Application of oligomeric hyaluronic acid in improving cold resistance of crops

Abstract

The invention discloses application of oligomeric hyaluronic acid in improving cold resistance of crops, and belongs to the technical field of application of oligomeric hyaluronic acid. The application comprises the following steps: (1) diluting oligomeric hyaluronic acid to obtain an oligomeric hyaluronic acid diluent; and (2) spraying the oligomeric hyaluronic acid diluent to crops. According to the method, the oligomeric hyaluronic acid diluent is used for spraying the leaf surfaces of the crops before cooling, the cold resistance of the crops can be remarkably improved, the growth of the crops is protected, the yield of the crops is increased, and the method is convenient to operate, economical, efficient, low in application amount, low in cost and beneficial to reducing the economic cost.

Description

Technical Field

[0001] The invention relates to application of oligomeric hyaluronic acid in improving the cold resistance of crops, and belongs to the technical field of application of oligomeric hyaluronic acid. Background Art

[0002] Hyaluronic acid (HA), also known as hyaluronic acid, is an acidic mucopolysaccharide. It is an unbranched high-molecular glycosaminoglycan composed of repeating units of N-acetylglucosamine and D-glucuronic acid disaccharides. It exists in the interstitial cells of animal tissues and the capsules of certain bacteria. In plant immunity, carbohydrates mainly act as model molecules to activate the host's innate immune system response, and the PTI response plays an important role in the host's extracellular immunity. In this process, oligosaccharides play an important role as model molecules. Oligomeric hyaluronic acid refers to hyaluronic acid with a molecular weight of less than 10kDa. Studies have shown that molecular weight has a great influence on the activity of hyaluronic acid, and hyaluronic acid of different molecular weights even exhibits completely opposite activities.

[0003] Cold waves can cause a sudden drop in temperature, which may cause low-temperature damage, including frostbite and freezing damage. In cold waves, the growth rate of crops will slow down or stagnate, affecting their normal development and yield. In severe cases, the water in the tissues of crops may freeze, causing cell rupture and tissue damage, which will cause frostbite on the leaves and stems of crops, and even lead to plant death.

[0004] Therefore, it is crucial to minimize the impact of cold waves on crops and protect crop growth and yield. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide an application of oligomeric hyaluronic acid in improving the cold resistance of crops, effectively improving the cold resistance of crops, protecting the growth of crops, and increasing crop yields.

[0006] In order to solve the above technical problems, the technical solutions provided by the present invention are as follows: An application of oligomeric hyaluronic acid in improving the cold resistance of crops comprises the following steps: (1) diluting the oligomeric hyaluronic acid to obtain an oligomeric hyaluronic acid diluted solution; (2) Spray crops with diluted oligomeric hyaluronic acid solution.

[0007] Furthermore, in step (1), the content of the oligomeric hyaluronic acid is 0.5-99.9%.

[0008] Furthermore, in step (1), the concentration of the oligomeric hyaluronic acid dilution solution is 200-2000 ppm.

[0009] Furthermore, in step (2), 1-3 days before the temperature drops suddenly, the crops are sprayed with the diluted oligomeric hyaluronic acid solution.

[0010] Furthermore, in step (2), the oligomeric hyaluronic acid dilution solution is sprayed on the leaves.

[0011] Furthermore, in step (2), the spraying method is: spraying once a day, and spraying continuously for 1-3 days.

[0012] Furthermore, in step (2), the spraying amount is: the total amount of the oligomeric hyaluronic acid dilution sprayed per acre of crops is 15-60L.

[0013] Furthermore, in step (2), the specific operation of spraying is: one day before the temperature drops suddenly, the crops are sprayed once a day, and 30L of oligomeric hyaluronic acid dilution solution is sprayed on each acre of leaves each time, and the spraying is continued for three days.

[0014] Furthermore, in step (2), the foliar spraying time is: before 10 am or after 4 pm. Spraying during this time period can avoid high temperature and strong sunlight from affecting the effect of oligomeric hyaluronic acid.

[0015] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention uses a diluted oligomeric hyaluronic acid solution to spray the crop leaves before cooling, which can significantly improve the cold resistance of the crops, protect the growth of the crops, and increase the crop yield.

[0016] (2) The oligomeric hyaluronic acid used in the present invention is a natural ingredient and has no side effects when sprayed on crops. It also has no effect on the health of humans and animals and is safe, harmless and environmentally friendly.

