Method for representing electrical bitaxis of plant root system and application of method

Abstract

The invention relates to the technical field of plant electrical response, in particular to a method for representing electrical bitaxis of a plant root system and application thereof.The method comprises the steps that two metal plates are inserted into the two sides of a cuboid water tank in parallel, the two metal plates are connected with the positive electrode and the negative electrode of a direct-current power source respectively, and a culture medium is added into the water tank to form a closed loop; the seeds are placed on sponge and covered with double-layer gauze, and then the sponge is placed in a culture medium of a water tank to culture the seeds; by adjusting the intensity of voltage applied to the two sides of the culture medium and the intensity of current flowing through the culture medium, roots grown from the seeds grow towards the cathode and the anode, so that the electric bitaxis of the plant roots is represented. The method is simple, easy to operate and convenient to observe, the electrical bitaxis of the plant root system can be clearly represented, the electrical response conditions and the electrical response characteristics during the electrical bitaxis can be reflected, and the method has a wide application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of plant electrical response, and in particular to a method for characterizing the electrical diphotaxis of plant roots and an application thereof. Background Art

[0002] Electrotaxis is the tropism of organisms to grow or migrate in response to an external electric field. The phenomenon of roots growing in the direction of an electric field was first observed in the late 19th century, and since then, there have been only sporadic reports in the literature. In either case, the electrotaxis reported so far is unidirectional and does not reflect the range and characteristics of the organism's electrical response. At the same time, based on the fact that all cellular organisms have an electron transport chain and all cellular organisms need to obtain electron donors and electron acceptors from the environment to survive, all cellular organisms should have an innate bidirectional tendency to electron donors and electron acceptors. However, there is currently no method to characterize this behavior of organisms. Summary of the invention

[0003] The purpose of the present invention is to provide a method for characterizing the electroditropism of plant roots and its application.

[0004] The technical solution is as follows:

[0005] The present invention provides a method for characterizing the electro-bitropism of plant roots, comprising the following steps:

[0006] S1, insert two metal plates in parallel on both sides of a rectangular water tank, the two metal plates are respectively connected to the positive electrode and the negative electrode of a DC power supply, add a culture matrix into the water tank to form a closed loop, place seeds on the sponge and cover it with a double layer of gauze, and then place the sponge into the culture matrix of the water tank to culture the seeds;

[0007] S2, by adjusting the voltage intensity applied to both sides of the culture matrix and the current intensity flowing through the culture matrix, the roots grown from the seeds grow toward the cathode and anode directions, thereby characterizing the electrical bitropism of the plant roots.

[0008] Furthermore, the voltage intensity and current intensity adjusted in step S2 are voltage intensity and current intensity at which plant roots can grow.

[0009] Furthermore, the metal plate is made of stainless steel.

[0010] Furthermore, the material of the water tank is light-transmissive, making it easy to observe the growth status of plant roots.

[0011] Furthermore, the water tank is made of a transparent organic board.

[0012] The present invention also includes the application of any of the above-mentioned methods in the biological field, which includes one or more of environmental biology, developmental biology, bioelectrochemistry, bioelectrophysiology, and biological evolution.

[0013] Further, (1) by adjusting the voltage intensity applied to both sides of the culture matrix, the voltage range in which the plant roots grow toward the cathode is determined;

[0014] (2) within the determined voltage range, any voltage is selected as a fixed voltage, and the current intensity is adjusted by changing the conductivity of the culture matrix under the fixed voltage to determine the current range when the roots tend toward the cathode and the anode respectively;

[0015] (3) Count the percentage of roots in the positive and negative directions of the plant root system under different current intensities at a fixed voltage, and based on the obtained data, establish a two-dimensional coordinate system that can show the change of root tropism with current;

[0016] The two-dimensional coordinate system reflects the electrical response characteristics of the corresponding plant root system, and is used to reflect the differences between species corresponding to the plant root system and the growth and development status of the species.

[0017] Furthermore, the x-axis of the two-dimensional coordinate system is the growth direction of the roots. A positive value indicates that the roots grow toward the anode, and a negative value indicates that the roots grow toward the cathode. The value of the x-axis represents the percentage of the number of roots of the plant system in that direction. The y-axis represents the current size. The values ​​under fixed voltage conditions are connected, and the line reflects the degree of change in the root tendency as the current changes under the same voltage conditions.

[0018] Compared with the prior art, the method of the present invention is simple, easy to operate and observe, can clearly characterize the electroditropism of plant roots, and can reflect the electrical response conditions and electrical response characteristics during electroditropism. It has broad application prospects in environmental biology, developmental biology, bioelectrochemistry, bioelectrophysiology, biological evolution and other fields.

