display means including a conversion means for converting the set light-dark cycle period (T) into a 24-hour display, a display for displaying the time converted by the conversion means, and the like. The conversion means is constituted by, for example, a computer device, and converts the set light / dark cycle period into a 24-hour display. For example, when the cycle of the light / dark cycle is set to 22 hours (light period 11 hours, dark period 11 hours), the plant advances the biological clock subjectively with 22 hours as one day. The conversion means converts the time in the biological clock of the plant into the time indicated in 24 hours, with 22 hours being 24 hours in order to match the biological clock with the human life rhythm (24-hour social system). That is, the conversion means calculates that the time when the light source is turned on is 6 am, which is the subjective dawn time of the plant, and the time after 11 hours when the light source is turned off is 6 pm. The time in the body clock is displayed on a display means including a display. Further, in the case of a light / dark cycle consisting of a dark pulse of 2 hours and a light period of the remaining time, the conversion means uses the central time at which the dark pulse (Δt = 2hrs) is given, for example, 4 am The dark period start time is 3 am and the dark period end time is 5 pm, and the time is displayed on the display means. The same applies when a write pulse is applied. By looking at the time displayed on the display means, the worker senses the life rhythm of the plant with a rhythm similar to that of the human life, and performs various operations such as fertilization and harvesting operations according to the biological clock of the plant.

Next, an example of a molecular diagnostic plant cultivation apparatus capable of obtaining a circadian rhythm, that is, a free-run cycle will be shown. An outline of the molecular diagnostic plant cultivation apparatus 101 is shown in FIG. A molecular diagnostic plant cultivation apparatus 101 shown in FIG. 13 is a plant cultivation apparatus provided with a molecular diagnostic system for diagnosing the growth state of a plant based on bioluminescence of luminescent molecules that increase with the growth of the plant. The molecular diagnostic system comprises a light projection means for projecting cultivated light for growing a luminescent gene-introduced plant into which a luminescent gene has been introduced, and an expression level of an endogenous gene increased with the growth of the luminescent gene-introduced plant. Luminescent image acquisition means for imaging as bioluminescence and acquiring a luminescent image; and growth state diagnosis means for diagnosing the growth state of the luminescent gene-introduced plant based on the amount of bioluminescence emitted from the luminescent image. In FIG. 13, various facilities (for example, a light source such as lighting, an air conditioner such as an air conditioner, and a hydroponic cultivation facility) provided in a general plant cultivation apparatus are omitted for easy understanding. Unless otherwise specified, it is assumed that these various facilities are installed. In this apparatus 101, three spaces of a seedling raising stage A, an early diagnosis stage B, and a cultivation stage C are formed in a space surrounded by the outer wall 150.

The seedling raising stage A is an area for raising seedlings during the seedling raising period (about several weeks after sowing), and a plurality of seedlings 110 aseptically seeded and germinated in a medium are stored in a seedling shelf 112. . The seedling rack 112 is equipped with a light source for irradiating the seedlings 110 with cultivation light, that is, a light irradiation means 114. The light irradiation means 114 is not particularly limited as long as it is suitable as seedling cultivation light. For example, fluorescent lamps and LEDs are suitable.

Here, in the seedling (plant) used in the plant cultivation apparatus 101, a luminescent gene encoding a protein that performs bioluminescence is introduced into a promoter portion of an arbitrary target substance gene in advance using a genetic engineering technique. (Hereinafter referred to as a luminescent gene-introduced plant), the luminescent molecules increase with the growth of the luminescent gene-introduced plant, and the increased luminescent molecules react with the substrate to perform bioluminescence.

“Bioluminescence” is the emission of visible light by living organisms, and means luminescence using the mechanism of luminescence by luciferase such as fireflies, click beetles, luminescent bacteria (Photobacterium terephthalum, Vibrio harveyi, etc.), Cypridina, Renilla, Yakouchu, etc. . From the viewpoint of cost or availability of materials, the luminescent gene is preferably a gene encoding firefly-derived luciferase, and the luminescent molecule is preferably luciferase.

