Irrigation and fertilization composition and application method thereof

Abstract

The invention discloses an irrigation and fertilization composition and an application method thereof. The irrigation and fertilization composition is used for maintaining or increasing the single fruit weight and mineral element content of crops. The irrigation and fertilization composition comprises hydrogen-rich water, a compound fertilizer and a trace element fertilizer. In the time period of applying the irrigation and fertilization composition, the hydrogen concentration of an outlet of the hydrogen-rich water is kept within the range of 300-1200 ppb. The fertigation composition is beneficial to improving the problem of loss of soil fertility and nutrient balance caused by continuous use of traditional fertilizers.

Description

Fertigation composition and application method thereof Technical Field

[0001] The present invention relates to the field of agricultural technology, and in particular to a fertigation composition and an application method thereof, and more particularly to a method for applying the fertigation composition to crops such as blueberries, strawberries or tomatoes. Background Art

[0002] Blueberries are small perennial berries belonging to the genus Vaccinium in the Ericaceae family. They have a sweet and sour taste and are rich in antioxidants (such as anthocyanins) and various minerals. Therefore, the Food and Agriculture Organization of the United Nations (FAO) lists blueberries as one of the five healthiest foods for humans.

[0003] Compared to other fruits, blueberries are oligotrophic. Appropriate fertilization can not only effectively increase blueberry yields but also improve fruit quality. Blueberries are extremely sensitive to fertilizer; either excessive or insufficient fertilization can hinder their growth. Too little fertilization can severely impact flower bud differentiation, leading to a lack of flowering or poor bud development. Excessive fertilization can inhibit growth, even leading to toxicity and death, and negatively impact the soil.

[0004] Water-fertilizer integration is an agronomic measure that couples irrigation and fertilization, which can effectively improve the utilization rate of water and fertilizer. The Chinese invention patent with application number CN202111370611.1 discloses a method for precise water-fertilizer integration fertilization of blueberries, in which the fertilizers applied mainly include nitrogen, phosphorus and potassium fertilizers. However, the long-term application of only compound fertilizers can easily lead to an imbalance of nutrient elements in plants. The Chinese invention patent with application number CN202011286229.8 discloses a method for growing blueberries with a high anthocyanin content. By increasing the application of organic matter and sulfur powder, the organic matter content of the soil reaches 7 to 15%. Special fertilizers are applied to the cultivated blueberry seedlings, which mainly include peat, urea, potassium dihydrogen phosphate, distiller's grains, tofu dregs and humic acid to increase the anthocyanin content.

[0005] Blueberries are best grown in acidic soils with a pH of 4.0 to 5.5. The roots of blueberries are very sensitive to soil pH. Too high a soil pH will reduce the blueberry plant's absorption of nitrogen and mineral elements such as iron, zinc, and magnesium. First, the presence and availability of various mineral nutrients in the soil vary with pH. Under higher pH conditions, the NH4 +-N is easily nitrified into NO3-N by microorganisms, resulting in insufficient available nitrogen in blueberries. Insufficient nitrogen can lead to a series of problems such as small blueberry fruits, small numbers, hard skin, yellowing and loss of green leaves, and short plants. Second, soil pH also affects the accumulation of anthocyanins in blueberry fruits. Since anthocyanins are mainly composed of ketone compounds, the higher the alkalinity of the soil, the easier it is for anthocyanins to degrade. Third, too high or too low pH values ​​are not conducive to leaf photosynthesis and the accumulation of organic matter. Soil pH stress can cause blueberry plants to be deficient or suffer from ion poisoning, reduce anthocyanin accumulation and growth, and reduce root activity, resulting in reduced yield.

[0006] The most common method for improving soil quality in blueberry cultivation is to apply sulfate or phosphate fertilizers. However, these fertilizers have drawbacks such as delayed action, short duration of action, and rapid acid rebound, which negatively impact blueberry cultivation. Long-term sulfur use can also reduce soil microbial diversity and community richness, and cause soil compaction.

[0007] Hydrogen is a biosafe gaseous signaling molecule that can regulate plant growth and development. Chinese invention patent number ZL201210154005.0 discloses a hydrogen-rich liquid plant growth regulator with a hydrogen saturation of 0.1 to 100% and a solvent consisting of Hoagland nutrient solution, Kimura B nutrient solution, TAP nutrient solution, or MS culture medium. While these formulations are suitable for short-term hydroponic cultivation of plant seedlings in the laboratory, they are difficult to meet the needs of agricultural production. Chinese invention patent number ZL 202110791343.4 discloses a method for combining hydrogen-rich water, pesticides, and fertilizers. Irrigation with hydrogen-rich water can increase the content of various aromatic substances in fruits and vegetables, enhance the accumulation of volatile substances, and increase the expression of related regulatory genes, thereby enhancing the flavor integrity of fruits and vegetables. When used in combination with pesticides and fertilizers, it can alleviate the adverse effects of pesticides and fertilizers on the flavor of fruits and vegetables.

[0008] The present application aims to design a targeted fertilization composition suitable for blueberries, which can not only exert the biological effect of hydrogen but also reduce the use of sulfate or phosphate soil acidifiers.

[0009] Disclosure of the invention

[0010] The present invention aims to provide a fertigation composition and a fertilization method for crops such as blueberries, strawberries, or tomatoes. The fertigation composition can effectively maintain or increase the weight of individual fruits and the content of specific mineral elements in the crops.

[0011] The first aspect of the present invention provides a fertigation composition for maintaining or increasing the mineral element content of crops, the fertigation composition comprising hydrogen-rich water, a compound fertilizer, and a trace element fertilizer, wherein the trace element fertilizer comprises one or more of boron, calcium, magnesium, iron, zinc, copper, manganese, and molybdenum;

[0012] During the period of applying the fertigation composition, the outlet hydrogen concentration of the hydrogen-rich water is maintained within the range of 300 to 1200 ppb.

