Device for measuring biogenic information and method for measuring biogenic information

Abstract

To provide a device for measuring biogenic information that can easily measure, without using a system with a complex configuration, various biogenic information of plants with leaves that have bilateral stomata, including the carbon dioxide assimilation rate of the leaves, the water vapor conductance in the stomata, and the carbon dioxide concentration in the leaves.SOLUTION: The device for measuring biogenic information (1) according to the present invention comprises: a first container (10) for covering at least a portion of one side of an amphistomatic leaf; a second container (20) for covering at least a portion of the other side of the leaf; and sensors (30a, 30b, 30c) for measuring a concentration of carbon dioxide, which are provided inside and outside of the first container (10) and inside the second container (20). At least a portion of a wall (11) constituting the first container (10) is made of a permeable material (12) having resistance to permeation of carbon dioxide.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a biological information measuring device and a method for measuring biological information. [Background technology]

[0002] In order to optimize the cultivation environment and automate cultivation management, it is necessary to accurately evaluate the biological information of plants. Conventionally, the evaluation of biological information of plants has been based on the external appearance of the plant, and also on the intuition and experience of the grower.

[0003] That is, the evaluation of the biological information of plants has been performed by human visual inspection, etc., but it has been difficult for producers other than experienced producers to accurately evaluate the biological information of plants. In addition, scientific data on the biological information of plants cannot be obtained non-destructively, accurately, and easily, making it difficult to optimize the cultivation environment and automate cultivation management. Furthermore, it is preferable to detect signs of biological information before changes appear in the appearance of the plant. For this reason, various proposals have been made for biological information measuring devices and biological information measuring methods that can easily evaluate the biological information of plants.

[0004] For example, Non-Patent Document 1 proposes a method for measuring biological information of plants using a ventilated chamber. In Non-Patent Document 1, the flow rate of air entering the chamber (μ r ) and the water vapor concentration in the air entering the chamber (W r ) and the water vapor concentration in the air leaving the chamber (W s ) and compare the measured value with the leaf area (S l ) and the transpiration rate (E) of the leaves of plants, which is known as the biological information of plants, is calculated by the following equation (1). In addition, in the above-mentioned Non-Patent Document 1, the carbon dioxide concentration (C r ) and the carbon dioxide concentration in the air leaving the chamber (C s ) and the above-mentioned measured value (μ r , Wr , W s ) and these measurements (C r , C s ) and leaf area (S l ) and the carbon dioxide assimilation rate (A) of the plant leaves, which is also known as biological information of the plant, is calculated using the following equation (2). Calculated: TIFF2025059205000003.tif6164.

[0005]

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[0006]

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[0007] In addition, in the above-mentioned Non-Patent Document 1, the saturated water vapor concentration (W i ) and the water vapor concentration in the air of the leaf being measured (W a ) and the water vapor concentration (W i , W a )of Based on the calculated transpiration rate (E), the water vapor conductance (g w ) Calculate TIFF2025059205000007.tif8165 and use the calculated value (g w ) and the boundary layer conductance of the plant leaf to water vapor (g bw ) and the water vapor conductance (g sw ) TIFF2025059205000008.tif8160. In a well-stirred chamber, W a W s As will be described later, the boundary layer conductance (g bw) is a value that varies depending on the vital sign measuring device used, and for example, a value measured by the method described in Non-Patent Document 2 is used.

[0008]

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[0009]

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[0010] Furthermore, in the above Non-Patent Document 1, the calculated value (g sw ) and the above measured value (g bw ) and the carbon dioxide conductance (g c ) TIFF2025059205000011.tif8165 is calculated. And the calculated value (g c ) and the carbon dioxide concentration in the leaf atmosphere (C a Based on the measured value of the transpiration rate (E) and the calculated carbon dioxide assimilation rate (A), the carbon dioxide concentration in the leaf (C), which is also known as biological information of plants, is calculated by the following equation (6). i ) is calculated. In a well-stirred chamber, C a is C s It can be regarded as:

[0011]

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[0012]

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[0013] In addition, in the above-mentioned Non-Patent Document 1, the calculated carbon dioxide assimilation rate (A) and the carbon dioxide concentration in the leaf (C i A method is presented to assess photosynthetic metabolic activity based on its relationship with [Prior art documents] [Non-patent literature]

[0014] [Non-Patent Document 1] von Caemmerer, S. and GDFarquhar (1981). “Some Relationships between the Biochemistry of Photosynthesis and the Gas-Exchange of Leaves.” Planta 153(4):376-387. [Non-Patent Document 2] Ball, JT (1987). “Calculations related to gas exchange.” Stomatal function 20:445-476. [Non-Patent Document 3] GDFarquhar. von Caemmerer, S. and JABerry (1980). “A Biochemical Model of Photosynthetic CO2 Assimilation in Leaves of C3 Species.” Planta 149:78-90. Summary of the Invention [Problem to be solved by the invention]

[0015] However, the biological information measuring device of the above-mentioned Non-Patent Document 1 was used to measure the carbon dioxide concentration (C i In order to calculate the transpiration rate (E) and the carbon dioxide assimilation rate (A) of the plant leaves, as shown in the above formula (6), it is necessary to simultaneously calculate the saturated water vapor concentration (W i ), it is necessary to measure the temperature of the leaves (see formula (3)). For this reason, in the method of measuring biological information in the above-mentioned Non-Patent Document 1, sensors for measuring the concentrations of water vapor and carbon dioxide to calculate at least the transpiration rate (E) and the carbon dioxide assimilation rate (A), and a flow rate of air entering the chamber (μ rIt was necessary to prepare a vital information measuring device equipped with a sensor to measure the vital information concentration (vital concentration) and a leaf temperature sensor to measure the leaf temperature.

[0016] Thus, in the past, the carbon dioxide assimilation rate (A) of the leaves of plants and the water vapor conductance (g sw ), and leaf carbon dioxide concentration (C i A biological information measuring device that includes the calculation of the above-mentioned parameter (a) tends to have a complex configuration and tends to be difficult to operate.

