CN104502285A - Device and method for detecting content of protein in tomato leaves by multi-angle in situ spectrum - Google Patents

Abstract

The invention relates to the technical field of spectral detection, in particular to a spectral device and method for detecting the protein content of tomato leaves at the tomato planting site. The device includes a spectrum probe, a light source, and an omnidirectional rotator and a light isolation device. The omnidirectional rotator is composed of an arc suspension plate, a circular track plate, an electric drive roller, and a leg. The method includes: (a ) equipment preparation; (b) spectrum whiteboard correction; (c) automatic adjustment of leaf spectrum angle sampling; (d) multi-point sampling of leaf spectrum; (e) physical and chemical value calculation. The invention is erected at the tomato planting site, and can obtain spectral data of the protein content of living tomato leaves; it can measure tomato leaves in all directions and from multiple angles; the electric drive roller rotates automatically, and at the same time, the camera cooperates with observation and monitoring, so the detection efficiency is high.

Description

Device and method for multi-angle in situ spectroscopic detection of protein content in tomato leaves

technical field

The invention relates to the technical field of spectral detection, in particular to a spectral device used for detecting the protein content of tomato leaves at the tomato planting site.

Background technique

Tomato fruit contains a lot of nutrients such as carbohydrates, proteins, amino acids, vitamins and inorganic salts. Therefore, tomatoes are very popular among ordinary people in our country, and the annual output is very large. During the growth of tomato plants, the protein content in the leaves can resist free radicals produced by abiotic stress, provide protection for plants, monitor the protein content indicators during the tomato growth process, analyze the reasons for the changes in the protein content indicators, and provide guidance for tomato planting decisions It provides a scientific basis for the rational water and fertilizer management of tomato planting.

The determination of protein content in tomato leaves is still mainly determined by chemical determination. The use of chemical determination methods is time-consuming and laborious, requires more labor costs, and the analysis process has more mechanical operations, and is generally not suitable for analyzing a large number of samples; chemical analysis requires the use of chemical reagents, which will inevitably pollute the environment. Due to the accuracy of data, convenient operation and environmental protection and non-pollution characteristics, the use of spectroscopy technology to replace conventional chemical analysis methods has been applied to a certain extent.

As shown in Figure 1, due to the different growth forms of tomato leaves, on-site measurement has high requirements on the projection angle of the light source and the incident angle of the spectral probe. Most of the existing tomato leaf protein spectral detection methods use picking new leaves, bagging crushed ice to keep fresh Preventing leaf deterioration from affecting the accuracy of protein spectrum measurement requires high real-time measurement of protein content.

Contents of the invention

In view of the above problems, the object of the present invention is to provide a multi-angle in-situ spectral detection device and method for detecting protein content in tomato leaves, which is suitable for on-site detection and accurate measurement.

In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a multi-angle in-situ spectral detection device for protein content of tomato leaves, including a spectral probe and a light source. The difference is that it also includes an omnidirectional rotator and a light isolation device. The omnidirectional rotator is composed of a circular arc suspension plate, a circular track plate, electric drive rollers, and outriggers. A row of installation holes is uniformly arranged on the arc suspension plate. The light source and the spectral probe select one of them according to the projection angle and incident angle. The installation hole is connected to the arc suspension plate. The two ends of the arc suspension plate are equipped with electric drive rollers. There is an upward groove on the circular track plate. The electric drive roller is embedded in the groove and travels along the groove track. The bottom surface of the track plate is connected with supporting legs; the live tomato plant is in the center of the circular track plate during detection, and the light isolation device covers the omnidirectional rotator together with the live tomato plant under test.

Preferably, the light insulation device includes a light insulation cover and a bracket. The light insulation cover is made of light insulation material, and a wire hole is opened on the top, and the cables and optical fibers of the spectral probe and the light source pass through the wire hole, and the wire hole There is a sealing plug.

Preferably, a camera is also connected to the arc suspension plate.

Preferably, the electrically driven roller consists of a roller and a stepping motor, and the output shaft of the stepping motor is connected to the rotating shaft of the roller.

Preferably, adjustable bolts for adjusting the height of the ring plate from the ground are provided between the legs and the ring plate.