[0017] (3) The present invention uses the diluted oligomeric hyaluronic acid solution for foliar spraying, which is easy to operate, economical and efficient, and has a low application amount and low cost, which is conducive to reducing economic costs. DETAILED DESCRIPTION

[0018] Example 1 An application of oligomeric hyaluronic acid in improving the cold resistance of crops comprises the following steps: (1) diluting an oligomeric hyaluronic acid having a content of 99.9% to obtain an oligomeric hyaluronic acid dilution solution having a concentration of 2000 ppm; (2) One day before the temperature drops, spray the crops with diluted oligomeric hyaluronic acid solution once before 10 am every day. Spray 30L of diluted oligomeric hyaluronic acid solution on the leaves of each acre of crops each time, and spray continuously for 1 day.

[0019] Example 2 An application of oligomeric hyaluronic acid in improving the cold resistance of crops comprises the following steps: (1) diluting 0.5% oligomeric hyaluronic acid to obtain a 200 ppm oligomeric hyaluronic acid dilution solution; (2) Three days before the temperature drops, spray the crops with diluted oligomeric hyaluronic acid solution once after 4 pm every day. Spray 60L of diluted oligomeric hyaluronic acid solution on the leaves of each acre of crops each time, and spray continuously for 3 days.

[0020] Example 3 An application of oligomeric hyaluronic acid in improving the cold resistance of crops comprises the following steps: (1) diluting an oligomeric hyaluronic acid having a content of 50.0% to obtain an oligomeric hyaluronic acid dilution solution having a concentration of 1000 ppm; (2) One day before the temperature drops, spray the crops with diluted oligomeric hyaluronic acid solution once before 10 am every day. Spray 15L of diluted oligomeric hyaluronic acid solution on the leaves of each acre of crops each time, and spray continuously for 1 day.

[0021] Example 4 An application of oligomeric hyaluronic acid in improving the cold resistance of crops comprises the following steps: (1) diluting the oligomeric hyaluronic acid having a content of 90.0% to obtain an oligomeric hyaluronic acid dilution solution having a concentration of 1500 ppm; (2) Two days before the temperature drops, spray the crops with diluted oligomeric hyaluronic acid solution once after 4 pm every day. Spray 20L of diluted oligomeric hyaluronic acid solution on the leaves of each acre of crops each time, and spray continuously for 2 days.

[0022] Experimental Example 1 Test materials: Tobacco "Zhongyan 98", grown for 8 weeks, with relatively consistent growth status.

[0023] Experimental steps: Oligomeric hyaluronic acid dilutions with concentrations of 200 ppm, 500 ppm, 1000 ppm, 1500 ppm, 2000 ppm, and 5000 ppm, brown algae oligosaccharides with a concentration of 1000 ppm, hyaluronic acid solution with a concentration of 1000 ppm, and clean water were sprayed evenly on both sides of the tobacco leaves, and each leaf was sprayed with 5 mL, and placed in a constant temperature and light incubator (4±1)℃ for low temperature stress culture. The blank control was untreated tobacco plants at room temperature (25℃). The light exposure time was 12h / d. The changes in soluble sugar, free proline, and malondialdehyde in tobacco leaves were detected at 12h, 24h, and 36h of low temperature stress, respectively. The results are shown in Table 1.

[0024] Table 1. Effects of different treatments on the contents of soluble sugar, free proline and malondialdehyde in tobacco leaves In plants, soluble sugar and free proline can alleviate the osmotic stress caused by low temperature damage to plants, and the malondialdehyde content is an important indicator of the degree of damage to plant cell membranes. Therefore, detecting the content of soluble sugar, free proline and malondialdehyde in plants can, to a certain extent, determine the degree of damage to plants caused by adverse stress.

[0025] As shown in Table 1, after low temperature stress, the contents of soluble sugar, free proline and malondialdehyde in the tobacco leaf surface of the water treatment group increased dramatically with the extension of time. When the oligomeric hyaluronic acid diluent with a concentration of 200-2000ppm was sprayed, the contents of soluble sugar, free proline and malondialdehyde in the tobacco leaf surface decreased. Among them, after spraying the oligomeric hyaluronic acid diluent with a concentration of 1500 ppm, the contents of soluble sugar, free proline and malondialdehyde in the tobacco leaf surface were significantly reduced, and the reduction was significantly greater than that of the treatment of spraying brown algae oligosaccharides and hyaluronic acid solution. However, when the concentration of the oligomeric hyaluronic acid diluent reached 5000ppm, the contents of soluble sugar, free proline and malondialdehyde in the tobacco leaf surface increased sharply, indicating that a higher concentration of oligomeric hyaluronic acid diluent would aggravate the damage of tobacco under low temperature. It can be seen that by spraying the oligomeric hyaluronic acid dilution with a concentration of 200-2000 ppm, the contents of soluble sugar, free proline and malondialdehyde in the tobacco leaf surface can be significantly reduced, and the cold resistance of tobacco can be improved.

[0026] Experimental Example 2 Test material: Longjiao No. 6, 7-10 true leaves, consistent growth status.