[0017] The present invention has been made in view of the above circumstances, and its object is to measure the carbon dioxide assimilation rate (A) and water vapor conductance (g) of the leaves of amphoteric plants. sw ), and leaf carbon dioxide concentration (C i The present invention provides a biological information measuring device and a biological information measuring method capable of easily measuring biological information of various plants, including plants such as cereals and vegetables, without using a system with a complex configuration. [Means for solving the problem]

[0018] In order to achieve the above object, the inventors have conducted extensive research and have found that a biological information measuring device is provided with a first container, a second container, and a sensor, and at least a part of the wall of the first container is made of a permeable material having permeability resistance to carbon dioxide, thereby enabling the measurement of the carbon dioxide assimilation rate (A) of the leaves of a plant having double-sided stomata and the water vapor conductance (g sw ), and leaf carbon dioxide concentration (C i The present invention was completed based on the discovery that it is possible to easily measure biological information of various plants, including plants containing phytoplankton, chlorophyll, and chlorophyll.

[0019] Specifically, the bioinformation measuring device of the present invention comprises a first container for covering at least a portion of one side of a bilaterally stomata plant leaf, a second container for covering at least a portion of the other side of the plant leaf, and sensors for measuring carbon dioxide concentration provided on the inside and outside of the first container and the inside of the second container, wherein at least a portion of the wall constituting the first container is made of a permeable material having resistance to carbon dioxide permeation.

[0020] According to this configuration, first, at least a part of one surface of the leaves of the plant is covered with the first container, and the concentration of carbon dioxide (C ex ) and the concentration of carbon dioxide outside the first container (C out ) and permeability resistance (g fc ) the carbon dioxide assimilation rate (A) in plant leaves, which is known as plant bioinformation, can be calculated using the following equation (7).

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[0021] Here, formula (7) is the formula when the leaf area measured by the sensor and the area of ​​the permeable material are the same, and when the leaf area and the area of ​​the permeable material are different, the carbon dioxide assimilation rate (A) can be calculated using the following formula (7'). Note that the leaf area here specifically means the area subject to gas exchange measurement, and the area of ​​the permeable material means the area in contact with the outside air through which gas can pass.

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[0022] In the above formulas (7) and (7'), the diffusion conductance (g fc ) can be, for example, a value calibrated by an existing measurement method.

[0023] Furthermore, at least a part of the other surface of the plant leaf is covered with a second container, and the concentration of carbon dioxide in the second container (C i(m) ) is expressed as the carbon dioxide concentration in the leaf (C i ) can be treated as

[0024]

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[0025] In addition, the calculated carbon dioxide assimilation rate in the leaves of plants (A) and the measured carbon dioxide concentration in the leaves (C i ) and the water vapor conductance (g sw ) can be calculated.

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[0026] According to this configuration, the carbon dioxide assimilation rate (A) in the leaves of a plant and the water vapor conductance (g) in the stomata are calculated based on the measurement results obtained only from the sensor that measures the concentration of carbon dioxide. sw ), and leaf carbon dioxide concentration (C i ) can be measured.

[0027] As described above, the biological information measuring device according to the present invention can measure the carbon dioxide assimilation rate (A) in the leaves of a plant having leaves with bifacial stomata, the water vapor conductance (g sw ), and leaf carbon dioxide concentration (C i This makes it possible to easily measure various plant biological information, including plant growth factors, without using a complex system.

[0028] The device may further include a calculator for calculating a carbon dioxide assimilation rate in the leaves of the plant based on the difference in carbon dioxide concentration between inside and outside the first container and the permeation resistance, and for calculating a water vapor conductance in the stomata of the leaves of the plant based on the carbon dioxide assimilation rate and the carbon dioxide concentration in the second container.

[0029] According to this configuration, the concentration difference of carbon dioxide between inside and outside the first container (C out -C ex ) and permeability resistance (g fc ), the carbon dioxide assimilation rate (A) in the leaves of the plant, which is known as bioinformation of the plant, can be calculated (see formula (7)). Furthermore, the calculated carbon dioxide assimilation rate (A) and the measured carbon dioxide concentration (C) in the second container can be calculated. i(m) ) and the water vapor conductance (g) in the stomata of plant leaves, which is known as a biological indicator of plants. sw ) can be calculated (see equations (9) and (10)).

[0030] The second container may cover a surface of the plant leaf opposite that covered by the first container.

[0031] According to this configuration, the second container covers the opposite side of the plant leaf covered by the first container, and thus the water vapor conductance (g sw ) can be measured with high accuracy.

[0032] Furthermore, the transmissive material may be configured to have a plurality of holes.

[0033] According to this configuration, since carbon dioxide can pass through while having a predetermined permeation resistance, the air inside the space formed by covering the leaves with the first container can be opened to the outside air, and the biological activity of the plant can be prevented from being hindered. In addition, the difference in carbon dioxide concentration (C out -Cex ), the rate of carbon dioxide assimilation in plant leaves (A) can be easily calculated (see equation (7)).

[0034] Specifically, the method for measuring biological information according to the present invention includes the steps of covering at least a portion of one side of a double-sided stomata plant leaf with a first container made of a permeable material, at least a portion of which has permeation resistance to carbon dioxide, to form a first space between the first container and the leaf, covering at least a portion of the other side of the plant leaf with a second container to form a second space, measuring the carbon dioxide concentration inside and outside the first space, measuring the carbon dioxide concentration inside the second space, calculating the carbon dioxide assimilation rate in the plant leaf based on the measured carbon dioxide concentration difference between the inside and outside of the first space and the permeation resistance, and calculating the water vapor conductance in the stomata of the plant leaf based on the carbon dioxide assimilation rate and the carbon dioxide concentration inside the second space.

[0035] According to this measurement method, first, a first space is formed by covering at least a part of one surface of a leaf of a plant with a first container. Since at least a part of the first container is made of a permeable material having a permeability resistance to carbon dioxide, the concentration of carbon dioxide (C ex ) and the concentration of carbon dioxide outside (C out ) and measure the concentration difference of carbon dioxide (C out -C ex ) and permeability resistance (g fc ) the carbon dioxide assimilation rate (A) in the leaves of a plant, which is biological information of the plant, can be calculated using the following equation (7).

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[0036] Here, formula (7) is the formula when the leaf area measured by the sensor and the area of ​​the permeable material are the same, and when the leaf area and the area of ​​the permeable material are different, the carbon dioxide assimilation rate (A) can be calculated using the following formula (7'). Note that the leaf area here specifically means the area subject to gas exchange measurement, and the area of ​​the permeable material means the area in contact with the outside air through which gas can pass.

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[0037] Furthermore, a second space is formed by covering at least a part of the other leaf of the plant with the second container, and the concentration of carbon dioxide inside the second space (C i(m) ) is expressed as the carbon dioxide concentration in the leaf (C i ) can be treated as

[0038]

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[0039] The calculated carbon dioxide assimilation rate in the leaves of the plants (A) and the measured carbon dioxide concentration in the leaves (C i) and the water vapor conductance (g sw ) can be calculated.