Preferably, the arc suspension plate is in the shape of a semicircle, and the side wall is marked with a scale line indicating the arc angle of the suspension plate.

Preferably, the arc suspension plate has 18 installation holes, and the angle between two adjacent holes is 10°.

Preferably, the light isolation device further includes an electric hoist, a suspension ring is provided on the top of the light isolation cover, the hook of the electric hoist cooperates with the suspension ring, and the electric hoist is suspended on the bracket.

Preferably, the support is a tripod support.

The method for multi-angle in situ spectroscopic detection of tomato leaf protein: comprising the following steps:

(a) Equipment preparation: set up the bracket, lift the light barrier, set up the omnidirectional rotator and level it horizontally. The live tomato plant is in the center of the circular track plate of the omnidirectional rotator. On the arc hanging plate, the cables and optical fibers of the spectral probe and light source pass through the hole, and put down the light shield;

(b) Spectral whiteboard correction: place the whiteboard at the same height as the leaves of the live tomato plant, and perform spectral whiteboard correction;

(c) Automatically adjust and sample the angle of the leaf spectrum: the electric drive roller starts to drive the arc suspension plate together with the spectrum probe and light source to turn a certain angle, and cooperates with the adjustment of the height of the circular track plate, and observes and monitors through the camera to ensure the light at the detection point The angles of incidence and reflection are 90°; the light source sends detection light to the first detection point, and the wavelengths at the detection point are collected by the spectral probe as 690 nm, 850 nm, 992 nm, 1300 nm, 1500 nm, 1600 nm , 1984 nm, 2248 nm and 2304 nm corresponding to the reflectance of tomato leaves;

(d) Multi-point sampling of the leaf spectrum: After the sampling is completed, repeat step (c) to complete the sampling of the other two detection points;

(e) Calculation of physical and chemical values: Input the reflectivity of the three points into the control unit respectively, and the control unit is based on the multiple linear regression equation:

Y=19.852X1+14.478X2+31.258X3-24.334X4+29.374X5-8.698X6+25.698X7+31.258X8-62.365X9+5.39, calculate the protein content of tomato leaves, where Y is the protein content in tomato leaves, X1 ~X9 is the reflectance of tomato live plant leaves corresponding to the wavelengths of 690 nm, 850 nm, 992 nm, 1300 nm, 1500 nm, 1600 nm, 1984 nm, 2248 nm and 2304 nm respectively, three detection points get three proteins Content values, Y1, Y2 and Y3, the sum of Y1, Y2 and Y3 is taken as the average protein content Y in tomato leaves.

The beneficial effects of the present invention have:

(1) The omnidirectional rotator is set up at the tomato planting site, which can obtain the spectral data of the protein content of the living tomato leaves, so as to avoid the inaccurate data of the protein content of the tomato leaves after in vitro.

(2) The circular arc suspension plate is used to rotate horizontally on the circular track plate, and different suspension angles can be selected to measure tomato leaves in all directions and from multiple angles. The spectral projection angle and incidence can be easily changed according to the natural growth form of different tomato leaves. Angle to obtain a better measurement angle.

(3) The adjustable bolt adjusts the height of the ring plate from the ground, which can keep the distance between the spectral probe and the crop relatively constant according to different crop growth heights, so as to obtain better spectral data.

(4) Use a light-shielding cover made of light-shielding material to cover the test instrument together with the crops to be tested, so as to block the influence of the external environment on the spectral data and make the measurement more accurate.

(5) In the case of not lifting the light isolation device, the electric drive roller automatically drives the circular arc suspension plate to rotate horizontally on the circular track plate, and the camera cooperates with observation and monitoring to ensure that the optical path of the detection point is consistent, solving the problem of no electric drive roller and camera It is necessary to lift the light isolation device several times, and the detection efficiency is low.

(6) The whole device is simple and practical, with low cost and easy promotion.

Description of drawings

Fig. 1 is the schematic diagram of tomato leaf;

Fig. 2 is the structural representation of omni-directional rotator in the embodiment of the present invention;

Fig. 3 is a schematic structural diagram of a light-isolation device in an embodiment of the present invention;

Fig. 4 implements and measures tomato leaf protein content result in the embodiment of the present invention;

The marks in the figure indicate: 1—camera, 2—arc suspension plate, 3—spectral probe, 4—groove, 5—circular track plate, 6—electric drive roller, 7—adjustable bolt, 8—outrigger .