The early diagnosis stage B is an area for diagnosing the growth status of seedlings when selecting excellent seedlings before planting the seedlings 110 grown in the seedling stage A to the cultivation stage C described later. In the early diagnosis stage B, a dark box 120, a light emission image acquisition unit 122, a growth state diagnosis unit 124, and a selection unit 128 are installed.

FIG. 14 is a diagram for explaining the configuration of the molecular diagnostic system in the early diagnosis stage B. FIG. 15 is a flowchart showing the molecular diagnosis process of the molecular diagnosis system in the early diagnosis stage B.

The dark box 120 is capable of accommodating the seedling 110 and forming a dark space so that light from the outside does not enter. The structure is not particularly limited as long as it has such a function, and the size and shape can be arbitrarily designed.

The luminescent image acquisition means 122 is for acquiring a luminescent image by imaging bioluminescence emitted from the seedling 110 in the dark box 120. The luminescent image acquisition unit 122 is not particularly limited as long as it is a unit that can capture weak bioluminescence, such as a high-sensitivity CCD camera or a photomultiplier tube.

Further, the luminescent image acquisition means 122 is installed above the young seedling 110 in FIGS. 13 and 14 so that the seedling can be photographed from above. In addition, the luminescent image acquisition means 122 may be installed on the side surface of the dark box 120 so that it can be photographed from the side surface of the seedling 110, and a plurality of luminescent image acquisition means 122 is installed so that it can be photographed from each direction of the seedling 110. You can also. The luminescent image of the seedling 110 acquired by the luminescent image acquisition unit 122 is transmitted to the growth state diagnosis unit 124, and the image is stored in the image storage unit 126 (S100).

The growth state diagnosing means 124 diagnoses the growth state of the seedling 110 (luminescent gene-introduced plant body) based on the amount of bioluminescence emitted from the luminescent image acquired from the luminescent image acquiring means 122.

The light emission image information acquired by the growth state diagnosis unit 124 includes coordinate information (x _n , y _n ) of the seedling pallet 116. The growth state diagnosis means 241 acquires this coordinate information (S110), extracts a growth region (shown as a cell) of the seedling 110 corresponding to the coordinate information based on this coordinate information, and emits light in the growth region. Is measured (S120).

Here, the diagnosis result data of the growing state can be created based on the actual measurement value obtained by measuring the light emission amount, but in which position the seedling 110 is placed in the seedling stage A, for example, above or below the seedling shelf 112 Depending on whether it is close to or far from the light irradiation means 114, environmental differences such as when the seedling 110 grows well or conversely difficult to grow can occur. Therefore, even when diagnosing the breeding state, just judging the amount of bioluminescence itself as an absolute value, whether the seedlings were excellent due to the quality of whether or not the seedling was excellent, It is unclear whether the environment of the place where it was placed was bad and the growth was unsatisfactory. As a result, it was unclear whether the absolute amount of bioluminescence was measured and there was a possibility of misjudgment in the essence of selecting excellent seedlings.

Therefore, it is preferable to determine whether the amount of luminescence is large or small after correcting the amount of bioluminescence with the correction coefficient obtained in advance at each position in the seedling stage A (S130). This correction coefficient is a coefficient for considering the environmental difference from the past growth state, and correction by the correction coefficient is arbitrary.

That is, the growth state diagnosis means 124 calculates a correction coefficient for each position of the seedling 110 based on the position information of the seedling 110 (luminescent gene-introduced plant body) and the average light emission amount, and corrects the measured value of the light emission amount by the correction coefficient. It is preferable to provide an algorithm.