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[0040] According to this measurement method, the concentration of carbon dioxide (C ex ) and the concentration of carbon dioxide outside (C s ) and the concentration of carbon dioxide inside the second space (C i(m) ) to measure the rate of carbon dioxide assimilation in plant leaves (A), water vapor conductance in stomata (g sw ), and leaf carbon dioxide concentration (C i ) can be measured.

[0041] As described above, according to the method for measuring biological information of the present invention, for a plant having leaves with bifacial stomata as a measurement target, the carbon dioxide assimilation rate (A) of the leaves of the plant and the water vapor conductance (g) of the leaves of the plant can be measured without calculating the transpiration rate (E) of the leaves of the plant or measuring the temperature of the leaves. sw ), and leaf carbon dioxide concentration (C i ) can be easily calculated.

[0042] The second container may cover a surface of the plant leaf opposite that covered by the first container.

[0043] According to this measurement method, the second container covers the opposite side of the plant leaf covered by the first container, and thus the water vapor conductance (g sw ) can be measured with high accuracy.

[0044] Furthermore, the transparent material may have a plurality of holes.

[0045] According to this measurement method, since carbon dioxide can be transmitted while maintaining a certain resistance to transmission, the air inside the first space can be opened to the outside air, and the biological activity of the plant can be prevented from being hindered. In addition, the difference in carbon dioxide concentration (C out -C ex ) can be maintained, allowing the rate of carbon dioxide assimilation in plant leaves to be calculated (see equation (7)). Effect of the Invention

[0046] According to the biological information measuring device and biological information measuring method of the present invention, the carbon dioxide assimilation rate (A), the water vapor conductance (g sw ), and leaf carbon dioxide concentration (C i This makes it possible to easily measure various plant biological information, including plant growth factors, without using a complex system. [Brief description of the drawings]

[0047] [Figure 1] FIG. 1 is a side view for explaining a schematic diagram of a vital information measuring device according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a side view for explaining a typical example of use of the vital information measuring device according to one embodiment of the present invention. [Diagram 3] FIG. 3 is a schematic diagram for explaining a vital information measuring device according to the embodiment. [Figure 4] FIG. 4 is a graph showing the relationship (A-Ci curve) between the carbon dioxide assimilation rate (A) and the carbon dioxide concentration (Ci) in the leaf in the carbon dioxide response measurement. [Diagram 5] FIG. 5 is a graph showing the biochemical parameters of photosynthesis (Vcmax, Jmax) estimated from the A-Ci curves. [Figure 6] FIG. 6 is a graph showing the relationship between the carbon dioxide assimilation rate (A) measured at different leaf positions and the carbon dioxide concentration (Ci) in the leaf. [Figure 7] Figure 7 is a graph showing the change in evapotranspiration (g) of sunflower pot soil over time. [Figure 8] FIG. 8 is a graph showing the diurnal changes in stomatal water vapor conductance (gsw) in sunflower leaves during the day and night. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0048] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following preferred embodiments are merely exemplary in nature and are not intended to limit the present invention, its application method, or its uses.

[0049] (Bio-information measuring device) FIG. 1 is a side view for explaining a method for measuring biological information according to an embodiment of the present invention. As shown in FIG. 1, the biological information measuring device (1) according to this embodiment includes a first container (10) for covering at least a part of one side of a bifacial plant leaf, a second container (20) for covering at least a part of the other side of the plant leaf, and sensors (30a, 30b, 30c) for measuring the concentration of carbon dioxide, which are provided on the inside and outside of the first container (10) and the inside of the second container (20). Furthermore, as shown on the left side of FIG. 1, at least a part of the wall (11) constituting the first container (10) is made of a permeable membrane (12) that is a permeable material having permeation resistance to carbon dioxide.

[0050] In this specification, the term "plant bioinformation" refers to various parameters that are indicators of the biological activity of plants. For example, the plant bioinformation includes the transpiration rate (E) and carbon dioxide assimilation rate (A) (also simply called "photosynthetic rate (A)") in the leaves of a plant, water vapor concentration in the leaves (W i ) and leaf carbon dioxide concentration (C i ), and gas exchange parameters. Gas exchange parameters include the water vapor conductance (g sw ) and carbon dioxide conductance (g c ) etc.

[0051] In this embodiment, the biological information measuring device 1 is intended to measure biological information of a plant having bifacial stomatal leaves 40. The plant is not particularly limited as long as it has bifacial stomatal leaves 40, and examples of the plant include sunflower, strawberry, broad bean, soybean, basil, and tobacco.

[0052] In this embodiment, the first container (10) is a container for covering at least a part of one side of a leaf (40) of a plant having both sides pores, as shown on the left side of FIG. 1. The first container (10) has an opening and is composed of a wall (11) made of a material that does not allow gas to pass through. Specifically, in this embodiment, the wall (11) refers to a part that constitutes the bottom and side of the first container (10), and is not limited to a material having high hardness such as glass, but may also be an adhesive layer or the like described later. In addition, the first container (10) is not particularly limited as long as at least a part of the wall (11) that constitutes the container is composed of a permeable material that has permeation resistance to carbon dioxide. For example, the first container (10) may be a glass container that has an opening and is formed into a cylindrical shape, and at least a part of the wall that constitutes the container is composed of a permeable membrane (12) that is a permeable material. In addition, the material of the container is not limited to glass, and for example, a plastic container may be used. Furthermore, the number of permeable membranes (12) in the first container (10) is not particularly limited, and may be two or more. The first container (10) is not limited to an integrally molded container, and may be, for example, a container-shaped container as a whole, including a permeable membrane (12) constituting the bottom surface of the first container (10) and an adhesive layer (not shown) that is provided on the surface of the permeable membrane as the side of the first container (10) so as to surround a predetermined area of ​​the surface (for example, on the outer periphery of the surface of the permeable membrane) and adheres the plant leaf (40) and the permeable membrane (12). Such an adhesive layer may be a permeable material having permeation resistance. In that case, the permeable membrane (12) may be replaced with a membrane, plate, etc. made of an impermeable material (glass, plastic, etc.). Furthermore, a permeable material such as a sponge may be used instead of the adhesive layer, and in that case, adhesive layers may be provided on both ends of the permeable material to adhere to the leaf and the membrane, plate, etc. made of an impermeable material. In this way, the permeable material may be present on the side of the first container (10). In addition to these, for example, when a film-shaped sensor is used, such a film-shaped sensor may be configured as a part of the wall (11).

