Graphene composite anti-freezing agent and anti-freezing method based on flowering state difference of apricot trees

Abstract

The invention discloses a graphene composite anti-freezing agent. The graphene composite anti-freezing agent is prepared by compounding a traditional anti-freezing agent and 3-7mg / L graphene, 30-100 ml of the graphene composite anti-freezing agent is applied to each branch for unbloomed branches of apricot trees in the flower bud stage, 30-100 ml of the graphene composite anti-freezing agent is applied to each branch for bloomed branches of apricot trees in the full-bloom stage, and 30-100 ml of the graphene composite anti-freezing agent is applied to each branch; by adding the graphene solution with proper concentration, the permeability of the traditional antifreezing agent is remarkably enhanced, the uniform distribution of the antifreezing agent in floral organ cells is promoted, the problem that the traditional antifreezing agent only forms a film layer on the surface and cannot penetrate into the cells is avoided, and the effective utilization rate of the antifreezing agent is increased by 15% or above (drug reduction); meanwhile, the activity of superoxide dismutase (SOD) can be improved, active oxygen generated by low-temperature induction is effectively removed, and cell membrane lipid peroxidation is inhibited; the method is suitable for large-scale popularization in mountainous and forest farms, has strong adaptability to environmental conditions such as soil and climate, and is suitable for most apricot producing areas in northern China.

Description

Technical Field

[0001] This invention belongs to the field of agricultural antifreeze technology, specifically relating to a graphene composite antifreeze agent and a method for preventing apricot trees from freezing. Background Technology

[0002] As one of my country's important economic fruit trees, the apricot tree is extremely sensitive to temperature during its flowering period, making it susceptible to natural low-temperature disasters such as late spring frosts and cold waves. These disasters can damage flower organs and significantly reduce fruit set, severely hindering the stable development of the apricot industry. Statistics show that in northern my country's apricot-producing areas, annual yield losses due to low-temperature freezing damage during the flowering period can reach 20%-50%, with some extreme years even resulting in total crop failure, causing huge economic losses to fruit farmers.

[0003] Traditional frost protection measures during the apricot blossom season mainly rely on two categories: physical protection (such as heating, fumigation, and covering) and the application of chemical antifreeze agents (CN114044716A). Physical protection measures are greatly limited by terrain and scale, and are difficult and costly to implement in large-scale apricot or mountain forests, with unstable protective effects. Chemical antifreeze agents (such as commercially available products like Shangfeng, Wolifeng, and Wobadun, whose technical basis can be found in patent CN114044716A, "An Antifreeze Agent for Apricot Blossoms and Fruits, Preparation and Method for Antifreeze of Apricot Blossoms and Fruits") improve the frost resistance of flower organs through mechanisms such as lowering the freezing point of cell sap and thickening cell walls, but they have significant limitations in practical applications. 1) Insufficient low-temperature protection: In extreme low-temperature environments ranging from -6℃ to -4℃, the effectiveness of traditional antifreeze agents is significantly reduced. When traditional antifreeze agents are used alone on flowering branches, the mortality rate of ovules and pistils is as high as 30%-67% (e.g., in the 3-3N experimental group using a certain conventional antifreeze agent, the mortality rate reached 36.67%). Even on non-flowering branches with relatively strong frost resistance, the mortality rate of ovules and pistils is still as high as 18.00% after using traditional antifreeze agents alone (e.g., in the 4-4N experimental group). In addition, these agents are easily washed away in rainy weather and have difficulty adhering effectively to the surface of branches, resulting in unstable antifreeze effects and failing to meet actual production needs.

[0004] 2) Failure to consider physiological differences in branches: During the apricot flowering period, there is a fundamental difference in the physiological state between flowering and non-flowering branches—flowering branches have fully expanded flower organs, high cell membrane permeability, and weak stress resistance; non-flowering branches are in the bud stage, with relatively intact cell structure and incomplete release of frost resistance potential. Existing technologies do not design differentiated treatment schemes for this difference, uniformly applying the same type of antifreeze, resulting in insufficient protection for flowering branches, excessive protection for non-flowering branches, or uneven effects, leading to low overall frost protection efficiency.