Specifically, if a sufficiently large number of seedlings are raised, it can be expected that the amount of emitted light will eventually be almost the same at any position. Therefore, the actual value of the average light emission amount for each position as a result of raising the seedlings a sufficiently large number of times is obtained, and the average value is obtained for the seedlings at positions that are less than the average value of the light emission amount obtained by adding all the positions. The coefficient which can correct | amend to raise to is obtained beforehand. Conversely, for the seedlings at a position higher than the average value, a coefficient that lowers the average value is obtained. By applying these correction factors to the measured value of the amount of luminescence measured in subsequent raising seedlings, it is possible to estimate and judge the original qualities of whether the seedlings themselves are excellent regardless of the position of the seedlings. It becomes possible.

FIG. 16 shows an example of data in which the correction algorithm is set in the coordinate information (x _n , y _n ) of the nursery pallet 116. As shown in FIG. 16, the correction algorithm is performed in correspondence with the coordinate information of the nursery pallet 116.

After correcting the actual measurement value, the reference value is compared with the actual measurement value (S140), and diagnostic result information on the growing state is created (S150).

FIG. 17 is an example of a luminescent image of the seedling 110 taken by the luminescent image acquisition means 122 and diagnostic result data of its growth state. As shown in FIG. 17A, when a 4 × 4 cell seedling pallet 116 is photographed from above the seedling 110 in the dark box 120, various luminescence image data of bioluminescence emitted from the two leaves of the seedling 110 can be acquired. . This bioluminescence is generated when a luminescent gene is expressed in a plant to produce a luminescent molecule, and luciferin contained in the substrate reacts with the luminescent molecule.

Also, the amount of bioluminescence emitted correlates with the quality of the growth state of the seedling 110, and it means that the seedling with a larger amount of light emission (110a in FIG. 17A) is more excellent. On the other hand, when the seedling 110 has a defect in nature, poor growth, or the luminescent gene is not expressed for some reason, the amount of luminescence is small or bioluminescence does not occur at all and the photographed image Is not projected (110b, 110c, 110d in FIG. 17A).

A reference value (threshold value) for the amount of luminescence serving as a reference for selection of the young seedlings 110 is set in advance in the growth state diagnosis unit 124, and a seedling (for example, 110a) exhibiting an amount of luminescence exceeding the reference value is set to the next cultivation stage The seedlings (for example, 110b, 110c, and 110d) for which the diagnosis information “◯” that permits the planting to C is created and shows only the light emission amount less than the reference value do not permit the planting to the next cultivation stage C “ “×” diagnostic information is created, and the diagnostic information is transmitted to the sorting means 128.

In addition, although the example of the seedling pallet 116 of 4x4 cells was demonstrated in FIG. 17 (A), the seedling pallet can set an arbitrary number of cells, and the diagnosis of the growing state should be performed for every arbitrary number of cells. Can do.

The sorting unit 128 acquires the diagnostic information created by the growth state diagnosing unit 124, and sorts out excellent seedlings and defective seedlings based on the diagnostic information. Although the configuration of the sorting means 128 is not shown, for example, a robot hand unit capable of holding a seedling together with the culture medium so as not to damage the plant, and the held seedling can be transferred from the raising seedling stage A to the cultivation stage C or a disposal box. It can be set as the structure by a simple conveyance part.

Excellent seedlings (for example, 110a) are transplanted to a cultivation palette (fixed planting palette 144) used in the cultivation stage C, and defective seedlings (for example, 110b, 110c, 110d) are discarded.

In this way, in the early diagnosis stage B, excellent seedlings can be selected with high accuracy at the stage of the seedling raising stage, and therefore, cost reduction and productivity increase are achieved by improving the yield rate and average production amount in the cultivation stage C. Is done.

FIG. 18 shows a correlation diagram between the dry weight after cultivation and the leaf area of the seedling, and the dry weight after cultivation and the luminescence amount of the seedling. In any case, it is recognized that there is a positive correlation, and it can be seen that the leaf area of the seedling and the amount of luminescence of the seedling can be used as an index for early diagnosis. They are also generally available under various light environments.