[0053] In this embodiment, the permeable material may be a membrane, plate, layer, or the like made of a material having resistance to carbon dioxide permeation, and the type of the permeable material is not particularly limited. The permeable material preferably has a moderate degree of carbon dioxide permeability and has a plurality of holes. For example, a nylon mesh made of plastic may be used as the permeable material.

[0054] FIG. 2 is a side view for explaining a typical example of use of the vital information measuring device (1) according to this embodiment. As described above, when the permeable membrane (12) is configured to have a plurality of holes (for convenience of illustration, these are indicated by dashed lines in the permeable membrane (12) in FIG. 2), carbon dioxide can pass through while having a predetermined permeation resistance, as shown in FIG. 2. This allows the air inside the first space (50) formed by covering the leaves (40) with the first container (10) to be released to the outside air, and prevents interference with the biological activity of the plant. In addition, the difference in carbon dioxide concentration (C s -C ex ), the carbon dioxide assimilation rate (A) in the plant leaf (40) can be calculated. Furthermore, the aperture ratio of the permeable membrane having a plurality of holes is preferably 1 to 50%, more preferably 5 to 50%, and even more preferably 10 to 50%. In this way, the space between the inside and outside of the first container (10) can be opened while maintaining a predetermined permeation resistance. As described above, in the measurement method of this embodiment, the carbon dioxide concentration (C a ) is the concentration of carbon dioxide (C ex ) and similarly, the water vapor concentration in the atmosphere of the leaf (40) being measured (W a ) is the water vapor concentration (W ex ) In addition, the concentration of carbon dioxide outside the first container in this embodiment (C out ) is the carbon dioxide concentration in the air leaving the chamber in the conventional method (C s )

[0055] In this embodiment, as shown in the right side of FIG. 1 and FIG. 2, the second container (20) is a container for covering at least a part of the other surface of the plant leaf (40) covered by the first container (10). The second container (20) is not particularly limited as long as it has an opening and is made of a wall of a material that does not allow gas to pass through. For example, a glass container having an opening and formed into a cylindrical shape can be used as the second container (20). The material of the container is not limited to glass, and for example, a plastic container can be used. The second container (20) is not limited to an integrally molded container, and may be, for example, a container-shaped container as a whole that includes an impermeable material such as an impermeable film or plate, and an impermeable adhesive layer (not shown) that is provided on the surface of the impermeable material so as to surround a predetermined area of ​​the surface (for example, on the outer periphery of the surface of the impermeable material) and adheres the plant leaf (40) to the impermeable material. Similarly to the first container (10), an impermeable film-like sensor may be configured as a part of the wall constituting the second container (20). 2, the second container (20) may cover the opposite side of the plant leaves (40) covered by the first container (10), but as long as the water vapor conductance can be calculated, the second container (20) may cover the opposite side of the plant leaves (40) covered by the first container (10) at an appropriate sliding position. Furthermore, the second container (20) is not limited to an integrally molded container, and may be, for example, a container including a membrane through which gas cannot pass and an adhesive layer (not shown) provided on the surface of the membrane so as to surround a predetermined area of ​​the surface and for adhering the membrane to the plant leaves (40).

[0056] In this embodiment, the sensors (30a, 30b, 30c) are not particularly limited as long as they can measure the concentration of carbon dioxide as shown in FIG. 1, and for example, commercially available sensors can be used. The sensors (30a, 30b, 30c) include a gas analyzer. Furthermore, the installation positions of the sensors (30a, 30b, 30c) are not limited as long as they can measure the carbon dioxide concentrations inside and outside the first container (10) and inside the second container (20). Furthermore, the sensor (30b) outside the first container (10) may be located away from the container, and may be capable of measuring the carbon dioxide concentration outside each container (in the atmosphere), and one outside sensor (30b) may be used for multiple first containers (10, 10, 10, . . . ). With this configuration, it is possible to easily measure biological information for multiple plant bodies.

[0057] Hereinafter, the calculation of the biological information of a plant by the biological information measuring device (1) according to this embodiment will be described with reference to FIG. 2. In the following example, the biological information of the plant is calculated based on the carbon dioxide assimilation rate (A) in the leaves of the plant, the carbon dioxide concentration in the leaves (C i ), and the water vapor conductance in the stomata of plant leaves (g sw ) will be explained in the following order:

[0058] For example, as shown in Fig. 2, consider a case in which a first container (10) of a vital information measuring device (1) covers at least a portion of one side of a double-sided stomata plant leaf (40), and a second container (20) covers the opposite side of the plant leaf (40). As a result, a first space (50) is formed by the first container (10) and the leaf (40), and a second space (60) is formed by the second container (20) and the leaf (40). Note that in Fig. 2, for convenience of illustration, stomata 41 in the plant leaf are indicated by dashed lines.

[0059] Then, the carbon dioxide assimilation rate (A) in plant leaves when the transpiration rate is not measured can be expressed by the following equation (7).

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[0060] The diffusion conductance (g fc ) can be, for example, a value calibrated by an existing measurement method. In addition, in this specification, the term "diffusion conductance" refers to the ease of diffusion of a molecule (e.g., carbon dioxide) in a certain system (e.g., the permeable membrane (12)), and is expressed as the reciprocal of the diffusion resistance.

[0061] According to the biological information measuring device (1) of this embodiment, as shown in FIG. 2, the concentration of carbon dioxide (C s ) can be measured, and the carbon dioxide concentration (C ex In other words, in this embodiment, the carbon dioxide assimilation rate (A) in the plant leaves (40) when the transpiration rate is not measured can be calculated by the diffusion conductance (g fc ) and the measured carbon dioxide concentration difference (C s -C ex ) and take the product.

[0062] Next, the carbon dioxide concentration in the leaves (C i Here, the calculation of the carbon dioxide concentration (C) in the second space (60) measured by a sensor inside the second container (20) will be described. i(m)) is expressed as the leaf carbon dioxide concentration (C i )

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[0063] The reason for this is that the carbon dioxide concentration in the leaves (C i ) and the concentration of carbon dioxide in the second container (20) (C i(m) ) reaches an equilibrium state after a predetermined time has elapsed. The predetermined time is not particularly limited, but it can be determined that equilibrium has been reached when, for example, the measurement value of the sensor (30c) inside the second container (20) becomes constant and stable.