[0005] 3) Inability to address the root cause of damage: The core of low-temperature damage to apricot flower organs lies in cell membrane lipid peroxidation (increased malondialdehyde (MDA) content) and intracellular ice crystal formation. Traditional antifreeze agents can only enhance freeze resistance through external physical means; they cannot inhibit cell membrane lipid peroxidation or prevent intracellular ice crystal formation, leading to irreversible damage to flower organs even after freezing. It is noteworthy that Shanxi Agricultural University, in its patent CN114868745B, used a CaCl2-salicylic acid-ethylene glycol composite antifreeze agent to treat apricot flowers, demonstrating that regulating the antioxidant enzyme system (SOD, POD, etc.) through exogenous substances can effectively reduce membrane lipid peroxidation damage. This provides a theoretical basis for this invention to overcome the limitations of traditional antifreeze agents from a physiological mechanism perspective.

[0006] To overcome the aforementioned technical bottlenecks, there is an urgent need in this field to develop a frost protection technology that can improve frost resistance from the physiological mechanism level by addressing differences in flowering status, and can still maintain efficient protection under extreme low temperatures. Summary of the Invention

[0007] The purpose of this invention is to provide a graphene composite antifreeze that significantly enhances the permeability of traditional antifreeze by adding an appropriate concentration of graphene solution, promotes the uniform distribution of antifreeze in flower organ cells, and at the same time enhances the activity of superoxide dismutase (SOD), effectively removes reactive oxygen species induced by low temperature, and inhibits cell membrane lipid peroxidation.

[0008] A graphene composite antifreeze is derived by combining a traditional antifreeze with 3-7 mg / L graphene. In an optimized formulation, a traditional antifreeze is combined with 5 mg / L graphene.

[0009] According to the above scheme, the traditional antifreeze is prepared from commercially available antifreeze concentrate at the maximum dilution ratio.

[0010] According to the above scheme, the commercially available antifreeze stock solution includes any one of the following: Guoshangfeng, Wolifeng, Wobadun, Getaili, Qiangli, Bangsaike, Quanwang, North American Agricultural University, Shenneng, Zhixiaobai, Zuoba, Jiubaida, Zhonghui, and Linaka.

[0011] According to the above scheme, the thickness of the graphene sheet is 1-3 nm, and the lateral dimension is 50-200 nm.

[0012] Another objective of this invention is to provide a frost protection method based on the differences in flowering status of apricot trees, which utilizes the above-mentioned graphene composite antifreeze agent to perform different frost protection treatments on the physiological differences between flowering branches and non-flowering branches.

[0013] The frost protection method based on the differences in the flowering status of apricot trees includes the following steps: For non-flowering branches of apricot trees in the bud stage, apply the graphene composite antifreeze to the branches at a dosage of 30-100 ml / branch. For flowering branches of apricot trees during their peak blooming period, apply the graphene composite antifreeze to the branches at a dosage of 30-100 ml per branch.

[0014] According to the above scheme, none of the flowers on the non-flowering branches have opened. 40-60% of the flowers on the flowering branches have opened.

[0015] In the optimized scheme, the dosage of the graphene composite antifreeze is 40-60 ml / unit. The optimal dosage of the graphene composite antifreeze is 50 ml / unit.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: (i) Significantly reduces the mortality rate of ovules in the style and improves the frost resistance efficiency.

[0017] Outstanding protection against extreme low temperatures: The mortality rate of ovules in the style of the unflowering branches treated with this invention is ≤5.33% at extreme low temperatures of -8℃ to -5℃, while the mortality rate of the control group treated with traditional single antifreeze is 18%, a reduction of more than 70%; even at moderate low temperatures of -5℃ to -2℃, the mortality rate of this batch can still be stably controlled within 8%, far below the industry average.

[0018] Significant protective effect on flowering branches: The mortality rate of ovules in the style of flowering branches treated with this invention was reduced from 36.67% to 22.67% at low temperatures of -4℃ to -2℃, a reduction of 38.2%, effectively solving the problem of weak frost resistance of flowering branches.

[0019] Full-flowering-period protection coverage: This invention achieves full-stage protection from the bud stage to the full bloom stage, protecting both flowering and non-flowering branches and avoiding protection gaps caused by physiological differences in branches. The overall frost protection success rate is increased to over 90%.

[0020] (ii) Optimize physiological mechanisms and enhance the antifreeze properties of flower organs.

[0021] Inhibiting cell membrane lipid peroxidation: The addition of graphene can significantly enhance the activity of SOD enzyme in apricot flower organs, accelerate the removal of reactive oxygen species (such as superoxide anions and hydrogen peroxide) induced by low temperature, reduce malondialdehyde (MDA) content, reduce cell membrane damage, and enhance the antifreeze ability of flower organs from the physiological mechanism level, rather than relying solely on external physical protection.