When comparing the correlation coefficient RDV between the leaf area of the seedling and the dry weight and the correlation coefficient RDB between the luminescence amount and the dry weight of the seedling, RDV <RDB in all test conditions. Therefore, the amount of luminescence is superior to the leaf area as an indicator for early diagnosis of dry weight.

Furthermore, FIG. 19 shows the correlation between the total amount of promoter activity (total photoprotein production amount: Net LUC production) and the leaf area of seedlings, and the total amount of promoter activity and the amount of luminescence of seedlings. In any case, it is recognized that there is a positive correlation, and it can be seen that the leaf area of the seedling and the amount of luminescence of the seedling can be used as an index for early diagnosis. They are also generally available under various light environments.

Further, when the correlation coefficient RLV between the leaf area of the seedling and the total promoter activity was compared with the correlation coefficient RLB between the amount of luminescence of the seedling and the total promoter activity, RLV <RLB was found in all test conditions. Therefore, the amount of luminescence is superior to the leaf area as an index for early diagnosis of the total promoter activity.

Cultivation stage C is an area where selected excellent seedlings (eg, 110a) are cultivated using a hydroponic cultivation system or the like. As shown in FIG. 13, the cultivation stage C includes a cultivation apparatus 136 composed of a light irradiation means 130 for promoting the growth of the plant body, a hydroponic cultivation means 132, a temperature and humidity management means 134, and the like. In addition, a luminescent image acquisition unit 138 and a growth state diagnosis unit 140 are installed.

FIG. 20 is a diagram for explaining the configuration of the molecular diagnostic system in the cultivation stage C. FIG. 21 is a flowchart showing the molecular diagnosis process of the molecular diagnosis system in the cultivation stage C.

The cultivation apparatus 136 controls the light irradiation of the light irradiation means 130, irradiates the cultivation light suitable for the growth of the luminescent plant 100 into which the luminescent gene has been introduced, and temporarily performs the molecular diagnosis in a dark box state ( Non-irradiation state) or bright box state (continuous irradiation state) can be created.

The luminescent image acquisition means 138 is for acquiring a luminescent image by imaging bioluminescence emitted from the luminescent plant 100 in the cultivation apparatus 136. The luminescent image acquisition unit 138 is not particularly limited as long as it is a unit that can capture weak bioluminescence, such as a high-sensitivity CCD camera or a photomultiplier tube.

Further, the luminescent image acquisition means 138 is installed above the plant body in FIGS. 13 and 20 so that the luminescent plant 100 can be photographed from above. In addition, the luminescent image acquisition means 138 may be installed on the side of the dark box 120 so that it can be photographed from the side of the seedling 110, and a plurality of luminescent image acquisition means 138 is installed so that it can be photographed from each direction of the seedling 110. You can also.

The luminescent image of the luminescent plant 100 acquired by the luminescent image acquiring unit 138 is transmitted to the growth state diagnosing unit 140 and stored in the image storage unit 142 (S200).

The growth state diagnosing unit 140 diagnoses the growth state of the luminescent plant 100 (luminescent gene-introduced plant body) based on the amount of bioluminescence emitted from the luminescent image acquired from the luminescent image acquiring unit 138, and environmental conditions such as cultivation light. It creates information to control.

The light emission image information acquired by the growth state diagnosis unit 140 includes coordinate information (x _n , y _n ) of the planting pallet 144, and the growth state diagnosis unit 140 acquires this coordinate information (S210), Based on the coordinate information, the area of each luminescent plant 100 is extracted and the amount of luminescence is measured (S230). Here, the diagnosis result data of the growing state can be created based on the actual measurement value obtained by measuring the light emission amount, but the correction algorithm implemented in the seedling raising stage A can also be executed.

