Moisture calibration type chlorophyll detection system and method

Abstract

The invention discloses a moisture calibration type chlorophyll detection system and method, and belongs to the technical field of chlorophyll detection, and the system comprises a heating sheet used for heating plant leaves to evaporate moisture; the condensing sheet is used for condensing the evaporated water into liquid drops to obtain condensed water drops; the gravity sensor is used for weighing plant leaves to obtain the weight of the leaves; and the SPAD chlorophyll measuring instrument is used for performing chlorophyll measurement on the plant leaves which reach the target leaf moisture content after moisture evaporation to obtain the relative chlorophyll content of the plant leaves. According to the method, the water content of the plant leaves is rapidly and accurately calibrated based on the system, and the relative chlorophyll content of the plant leaves is measured. The method solves the problem that it is difficult to quickly and accurately calibrate the water content of the plant leaves.

Description

Technical Field

[0001] The invention belongs to the technical field of chlorophyll detection, and in particular relates to a moisture-calibrated chlorophyll detection system and method. Background Art

[0002] Chlorophyll is an important indicator for evaluating the photosynthetic capacity and physiological condition of plants. The SPAD chlorophyll meter can quickly, conveniently and non-destructively test the color of rice leaves, and the use of the SPAD chlorophyll meter to diagnose the nitrogen nutrition of crops has been applied to wheat, corn and rice. It can be seen that analyzing the distribution characteristics of the SPAD value of plant leaves and constructing a nitrogen nutrition diagnosis model based on the SPAD value of plant leaves is of great significance for real-time and field precise regulation of plant nitrogen.

[0003] Existing studies have found that under different soil water stresses, there are significant differences in the chlorophyll content in the leaves of plant seedlings. The chlorophyll content shows a decreasing trend with the decrease in water content. When the soil moisture content in the plant body is 70% to 75% of the maximum field water holding capacity, it is conducive to the synthesis of chlorophyll. Water stress can cause damage to the photosynthetic efficiency of leaves, thereby reducing the photosynthetic products of plants and affecting the function of chlorophyll. Its photosynthetic efficiency will be significantly reduced. Existing studies have shown that as soil moisture increases, the chlorophyll a, chlorophyll b and total chlorophyll content of plants all show a trend of increasing and then decreasing. After the soil is flooded, the photosynthetic rate of waterlogged plants decreases rapidly. Under different water contents of leaves, the chlorophyll content measured by the SPAD chlorophyll meter is also significantly different. The SPAD chlorophyll meter requires accurate leaf moisture to measure accurate leaf chlorophyll values, but it is currently difficult to quickly and accurately determine the moisture content of leaves, and thus difficult to obtain accurate plant chlorophyll values ​​based on accurate leaf moisture information, which seriously affects the optimization of plant photosynthesis and physiological conditions. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention provides a moisture-calibrated chlorophyll detection system and method, which solves the problem of difficulty in quickly and accurately calibrating the moisture content of plant leaves.

[0005] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0006] In one aspect, the present invention provides a moisture calibration chlorophyll detection system, comprising:

[0007] A heating sheet for heating plant leaves to evaporate water;

[0008] A condensing sheet is used to condense the evaporated water into droplets to obtain condensed water drops;

[0009] A gravity sensor is used to weigh the plant leaves to obtain the leaf weight;

[0010] The SPAD chlorophyll meter is used to measure the chlorophyll content of plant leaves that have reached the target leaf moisture content after water evaporation, and obtain the relative chlorophyll content of the plant leaves, wherein the target leaf moisture content is the leaf moisture content data corresponding to the chlorophyll content data of the plant leaves when the chlorophyll content data of the plant leaves is the most stable.

[0011] Furthermore, the moisture-calibrated chlorophyll detection system provided by the present invention also includes a first database for storing chlorophyll content data measured on leaves of different types of plants at different leaf moisture contents, wherein the leaf moisture content is set according to a preset moisture content interval.

[0012] Furthermore, the moisture-calibrated chlorophyll detection system provided by the present invention also includes a data analysis module, which is used to analyze the chlorophyll content data measured of different plant leaves at different leaf moisture contents in the first database to obtain the target leaf moisture content corresponding to when the chlorophyll content data of each type of plant leaves is most stable.

[0013] Furthermore, the moisture-calibrated chlorophyll detection system provided by the present invention also includes a second database for storing target leaf moisture contents of leaves of different types of plants.

