Nutrient solution for hydroponic vegetable and preparation method therefor

Abstract

The present invention relates to the technical field of soilless cultivation, and provides a nutrient solution for a hydroponic vegetable and a preparation method therefor. The nutrient solution for the hydroponic vegetable comprises the following components: calcium nitrate tetrahydrate, ammonium nitrate, potassium nitrate, urea, sodium iron ethylenediaminetetraacetate, ammonium dihydrogen phosphate, magnesium sulfate heptahydrate, sodium molybdate, a bacteriostatic agent, and water. By adding a special bacteriostatic agent to a hydroponic nutrient solution, the present invention can prevent water quality deterioration caused by the propagation of microorganisms, enhance seedling vigor, promote nutrient accumulation, prevent and control diseases and insect pests, and significantly improves the nutritional quality and flavor during vegetable hydroponics, realizing healthy hydroponic production of vegetables. In addition, by further improving the bacteriostatic agent, the bacteriostatic agent can be gradually released in the nutrient solution, realizing sustained bacteriostasis for the nutrient solution and further stabilizing the water quality of the nutrient solution.

Description

A nutrient solution for hydroponic vegetables and its preparation method Technical Field

[0001] This invention relates to the field of soilless cultivation technology, specifically to a nutrient solution for hydroponic vegetables and its preparation method. Background Technology

[0002] Vegetables have always been loved by people because of their variety, the availability of many essential vitamins and minerals, and their delicious taste. However, in order to eat off-season vegetables, people now use greenhouse cultivation. At the same time, in order to increase the yield of greenhouse vegetables, pesticides and various growth hormones are used, which greatly reduces the nutritional content of vegetables, makes them taste worse, and makes the soil more susceptible to the spread of pests and diseases, as well as the decline in soil fertility and compaction under continuous cultivation.

[0003] Hydroponics is a type of soilless cultivation in which crops are grown in a nutrient solution. As a new and environmentally friendly modern soilless plant cultivation technology, hydroponics can effectively solve the problems of crop cultivation being limited by land resources and natural conditions.

[0004] Hydroponics eliminates the hassle of cleaning associated with contact with soil and substrates, and its growth cycle is short and turnover is fast. Compared with soil-grown vegetables, hydroponically grown vegetables are cleaner, fresher, and of superior quality. Hydroponics uses nutrient solution as the cultivation medium, and the effectiveness of the vegetables in absorbing the nutrient solution determines the quality of plant growth. Hydroponic vegetables can only be maintained by liquid fertilizer. Chinese patent document CN112314420A discloses a hydroponic method for bok choy and its nutrient solution. However, in hydroponics, other aquatic plants tend to grow in the water, which consume a lot of nutrients. Furthermore, cleaning these aquatic organisms is tedious, requiring large-scale water changes to maintain basic cleanliness. Summary of the Invention

[0005] The main objective of this invention is to provide a nutrient solution for hydroponic vegetables, which solves the technical problem of needing to change water frequently over a large area in the above-mentioned background technology, so as to utilize and create economic value, reduce operating costs, and improve crop growth, yield and quality.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] A nutrient solution for hydroponic vegetables comprises the following components: calcium nitrate tetrahydrate, ammonium nitrate, potassium nitrate, urea, sodium iron ethylenediaminetetraacetate, ammonium dihydrogen phosphate, magnesium sulfate heptahydrate, sodium molybdate, antibacterial agent, and water.

[0008] Preferably, the nutrient solution for hydroponic vegetables comprises the following components by mass percentage: 0.1-10 wt% calcium nitrate tetrahydrate, 0.1-10 wt% ammonium nitrate, 0.1-10 wt% potassium nitrate, 0.1-5 wt% urea, 0.1-2 wt% sodium iron ethylenediaminetetraacetate, 0.1-10 wt% ammonium dihydrogen phosphate, 0.1-10 wt% magnesium sulfate heptahydrate, 0.1-5 wt% sodium molybdate, 0.01-1 wt% antibacterial agent, and the balance being water.

[0009] Preferably, the antibacterial agent is a mixture of ursolic acid, oleanolic acid, zinc sulfate, sodium bisulfite, and citrate fatty acid ester; the mass ratio of the five components is 1-3:2-4:0.1-1:0.1-0.5:0.1-0.5.