Next, based on the obtained measurement value of luminescence, the growth state diagnosis means 140 creates molecular diagnostic information based on the obtained measurement value of luminescence (S240). Examples of molecular diagnostic information include useful gene expression information, photosynthetic gene expression information, circadian rhythm (circadian rhythm) information, and other gene expression information effective in the cultivation process. For example, when the molecular diagnostic information is circadian rhythm information, first, the phase response curve of the circadian rhythm of the luminescent plant 100 with respect to extinction (dark pulse DP) of about 2 hours under continuous illumination conditions, and under continuous illumination conditions Measure the free duration period. Next, based on the phase oscillator model using this phase response curve, the synchronization region and the phase fixed point of the dark period pulse are calculated.

Based on the synchronization region information and phase fixing point information that has been created, the growth state diagnosis means 140 realizes a phase fixing point in the time zone where the photosynthetic activity is lowest (in the state in which the body time is midnight, about 15% reduction of the average value). The period of the dark period pulse DP to be performed is determined (S250).

FIG. 22 is an example of circadian rhythm information created based on the measured light emission amount. As shown in FIG. 22, the amount of light emission increases and decreases with a period of about one day. Although the period differs depending on the kind of plant and the cultivation condition, as shown in FIG. 22, the circadian rhythm period and amplitude, and the response to the dark period pulse (DP) can be diagnosed.

FIG. 23 is an example of expression information of a photosynthesis-related gene (chlorophyll AB-binding protein gene CAB) created based on the measurement value of the luminescence amount of luciferase gene-introduced green wavelet LsCAB :: LUC. As shown in FIG. 23, the photosynthetic genes are increased or decreased with a period of about one day. In the case of a green wave lettuce, photosynthesis can be efficiently performed by applying a dark period pulse (DP) at the timing of the arrow shown in FIG.

The growth state diagnosing means 140 that has acquired the determined period information of the dark period pulse DP controls the irradiation time of the cultivation light of the light irradiation means 130, for example, turns off for about 2 hours for each period of the dark period pulse DP ( S260).

Thus, in the cultivation stage C, by calculating the “optimum period of dark period pulse” and practicing it, it is possible to save lighting costs and to efficiently synthesize the luminescent plant 100.

In addition, in said embodiment, although the example which cultivates the selected excellent seedling (110a) in the cultivation stage C was shown, it is not limited to this, For example, the young seedling which has not introduce | transduced the luminescent gene is grown in the cultivation stage C In this case, it can be cultivated together with a luminescent gene-introduced plant body (young seedling) selected in the above manner.

That is, in the cultivation stage C, the luminescent gene may not be introduced into all plants, and if the luminescent gene is introduced into a part (for example, one individual), the molecular diagnosis described above for the individual is performed. And information for the dark period pulse and other environmental control can be obtained. At that time, the luminescent gene-introduced plant plays a role as a kind of biological sensor. As a result, the result of sensing a part of the luminescent gene-introduced plant can be applied to the plant of the entire cultivation stage C. Therefore, even when cultivating a non-recombinant, optimal cultivation using molecular diagnostic information Can be performed.

It should be noted that the luminescent gene-introduced plant body can be discarded after its role is finished and handled so as not to be mixed with the non-recombinant to be shipped.

Suitable plants that can be used in the molecular diagnostic plant include vegetables such as lettuce, Japanese mustard spinach, spinach, cucumber, tomato, green pepper, sanchu, mizuna, and spring chrysanthemum; herbs such as arugula and basil; strawberries, mandarin and mango Fruits such as grapes, pears; grains such as rice, wheat, barley, rye, oats, corn, sorghum, millet, millet, millet; Various agricultural products such as foliage plants such as cerome and Asian tam can be mentioned.

In the molecular diagnostic plant cultivation apparatus 101, the growth state diagnosis means 140 in the cultivation stage C measures a free continuous period from the measured light emission amount under continuous illumination conditions, and obtains a circadian rhythm peculiar to the luminescent plant 100. You can also. And from the circadian rhythm peculiar to the obtained luminescent plant 100, the growth state diagnosis means 140 determines the light / dark cycle of illumination based on said luminescence control method, and controls the irradiation time of the cultivation light by the light irradiation means 130 it can. According to this method, since the circadian rhythm by the excellent seedlings selected at the early diagnosis stage is measured, more appropriate molecular diagnosis information can be obtained for the determination of the light / dark cycle. Thereby, a plant can be raised more efficiently in an artificial environment. However, since the growth state diagnosis means 124 in the cultivation stage B can also obtain the circadian rhythm peculiar to the luminescent plant 100, after measuring the circadian rhythm, the light / dark cycle is determined by the light emission control method, and the light irradiation means 130. It is also possible to control the irradiation time of the cultivation light.