[0014] The beneficial effects of the present invention are as follows: a moisture calibration chlorophyll detection system provided by the present invention provides conditions for heating plant leaves and condensing water droplets after heating and evaporation of plant leaves through heating plates and condensation plates, providing a basis for analyzing the moisture content of plant leaves based on the leaf weight and water evaporation weight obtained after weighing by a gravity sensor; the present invention facilitates analysis to obtain the target leaf moisture content corresponding to the most stable chlorophyll content data of various plant leaves by constructing a first database; the present invention obtains the target leaf moisture content corresponding to the most stable chlorophyll content data of various plant leaves through a data analysis module, which facilitates rapid and accurate calibration of the plant leaf moisture content to obtain plant leaves with the target leaf moisture content, greatly improving the accuracy of the relative chlorophyll content of plant leaves measured by a SPAD chlorophyll meter; the present invention facilitates rapid acquisition of the target leaf moisture content of the plant leaves of the type to be measured through a second database, so as to accurately control the heating and water evaporation of the plant leaves and obtain the plant leaves with the target leaf moisture content, thereby realizing efficient use of the SPAD chlorophyll meter to measure accurate relative chlorophyll content of the plant leaves.

[0015] On the other hand, the present invention also provides a moisture calibration chlorophyll detection method, comprising the following steps:

[0016] S1, obtaining a first plant leaf and a second plant leaf that are adjacent to each other on the same plant;

[0017] S2. Weigh the first plant leaf and the second plant leaf respectively using a gravity sensor to obtain an initial weight of the first leaf and an initial weight of the second plant leaf;

[0018] S3, heating the first plant leaf at a preset heating temperature using the heating sheet, and condensing the water evaporated after the first plant leaf is heated using the condensing sheet, until the weight of the first plant leaf is measured by the gravity sensor and no longer changes, thereby obtaining the total water weight of the first leaf;

[0019] S4, obtaining the target leaf moisture content of the leaves of the corresponding plant species of the plant;

[0020] S5, calculating the ratio of the target evaporated water weight to the initial weight of the first leaf according to the total water weight of the first leaf and the target leaf water content of the plant leaves of the corresponding type of the plant, as the evaporation target value;

[0021] S6, heating the second plant leaf according to a preset heating temperature using the heating sheet, and continuously weighing the second plant leaf using the gravity sensor to obtain a real-time weight of the second plant leaf;

[0022] S7, if the ratio of the difference between the initial weight of the second plant leaf and the real-time weight of the second plant leaf and the initial weight of the second plant leaf is equal to the evaporation target value, then stop heating by the heating plate, and take out the heated second plant leaf as the plant leaf with the target leaf moisture content;

[0023] S8. Use a SPAD chlorophyll meter to measure the chlorophyll content of plant leaves with target leaf moisture content to obtain the relative chlorophyll content of the plant leaves.

[0024] Further, the S8 comprises the following steps:

[0025] S81, when the measuring head does not clamp the plant leaf with the target leaf moisture content, sequentially make the red light area LED and the infrared light area LED emit light, and convert the light intensities respectively received by the receiver into a first electrical signal and a second electrical signal;

[0026] S82, when the measuring head clamps the plant leaf of the target leaf moisture content, the red light LED and the infrared light LED are again sequentially illuminated, so that the light transmitted through the plant leaf hits the receiver and is converted into a third electrical signal and a fourth electrical signal accordingly;

[0027] S83. Using a SPAD chlorophyll meter, a SPAD value is calculated based on the first electrical signal, the second electrical signal, the third electrical signal, and the fourth electrical signal as the relative chlorophyll content of the plant leaves.

[0028] The beneficial effects of the present invention are as follows: a moisture-calibrated chlorophyll detection method provided by the present invention is implemented based on the above-mentioned moisture-calibrated chlorophyll detection system, and is used to quickly and accurately calibrate the moisture content of plant leaves, based on the moisture content of plant leaves with the most stable chlorophyll content, that is, the target leaf moisture content, and using a SPAD chlorophyll meter to measure and obtain accurate relative chlorophyll content of plant leaves; the method of the present invention is simple and convenient, and by using the above-mentioned moisture-calibrated chlorophyll detection system, the efficiency and accuracy of accurately calibrating the moisture content of plant leaves are greatly improved.

[0029] Other advantages of the present invention will be analyzed in more detail in subsequent embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 This is a block diagram of a moisture-calibrated chlorophyll detection system in Example 1 of the present invention.

[0032] Figure 2 This is a flow chart of the steps of a moisture calibration chlorophyll detection method in Example 2 of the present invention. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present invention.