[0064] Furthermore, in the above case, the water vapor conductance (g sw ) can be expressed by the following equation (9).

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[0065] Here, 1.6 and 1.37 in equation (9) are the diffusion ratios of carbon dioxide and water vapor in the air and the boundary layer, respectively. Also, the boundary layer conductance (g bw) is a value that varies depending on the vital information measuring device (1) used, but for example, it is a value measured based on the method of Non-Patent Document 2 (for example, in the vital information measuring device according to the following example, g bw =1.4molm -2 s -1 ) can be used.

[0066] In addition, when the transpiration rate in the above formula (9) is not measured, the carbon dioxide conductance (g c ) can be expressed by the following equation (10).

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[0067] As described above, according to the biological information measuring device (1) of the present embodiment, based on the measurement results obtained only from the sensors (30a, 30b, 30c) that measure the concentration of carbon dioxide, it is possible to obtain biological information of the plant, such as the carbon dioxide assimilation rate (A) in the leaves of the plant and the water vapor conductance (g sw ), and leaf carbon dioxide concentration (C i ) can be easily calculated, but the plant biological information is not limited to those mentioned above.

[0068] In this embodiment, the vital information measuring device (1) may further include, in addition to the sensors (30a, 30b, 30c) that measure the concentration of carbon dioxide, at least one of a sensor that measures the concentration of water vapor and a leaf temperature sensor that measures the temperature of plant leaves, although these are not shown in the figure.

[0069] In this embodiment, the biological information measuring device (1) may further include a calculator (not shown) for calculating biological information of the plant. The calculator calculates, for example, the difference in carbon dioxide concentration (C s -C ex ) and permeability resistance (g fc ) from the above formula (7). In addition, the calculator can calculate the carbon dioxide assimilation rate (A) in the leaves of the plant based on the calculated carbon dioxide assimilation rate (A) in the leaves of the plant and the carbon dioxide concentration (C i(m) ) and the carbon dioxide conductance (g c ) was calculated, and then the carbon dioxide conductance (g c ) and the boundary layer conductance of the plant leaf to water vapor (g bw ) and the water vapor conductance (g sw ) can be calculated.

[0070] (Method of measuring biological information) As described above, FIG. 2 is a side view for explaining a typical example of use of the vital information measuring device (1), and is also a side view for explaining a typical method of measuring vital information according to this embodiment. As shown in FIG. 2, the method of measuring vital information according to this embodiment includes a step of forming a first space (50), a step of forming a second space (60), and a step of measuring a carbon dioxide concentration (C ex (C a equivalent to), C s (C out equivalent to Ci (m) ), calculating the carbon dioxide assimilation rate (A), and measuring the water vapor conductance (g sw )

[0071] In this embodiment, the method for measuring biological information is directed to measuring biological information of a plant having bifacial stomata leaves (40) as shown in Fig. 2. Furthermore, terms common to the method for measuring biological information according to this embodiment and the description of the biological information measuring device (1) have the same meaning.

[0072] In this embodiment, the step of forming the first space (50) is a step of covering at least a portion of one side of a plant leaf (40) having double-sided pores with a first container (10) made of a permeable membrane (12) having at least a portion resistance to permeation of carbon dioxide, as shown in FIG. 2, to form the first space (50) by the first container (10) and the leaf (40). The permeable membrane (12) may have a plurality of holes (represented by a dashed line in the permeable membrane (12) in FIG. 2 for convenience of illustration). According to this measurement method, as shown in FIG. 2, since carbon dioxide can permeate while having a predetermined permeation resistance, the air inside the first space (50) can be released to the outside air, and the biological activity of the plant can be prevented from being hindered. In addition, the concentration difference (C s -C ex ) can be used to calculate the rate of carbon dioxide assimilation in plant leaves (A).

[0073] In this embodiment, the step of forming the second space (60) is a step of covering at least a portion of the other surface of the plant leaf (40) with the second container (20) to form the second space (60).

[0074] In this embodiment, the concentration of carbon dioxide (C ex , C s , Ci (m) The step of measuring the concentration of carbon dioxide (C ex ) and the concentration of carbon dioxide outside the first space (50) (C s ) and the concentration of carbon dioxide (C i(m)) and the step of measuring the concentration of carbon dioxide. More specifically, the concentration of carbon dioxide (C ex , C s , Ci (m) ) can be measured by a normal method using, for example, sensors (30a, 30b, 30c) that measure the concentration of carbon dioxide, as shown in Fig. 2. The sensors (30a, 30b, 30c) that measure the concentration of carbon dioxide are provided, for example, inside and outside the first container (10) and inside the second container (20) as shown in Fig. 2, but there are no limitations on the installation positions as long as the carbon dioxide concentrations inside and outside the first space (50) and inside the second space (60) can be measured.

[0075] In this embodiment, the step of calculating the assimilation rate (A) of carbon dioxide is carried out by calculating the concentration difference (C s -C ex This is a step of calculating the carbon dioxide assimilation rate (A) in the leaves of the plant based on the carbon dioxide assimilation rate (A) and the permeation resistance. The calculation of the carbon dioxide assimilation rate (A) will be described later.

[0076] In this embodiment, the water vapor conductance (g sw The step of calculating the assimilation rate (A) of carbon dioxide and the concentration (C) of carbon dioxide in the second space (60) is carried out by i(m) ) and the water vapor conductance (g sw ) is calculated.

[0077] Hereinafter, the calculation of the plant's biological information by the biological information measuring method according to this embodiment will be briefly described with reference to Fig. 2. The following will focus on the differences from the calculation by the biological information measuring device (1) described above.

[0078] The carbon dioxide assimilation rate (A) in the leaves of a plant is, for example, a concentration difference (C) between the inside and outside of the first space (50) of carbon dioxide measured by the sensors (30a, 30b) as shown in FIG. s-C ex ) and permeability resistance (g fc In this embodiment, the carbon dioxide concentration (C s )" refers to the "concentration of carbon dioxide (C s )" and "the concentration of carbon dioxide in the first container (10) (C ex )" refers to the "concentration of carbon dioxide (C ex )".

[0079] The carbon dioxide concentration (C i(m) ) is the carbon dioxide concentration in the leaf (C i In this embodiment, in the formula (8), the term "the concentration of carbon dioxide in the second container (20) (C i(m) " refers to the concentration of carbon dioxide (C i(m) )".