The cultivation light control method of the present invention is a method for controlling cultivation light based on an algorithm based on a circadian rhythm peculiar to plants. According to the cultivation light control method of the present invention, the dark period or the light period is set to a period that takes into account the activity of photosynthesis, so that not only can the power saving effect be achieved by turning off the cultivation light, but the circadian rhythm of the plant is destroyed. Plants can be cultivated without any problems. As a result, it is possible to perform cultivation with high cost performance in consideration of lighting costs, air conditioning maintenance costs, plant growth, and the like.

Further, if the molecular diagnostic method of the present invention is used, a plant cultivation apparatus capable of controlling the environment most suitable for the plant body at the molecular level is provided.

DESCRIPTION OF SYMBOLS 11 Case 12 Light source 13 Cultivation space 20 Computer 40 which comprises a light source control means Display 100 ... Luminous plant 101 ... Molecular diagnostic type plant cultivation apparatus
DESCRIPTION OF SYMBOLS 110 ... Seedling 112 ... Raising shelf 114 ... Light irradiation means 116 ... Raising seedling pallet 120 ... Dark box 122 ... Luminous image acquisition means 124 ... Growth state diagnostic means 126 ... Image storage means 128 ... Sorting means 130 ... Light irradiation means 132 ... Hydroponics Means 134 ... Temperature and humidity management means 136 ... Cultivation device 138 ... Luminous image acquisition means 140 ... Growth state diagnosis means 142 ... Image storage means 144 ... Planting palette 150 ... Outer wall A ... Seedling stage B ... Early diagnosis stage C ... Cultivation stage

Claims (17)