[0027] Experimental steps: Spray the diluted oligomeric hyaluronic acid with concentrations of 200 ppm, 500 ppm, 1000 ppm, 1500 ppm, 2000 ppm, 5000 ppm, brown algae oligosaccharide with a concentration of 1000 ppm, hyaluronic acid solution with a concentration of 1000 ppm, and clean water evenly onto the pepper leaves. After continuous spraying for 3 days, the pepper seedlings were placed in a 15℃ / 10℃ (day / night) incubator with a light duration of 12h / d. The blank control was a pepper plant without treatment at room temperature (25℃). The changes in the content of soluble sugar, free proline, and malondialdehyde in pepper leaves were detected at 12h, 24h, and 36h of low temperature stress, respectively. The results are shown in Table 2.

[0028] Table 2. Effects of different treatments on the contents of soluble sugar, free proline and malondialdehyde in pepper leaves As shown in Table 2, after low temperature stress, the contents of soluble sugar, free proline and malondialdehyde in the pepper leaves of the water treatment group increased dramatically with the extension of time. When the oligomeric hyaluronic acid dilution with a concentration of 200-2000ppm was sprayed, the contents of soluble sugar, free proline and malondialdehyde in the pepper leaves decreased. Among them, after spraying the oligomeric hyaluronic acid dilution with a concentration of 1000 ppm, the contents of soluble sugar, free proline and malondialdehyde in the pepper leaves decreased significantly, and the reduction was significantly greater than the treatment of spraying brown algae oligosaccharides and hyaluronic acid solution. However, when the concentration of the oligomeric hyaluronic acid dilution reached 5000ppm, the contents of soluble sugar, free proline and malondialdehyde in the pepper leaves increased sharply, indicating that a higher concentration of oligomeric hyaluronic acid dilution would aggravate the damage to the pepper leaves at low temperatures. It can be seen that by spraying the oligomeric hyaluronic acid dilution with a concentration of 200-2000ppm, the contents of soluble sugar, free proline and malondialdehyde in the leaves of pepper can be significantly reduced, and the cold resistance of pepper can be improved.

[0029] The testing method in the specific implementation manner of the present invention is as follows: 1. Determination of soluble sugar content The method for determining soluble sugar was based on the method of Angela et al. (1993).

[0030] 2. Determination of free proline content The free proline content was determined according to the ninhydrin method of Li Shaojun et al. (2005).

[0031] 3. Determination of malondialdehyde content The malondialdehyde content was determined by referring to the 2-thiobarbituric acid colorimetric method of Gao Junfeng (2006).

Claims

1. An application of oligomeric hyaluronic acid in improving the cold resistance of crops, characterized in that: The steps include: (1) diluting the oligomeric hyaluronic acid to obtain an oligomeric hyaluronic acid diluted solution; (2) Spray crops with diluted oligomeric hyaluronic acid solution.

2. The use of oligomeric hyaluronic acid according to claim 1 in improving the cold resistance of crops, characterized in that: In step (1), the content of the oligomeric hyaluronic acid is 0.5-99.9%.

3. The use of oligomeric hyaluronic acid according to claim 1 in improving the cold resistance of crops, characterized in that: In step (1), the concentration of the oligomeric hyaluronic acid dilution solution is 200-2000 ppm.

4. The use of the oligomeric hyaluronic acid according to any one of claims 1 to 3 for improving the cold resistance of crops, characterized in that: Step (2), spraying crops with diluted oligomeric hyaluronic acid solution 1-3 days before the temperature drops suddenly.

5. The use of oligomeric hyaluronic acid according to claim 4 for improving the cold resistance of crops, characterized in that: In step (2), the oligomeric hyaluronic acid dilution solution is sprayed on the leaves.

6. The use of oligomeric hyaluronic acid according to claim 1 for improving the cold resistance of crops, characterized in that: In step (2), the spraying cycle is: spraying once a day, and spraying continuously for 1-3 days.

7. The use of oligomeric hyaluronic acid according to claim 6 for improving the cold resistance of crops, characterized in that: In step (2), the spraying amount is: the total amount of the oligomeric hyaluronic acid dilution sprayed per acre of crops is 15-60L.

8. The use of oligomeric hyaluronic acid according to claim 1 for improving the cold resistance of crops, characterized in that: In step (2), the specific operation of spraying is: one day before the temperature drops suddenly, the crops are sprayed once a day, and 30L of oligomeric hyaluronic acid dilution solution is sprayed on each acre of leaves each time, and the spraying is continued for three days.

9. The use of the oligomeric hyaluronic acid according to claim 7 or 8 for improving the cold resistance of crops, characterized in that: In step (2), the foliar spraying time is: before 10 am or after 4 pm.

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