Tea leaf fertilizer and preparation method thereof

Abstract

According to the tea leaf foliar fertilizer and the preparation method thereof, by optimizing the formula of the tea leaf foliar fertilizer and scientifically proportioning main nutrient elements and trace elements such as nitrogen, phosphorus and potassium, accumulation of substances contained in tea leaves is improved, so that the appearance quality and the nutritional ingredient balance of the tea leaves are improved; the stability and absorptivity of the fertilizer are improved, the nutrient loss is reduced, and the nutritional value and health benefits of the tea leaves are further improved. The trace elements are fully chelated by the corresponding chelating agents through PH layered regulation and control, precise proportioning and a distribution process, so that the problems of extrusion and inhibition between different elements and different chelating agents are avoided, and the absorption effect of the trace elements is ensured.

Description

Technical Field

[0001] The present invention relates to the field of tea tree planting, and particularly to a foliar fertilizer for tea leaves and a preparation method thereof. Background Art

[0002] As a globally widely consumed beverage, the quality and nutritional value of tea are directly related to the health of consumers and the competitiveness of the market. However, in the traditional tea planting and fertilization processes, there are some technical problems, which limit the improvement of tea quality and the increase of nutritional value.

[0003] Firstly, the insufficient accumulation of tea leaf internal substances is a common problem. Traditional fertilization methods often cannot provide the comprehensive nutrients required for tea growth, resulting in insufficient contents of tea leaf internal substances such as tea polyphenols and amino acids, affecting the taste and health benefits of tea.

[0004] Secondly, the poor appearance quality of tea leaves is also a prominent problem. Due to uneven fertilization, the tea leaves have different sizes and uneven colors, which directly affects the market value of tea and the purchasing intention of consumers.

[0005] Furthermore, the unbalanced nutritional components of tea leaves are also a long-existing problem. Traditional fertilization methods often neglect the importance of trace elements, resulting in insufficient contents of trace elements such as iron, zinc, and magnesium in tea leaves, affecting the nutritional value and health benefits of tea.

[0006] In addition, the impact of tea leaf nutrient deficiency on quality is also a problem that cannot be ignored. Due to the lack of certain trace elements in the soil, tea trees cannot normally absorb these elements, resulting in tea leaf nutrient deficiency, affecting the quality and yield of tea. Summary of the Invention

[0007] The purpose of the present invention is to provide a foliar fertilizer for tea leaves to solve the technical problems in the prior art that the accumulation of tea leaf internal substances is insufficient and the tea leaf quality is insufficient due to the lack of trace elements; the purpose of the present invention is also to provide a preparation method of the foliar fertilizer for tea leaves.

[0008] To solve the above technical problems, the technical solution of a foliar fertilizer for tea leaves in the present invention is as follows:

[0009] A foliar fertilizer for tea leaves comprises components in the following weight ratios,

[0010] Nitrogen, 15% - 20%;

[0011] Phosphorus pentoxide, 8% - 12%;

[0012] Potassium oxide, 10% - 15%;

[0013] Iron, 0.1% - 0.3%;

[0014] Zinc, 0.05% - 0.15%;

[0015] Magnesium, 0.5% - 1.5%;

[0016] Citric acid, 1% - 10%;

[0017] Synthetic chelating agent, 0.15% - 0.5%;

[0018] Natural chelating agent, 0.5% - 20%;

[0019] Water, 30% - 60%.

[0020] Furthermore, the natural chelating agent is humic acid used for chelating magnesium.

[0021] Furthermore, the synthetic chelating agent includes EDDHA for chelating iron and EDTA for chelating zinc. The weight ratio of EDDHA in the tea foliar fertilizer is 0.1% - 0.35%, and the weight ratio of EDTA in the tea foliar fertilizer is 0.05% - 0.2%.

[0022] Furthermore, it includes components with the following weight ratios,

[0023] Nitrogen, 18%;

[0024] Phosphorus pentoxide, 10%;

[0025] Potassium oxide, 12%;

[0026] Iron, 0.2%;

[0027] Zinc, 0.1%;

[0028] Magnesium, 1%;

[0029] Citric acid, 7%;

[0030] Synthetic chelating agent, 0.35%;

[0031] Natural chelating agent, 5%;

[0032] Water, 46.35%.