1. A cultivation light control method for cultivating a plant by irradiating cultivation light under an artificially controlled light-dark cycle,
   The light-dark cycle has a light period in which cultivation light is irradiated, and a dark period in which a light amount less than the light amount in the light period is irradiated or there is no light amount,
   The cycle of the light-dark cycle is a cycle different from the inherent free run cycle of the plant,
   A cultivation light control method in which the dark period is set to a time zone with low photosynthetic activity or the light period is set to a time zone with high photosynthetic activity.
2. The cultivation light control method according to claim 1, wherein the free run cycle is obtained by the following method.
   A method for determining the growth state of a plant body based on bioluminescence of the plant body modified so that the expression level of an endogenous gene that increases as the plant grows can be identified by bioluminescence,
   A light projection step of projecting cultivating light to grow a luminescent gene-introduced plant into which the luminescent gene has been introduced;
   A luminescence image acquisition step of capturing a luminescence image by imaging the expression level of an endogenous gene increased with the growth of the luminescence gene-introduced plant as bioluminescence; and
   A method comprising a step of obtaining a cycle of a light / dark cycle from the expression level based on a light emission amount of bioluminescence in the luminescence image.
3. The difference between the cycle of the light-dark cycle and the inherent free-run cycle of the plant is within a time range in which phase synchronization of the circadian rhythm of the plant is possible,
   The cultivation light control method according to claim 1 or 2, wherein the end of the dark period is set to a time zone in which photosynthetic activity is low.
4. The cultivation light control method according to claim 3, wherein the end of the dark period is set 1 to 3 hours before the dawn time in the biological clock of the plant.
5. The cultivation according to claim 3 or 4, wherein the light / dark cycle is a light / dark cycle in which the length of the light period is substantially equal to the length of the dark period, or the length of the dark period is shorter than the length of the light period. Light control method.
6. The cultivation light control method according to any one of claims 3 to 5, wherein a difference between the cycle of the light-dark cycle and the inherent free-run cycle of the plant is within 3 hours.
7. The cultivation light control method according to any one of claims 3 to 6, wherein the light / dark cycle has a light period of about 11 hours and a dark period of about 11 hours.
8. The length of the dark period is the time that allows phase synchronization of the circadian rhythm of the plant,
   The cultivation light control method according to claim 1, wherein the dark period is determined by the following steps (A) and (B).
   (A) A step of obtaining a phase response curve from a free run period under continuous illumination conditions and a free run period under continuous irradiation conditions with a single dark period (B) Phase synchronization of circadian rhythm in the plant A step of obtaining a phase shift for providing a dark period from an intersection of a phase corresponding to a time zone having low photosynthetic activity and a phase response curve within a possible time.
9. The cultivation light control method according to claim 8, wherein the free run cycle is obtained by the following method.
   A method for determining the growth state of a plant based on the bioluminescence of the plant modified so that the expression level of an endogenous gene that increases with the growth of the plant can be identified by bioluminescence,
   A light projection step of projecting cultivating light to grow a luminescent gene-introduced plant into which the luminescent gene has been introduced;
   A luminescence image acquisition step of capturing a luminescence image by imaging the expression level of an endogenous gene increased with the growth of the luminescence gene-introduced plant as bioluminescence; and
   A method comprising a step of obtaining a free-run cycle from the expression level based on a bioluminescence emission amount in the luminescence image.
10. The cultivation light control method according to claim 8 or 9, wherein the end of the dark period is set 1 to 3 hours before the dawn time in the plant biological clock.
11. The cultivation light control method according to any one of claims 8 to 10, wherein the length of the dark period is within 3 hours.
12. A molecular diagnostic method for diagnosing the growth state of a plant based on the bioluminescence of the plant modified so that the expression level of an endogenous gene that increases with the growth of the plant can be identified by bioluminescence,
    A light projection step of projecting cultivating light to grow a luminescent gene-introduced plant into which the luminescent gene has been introduced;
    A luminescence image acquisition step of capturing a luminescence image by imaging the expression level of an endogenous gene increased with the growth of the luminescence gene-introduced plant as bioluminescence; and
    A growth state diagnostic step of diagnosing the growth state of the luminescent gene-introduced plant based on the amount of bioluminescence emitted in the luminescent image;
    A molecular diagnostic method.
13. The molecular diagnostic method according to claim 12, wherein the luminescent gene is a gene encoding luciferase, and the luminescent molecule is luciferase.
14. A housing for accommodating plants;
    A light source that emits cultivation light for cultivating plants;
    A plant cultivation apparatus comprising light source control means for controlling lighting of the light source,
    9. A plant cultivation apparatus, wherein the light source control means controls cultivation light according to the cultivation light control method according to claim 1.
15. The plant cultivation apparatus according to claim 14, further comprising a clock unit that converts the period (T) of the light-dark cycle into a 24-hour display.
16. A plant equipped with a molecular diagnostic system for diagnosing the growth state of a plant body based on the bioluminescence of the plant body modified so that the expression level of an endogenous gene that increases as the plant grows can be identified by bioluminescence A cultivation device,
    The molecular diagnostic system comprises:
    A light projection means for projecting cultivation light for growing a luminescent gene-introduced plant into which a luminescent gene has been introduced;
    Luminescent image acquisition means for capturing the luminescence image by imaging the expression level of the endogenous gene increased with the growth of the luminescent gene-introduced plant as bioluminescence,
    A growth state diagnostic means for diagnosing the growth state of the luminescent gene-introduced plant based on the amount of bioluminescence emitted from the luminescent image;
    A plant cultivation apparatus comprising:
17. The plant cultivation apparatus according to claim 16, wherein the luminescent gene is a gene encoding luciferase, and the luminescent molecule is luciferase.

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