[0010] More preferably, the method for preparing the antibacterial agent includes the following steps:

[0011] S1. Dissolve ursolic acid, oleanolic acid, zinc sulfate, sodium bisulfite, and citrate fatty acid ester in water, and then disperse them by high-speed stirring to obtain an antibacterial agent solution;

[0012] S2. After crushing the straw, add it to the antibacterial agent solution, stir at room temperature, add sodium carboxymethyl cellulose and sesame gum, perform high-speed shear dispersion treatment, add sodium tripolyphosphate, heat to react, and centrifuge to collect the solids to obtain the antibacterial agent.

[0013] More preferably, the amount of straw used in step S2 is 20-30 wt% of the antibacterial agent solution.

[0014] More preferably, in step S2, the mass ratio of sodium carboxymethyl cellulose to sesame gum is 1-3:2-5.

[0015] More preferably, the sesame gum is carboxymethylated sesame gum, which is prepared by mixing and stirring sesame gum, sodium hydroxide aqueous solution, and ethanol; adding monochloroacetic acid and stirring to obtain a mixture; and heating the mixture to react and obtain carboxymethylated sesame gum.

[0016] More preferably, the high-speed shearing condition is a rotation speed of 2000-3000 rpm.

[0017] As the use time of hydroponic nutrient solution increases, the open cultivation environment makes it easy for microorganisms to multiply, leading to water quality deterioration, algal toxin production, and competition for nutrients with plants. Insufficient nutrients in the water can cause root rot in vegetables, affecting their growth. Existing technologies require frequent replacement of hydroponic nutrient solutions, which not only increases production costs but also wastes water resources. This invention, by adding a special antibacterial agent to the hydroponic nutrient solution, can prevent microbial growth that leads to water quality deterioration, promote strong seedlings, accelerate nutrient accumulation, and control pests and diseases, significantly improving the nutritional quality and flavor of vegetables grown hydroponically, thus achieving healthy hydroponic vegetable production. Through further improvements to the antibacterial agent, it can be gradually released into the nutrient solution, providing continuous antibacterial protection and further stabilizing the water quality of the nutrient solution.

[0018] Preferably, the vegetable is bok choy; more preferably, the vegetable is Shanghai bok choy, with the Latin name Brassica campestrisssp. Chinensis (L.).

[0019] The present invention also discloses a method for preparing the nutrient solution for hydroponic vegetables, comprising the following steps: mixing calcium nitrate tetrahydrate, ammonium nitrate, potassium nitrate, urea, sodium iron ethylenediaminetetraacetate, ammonium dihydrogen phosphate, magnesium sulfate heptahydrate, sodium molybdate and antibacterial agent evenly, and then adding water to achieve the mass concentration stated above.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] 1. The hydroponic vegetable nutrient solution of this invention can provide all the elements needed for vegetable growth, with a reasonable ratio, promoting vegetable growth and producing vegetables with high yield and excellent quality.

[0022] 2. The antibacterial agent of this invention can prevent the proliferation of microorganisms that lead to water quality deterioration, promote seedling growth and the accumulation of nutrients, and prevent and control pests and diseases, thereby improving the nutritional quality and flavor of vegetables in hydroponics and achieving healthy hydroponic vegetable production. Through further improvements to the antibacterial agent, it can be gradually released in the nutrient solution, continuously inhibiting bacteria in the nutrient solution and further stabilizing the water quality of the nutrient solution, avoiding the increased planting costs caused by frequent water changes. Detailed Implementation

[0023] Example 1

[0024] A method for preparing a nutrient solution for hydroponic vegetables includes the following steps: mixing 50g calcium nitrate tetrahydrate, 50g ammonium nitrate, 50g potassium nitrate, 20g urea, 10g ferric sodium ethylenediaminetetraacetate, 50g ammonium dihydrogen phosphate, 50g magnesium sulfate heptahydrate, 25g sodium molybdate, and 8g antibacterial agent evenly, then adding 1000g water and stirring until evenly mixed to obtain the nutrient solution for hydroponic vegetables.

[0025] The method for preparing the antibacterial agent includes the following steps:

[0026] S1. Dissolve 20g ursolic acid, 30g oleanolic acid, 6g zinc sulfate, 4g sodium bisulfite, and 4g citrate fatty acid ester in 300mL of water, and then stir and disperse at 3000rpm for 10min to obtain an antibacterial agent solution.

[0027] S2. After crushing 75g of straw through a 40-mesh sieve, add it to the antibacterial agent solution and stir at room temperature for 20 minutes. Then add 10g of sodium carboxymethyl cellulose and 20g of sesame gum. After high-speed shear dispersion treatment, add 20g of sodium tripolyphosphate and heat to 50℃ for 30 minutes. After the reaction is completed, cool to room temperature and centrifuge to collect the solids to obtain the antibacterial agent.