[0033] In the present invention, the technical solution of the preparation method of the tea foliar fertilizer is as follows:

[0034] In the first step, the trace elements iron, zinc and magnesium are chelated separately,

[0035] Specifically, EDDHA is used to chelate iron in an alkaline environment with a pH value of 7 - 8 to obtain a first solution. EDTA is used to chelate zinc in a weakly acidic environment with a pH value of 5.5 - 7 to obtain a second solution. Humic acid is used to chelate magnesium in a weakly acidic environment with a pH value of 5.5 - 7 to obtain a third solution.

[0036] In the second step, in a container, water, nitrogen, phosphorus pentoxide, and potassium oxide are sequentially added. Citric acid is added to adjust the pH value in the container to 6 - 7. The first solution, the second solution, and the third solution from the first step are sequentially added into the container.

[0037] In the third step, in the container, the pH value of the solution is adjusted to 6.75 - 7 by increasing the amount of citric acid.

[0038] Furthermore, in the first solution, the dosage of EDDHA is 1.1 - 1.2 times the molar amount of iron; in the second solution, the dosage of EDTA is 1.05 - 1.1 times the molar amount of zinc; in the third solution, the dosage of humic acid is 23 - 30 times the molar amount of magnesium.

[0039] The beneficial effects of the present invention are as follows: In the present invention, by optimizing the formula of the foliar fertilizer for tea, scientifically proportioning the main nutrient elements such as nitrogen, phosphorus, and potassium and trace elements, the accumulation of the substances contained in the tea is improved, thereby improving the appearance quality and the balance of nutritional components of the tea. The chelation process is adopted to improve the stability and absorption rate of the fertilizer, reduce the nutrient loss, and further improve the nutritional value and health benefits of the tea.

[0040] The water solubility of potassium is very high and it can be well absorbed by plants without the use of a chelating agent. However, when using the chelation process to chelate iron, zinc, and magnesium, there is a new problem. That is, the role of the chelating agent is to form a stable chelate with metal ions to prevent these ions from precipitating or binding with other substances and becoming ineffective, thereby improving the absorption efficiency of trace elements by plants. However, different chelating agents have different chelating abilities for different metal elements. If EDTA (ethylenediaminetetraacetic acid) is used for all three metal elements, the competition between metal ions will be particularly severe. High-concentration metals (such as Fe 3+ ) will inhibit the binding of the chelating agent to low-concentration metals (Zn 2+ ), and will even affect the chelating effect of magnesium ions. In the present invention, different metal elements are first chelated with the corresponding chelating agents to form stable solutions in different pH environments and then mixed, avoiding the competition between metal ions, ensuring the chelating effects of each metal ion, and further ensuring the absorption effects of each metal ion by the tea leaves. Detailed implementation mode

[0041] To facilitate the understanding of the present invention, the present invention will be described in more detail below in conjunction with specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosed content of the present invention more thorough and comprehensive.

[0042] It should be noted that unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not used to limit the present invention.

[0043] An embodiment of a tea foliar fertilizer in the present invention:

[0044] Nitrogen, 15% - 20%;

[0045] Phosphorus pentoxide, 8% - 12%;

[0046] Potassium oxide, 10% - 15%;

[0047] Iron, 0.1% - 0.3%;

[0048] Zinc, 0.05% - 0.15%;

[0049] Magnesium, 0.5% - 1.5%;

[0050] Citric acid, 1% - 10%;

[0051] Synthetic chelating agent, 0.15% - 0.5%;

[0052] Natural chelating agent, 0.5% - 20%;

[0053] Water, 30% - 60%.

[0054] The natural chelating agent is humic acid used for chelating magnesium,

[0055] The synthetic chelating agent includes EDDHA for chelating iron and EDTA for chelating zinc. The weight ratio of EDDHA in the tea foliar fertilizer is 0.1% - 0.35%, and the weight ratio of EDTA in the tea foliar fertilizer is 0.05% - 0.2%.