[0080] Water vapor conductance (g sw ) is calculated based on the carbon dioxide assimilation rate (A) in the leaves of the plant and the carbon dioxide concentration (C) in the second space (60), as shown in FIG. i(m) In this embodiment, the carbon dioxide concentration (C ex )" refers to the "concentration of carbon dioxide (C ex )".

[0081] As described above, according to the method for measuring biological information of the present embodiment, the concentration of carbon dioxide (C ex , C s , C i(m) By measuring only the amount of carbon dioxide assimilation in the leaves (A), water vapor conductance in the stomata (g sw), and leaf carbon dioxide concentration (C i ) can be easily calculated, but the plant biological information is not limited to those mentioned above.

[0082] In this embodiment, the carbon dioxide assimilation rate (A) and the water vapor conductance (g sw ) may be calculated by a computer. EXAMPLES

[0083] Hereinafter, examples will be described in detail for explaining the biological information measuring device and the biological information measuring method according to the present invention. Specifically, in the present embodiment, the measuring method according to the present invention (open diffusion system and C i Direct measurement (hereinafter referred to simply as "OD-E") and conventional measurement methods (open ventilation system and C i In order to simultaneously evaluate and compare the OF with the computational measurement (hereinafter, also referred to simply as "OF"), a vital sign measuring device was constructed as described below.

[0084] (Bio-information measuring device) FIG. 3 is a schematic diagram for explaining a vital information measuring device according to an embodiment. As shown in FIG. 3, the vital information measuring device is a system (an open diffusion system and a C i The system is made up of a direct measurement system and a conventional ventilation system (open ventilation system). In the open ventilation system, the carbon dioxide concentration in the leaves (C i) is calculated based on various measurements made by the system. Specifically, the bioinformation measuring device was assembled by improving the Plant Photosynthesis Comprehensive Analysis System LI-6800 (LI-COR). First, the lower jaw of the chamber (assimilation cuvette) of the Plant Photosynthesis Comprehensive Analysis System LI-6800 was removed and replaced with a container (cup) that covered the same area as the measurement of one side of the plant leaf. Next, the main body part that was connected to the lower jaw of the chamber was blocked off with a rubber sheet (shown in black in Figure 3). In addition, the sample gas measuring section (sample) of the CO2 / H2O analyzer LI-7000 (LI-COR) was inserted into the space (extra volume) formed by the impermeable acrylic container, the permeable membrane, and the plant leaf, and the water vapor concentration (W ex ) and carbon dioxide concentration (C ex ) was connected so that it could measure the carbon dioxide concentration in the space formed by the container and the leaf. Furthermore, the reference gas measurement section (reference) of the CO2 / H2O analyzer LI-7000 was connected to the gas analyzer of the plant photosynthesis comprehensive analysis system LI-6800. Finally, three holes were drilled in the bottom of the cup, and the CO2 / H2O analyzer LI-850 (LI-COR) was connected in a closed loop through two of the holes so that it could measure the carbon dioxide concentration in the space formed by the container and the leaf, and the leaf temperature was measured through one of the holes using the leaf temperature sensor (thermocouple) of the LI-6800. The arrows in Figure 3 indicate the flow of gas.

[0085] (permeable membrane) The permeable membranes used were selected from nylon mesh 508 / 585 (mesh size 5 μm, opening rate 2%, thread diameter 30 / 38 μm), nylon mesh 520 / 560 (mesh size 12 μm, opening rate 11%, thread diameter 30 μm), nylon mesh 508 (mesh size 20 μm, opening rate 16%, thread diameter 30 μm), nylon mesh 330 (mesh size 40 μm, opening rate 26%, thread diameter 38 μm), and nylon mesh 254 (mesh size 70 μm, opening rate 49%, thread diameter 30 μm).

[0086] (Diffusion conductance of permeable membrane) The diffusion conductance (g fc) and the diffusion conductance for water vapor (g fw ) were calibrated values. Specifically, the carbon dioxide assimilation rate (A) and carbon dioxide concentration in the leaf (C i ) and the conductance (g fc , g fw ) was calibrated for each measurement using an open ventilation system. i The conductance (g) of permeable membranes used in the detection of leaf senescence by measurement fc , g fw The calibrated value was used as is. Furthermore, the conductance (g fc , g fw The conductance (g fc , g fw ) are summarized in Tables 1 to 3 below.

[0087] [Table 1]

[0088] [Table 2]

[0089] [Table 3]

[0090] (plant) Sunflowers were used that were grown in pots under the following laboratory conditions: Sunflower leaves have bilateral stomata. Lab environment: Room temperature: 25℃ Day length: 11h light / 13h dark Light source: Red, blue, and white LED (FD8000; Phlizon Technology Co, Ltd., China) Photosynthetically Active Radiation (hereinafter referred to as "PAR"): 1000mmolm -2 s -1 (at plant height) Watering: Before the light period Liquid fertilizer: 357μmolmol -1 N (Peters Professional 20-20-20 General Purpose; ICL Specialty Fertilizers, USA) twice a week

[0091] (A) Carbon dioxide assimilation rate and leaf carbon dioxide concentration (C i ) and biochemical parameters of photosynthesis (V cmax , J max Calculation of A nylon mesh 508 (opening ratio 16%) was used as the permeable membrane for the vital sign measuring device. First, the carbon dioxide assimilation rate (A) of the sunflower leaf and the carbon dioxide concentration (C) in the leaf were measured. i ) was measured as follows. Specifically, the front and back of the sunflower leaf were covered with a window (3 cm x 3 cm) in the chamber of the vital sign measuring device so that the front of the sunflower leaf faced the assimilation cuvette. Next, the LED light source LI-6800-02 (LI-COR), an accessory of the plant photosynthesis comprehensive analysis system LI-6800, was placed so that it overlapped with the top side of the assimilation cuvette. Using this LED light source LI-6800-02, the photosynthetically active radiation (hereinafter referred to as "PAR (μmolm -2 s -1 ) at 800 μmol m -2 s -1 The carbon dioxide concentration (C r ) to control the carbon dioxide concentration (C s ) was changed. The water vapor concentration (W ex ) and carbon dioxide concentration (Cex ) was measured. In addition, the gas analyzer of the plant photosynthesis analysis system LI-6800 was used to measure the water vapor concentration (W r ) and carbon dioxide concentration (C r ) and the water vapor concentration in the air leaving the chamber (W s ) and carbon dioxide concentration (C s ) and the water vapor concentration in the air leaving the chamber (W s ) and carbon dioxide concentration (C s ) was also measured by the CO2 / H2O analyzer LI-7000. i The carbon dioxide concentration (C i(m) ) was measured.