[0028] The sesame gum is carboxymethylated sesame gum, and its preparation method is as follows: at 30°C, 5g of sesame gum, 20mL of 1mol / L sodium hydroxide aqueous solution, and 200mL of anhydrous ethanol are mixed and stirred for 30min; 40g of monochloroacetic acid is added, and the mixture is stirred for 20min to obtain a mixed solution; the mixed solution is heated to 60°C and reacted for 10h; cooled to 30°C, filtered, and the filter cake is dissolved in 4 times its mass of water, and then anhydrous ethanol is added to precipitate it. After filtration, the filter cake is washed with methanol and dried at 50°C for 12h to obtain carboxymethylated sesame gum.

[0029] Example 2

[0030] A method for preparing a nutrient solution for hydroponic vegetables includes the following steps: mixing 50g calcium nitrate tetrahydrate, 50g ammonium nitrate, 50g potassium nitrate, 20g urea, 10g ferric sodium ethylenediaminetetraacetate, 50g ammonium dihydrogen phosphate, 50g magnesium sulfate heptahydrate, 25g sodium molybdate, and 8g antibacterial agent evenly, then adding 1000g water and stirring until evenly mixed to obtain the nutrient solution for hydroponic vegetables.

[0031] The method for preparing the antibacterial agent includes the following steps:

[0032] S1. Dissolve 20g ursolic acid, 30g oleanolic acid, 6g zinc sulfate, 4g sodium bisulfite, and 4g citrate fatty acid ester in 300mL of water, and then stir and disperse at 3000rpm for 10min to obtain an antibacterial agent solution.

[0033] S2. After crushing 75g of straw through a 40-mesh sieve, add it to the antibacterial agent solution and stir at room temperature for 20 minutes. Then add 10g of sodium carboxymethyl cellulose and 20g of sesame gum. After high-speed shear dispersion treatment, add 20g of sodium tripolyphosphate and heat to 50℃ for 30 minutes. After the reaction is completed, cool to room temperature and centrifuge to collect the solids to obtain the antibacterial agent.

[0034] Comparative Example 1

[0035] A method for preparing a nutrient solution for hydroponic vegetables includes the following steps: mixing 50g calcium nitrate tetrahydrate, 50g ammonium nitrate, 50g potassium nitrate, 20g urea, 10g ferric sodium ethylenediaminetetraacetate, 50g ammonium dihydrogen phosphate, 50g magnesium sulfate heptahydrate, 25g sodium molybdate, and 8g antibacterial agent evenly, then adding 1000g water and stirring until evenly mixed to obtain the nutrient solution for hydroponic vegetables.

[0036] The method for preparing the antibacterial agent includes the following steps:

[0037] S1. Dissolve 20g ursolic acid, 30g oleanolic acid, 6g zinc sulfate, 4g sodium bisulfite, and 4g citrate fatty acid ester in 300mL of water, and then stir and disperse at 3000rpm for 10min to obtain an antibacterial agent solution.

[0038] S2. After crushing 75g of straw through a 40-mesh sieve, add it to the antibacterial agent solution and stir at room temperature for 20 minutes. Then add 20g of sesame gum, disperse it by high-speed shearing, and then add 20g of sodium tripolyphosphate. Heat to 50℃ and react for 30 minutes. After the reaction is complete, cool to room temperature and centrifuge to collect the solid to obtain the antibacterial agent.

[0039] Comparative Example 2

[0040] A method for preparing a nutrient solution for hydroponic vegetables includes the following steps: mixing 50g calcium nitrate tetrahydrate, 50g ammonium nitrate, 50g potassium nitrate, 20g urea, 10g ferric sodium ethylenediaminetetraacetate, 50g ammonium dihydrogen phosphate, 50g magnesium sulfate heptahydrate, and 25g sodium molybdate evenly, then adding 1000ml of water and stirring until evenly mixed to obtain the nutrient solution for hydroponic vegetables.

[0041] Test case

[0042] The test subjects were the hydroponic vegetable nutrient solutions obtained in Examples 1-2 and Comparative Examples 1-2. Shanghai bok choy seeds were surface-sterilized with 1% sodium hypochlorite for 15 minutes, rinsed, and then soaked overnight in deionized water at 25°C. They were sown in a vermiculite-peat substrate and cultured. After 2-3 true leaves emerged, they were transferred to a transfer box containing hydroponic vegetable nutrient solution. Each treatment used 1L beakers (wrapped with black opaque tape), with 2 Shanghai bok choy plants planted in each beaker. No aeration was provided. Yield of Shanghai bok choy was measured at harvest after 45 days. The light exposure time in the incubator was 16 hours, and the light intensity was 300 μmol / m². 2 / s, daytime temperature 25℃, nighttime temperature 20℃, relative humidity 67%.