[0056] As a preferred embodiment:

[0057] The tea foliar fertilizer includes the following components in weight ratio,

[0058] Nitrogen, 18%;

[0059] Phosphorus pentoxide, 10%;

[0060] Potassium oxide, 12%;

[0061] Iron, 0.2%;

[0062] Zinc, 0.1%;

[0063] Magnesium, 1%;

[0064] Citric acid, 7%;

[0065] Synthetic chelating agent, 0.35%;

[0066] Natural chelating agent, 5%;

[0067] Water, 46.35%.

[0068] In the present invention, nitrogen, phosphorus and potassium are used as the main nutrient elements for leaf growth, and iron, zinc and magnesium are used as the trace elements for leaf growth, which can increase the accumulation of substances in tea leaves, thereby improving the appearance quality and nutritional component balance of tea leaves. The difficulty of the scheme lies in how the trace elements can be effectively absorbed by tea leaves.

[0069] The function of the chelating agent is to form stable chelates with metal ions to prevent these ions from precipitating or binding with other substances and becoming ineffective, thereby improving the absorption efficiency of plants for trace elements. When chelating multiple metal elements, how to avoid the competition of the chelating agent among different elements and ensure the chelating effect among various metal elements is the key innovation of the present invention.

[0070] Therefore, the technical scheme of the preparation method of the tea foliar fertilizer in the present invention is as follows:

[0071] In the first step, the trace elements iron, zinc and magnesium are chelated separately,

[0072] Specifically, EDDHA is used to chelate iron in an alkaline environment with a pH value of 7 - 8 to obtain the first solution, EDTA is used to chelate zinc in a weakly acidic environment with a pH value of 5.5 - 7 to obtain the second solution, and humic acid is used to chelate magnesium in a weakly acidic environment with a pH value of 5.5 - 7 to obtain the third solution;

[0073] In the second step, in a container, water, nitrogen, phosphorus pentoxide and potassium oxide are added in sequence, citric acid is added, the pH value in the container is adjusted to 6 - 7, and the first solution, the second solution and the third solution in the first step are added to the container in sequence.

[0074] In the third step, in the container, the pH value of the solution is adjusted to 6.75 - 7 by increasing citric acid.

[0075] Furthermore, in the first solution, the dosage of EDDHA is 1.1 - 1.2 times the molar amount of iron; in the second solution, the dosage of EDTA is 1.05 - 1.1 times the molar amount of zinc; in the third solution, the dosage of humic acid is 23 - 30 times the molar amount of magnesium.

[0076] EDTA is suitable for neutral to weakly acidic environments and has a chelating effect on both iron and zinc. Its disadvantage is the relatively high cost. When using this chelating agent for both iron and zinc simultaneously, high concentrations of the metal Fe 3+ will inhibit the binding of the chelating agent to the low-concentration metal zinc Zn 2+ . EDDHA (ethylenediaminedi-o-hydroxyphenylacetic acid) has a relatively high stability constant for iron (logK = 35), but insufficient affinity for zinc. At the same time, the stability constants of both EDTA and EDDHA for magnesium are not high, that is, their affinities for magnesium are insufficient.

[0077] Therefore, the final selected solution is to use humic acid to chelate magnesium. Humic acid can improve mobility by binding with Mg through functional groups such as hydroxyl groups 2+ ; use EDTA to chelate zinc, and use EDDHA to chelate iron. Then, how to avoid the influence between different chelating agents and different metal elements has become a new problem.

[0078] For this reason, we innovatively proposed a new process, that is, to avoid the above problems through methods such as pH layer control, precise ratio, and distribution process.

[0079] The theoretical loading capacity of EDTA is that one molecule of chelating agent binds one metal ion; the theoretical loading capacity of EDDHA is that one molecule of chelating agent binds one metal ion. Excessive metal will cause precipitation of unchelated ions

[0080] Specifically, EDDHA pre-reacts with Fe 3+ under alkaline conditions to form a stable chelate. The usage amount of EDDHA is slightly greater than that of Fe 3+ , and there will be no excessive chelated ions remaining; EDTA chelates with Zn 2+ alone under weakly acidic conditions to form a stable chelate. The usage amount of EDTA is slightly greater than that of Zn 2+ , and there will be no excessive chelated ions remaining; humic acid chelates with magnesium alone. The usage amount of humic acid is relatively large to ensure complete chelation of all magnesium. The excess humic acid will not chelate iron and zinc, and the excess humic acid can also effectively enhance the resistance of the tea tree cell wall and improve the tea tree's resistance to drought, low temperature, and pests and diseases. When finally forming the mixed solution, the pH value of the mixed solution is adjusted by citric acid and water so that each chelating agent is in a pH range where it can exert its effect, ultimately ensuring the absorption effect of each trace element.