[0034] Embodiment 1:

[0035] like Figure 1As shown, on the one hand, in one embodiment of the present invention, the present invention provides a moisture calibration chlorophyll detection system, comprising:

[0036] A heating sheet for heating plant leaves to evaporate water;

[0037] A condensing sheet is used to condense the evaporated water into droplets to obtain condensed water drops;

[0038] The condensation sheet can effectively remove the influence of moisture in the air and prevent the moisture evaporated from plant leaves from damaging the gravity sensor and SPAD chlorophyll meter.

[0039] A gravity sensor is used to weigh the plant leaves to obtain the leaf weight;

[0040] The SPAD chlorophyll meter is used to measure the chlorophyll content of plant leaves that have reached the target leaf moisture content after water evaporation, and obtain the relative chlorophyll content of the plant leaves, wherein the target leaf moisture content is the leaf moisture content data corresponding to the chlorophyll content data of the plant leaves when the chlorophyll content data of the plant leaves is the most stable.

[0041] The SPAD chlorophyll meter calculates the SPAD value based on the amount of light transmitted by the leaf in two different wavelength regions. Chlorophyll has different light absorption in these two wavelength regions, namely the red light region with high light absorption and unaffected by carotene, and the infrared region with extremely low light absorption.

[0042] The SPAD value can reflect the relative content of chlorophyll. The SPAD value can be used to understand the plant's nitro demand and also to calculate the nitrogen fertilizer content.

[0043] Chlorophyll is the main substance that absorbs light. Leaves absorb different amounts of light of different wavelengths. Therefore, this solution determines the relative content of chlorophyll in leaves by measuring the transmittance coefficient within two wavelength ranges. The SPAD chlorophyll meter provided by the present invention, model SPAD-502, evaluates the relative content of chlorophyll in the current plant leaves by measuring the absorption rate of plant leaves in two wavelength bands.

[0044] As a preferred solution, the moisture-calibrated chlorophyll detection system provided by the present invention also includes a first database for storing chlorophyll content data measured on leaves of different types of plants at different leaf moisture contents, wherein the leaf moisture content is set according to a preset moisture content interval.

[0045] In this embodiment, if the table constructed in the first database is a general table of all plant types, the general table includes at least three columns: plant name and serial number, leaf moisture content and chlorophyll content data, wherein the plant name and serial number are primary keys; if the constructed table also includes sub-tables constructed according to plant types, each sub-table is named after the plant name and includes at least three columns: plant serial number, leaf moisture content and chlorophyll content data, wherein the plant serial number is the primary key. By constructing the first database, it is convenient to analyze and obtain the target leaf moisture content corresponding to the most stable chlorophyll content data of the leaves of various types of plants.

[0046] As a preferred solution, the moisture-calibrated chlorophyll detection system provided by the present invention also includes a data analysis module, which is used to analyze the target leaf moisture content corresponding to the most stable chlorophyll content data of various plant leaves based on the chlorophyll content data measured at different leaf moisture contents of different plant leaves in the first database. In this solution, the target leaf moisture content is the average leaf moisture content when the difference in chlorophyll content data corresponding to the moisture content of consecutive adjacent leaves is less than a preset chlorophyll content difference threshold. In this embodiment, the target leaf moisture content is obtained based on the analysis of the moisture content of at least three consecutive adjacent leaves. If there are multiple identical situations, the average leaf moisture content is taken.

[0047] By analyzing the target leaf moisture content corresponding to the most stable chlorophyll content data of various plant leaves, it is convenient to quickly and accurately calibrate the plant leaf moisture content to obtain plant leaves with target leaf moisture content, greatly improving the accuracy of relative chlorophyll content of plant leaves measured by SPAD chlorophyll meter.

[0048] As a preferred solution, the moisture-calibrated chlorophyll detection system provided by the present invention further includes a second database for storing target leaf moisture contents of leaves of different types of plants.

[0049] The second database facilitates the rapid acquisition of the target leaf moisture content of the plant leaves to be measured, so as to accurately control the heating and water evaporation of the plant leaves and obtain the plant leaves with the target leaf moisture content, thereby efficiently utilizing the SPAD chlorophyll meter to measure and obtain accurate relative chlorophyll content of the plant leaves.