[0022] Improved antifreeze utilization efficiency: The high permeability of graphene can promote the uniform distribution of antifreeze active ingredients in flower organ cells, avoiding the problem that traditional antifreeze only forms a film on the surface and cannot penetrate into the cells, thus increasing the effective utilization rate of antifreeze by more than 15% (reduced dosage), thereby improving the protective effect while reducing the amount of antifreeze used.

[0023] (iii) The cost is controllable, the applicability is strong, and it is easy to promote.

[0024] Reduced antifreeze usage: Taking WoliFong antifreeze as an example, traditional single-treatment requires an average of about 0.1015 ml of antifreeze concentrate per branch, while the technology of this invention requires only 0.0625 ml of concentrate per branch, reducing antifreeze usage by more than 38%, significantly reducing chemical costs and environmental pressure.

[0025] Graphene is low in cost: the cost of graphene concentrate required for a single branch treatment is less than 0.03 yuan. Even with the cost of antifreeze, the cost of frost protection for a single apricot tree throughout its flowering period is only about 0.5 yuan, which is far lower than physical protection (such as building windbreaks, which cost about 5 yuan per tree) and traditional antifreeze treatment (which costs about 1.2 yuan per tree), making it highly economically feasible.

[0026] Adaptable to different planting scenarios: The technology of this invention does not require complicated equipment and can be applied with just a conventional sprayer. It is easy to operate and can be precisely applied in small-scale experimental areas such as the Xinglin Garden of Datong University South Campus in Shanxi Province, and promoted on a large scale in mountain forest farms such as Zhoushizhuang Great Wall Mountain Forest Farm. It is also highly adaptable to environmental conditions such as soil and climate, and is suitable for application in most apricot producing areas in northern my country. Detailed Implementation

[0027] The following embodiments further illustrate the technical solution of the present invention, but are not intended to limit the scope of protection of the present invention. The materials and equipment used in the embodiments are all commercially available conventional products, and unless otherwise stated, the experimental methods are all conventional methods.

[0028] A specific embodiment provides a graphene concentrate: the graphene concentrate is prepared using the method described in patent CN106587018A, specifically: using high-purity graphite as electrodes, at a pulse frequency of 40-60 Hz, a voltage of 12-20V, and a current density of 50-100 A / m. 2 Electrolysis for 150-200 hours at a temperature between 10℃ and 60℃ using sodium sulfate or potassium sulfate solution (concentration 0.04%-0.09%) yields a graphene aggregate sol with a solid content of 0.3%-0.7%. After spray drying (90-150℃), the sol is reconstituted to prepare a concentrated solution with a solid content of 3‰. The graphene sheets in this concentrated solution have a thickness of 1-3 nm and a lateral dimension of 50-200 nm, exhibiting good dispersibility and suitability for compound applications in agricultural antifreeze. At this concentration, the graphene exhibits good dispersibility and can accurately achieve the target working solution concentration after compounding, avoiding the impact of graphene agglomeration on the antifreeze effect.

[0029] In the specific implementation method, the preparation process of the composite antifreeze requires strict control of dosage calculation and mixing conditions to ensure uniform dispersion and accurate concentration of each component. The specific steps are as follows: 1. Dosage Calculation (taking the preparation of 50ml working solution as an example). 1) Antifreeze stock solution dosage calculation: Antifreeze stock solution volume = Total volume of target working solution ÷ Maximum dilution factor of antifreeze. For example, when using Wolifeng antifreeze with a maximum dilution factor of 800, the required stock solution volume = 50ml / 800 = 0.0625ml; when using Guoshangfeng antifreeze with a maximum dilution factor of 100, the required stock solution volume = 50ml / 100 = 0.5ml.

[0030] 2) Calculation of graphene concentrate usage: Graphene concentrate mass = (Graphene concentration in target working solution × Total volume of target working solution) / Solid content of graphene concentrate. Given a target concentration of 5 mg / L, a total volume of 50 ml (i.e., 0.05 L), and a solid content of 3‰ (0.003), the calculated graphene concentrate mass = (5 mg / L × 0.05 L) / 0.003 ≈ 83.33 mg.