[0081] In the above description of this specification, unless otherwise clearly specified and defined, terms such as "fixed", "installed", "connected" or "coupled" should be understood in a broad sense. For example, for the term "connected", it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, or it can be the communication inside two components or the interaction relationship between two components. Therefore, unless otherwise clearly defined in this specification, those skilled in the art can understand the specific meanings of the above terms in the present invention according to specific circumstances.

[0082] According to the above description of this specification, those skilled in the art can also understand the terms used as follows. For example, terms indicating orientation or position relationship such as "upper", "lower", "front", "rear", "left", "right", "length", "width", "thickness", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", "center", "longitudinal", "transverse", "clockwise" or "counterclockwise" are based on the orientation or position relationship shown in this specification. They are only for the purpose of facilitating the description of the solution of the present invention and simplifying the description, rather than explicitly or implicitly indicating that the device or component involved must have the specific orientation, be constructed and operated in the specific orientation. Therefore, the above terms of orientation or position relationship cannot be understood or interpreted as a limitation to the solution of the present invention.

[0083] In addition, terms such as "first" or "second" used in this specification to refer to numbers or ordinals are only for descriptive purposes and cannot be understood as explicitly or implicitly indicating relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this specification, the meaning of "a plurality" is at least two, such as two, three or more, etc., unless otherwise clearly and specifically defined.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A tea foliar fertilizer, characterized in that: Comprising the following ingredients in weight ratio, Nitrogen, 15%-20%; Phosphorus pentoxide, 8%-12%; Potassium oxide, 10%-15%; Iron, 0.1%-0.3%; Zinc, 0.05%-0.15%; Magnesium, 0.5%-1.5%; Citric acid, 1%-10%; Synthetic chelating agents, 0.15%-0.5%; Natural chelating agent, 0.5%-20%; Water, 30%-60%.

2. Tea foliar fertilizer according to claim 1, characterized in that: The natural chelating agent is humic acid for chelating magnesium.

3. Tea leaf fertilizer according to claim 1, characterized in that: The synthetic chelating agent comprises EDDHA for chelating iron and EDTA for chelating zinc. The weight ratio of EDDHA to the tea foliar fertilizer is 0.1%-0.35%, and the weight ratio of EDTA to the tea foliar fertilizer is 0.05%-0.2%.

4. The tea foliar fertilizer according to any one of claims 1 to 3, characterized in that: Comprising the following ingredients in weight ratio, nitrogen, 18%; Phosphorus pentoxide, 10%; Potassium oxide, 12%; Iron, 0.2%; Zinc, 0.1%; Magnesium, 1%; Citric acid, 7%; synthetic chelating agent, 0.35%; Natural chelating agent, 5%; Water, 46.35%.

5. A method for preparing the tea foliar fertilizer according to any one of claims 1 to 4, characterized in that: The first step is to chelate the trace elements iron, zinc and magnesium separately. Specifically, EDDHA is used to chelate iron in an alkaline environment, the pH value of the alkaline environment is 7-8, to obtain a first solution, EDTA is used to chelate zinc in a weakly acidic environment, the pH value of the weakly acidic environment is 5.5-7, to obtain a second solution, humic acid is used to chelate magnesium in a weakly acidic environment, to obtain a third solution, the pH value of the weakly acidic environment is 5.5-7; In the second step, water, nitrogen, phosphorus pentoxide and potassium oxide are added sequentially in a container, citric acid is added, the pH value in the container is adjusted to 6-7, and the first solution, the second solution and the third solution in the first step are added sequentially into the container. The third step is to adjust the pH value of the solution to 6.75-7 in the container by adding citric acid.

6. The preparation method according to claim 5, characterized in that: In the first solution, the amount of EDDHA is 1.1 to 1.2 times the molar amount of iron; in the second solution, the amount of EDTA is 1.05 to 1.1 times the molar amount of zinc; in the third solution, the amount of humic acid is 23 to 30 times the molar amount of magnesium.