[0050] Embodiment 2:

[0051] like Figure 2 As shown, on the other hand, in one embodiment of the present invention, the present invention also provides a moisture calibration chlorophyll detection method, comprising the following steps:

[0052] S1, obtaining a first plant leaf and a second plant leaf that are adjacent to each other on the same plant;

[0053] S2. Weigh the first plant leaf and the second plant leaf respectively using a gravity sensor to obtain an initial weight of the first leaf and an initial weight of the second plant leaf;

[0054] S3, using the heating plate to heat the first plant leaf at a preset heating temperature, and using the condensing plate to condense the water evaporated after heating the first plant leaf, until the weight of the first plant leaf is measured by the gravity sensor and no longer changes, thereby obtaining the total water weight of the first leaf; in this scheme, the total water weight of the first leaf is the difference between the initial weight of the first leaf and the weight of the first plant leaf when the weight no longer changes;

[0055] S4, obtaining the target leaf moisture content of the leaves of the corresponding plant species of the plant;

[0056] S5. According to the total water weight of the first leaf and the target leaf water content of the plant leaves of the corresponding type of the plant, the ratio of the target evaporated water weight to the initial weight of the first leaf is calculated as the evaporation target value; in this scheme, the target leaf water content is equal to the ratio of the difference between the total water weight of the first leaf minus the target evaporated water weight and the difference between the initial weight of the first leaf minus the target evaporated water weight, and the target evaporated water weight can be calculated;

[0057] S6, heating the second plant leaf according to a preset heating temperature using the heating sheet, and continuously weighing the second plant leaf using the gravity sensor to obtain a real-time weight of the second plant leaf;

[0058] S7, if the ratio of the difference between the initial weight of the second plant leaf and the real-time weight of the second plant leaf and the initial weight of the second plant leaf is equal to the evaporation target value, then stop heating by the heating plate, and take out the heated second plant leaf as the plant leaf with the target leaf moisture content;

[0059] S8. Use a SPAD chlorophyll meter to measure the chlorophyll content of plant leaves with target leaf moisture content to obtain the relative chlorophyll content of the plant leaves.

[0060] The S8 comprises the following steps:

[0061] S81, when the measuring head does not clamp the plant leaf with the target leaf moisture content, sequentially make the red light area LED and the infrared light area LED emit light, and convert the light intensities respectively received by the receiver into a first electrical signal and a second electrical signal;

[0062] S82, when the measuring head clamps the plant leaf of the target leaf moisture content, the red light LED and the infrared light LED are again sequentially illuminated, so that the light transmitted through the plant leaf hits the receiver and is converted into a third electrical signal and a fourth electrical signal accordingly;

[0063] S83. Using a SPAD chlorophyll meter, a SPAD value is calculated based on the first electrical signal, the second electrical signal, the third electrical signal, and the fourth electrical signal as the relative chlorophyll content of the plant leaves.

[0064] The following calculation method can be used to calculate the chlorophyll content of plant tissues: chlorophyll content = [relative chlorophyll concentration × extract volume × dilution factor] / sample fresh weight (or dry weight).

[0065] Embodiment 3:

[0066] Based on Example 1, the present invention also provides a real-time method, that is, the moisture-calibrated chlorophyll detection system provided in Example 1 also includes a controller for controlling the heating time of the heating plate so that the plant leaves reach the target moisture content of the plant leaves of this type.

[0067] When the water-calibration chlorophyll detection system has a controller, the water-calibration chlorophyll detection method based on the water-calibration chlorophyll detection system includes the following steps:

[0068] A1. Obtaining a first plant leaf and a second plant leaf that are adjacent to each other on the same plant;

[0069] A2. Weigh the first plant leaf using a gravity sensor to obtain an initial weight of the first leaf;

[0070] A3. Using a heating plate to heat the first plant leaf at a preset heating temperature, and using a condensing plate to condense the water evaporated after heating the first plant leaf, and using a gravity sensor to continuously weigh the first plant leaf during the heating process to obtain the weight of the first leaf at different heating times, and until the weight of the first plant leaf measured by the gravity sensor no longer changes, the total water weight of the first leaf is obtained; in this solution, the total water weight of the first leaf is the difference between the initial weight of the first leaf and the weight of the first plant leaf when the weight no longer changes;

[0071] A4, obtaining the target leaf moisture content of the leaves of the corresponding plant species of the plant;

[0072] A5. Set the target leaf moisture content equal to the ratio of the difference between the total weight of the first leaf moisture and the target evaporated moisture weight to the difference between the initial weight of the first leaf and the target evaporated moisture weight, and calculate the target evaporated moisture weight;

[0073] A6. Calculate the target leaf weight after deducting the target evaporated water weight from the initial weight of the first leaf, and obtain the heating time corresponding to the target leaf weight as the target heating time;

[0074] A7, using a controller to control the heating plate to heat the second plant leaf for a target heating time, stopping the heating plate from heating, and taking out the heated second plant leaf as the plant leaf with the target leaf moisture content;

[0075] A8. Use a SPAD chlorophyll meter to measure the chlorophyll content of plant leaves with target leaf moisture content to obtain the relative chlorophyll content of the plant leaves.