Detailed ways

In order to better understand the present invention, the technical solution of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, see Fig. 2, Fig. 3 and Fig. 4:

The multi-angle in-situ spectrum detection device for protein content of tomato leaves implemented by the present invention is mainly used to facilitate on-site erection, and can be applied to different natural growth forms of tomato leaves. Change the spectral projection angle and incident angle to obtain a better measurement angle. The light isolation device blocks the influence of the external environment on the spectral data, and the measurement is more accurate.

The specific structure of the omnidirectional rotator: including the arc suspension plate 2, the circular track plate 5, the electric drive roller 6, the outrigger 8, the arc suspension plate 2 is evenly arranged with a row of installation holes, the spectrum probe 3 and the light source 9 Select one of the mounting holes according to the projection angle and the incident angle, and connect to the arc suspension plate 2 through the light source connection seat 14 and the spectrum probe connection seat 16 respectively. In order to quickly find a better measurement angle, the total number of mounting holes in this embodiment is 18, and the angle between two adjacent holes is 10°. In order to record the comparison measurement results, the semicircular arc hanging plate 2 side wall is marked with a scale line representing the arc angle of the hanging plate. The two ends of the arc suspension plate 2 are equipped with electric drive rollers 6, and the circular track plate 5 is a hollow ring structure, which is provided with a groove 4 with an upward opening. The electric drive roller 6 is embedded in the groove 4 and travels along its track. Push the arc suspension plate 2 together with the spectrum probe 3 to rotate on the plane of the circular track plate 5, and at the same time adjust the incident angle and reflection angle of the light source 9 and the spectrum probe 3 to be 90° through the installation hole of the arc suspension plate 2 to achieve omnidirectional The purpose of multi-angle measurement.

The bottom surface of the ring track plate 5 is connected with supporting legs 8, in order to keep the distance between the spectral probe 3 and the crops relatively constant according to different crop growth heights, so as to obtain better spectral data. In this embodiment, an adjustable bolt 7 for adjusting the height of the circular track plate 5 from the ground is provided between the supporting leg 8 and the circular track plate 5 .

The light insulation device blocks the external ambient light, and the live tomato plant 17 is in the central position of the circular track plate 5 during detection, and the light isolation cover 12 covers the omnidirectional rotator together with the live tomato plant 17 under test. The light isolation device is composed of a light isolation cover 12 and a bracket 10. The light isolation cover 12 is made of a light isolation material, and has a wire hole 11 on the top. The cables and data lines of the spectral probe 3 and the light source 9 pass through the wire hole 11. , The line hole 11 is provided with a sealing plug. The light isolation device also includes an electric hoist 13 , the top of the light isolation cover 12 is provided with a suspension ring, the hook of the electric hoist 13 cooperates with the suspension ring, and the electric hoist 13 is suspended on the support 10 . The support 10 is a tripod support 10 . After the light shield 12 is covered, in order to better understand the internal situation in real time, the camera 1 is installed on the arc suspension plate 2 through the camera connecting seat 15 in this embodiment.

When the embodiment of the present invention works, the method for detecting the protein content of tomato leaves comprises the steps:

(a) Equipment preparation: set up the bracket 10, lift the light barrier 12, set up the omnidirectional rotator and level it horizontally. The hole is installed on the arc suspension plate, the cables and optical fiber lines of the spectral probe and the light source pass through the hole, and the light shield is put down;

(b) Spectral whiteboard correction: place the whiteboard at the same height as the 17 leaves of the live tomato plant, and perform spectral whiteboard correction;

(c) Automatically adjust and sample the angle of the blade spectrum: the electric drive roller 6 starts, drives the arc suspension plate 2 together with the spectrum probe 3 and the light source 9 to turn a certain angle, and adjusts the height of the circular track plate 5 in cooperation with the camera 1 to observe and monitor In order to ensure that the optical path of the detection point is consistent, the incident angle and reflection angle are 90°; the light source 9 sends detection light to the first detection point, and the wavelength at the detection point is collected by the spectral probe 3 as 690 nm, 850 nm, 992 nm, 1300 nm, 1500 nm, 1600 nm, 1984 nm, 2248 nm and 2304 nm correspond to the reflectance of 17 leaves of tomato living plants;