[0019] Instruction Manual

[0020] Figure 1 FIG. 4 is a diagram of an experimental device used in an embodiment.

[0021] Figure 2 This is a graph showing the results of plant root electrotropism under different currents in an embodiment.

[0022] Figure 3 These are the electrical characteristics of wheat roots. DETAILED DESCRIPTION

[0023] The technical scheme of the present invention is further described below in conjunction with specific examples. It should be understood that the following examples are only exemplary descriptions and explanations of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are included in the scope that the present invention is intended to protect.

[0024] Example 1

[0025] A method for characterizing the electroditropism of plant roots comprises the following steps:

[0026] S1, insert two stainless steel plates in parallel on both sides of the rectangular transparent organic board water tank, the two stainless steel plates are respectively connected to the positive and negative electrodes of the DC power supply, add distilled water into the water tank to form a closed loop, place the seeds on the sponge and cover it with a double layer of gauze, and then put the sponge into the distilled water in the water tank to culture the seeds;

[0027] S2, by adjusting the voltage intensity applied to both sides of the culture matrix, determine the voltage range in which the roots growing from the seeds show cathodic tendency;

[0028] S3, select any voltage value within the above voltage range, at this voltage value, change the conductivity of the culture matrix to adjust the current intensity, determine the current range A1 in which the roots grown from the seeds show an anode-biased tropism and the current range A2 in which the roots show a cathode-biased tropism, the current range between A1 and A2 is the current range in which the roots show a dual tropism at this voltage value.

[0029] Example 2

[0030] Voltage conditions that characterize wheat roots showing cathodic tropism

[0031] The voltage conditions for characterizing the cathodic tendency of wheat roots were carried out as follows:

[0032] (1) See Figure 1 , wheat (Yannong No. 19) seeds were evenly placed on 6 sponges with a thickness of 2 cm, with a spacing of 1 cm between adjacent seeds. They were covered with double-layer gauze and placed in 6 water tanks (30×10×10 cm). The culture medium of the 6 water tanks was 1L of distilled water.

[0033] (2) Two stainless steel plates (10×10×0.1 cm) were inserted in parallel at both ends of each water tank, and then connected to the anode and cathode of the electrophoresis instrument respectively. The water tank voltage was controlled by the electrophoresis instrument, and the set voltages of the five water tanks were 1V, 5V, 10V, 20V, and 30V, respectively. The remaining treatment group was not powered on and served as a control.

[0034] (3) After 6 days of incubation at 20±0.1℃ in the dark, record the root tropism:

[0035] The number of roots growing toward the cathode and the anode in the control group was the same. When the applied voltage was 1V, the root growth direction was not affected. When the applied voltage was 5V, 80% of the roots were observed to grow toward the cathode. When the applied voltage was 10V, all the roots were observed to grow toward the cathode. When the applied voltage was 20V, all the roots were observed to grow toward the cathode, but the root growth was significantly inhibited. When the applied voltage was 30V, the roots were severely inhibited and could not grow normally. Therefore, the voltage condition for wheat roots to show cathode-oriented behavior is 5-20V.

[0036] Example 3

[0037] Current ranges characterizing the cathodic and anodic tropism of wheat roots

[0038] The current ranges for characterizing the cathodic and anodic tropism of wheat roots were performed as follows:

[0039] (1) Wheat (Yannong No. 19) seeds were evenly placed on 6 sponges with a thickness of 2 cm, with a spacing of 1 cm between adjacent seeds. They were covered with double-layer gauze and placed in 6 water tanks (30×10×10 cm). Mixtures with different conductivity were prepared by changing the ratio of distilled water and tap water. The culture matrix of the 6 water tanks was 1L of distilled water, distilled water, mixture 1 of distilled water and tap water, mixture 2 of distilled water and tap water, mixture 3 of distilled water and tap water, and tap water.

[0040] (2) Two stainless steel plates (10×10×0.1 cm) were inserted in parallel at both ends of each water tank and then connected to the anode and cathode of the electrophoresis apparatus respectively. One of the treatment groups with only distilled water was not energized as a control. The other five groups were all applied with a voltage of 10 V and current intensities of 0.005 mA, 0.3 mA, 0.5 mA, 1 mA, and 2 mA, respectively.

[0041] (3) After 6 days of incubation at 20±0.1℃ in the dark, take photos and record the root tropism.