[0031] 2. Mixing and Volume Adjustment. Take a clean glass or plastic container, first add the calculated amount of antifreeze stock solution, then add the precisely weighed graphene concentrate, and gently shake the container to initially mix the two. Slowly add deionized water to the container while stirring, until the solution volume is close to 50 ml. After standing for 5 minutes, add deionized water to bring the volume to 50 ml, ensuring the working solution volume is accurate.

[0032] 3. Homogenization Treatment. Place the prepared mixture in a magnetic stirrer or high-speed shear mixer and stir at 2000 rpm for 10 minutes to ensure uniform dispersion of graphene in the solution, preventing agglomeration and forming a stable composite antifreeze working solution. After stirring, it must be used within 2 hours. If not used immediately, it must be sealed and stored away from light, and the storage time should not exceed 24 hours. Before use, it must be stirred again at 1500 rpm for 5 minutes.

[0033] The specific implementation method was tested at the Apricot Grove Garden on the South Campus of Datong University, Shanxi Province. The area covered was half a mu (approximately 333.33 square meters). The apricot tree variety used was the locally cultivated "Golden Sun" apricot, with trees aged 5-8 years and exhibiting robust growth. Approximately 20 trees were used, with a spacing of 3m x 5m. Environmental characteristics: Located on campus, the area enjoys ample sunlight, good ventilation, sandy loam soil with moderate fertility, and convenient irrigation, making it suitable as an experimental site for accurate data recording and observation.

[0034] Example 1 Preparation of Wolifeng compound antifreeze agent in Xinglin Garden, South Campus of Datong University, Shanxi Province, and its application treatment on non-flowering branches.

[0035] (I) Preparation of experimental materials 1) Antifreeze: Wolifeng antifreeze (commercially available, the product manual indicates a maximum dilution ratio of 800 times, the content of active ingredients is ≥40%, and it meets the industry standard for agricultural antifreeze).

[0036] 2) Graphene concentrate: According to patent CN201611158642.X, a graphene concentrate with a solid content of 3‰ (commercially available, purity ≥99%, graphene sheet thickness 1-3nm, lateral size 50-200nm, good dispersibility, and no obvious agglomeration).

[0037] 3) Equipment: Electronic analytical balance (accuracy 0.01mg, model FA2004), pipette (range 0.1-1ml, accuracy 0.001ml), 50ml volumetric flask (glass material, meeting Class A accuracy standard), magnetic stirrer (adjustable speed range 0-5000 rpm, model 85-2), backpack electric sprayer (volume 10L, atomized particle size 50-100μm, adjustable nozzle angle).

[0038] 4) Experimental subjects: Unflowering branches of the "Golden Sun" apricot tree in the apricot orchard behind the Aoyu Restaurant on the South Campus of Datong University in Shanxi Province. Ten branches with healthy growth, no pests or diseases, and a uniform number of flower buds (about 20-30 flower buds per branch) were selected and marked. Each branch was a replicate and numbered from 4-4GN-1 to 4-4GN-10. At the same time, five adjacent unflowering branches were selected as the control group (only a single Wolifeng antifreeze was applied and numbered from 4-4N-1 to 4-4N-5).

[0039] (II) Preparation of composite antifreeze (taking 500ml working solution as an example) 1) Dosage calculation: According to the compounding rules, the maximum dilution ratio of Worifon antifreeze is 800 times. Therefore, the volume of the original antifreeze solution = 500ml / 800 = 0.625ml; the mass of graphene concentrate = (5mg / L×0.5L) / 0.003≈833.33mg.

[0040] 2) Mixing operation: Take a clean 500ml beaker, first use a pipette to accurately transfer 0.625ml of WoliFong antifreeze stock solution into the beaker, then use an electronic analytical balance to accurately weigh 833.33mg of graphene concentrate and add it into the beaker, and gently stir with a glass rod for 1 minute to make the two initially mixed.

[0041] 3) Volume Adjustment and Homogenization: Slowly add deionized water to the beaker while stirring until the solution volume is close to 500 ml. Transfer the solution to a 500 ml volumetric flask. Rinse the beaker 2-3 times with a small amount of deionized water, pouring all the rinsing solution into the volumetric flask. Finally, adjust the volume to the 500 ml mark with deionized water. Pour the solution from the volumetric flask into the stirring tank of a magnetic stirrer, set the speed to 2000 rpm, and stir for 10 minutes. Observe the solution state every 2 minutes during this period to ensure that the graphene does not agglomerate. After stirring, a uniform and transparent Wolifeng composite antifreeze working solution is obtained.