(d) Multi-point sampling of the leaf spectrum: After the sampling is completed, repeat step (c) to complete the sampling of the other two detection points;

(e) Calculation of physical and chemical values: Input the reflectivity of the three points into the control unit respectively, and the control unit is based on the multiple linear regression equation:

Y=19.852X1+14.478X2+31.258X3-24.334X4+29.374X5-48.698X6+25.698

X7+31.258X8-62.365X9+5.39, calculated the protein content of 17 leaves of the tomato live plant, where Y is the protein content in the tomato leaves, X1~X9 are the wavelengths of 690 nm, 850 nm, 992 nm, 1300 nm, and 1500 nm, respectively The reflectance of tomato live plant 17 leaves corresponding to nm, 1600 nm, 1984 nm, 2248 nm and 2304 nm, three detection points to get three protein content values, Y1, Y2 and Y3, sum Y1, Y2 and Y3 Take the average as the protein content Y in tomato leaves.

From a microscopic point of view, the active state of the molecules that make up tomato leaves is excited by the energy of the detected light, resulting in different energy level transitions, absorbing and releasing energy, and forming reflection spectra and absorption spectra corresponding to the molecules. Different chemical bonds, such as O-H, N-H, C-H, etc., the rotation and stretching vibration of chemical bonds, and the transition between energy levels will absorb light of a specific wavelength and excite to produce characteristic peaks. According to the intensity and wave number of the characteristic peaks, the composition of the substance can be judged .

The wavelength used is related to the vibration information of chemical bonds such as NH, CN, and NH in the protein of tomato leaves and related chemical components. These information can reflect the strength of protein content in pear tomato leaves. For example, 690 nm and 850 nm reflect the aromatic hydrocarbon and methyl information of tomato leaf protein, 992 nm reflects the amine information of tomato leaf protein, 1300 nm reflects the group CH ₃ information of tomato leaf protein, and 1500 nm reflects the The group NH ₂ information of the protein, 1600 nm reflects the group ArCH information of the tomato leaf protein, 1984 nm reflects the information of the tomato leaf protein group CONH ₂ and primary amide information, and 2248 nm and 2304 nm reflect the tomato leaf protein group information CH ₂ information. The multiple linear regression algorithm was used to model and analyze the above characteristic wavelengths, and the linear equation between the protein content of tomato leaves and the characteristic wavelengths was established.

The selected characteristic wavelength of the present invention is only for the rapid detection of the protein content of tomato leaves. If other indicators need to be measured, a specific wavelength needs to be selected again, and a model is established through multiple linear regression to calculate the corresponding index value.

Utilize the related indexes of the method provided by the present invention to set up the model to see Table 1, wherein, the modeling set represents when setting up the model, utilizes the reflectance of tomato leaf and the tomato leaf protein content fitting that existing method test obtains to obtain model equation, prediction set It means that when predicting, that is, after the model is established, according to the model equation, the tomato leaf protein content is calculated by substituting the characteristic wavelength reflectance of the tomato leaf spectrum into the model equation.

Table 1

data set Sample size decisive factor Root mean square error (mg/g) modeling set 100 0.8502 3.158 prediction set 40 0.8412 3.214

Example 1~10

Utilize the device and method provided by the invention to test the protein content of tomato leaves, and the test results are shown in Table 2.

Table 2

From the data in Table 2, it can be seen that the protein content of tomato leaves measured by the method of the present invention is close to the data obtained by existing methods, and the present invention can be used to quickly measure the protein content of tomato leaves with reliable results.

Claims (10)

1. multi-angle In situ spectroscopic detects tomato leaf protein content device, include spectroscopic probe head, light source, it is characterized in that, also include all-directional rotation instrument and every electro-optical device, all-directional rotation instrument is by circular arc suspension plate, ring ring plate, electricity drives roller, supporting leg forms, circular arc suspension plate arc uniform arranges row's mounting hole, light source and spectroscopic probe head select one of them mounting hole to be connected in circular arc suspension plate according to crevice projection angle and incident angle respectively, circular arc suspension plate two head end is equipped with electricity and drives roller, ring ring plate is provided with the groove of opening upwards, electricity drives in roller embedding groove and advances along impression orbit, ring ring plate bottom surface is connected with passive supporting leg, during detection, tomato strain alive is in ring ring plate center, is entered wherein by all-directional rotation instrument every electro-optical device together with tested tomato strain cover alive.