[0042] The results showed that the amount of growth in the control group towards the cathode and towards the anode was the same; see Figure 2, in the treatment group with a current intensity of 0.005mA, all roots were observed to grow toward the cathode; in the treatment group with a current intensity of 0.3mA, 60% of the roots were observed to grow toward the cathode; in the treatment group with a current intensity of 0.5mA, 80% of the roots were observed to grow toward the anode; in the treatment group with a current intensity of 1mA, all roots were observed to grow toward the anode; in the treatment group with a current intensity of 2mA, all roots were observed to grow toward the anode, and the root growth was significantly inhibited. Therefore, the current condition for the wheat root system to show cathode-oriented behavior is greater than 0-0.3mA (excluding 0), and the current condition for showing anode-oriented behavior is 0.5-2mA. Under the voltage condition of 10V, the electrical equilibrium point of the wheat root system is between 0.3 and 0.5mA.

[0043] Example 4

[0044] Coordinate system drawing of the electrical response characteristics of wheat roots under 10V voltage

[0045] The electrical response characteristic coordinate system of wheat roots under 10V voltage condition is drawn in the following steps:

[0046] (1) Under the condition of 10 V voltage and different current culture environments, the proportion of wheat roots in different growth directions is taken as the value on the corresponding x-axis coordinate, the proportion of roots growing towards the anode is represented by a positive value, and the proportion of roots growing towards the cathode is represented by a negative value;

[0047] (2) The y-axis represents the corresponding current size. Use Excel to draw a graph, add trend lines and fitting formulas. The trend curve of wheat root system under 10V voltage condition with current change is shown in the attached figure. Figure 3 The cathode direction fitting formula is: y = 4E-06x 3 +0.0006x 2 +0.036x+1; the fitting formula for the anode direction is: y=4E-06x 3 -0.0005x 2 +0.0202x+0.005.

[0048] The present invention uses wheat as an example, but the present invention is not limited to wheat, and is also applicable to bean sprouts, rice, flowers, herbs, etc.

[0049] Although the specific implementation modes of the present invention are described above, those skilled in the art should understand that the specific implementation modes described are only illustrative and are not intended to limit the scope of the present invention. Any modifications and changes made by those skilled in the art in accordance with the spirit of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A method for characterizing the electrical diphotaxis of plant roots, characterized in that: The following steps are involved: S1, insert two metal plates in parallel on both sides of a rectangular water tank, the two metal plates are respectively connected to the positive electrode and the negative electrode of a DC power supply, add a culture matrix into the water tank to form a closed loop, place seeds on the sponge and cover it with a double layer of gauze, and then place the sponge into the culture matrix of the water tank to culture the seeds; S2, by adjusting the voltage intensity applied to both sides of the culture matrix and the current intensity flowing through the culture matrix, the roots grown from the seeds grow toward the cathode and anode directions, thereby characterizing the electrical bitropism of the plant roots.

2. A method for characterizing the electrical diphotaxis of plant roots according to claim 1, characterized in that: The voltage intensity and current intensity adjusted in step S2 are voltage intensity and current intensity at which plant roots can grow.

3. A method for characterizing the electrical diphotaxis of plant roots according to claim 1, characterized in that: The metal plate is made of stainless steel.

4. A method for characterizing the electrical diphotaxis of plant roots according to claim 1, characterized in that: The material of the water tank is light-transmissive, which makes it easy to observe the growth status of the plant roots.

5. A method for characterizing the electrical diphotaxis of plant roots according to claim 4, characterized in that: The water tank is made of a transparent organic board.

6. Use of the method according to any one of claims 1 to 5, characterized in that: Application in biological fields, including one or more of environmental biology, developmental biology, bioelectrochemistry, bioelectrophysiology, and biological evolution.

7. The use according to claim 6, characterized in that: (1) By adjusting the voltage intensity applied to both sides of the culture matrix, the voltage range in which the plant roots grow toward the cathode is determined; (2) within the determined voltage range, any voltage is selected as a fixed voltage, and the current intensity is adjusted by changing the conductivity of the culture matrix under the fixed voltage to determine the current range when the roots tend toward the cathode and the anode respectively; (3) Count the percentage of roots in the positive and negative directions of the plant root system under different current intensities at a fixed voltage, and based on the obtained data, establish a two-dimensional coordinate system that can show the change of root tropism with current; The two-dimensional coordinate system reflects the electrical response characteristics of the corresponding plant root system, and is used to reflect the differences between species corresponding to the plant root system and the growth and development status of the species.

8. The use according to claim 7, characterized in that: The x-axis of the two-dimensional coordinate system is the growth direction of the roots. A positive value indicates that the roots grow toward the anode, and a negative value indicates that the roots grow toward the cathode. The value on the x-axis represents the percentage of the number of roots in the plant system in that direction. The y-axis represents the current size. The values ​​under fixed voltage conditions are connected. The line reflects the degree of change in the root tendency as the current changes under the same voltage conditions.

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