[0092] In the measurement method according to the present invention (OD-E), the carbon dioxide assimilation rate (A) in sunflower leaves was measured using a nylon mesh of 508 g fc (=632mmolm -2 s -1 ) and carbon dioxide concentration (C s , C ex ) was calculated from the above formula (7). In addition, in the measurement method according to the present invention, the carbon dioxide concentration (C i(m) ) is the carbon dioxide concentration in the sunflower leaf (C i ) was treated as

[0093] On the other hand, in the conventional measurement method (OF), the transpiration rate (E) of the sunflower leaf is first calculated by multiplying the flow rate of air entering the chamber (μ r ) and the water vapor concentration in the air entering the chamber (W r ) and the water vapor concentration in the air leaving the chamber (W s ) and compare the measured value with the leaf area (S l The carbon dioxide assimilation rate (A) in the sunflower leaves was calculated using the above formula (1) based on the carbon dioxide concentration (Cr ) and the carbon dioxide concentration in the air leaving the chamber (C s ) and the above-mentioned measured value (μ r , W r , W s ) and these measurements (C r , C s ) and leaf area (S l ) was calculated using the above formula (2). In addition, the water vapor conductance (g w ) is the saturated water vapor concentration (W i ) and the measured water vapor concentration in the leaf atmosphere (W ex ) and the water vapor concentration (W i , W ex The water vapor conductance (g) in the stomata of the plant leaves was calculated based on the average value of the water vapor conductance (g) and the calculated transpiration rate (E) using the above formula (3). sw ) to the calculated value (g w ) and the boundary layer conductance of the plant leaf to water vapor (g bw ) was calculated using the above formula (4). bw is the value measured by the method of Non-Patent Document 2. bw =1.4molm -2 s -1 In addition, the carbon dioxide conductance (g c ) to the calculated value (g sw ) and the measured value (g bw ) was calculated using the above formula (5). Note that in the above formula (5), g bw is the value measured by the method of Non-Patent Document 2. bw =1.4molm -2 s -1 Finally, the above calculated value (g sw ) and the above measured value (g bw ) and the carbon dioxide conductance (g c ) is calculated. Then, the calculated value (g c ) and the carbon dioxide concentration in the air leaving the chamber (Cs Based on the measured value of the carbon dioxide concentration (C), the calculated transpiration rate (E), and the calculated carbon dioxide assimilation rate (A), the carbon dioxide concentration (C) in the sunflower leaf was calculated using the above formula (6). i ) was calculated (Non-Patent Document 1).

[0094] The above measurements were carried out in the same manner, except that the nylon mesh 508 (opening rate 16%), which is the permeable membrane of the vital sign measuring device, was changed to nylon mesh 508 / 585 (opening rate 2%), nylon mesh 520 / 560 (opening rate 11%), nylon mesh 330 (opening rate 26%), and nylon mesh 254 (opening rate 49%). The measurement results are shown in Figure 4.

[0095] Figure 4 shows the carbon dioxide concentration in the leaf atmosphere (C ex The assimilation rate of carbon dioxide (A) and the carbon dioxide concentration in the leaf (C i ) is a graph showing the relationship between AC and i Curve and AC by the measurement method according to the present invention (OD-E) i 1 is a graph showing curve measurement results.

[0096] From the results of FIG. 4, the AC calculated by the measurement method according to the present invention (OD-E) and the conventional measurement method (OF) i The accuracy of the curve was confirmed to be good. i ) is the same as the conventional measurement method (OF) i Even if it is not calculated by calculation, C i C using a direct measurement system i It was found that direct measurement can be performed with sufficient accuracy. Furthermore, except for the case where A was overestimated at the nylon mesh opening rate of 49%, AC was generally good. i It was confirmed that a curve could be obtained.

[0097] Next, the maximum carboxylation reaction rate of Rubisco (V cmax ) and maximum electron velocity (J maxThese biochemical parameters (V cmax , J max ) based on Non-Patent Document 3, AC in FIG. i The curve was fitted with Farquhar's photosynthesis model (also called the "FvCB model") to estimate the results, which are shown in Figure 5. Note that "Rubisco" refers to a CO2 fixation enzyme and is a key enzyme in photosynthetic carbon metabolism. When this Rubisco is inactivated or the Rubisco content in the leaves decreases, V cmax It is known that the amount of V is reduced. Also, Rubisco is an inefficient enzyme, so the leaves cmax It is known that the plant supplies a lot of nitrogen sources to Rubisco in order to increase the plant’s carbon dioxide (CO2) concentration. i ) or strong light conditions, it is known that the rate of carbon dioxide assimilation (A) is the rate limiting factor. On the other hand, the maximum electron transport is related to the light reaction and is known to provide the energy for regeneration of organic matter (RuBP), which is the substrate for Rubisco. In addition, when the carbon dioxide concentration in the leaf is high (C i ) or low light conditions, it is known that it is rate-limiting the rate of carbon dioxide assimilation (A).

[0098] Figure 5 shows the AC i Biochemical parameters of photosynthesis estimated from the curves (V cmax , J max 5. The upper and lower graphs in Fig. 5 show the biochemical parameters (V cmax , J max ) is plotted on the horizontal axis, and the biochemical parameters (V cmax , J max ) is plotted on the vertical axis. Each marker indicates the opening ratio of the nylon mesh used. The diagonal lines sloping upward to the right in the upper and lower parts of Figure 5 indicate a one-to-one relationship.

[0099] As shown in Figure 5, the biochemical parameters of photosynthesis (V cmax , J maxIt was found that the measurement method according to the present invention (OD-E) can estimate the photosynthetic biochemical parameter (V) with accuracy comparable to that of the conventional measurement method (OF). In addition, except for the case where the nylon mesh opening ratio is set to 49% in the measurement method according to the present invention (OD-E), the biochemical parameter (V cmax , J max It was confirmed that the estimation of

[0100] (Detecting sunflower leaf senescence) A nylon mesh 330 (opening ratio 26%) was used as the permeable membrane of the bioinformation measuring device. This bioinformation measuring device was used to measure the carbon dioxide assimilation rate (A) and carbon dioxide concentration (C) in the sunflower leaf. i ) and AC i Specifically, the relationship between the new leaves at the top of the sunflower (leaf order = 1) and the old leaves at the bottom (leaf order = 10) was plotted as C r 500 μmol -1 The other conditions are as above. i The measurement was performed in the same manner as in the previous measurement, and the measurement results are shown in Figure 6.