[0043] The test results are shown in Table 1:

[0044] Table 1. Results of Shanghai bok choy yield and quality test

[0045] As can be seen from the experimental data in Table 1, the Shanghai bok choy obtained using Example 1 had the best quality and yield. The difference between Example 1 and other examples and comparative examples is the addition of a different antibacterial agent. The antibacterial agent used in Example 1 is a carboxymethyl cellulose sodium and carboxymethylated sesame gum coated antibacterial agent, which allows the antibacterial agent to be gradually released in the nutrient solution, continuously inhibiting bacteria in the nutrient solution and further stabilizing the water quality of the nutrient solution, thereby promoting the healthy growth of vegetables and ensuring the quality and yield of vegetables.

[0046] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A nutrient solution for hydroponic vegetables, characterized by comprising, It includes the following components: calcium nitrate tetrahydrate, ammonium nitrate, potassium nitrate, urea, sodium iron ethylenediaminetetraacetate, ammonium dihydrogen phosphate, magnesium sulfate heptahydrate, sodium molybdate, antibacterial agent, and water.

2. The nutrient solution for hydroponic vegetables according to claim 1, characterized by, It comprises the following components by mass percentage: 0.1-10 wt% calcium nitrate tetrahydrate, 0.1-10 wt% ammonium nitrate, 0.1-10 wt% potassium nitrate, 0.1-5 wt% urea, 0.1-2 wt% sodium iron ethylenediaminetetraacetate, 0.1-10 wt% ammonium dihydrogen phosphate, 0.1-10 wt% magnesium sulfate heptahydrate, 0.1-5 wt% sodium molybdate, 0.01-1 wt% antibacterial agent, and the balance being water.

3. The nutrient solution for hydroponic vegetables according to claim 1 or 2, characterized by, The antibacterial agent is a mixture of ursolic acid, oleanolic acid, zinc sulfate, sodium bisulfite and citrate fatty acid ester.

4. The nutrient solution for hydroponic vegetables according to claim 3, characterized by, The mass ratio of ursolic acid, oleanolic acid, zinc sulfate, sodium bisulfite and citrate fatty acid ester is 1-3:2-4:0.1-1:0.1-0.5:0.1-0.

5.

5. The nutrient solution for hydroponic vegetables according to claim 3, characterized in that, The method for preparing the antibacterial agent includes the following steps: S1. Dissolve ursolic acid, oleanolic acid, zinc sulfate, sodium bisulfite, and citrate fatty acid ester in water, and then disperse them by high-speed stirring to obtain an antibacterial agent solution; S2. After crushing the straw, add it to the antibacterial agent solution, stir at room temperature, add sodium carboxymethyl cellulose and sesame gum, perform high-speed shear dispersion treatment, add sodium tripolyphosphate, heat to react, and centrifuge to collect the solids to obtain the antibacterial agent.

6. The nutrient solution for hydroponic vegetables according to claim 5, characterized in that, In step S2, the amount of straw used is 20-30 wt% of the antibacterial agent solution.

7. The nutrient solution for hydroponic vegetables according to claim 5, characterized in that, In step S2, the mass ratio of sodium carboxymethyl cellulose to sesame gum is 1-3:2-5.

8. The hydroponic vegetable nutrient solution according to claim 5, characterized in that, The condition for high-speed shearing is a rotation speed of 2000-3000 rpm.

9. The nutrient solution for hydroponic vegetables according to claim 5, characterized in that, The sesame gum is carboxymethylated sesame gum, and its preparation method is as follows: sesame gum, sodium hydroxide aqueous solution, and ethanol are mixed and stirred; monochloroacetic acid is added and stirred to obtain a mixed solution; the mixed solution is heated to react and obtain carboxymethylated sesame gum.

10. The method for preparing the nutrient solution for hydroponic vegetables according to any one of claims 1-9, characterized in that, Includes the following steps: The ingredients are calcium nitrate tetrahydrate, ammonium nitrate, potassium nitrate, urea, sodium iron ethylenediaminetetraacetate, ammonium dihydrogen phosphate, magnesium sulfate heptahydrate, sodium molybdate, and antibacterial agent. Water is then added to achieve the specified mass concentration.

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