[0042] (iii) Field application 1) Application time: Choose a sunny and windless morning between 9:00 and 11:00, when the temperature rises to 5-8℃, there is no dew on the surface of the flower buds, and according to the weather forecast, the temperature will drop to -5℃ to -3℃ in the next 24 hours.

[0043] 2) Application method: Pour the prepared compound antifreeze working solution into a backpack electric sprayer, adjust the nozzle angle to 45°, and keep the nozzle about 30cm away from the branch surface. Spray evenly onto the marked 10 non-flowering branches, ensuring that each flower bud is covered with a thin layer of solution, ideally without dripping. The amount applied per branch is strictly controlled at 50ml (the spraying time per branch is calculated to be approximately 15 seconds by pre-calibrating the sprayer flow rate). The control group branches are treated with the same amount of single WoliFong antifreeze working solution (diluted 800 times), using the same application method as the treatment group.

[0044] (iv) Effect monitoring and data recording Observation after low temperature: After the low temperature process ends (about 48 hours later), observe the growth status of the flower buds on each branch and record the color change of the petals and the wilting of the flower buds.

[0045] Results of observation after low temperature (petal discoloration and bud wilting): 1) Treatment group (4-4GN, treated with Wolifeng + 5mg / L graphene composite antifreeze) Petal discoloration: The vast majority of flower buds have normal petal color, which is light pink or white. Only about 6% of the flower buds have slight water stains or very slight brown spots on the edges of the petals.

[0046] Flower bud wilting: The flower buds are plump and firm, with no obvious signs of wilting due to water loss. Only about 5% of the flower buds showed slight wrinkling, but still maintained their basic structural integrity and had the potential to continue developing.

[0047] Overall condition: The vast majority of flower buds are growing well, and there are no obvious visual signs of frost damage, which is highly consistent with the extremely low mortality rate of style ovules (5.33%).

[0048] 2) Control group (4-4N, treated with only WoliFon antifreeze) Petal discoloration: Significant frost damage symptoms were observed. Over 25% of the flower buds and petals showed marked browning, some appearing water-soaked and translucent, especially at the base and midrib of the petals. Approximately 15% of the flower buds and petals turned completely dark brown.

[0049] Flower bud wilting: Wilting is widespread. Approximately 20% of the flower buds are visibly dehydrated, dry, and shriveled, feeling soft to the touch and lacking elasticity. Some flower buds (approximately 5%) have already fallen off from the receptacle.

[0050] Overall condition: Widespread frost damage is visible to the naked eye, and the vitality of flower buds is severely reduced, corresponding to a high mortality rate of style ovules (18.00%).

[0051] Conclusion: Observational results show that the treatment group treated with the graphene composite antifreeze provided by this invention exhibited a significantly lower proportion of petal discoloration and wilting after exposure to temperatures ranging from -5°C to -3°C compared to the control group treated with a traditional single antifreeze agent. This demonstrates, both physiologically (style and ovule mortality rate) and phenotypically, the remarkable effectiveness of this invention in alleviating visual symptoms of low-temperature freezing damage to apricot flower organs and protecting the morphological integrity of flower buds.

[0052] Determination of stylopodium mortality rate: Ten flower buds were randomly selected from each branch. The petals were carefully peeled open with a dissecting needle, and the style and ovules were removed. They were observed under an optical microscope (magnification 10×20) to determine whether the style and ovules were dead (death criteria: style turns brown, ovules lose their luster and turn brown). The number of dead flowers was counted, and the mortality rate was calculated (mortality rate = number of dead style and ovules ÷ total number of observed flowers × 100%).

[0053] Results: In the 4-4GN group (10 non-flowering branches after application of the compound antifreeze), the average mortality rate of style and ovules was 5.33%, with the lowest mortality rate at 4.00% (4-4GN-3 branch) and the highest at 6.67% (4-4GN-8 branch). In the control group (4-4N group), the average mortality rate of style and ovules in the 5 non-flowering branches was 18.00%, with the lowest at 16.00% and the highest at 20.00%. The data indicate that the Wolifeng compound antifreeze significantly reduces the mortality rate of style and ovules in non-flowering branches, showing better results than traditional single antifreeze agents.

[0054] Example 2 Preparation of compound antifreeze agent for fruit trees in Xinglinyuan, South Campus of Datong University, Shanxi Province, and its application treatment on flowering branches.

[0055] (I) Preparation of experimental materials 1) Antifreeze: Guoshangfeng antifreeze (maximum dilution ratio 100 times).