[0076] In this embodiment, the chlorophyll content of plant leaves with target leaf moisture content is measured using a SPAD chlorophyll meter, and the method for obtaining the relative chlorophyll content of the plant leaves is the same as the method in Embodiment 2.

[0077] Adjacent plant leaves of the same plant have the same water evaporation content per unit area and per unit time under the same temperature environment. Therefore, according to the heating time for the first plant leaf to reach the target leaf moisture content, the heating plate can be controlled to heat the second plant leaf for the same length of time, thereby obtaining the plant leaves with the target leaf moisture content, and the chlorophyll content of the plant leaves with the target leaf moisture content can be measured by the SPAD chlorophyll meter to obtain the relative chlorophyll content of the plant leaves.

[0078] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A moisture calibration chlorophyll detection system, characterized in that: include: A heating sheet for heating plant leaves to evaporate water; A condensing sheet is used to condense the evaporated water into droplets to obtain condensed water drops; A gravity sensor is used to weigh the plant leaves to obtain the leaf weight; The SPAD chlorophyll meter is used to measure the chlorophyll content of plant leaves that have reached the target leaf moisture content after water evaporation, and obtain the relative chlorophyll content of the plant leaves, wherein the target leaf moisture content is the leaf moisture content data corresponding to the chlorophyll content data of the plant leaves when the chlorophyll content data of the plant leaves is the most stable.

2. The moisture calibration chlorophyll detection system according to claim 1, characterized in that: It also includes a first database for storing chlorophyll content data measured on leaves of different types of plants at different leaf moisture contents, wherein the leaf moisture content is set according to a preset moisture content interval.

3. The moisture calibration chlorophyll detection system according to claim 2, characterized in that: It also includes a data analysis module for analyzing the chlorophyll content data of different plant leaves measured at different leaf moisture contents in the first database to obtain the target leaf moisture content corresponding to when the chlorophyll content data of various plant leaves is most stable.

4. The moisture calibration chlorophyll detection system according to claim 3, characterized in that: A second database is also included for storing target leaf moisture contents of leaves of different types of plants.

5. The moisture calibration chlorophyll detection system according to claim 1, characterized in that: It also includes a controller for controlling the heating time of the heating plate so that the plant leaves reach the target moisture content of the plant leaves of this type.

6. A moisture calibration chlorophyll detection method, characterized in that: The steps include: S1, obtaining a first plant leaf and a second plant leaf that are adjacent to each other on the same plant; S2. Weigh the first plant leaf and the second plant leaf respectively using a gravity sensor to obtain an initial weight of the first leaf and an initial weight of the second plant leaf; S3, heating the first plant leaf at a preset heating temperature using the heating sheet, and condensing the water evaporated after the first plant leaf is heated using the condensing sheet, until the weight of the first plant leaf is measured by the gravity sensor and no longer changes, thereby obtaining the total water weight of the first leaf; S4, obtaining the target leaf moisture content of the leaves of the corresponding plant species of the plant; S5, calculating the ratio of the target evaporated water weight to the initial weight of the first leaf according to the total water weight of the first leaf and the target leaf water content of the plant leaves of the corresponding type of the plant, as the evaporation target value; S6, heating the second plant leaf according to a preset heating temperature using the heating sheet, and continuously weighing the second plant leaf using the gravity sensor to obtain a real-time weight of the second plant leaf; S7, if the ratio of the difference between the initial weight of the second plant leaf and the real-time weight of the second plant leaf and the initial weight of the second plant leaf is equal to the evaporation target value, then stop heating by the heating plate, and take out the heated second plant leaf as the plant leaf with the target leaf moisture content; S8. Use a SPAD chlorophyll meter to measure the chlorophyll content of plant leaves with target leaf moisture content to obtain the relative chlorophyll content of the plant leaves.

7. The moisture calibration chlorophyll detection method according to claim 6, characterized in that: The S8 comprises the following steps: S81, when the measuring head does not clamp the plant leaf with the target leaf moisture content, sequentially make the red light area LED and the infrared light area LED emit light, and convert the light intensities respectively received by the receiver into a first electrical signal and a second electrical signal; S82, when the measuring head clamps the plant leaf of the target leaf moisture content, the red light LED and the infrared light LED are again sequentially illuminated, so that the light transmitted through the plant leaf hits the receiver and is converted into a third electrical signal and a fourth electrical signal accordingly; S83. Using a SPAD chlorophyll meter, a SPAD value is calculated based on the first electrical signal, the second electrical signal, the third electrical signal, and the fourth electrical signal as the relative chlorophyll content of the plant leaves.

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