2. multi-angle In situ spectroscopic according to claim 1 detects tomato leaf protein content device, it is characterized in that: describedly include light shade cover, support every electro-optical device, light shade cover is made by every luminescent material, top has string holes, cable and the optical fiber cable of spectroscopic probe head and light source pass from string holes, and string holes place is provided with sealing-plug.

3. multi-angle In situ spectroscopic according to claim 1 detects tomato leaf protein content device, it is characterized in that: described circular arc suspension plate is also connected with camera.

4. multi-angle In situ spectroscopic according to claim 1 detects tomato leaf protein content device, it is characterized in that: described electricity drives roller and is made up of roller and stepper motor, and stepper motor output shaft is connected with roller wheel shaft.

5. multi-angle In situ spectroscopic according to claim 1 detects tomato leaf protein content device, it is characterized in that: be provided with the adjustable bolt regulating Circular Plate terrain clearance between described supporting leg and Circular Plate.

6. multi-angle In situ spectroscopic according to claim 1 detects tomato leaf protein content device, it is characterized in that: described circular arc suspension plate semicircular in shape, and is marked with the scale mark representing suspension plate arc angle at sidewall.

7. multi-angle In situ spectroscopic according to claim 1 detects tomato leaf protein content device, it is characterized in that: the mounting hole number of described circular arc suspension plate is 18, and adjacent holes angle is 10 °.

8. multi-angle In situ spectroscopic according to claim 2 detects tomato leaf protein content device, it is characterized in that: describedly also include electric block every electro-optical device, light shade cover top is provided with suspension ring, and the suspension hook of electric block coordinates with suspension ring, and electric block is suspended on support.

9. multi-angle In situ spectroscopic according to claim 2 detects tomato leaf protein content device, it is characterized in that: described support is three-legged support.

10. multi-angle In situ spectroscopic detects the method for tomato leaf protein content, it is characterized in that: comprise the steps:

A () equipment prepares: erection bracket, lifting light shade cover, set up all-directional rotation instrument and level leveling, tomato strain alive is in the ring ring plate center of all-directional rotation instrument, spectroscopic probe head and light source are arranged in circular arc suspension plate respectively by mounting hole, cable and the optical fiber cable of spectroscopic probe head and light source pass from string holes, put down light shade cover;

B () spectrum blank is corrected: blank and the concordant placement of tomato strain blade height alive, carries out the rectification of spectrum blank;

C the angle of () Spectra of The Leaves adjusts sampling automatically: electricity drives roller and starts, circular arc suspension plate is driven to turn over certain angle together with spectroscopic probe head and light source, and coordinate adjustment ring ring plate height, consistent to ensure the light path of check point by camera observation monitoring, incident angle and reflection angle are 90 °; Light source sends to first check point and detects light, and the wavelength utilizing spectroscopic probe head acquisition testing point place is 690 nm, the reflectivity of tomato leaf corresponding to 850 nm, 992 nm, 1300 nm, 1500 nm, 1600 nm, 1984 nm, 2248 nm and 2304 nm;

D the multi-point sampling of () Spectra of The Leaves: after having sampled, repeats step (c), completes the sampling of two other check point;

E () physics and chemistry value calculates: by gained three point reflection rates Input Control Element respectively, control module is according to multiple linear regression equations:

Y=19.852X1+14.478X2+31.258X3-24.334X4+29.374X5-8.698X6+2 5.698X7+31.258X8-62.365X9+5.39, calculate the protein content of tomato leaf, in formula, Y is protein content in tomato leaf, X1 ~ X9 is respectively wavelength 690 nm, 850 nm, 992 nm, 1300 nm, 1500 nm, 1600 nm, 1984 nm, the reflectivity of 2248 nm and the strain blade alive of the tomato corresponding to 2304 nm, three check points obtain three protein content values, Y1, Y2 and Y3, by Y1, Y2 and Y3 summation is made even and is protein content Y in tomato leaf.