[0101] FIG. 6 shows AC measured at different leaf orders by the measurement method (OD-E) according to the present invention. i As shown in Figure 6, the lower the leaf, the lower the carbon dioxide concentration in the leaf (C i ) versus carbon dioxide assimilation rate A (μmol m -2 s -1 This suggests a decrease in photosynthetic metabolic activity in senescent leaves.

[0102] (Water vapor conductance (g sw ) Measurement Using nylon mesh 508 (opening ratio 16%) as the permeable membrane of the vital sign measuring device, the water vapor conductance (g sw) was measured as follows. First, watering of sunflowers grown in pots in a laboratory environment was stopped to induce soil drying by evapotranspiration. The weight of the pot containing the plant and soil was measured using a weighing scale before and after the light period from the day before watering was stopped (hereinafter referred to as "day 0"), and the amount of evapotranspiration (g) was calculated from the weight loss. In addition, the soil was saturated, i.e., re-watered, immediately after the light period on the fourth day after watering was stopped (hereinafter referred to as "day 4") (this re-watering is shown as "irrigation" above the number of days after watering was stopped in Figure 7). The amount of evapotranspiration (g) was calculated up to the fifth day after watering was stopped (hereinafter referred to as "day 5"). Furthermore, during the above measurement period (day 0 to day 5), the front and back of the sunflower leaves were covered with the chamber window (3 cm x 3 cm) of the vital sign measuring device so that the front of the sunflower leaves faced the assimilation cuvette, and the AC i The measurement was carried out in the same manner.

[0103] The water vapor conductance (g sw First, the calculated carbon dioxide assimilation rate (A) and the measured carbon dioxide concentration in the extra volume (C ex ) and the carbon dioxide concentration (C i(m) ) and the carbon dioxide conductance (g c ) was calculated. Then, the calculated value (g c ) and the boundary layer conductance of the leaf to water vapor (g bw ) is 1.4 mol m -2 s -1 Based on the above equation (9), the water vapor conductance (g sw ) was calculated.

[0104] On the other hand, the conventional measurement method (OF) was used to measure the water vapor conductance (g sw ) was calculated as described above.

[0105] Figure 7 is a graph showing the time course of evapotranspiration (g) of the sunflower pot soil. In Figure 7, the white background shows the daytime results, and the gray background shows the nighttime results. As shown in Figure 7, it was confirmed that about 500g of water was lost from the pot every day (about 400g during the day and about 100g at night) until the second day after irrigation was stopped. This is thought to be due to evaporation from the sunflower leaves. It was confirmed that the amount of evapotranspiration (g) significantly decreased from the third day after irrigation was stopped, and the daytime amount of evapotranspiration was about 50g on the fourth day after irrigation was stopped. On the other hand, it was confirmed that the daytime amount of evapotranspiration recovered to about 160g and the nighttime amount of evapotranspiration recovered to about 50g on the day after re-irrigation.

[0106] Figure 8 shows the water vapor conductance (g sw ) during the day and at night (days 2 to 5). The upper part of FIG. 8 shows the daytime g sw The lower part of Fig. 8 shows the daily variation of g sw As shown in the upper part of Fig. 8, it was confirmed that the stomata of sunflower leaves tended to close during the day due to the effects of water deprivation. It was also confirmed that the stomatal closure was partially alleviated after watering (day 5). On the other hand, as shown in the lower part of Fig. 8, at night, the water vapor conductance (g sw ) was confirmed to decrease.

[0107] Therefore, the results of Figures 7 and 8 show that sunflowers are stressed by drought, and the water vapor conductance (g sw ) was confirmed to be useful as biological information for plants.

[0108] As described above, the biological information measuring device according to the embodiment can measure the carbon dioxide assimilation rate (A) of the leaves of a plant having leaves with bifacial stomata, such as sunflowers, and the water vapor conductance (g sw ), and leaf carbon dioxide concentration (C i It was confirmed that the biological information of various plants, including plants such as cereals and vegetables, can be easily measured using the simple system (OD-E) of the present invention, without using the conventional system (OF) with a complex configuration. [Explanation of symbols]

[0109] 1. Biometric measuring device 10 1st container 11. Wall 12 Permeable membrane (transparent material) 20 Second container 30a, 30b, 30c 40 leaves 41 Stoma 50 1st space 60 2nd space

Claims

1. a first container for covering at least a portion of one side of a bifacial plant leaf; a second container for covering at least a portion of the other surface of the leaf of the plant; sensors provided inside and outside the first container and inside the second container for measuring a concentration of carbon dioxide; A vital information measuring device, wherein at least a portion of a wall constituting the first container is made of a permeable material having resistance to permeation by carbon dioxide.

2. Calculating an assimilation rate of carbon dioxide in the leaves of the plant based on the carbon dioxide concentration difference between the first container and the outside of the first container and the permeation resistance; 2. The biological information measuring device according to claim 1, further comprising a calculator for calculating water vapor conductance in stomata of the leaves of the plant based on the carbon dioxide assimilation rate and the carbon dioxide concentration in the second container.

3. The biological information measuring device according to claim 1 , wherein the second container covers a surface of the plant leaf opposite to a surface covered by the first container.

4. 4. The biological information measuring device according to claim 1, wherein the transparent material has a plurality of holes.

5. A step of covering at least a portion of one side of a leaf of a double-sided stomata plant with a first container, at least a portion of which is made of a permeable material having permeation resistance to carbon dioxide, to form a first space between the first container and the leaf; covering at least a portion of the other of the leaves of the plant with a second container to form a second space; Measuring concentrations of carbon dioxide inside and outside the first space; Measuring a concentration of carbon dioxide within the second space; Calculating the assimilation rate of carbon dioxide in the leaves of the plant based on the measured carbon dioxide concentration difference between the inside and the outside of the first space and the permeation resistance; A method for measuring biological information comprising a step of calculating water vapor conductance in the stomata of the leaves of the plant based on the carbon dioxide assimilation rate and the carbon dioxide concentration inside the second space.

6. The method for measuring biological information according to claim 5 , wherein the second container covers a surface of the plant leaf opposite to a surface covered by the first container.

7. The method for measuring biological information according to claim 5 or 6, wherein the transmitting material has a plurality of holes.

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