[0056] 2) Graphene concentrate: Same as in Example 1, with a solid content of 3‰.

[0057] 3) Equipment: Electronic analytical balance, pipette, magnetic stirrer, sprayer, etc.

[0058] 4) Experimental subjects: Select a batch of flowering branches, numbered from 3-3GN-1 to 3-3GN-10. At the same time, select 5 adjacent flowering branches as the control group (only a single fruit-on-the-fruit antifreeze agent was applied, numbered from 3-3N-1 to 3-3N-5).

[0059] (II) Preparation of compound antifreeze (taking 500ml as an example) 1) Dosage calculation: According to the compounding rules, the maximum dilution ratio of Guoshangfeng antifreeze is 100 times. Therefore, the volume of Guoshangfeng antifreeze stock solution = 500ml / 100 = 5.0ml; the mass of graphene concentrate = (5mg / L×0.5L) / 0.003≈833.33mg.

[0060] 2) Mixing and homogenization: First add the antifreeze stock solution, then add the graphene concentrate, and after adjusting the volume, stir at 2000 rpm for 10 minutes to obtain a uniform composite working solution.

[0061] (iii) Field application 1) Application time: when the air temperature is 5–10℃ and there is no wind.

[0062] 2) Application method: Same as in Example 1, spray 50ml of compound antifreeze on each branch.

[0063] (iv) Effect monitoring and data recording Mortality determination of ovules in style: After exposure to low temperatures of -4℃ to -2℃, the mortality rate was statistically analyzed by dissection.

[0064] Results: The average mortality rate after application of compound antifreeze (3-3GN group) was 22.67%, while the average mortality rate in the control group (3-3N group) was 36.67%.

[0065] Conclusion: Applying a compound antifreeze agent of Guoshangfeng + 5 mg / L graphene to flowering branches significantly enhanced the permeability of the antifreeze agent and the activity of SOD enzyme, effectively inhibited cell membrane lipid peroxidation, and reduced the mortality rate of flowering branches under moderate low temperature by 40.7%, demonstrating a significant protective effect.

[0066] The technology of this invention can significantly improve the fruit setting rate and yield per tree of apricot trees, and reduce the rate of deformed fruit. Moreover, the technical advantages are still obvious in forest farms with relatively complex environmental conditions, indicating that the technology of this invention has wide applicability and stability.

Claims

1. A graphene composite deicing agent, characterized by It is made by combining traditional antifreeze with 3-7 mg / L of graphene.

2. The graphene composite antifreeze agent as described in claim 1, characterized in that... It is made by combining traditional antifreeze with 5 mg / L graphene.

3. The graphene composite antifreeze agent as described in claim 1, characterized in that... The traditional antifreeze is formulated from commercially available antifreeze concentrate at the maximum dilution ratio.

4. The graphene composite antifreeze agent as described in claim 3, characterized in that... The commercially available antifreeze concentrate includes any one of the following manufacturers: Guoshangfeng, Wolifeng, Wobadun, Getaili, Qiangli, Bangsaike, Quanwang, North American Agricultural University, Shenneng, Zhixiaobai, Zoba, Jiubaida, Zhonghui, and Linaka.

5. The graphene composite antifreeze agent as described in claim 1, characterized in that... The graphene sheets have a thickness of 1-3 nm and a lateral dimension of 50-200 nm.

6. A frost protection method based on differences in apricot tree flowering status, characterized in that... Includes the following steps: For non-flowering branches of apricot trees in the bud stage, apply the graphene composite antifreeze agent as described in any one of claims 1-5 to the branches at a dosage of 30-100 ml / branch; For flowering branches of apricot trees during their peak flowering period, apply the graphene composite antifreeze agent as described in any one of claims 1-5 to the branches at a dosage of 30-100 ml / branch.

7. The frost protection method based on the differences in flowering status of apricot trees as described in claim 6, characterized in that... The flowers on the unopened branches were all unopened.

8. The frost protection method based on the differences in flowering status of apricot trees as described in claim 6, characterized in that... The flowering branches have 40-60% of their flowers open.

9. The frost protection method based on the differences in flowering status of apricot trees as described in claim 6, characterized in that... The amount of the graphene composite antifreeze is 40-60 ml / unit.

10. The frost protection method based on the differences in flowering status of apricot trees as described in claim 6, characterized in that... The amount of the graphene composite antifreeze is 50 ml / unit.