[0013] Furthermore, the outlet hydrogen concentration of hydrogen-rich water is maintained within the range of 500~1200ppb.

[0014] Furthermore, in the fertigation composition, whenever the first predetermined amount of trace element fertilizer is reduced, the outlet hydrogen concentration of the hydrogen-rich water needs to be increased to a second predetermined amount.

[0015] Furthermore, the second predetermined amount increases as the first predetermined amount increases.

[0016] Furthermore, the increase of the first predetermined amount is in a linear relationship with the increase of the second predetermined amount.

[0017] Further, when the first predetermined amount is 20% to 50%, the second predetermined amount is 500 ppb to 1200 ppb.

[0018] Further, when the first predetermined amount is 20%, the second predetermined amount is 500 ppb.

[0019] Further, when the first predetermined amount is 50%, the second predetermined amount is 1200 ppb.

[0020] Furthermore, the pH value of the fertigation composition is 4.0-5.0.

[0021] Furthermore, the compound fertilizer includes at least one or more of nitrogen, phosphorus or potassium.

[0022] Furthermore, the nitrogen element comes from ammonium nitrate and / or ammonium sulfate.

[0023] Furthermore, the phosphorus element contained comes from monoammonium phosphate and / or diammonium phosphate.

[0024] Furthermore, the potassium element contained comes from potassium sulfate, potassium dihydrogen phosphate and / or potassium fulvic acid.

[0025] Furthermore, the boron element contained in the trace element fertilizer comes from boric acid and / or borax.

[0026] Furthermore, the calcium element contained in the trace element fertilizer comes from calcium sulfate, calcium carbonate and / or chelated calcium.

[0027] Furthermore, the magnesium element contained in the trace element fertilizer comes from magnesium sulfate and / or EDTA chelated magnesium.

[0028] Furthermore, the iron element contained in the trace element fertilizer comes from ferrous sulfate and / or EDTA chelated iron.

[0029] Furthermore, the zinc element contained in the trace element fertilizer comes from zinc sulfate and / or EDTA chelated zinc.

[0030] Furthermore, the copper element contained in the trace element fertilizer comes from copper sulfate and / or EDTA chelated copper.

[0031] Furthermore, the manganese element contained in the trace element fertilizer comes from manganese sulfate and / or EDTA chelated manganese.

[0032] Furthermore, the molybdenum element contained in the trace element fertilizer comes from ammonium molybdate.

[0033] The second aspect of the present application provides a method for applying the fertigation composition according to the first aspect:

[0034] From February to April, the fertigation composition was applied at a rate of 95-200 mg / L of NH4 + 3800~7750 mg / L NO3 - 500~1050 mg / L PO4 3- , 800~1600 mg / L K + , 500~1000 mg / L of Ca 2+ , 400~830 mg / L SO4 2- , 100~200 mg / L Fe 3+ 12.5~25 mg / L Mg 2+ , 0.65~1.3 mg / L of Mn 2+ , 0.15~0.3 mg / L Zn 2+ , 0.01~0.02 mg / L Cu 2+ and 0.015~0.03 mg / L MoO4 2- ;

[0035] From May to June, the fertigation composition was applied at a rate of 1800-3600 mg / L of NH4 + , 900~1800 mg / L NO3 - , 1000~2000 mg / L K + , 18~36 mg / L Ca 2+ 10~20 mg / L BO33- , 10~20 mg / L SO4 2- , 0.6~1.2 mg / L Fe 3+ 135~270 mg / L Mg 2+ , 15~30 mg / L Mn 2+ , 18~36 mg / L Zn 2+ , 5~10 mg / L Cu 2+ and 7.5~15 mg / L MoO4 2- .

[0036] Furthermore, from February to April, the ratio of the outlet hydrogen concentration of the hydrogen-rich water to the amount of fertigation composition applied is greater than 15.8 ppb / g, preferably greater than 37.9 ppb / g.

[0037] Furthermore, from February to April, the fertigation composition is applied at an amount of 0.5 to 2.5 liters per plant, 1 to 2 times per day.

[0038] Furthermore, from May to June, the ratio of the outlet hydrogen concentration of the hydrogen-rich water to the application amount of the fertigation composition is greater than 18.3 ppb / g, preferably greater than 44.0 ppb / g.

[0039] Furthermore, from May to June, the fertigation composition is applied at an amount of 2.5 to 3.5 liters per plant, 2 to 3 times a day.

[0040] Compared with the prior art, the technical solution provided by the present invention has the following advantages:

[0041] 1. By adding a specific concentration of hydrogen-rich water to the fertigation composition, the application amount of trace element fertilizer is reduced, while maintaining or improving the yield, mineral element content and nutritional quality of crops.

[0042] 2. The fertigation composition improves fertilizer utilization, reduces the application of traditional soil acidity regulators, and improves the problems of soil fertility loss and nutrient loss caused by the continuous use of traditional fertilizers.

[0043]

[0044] Best Mode for Carrying Out the Invention

[0045] The present invention is not limited to such embodiments described below, and the technical idea of ​​the present invention can be implemented in combination with other known technologies or other technologies having the same functions as those known technologies.

[0046] As used herein, the term "farmland" refers to land used for agricultural production and cultivated fields, including but not limited to land or fields planted with food crops, cash crops (e.g., oilseed crops, vegetable crops, flowers, forage, fruit trees), industrial raw material crops, feed crops, and traditional Chinese medicine. Preferably, it refers to land where plants (e.g., cereals, vegetables, cotton, flax, etc.) can be grown in large quantities or harvested on a large scale for profit or food. More preferably, it refers to land or fields planted with rice, corn, beans, potatoes, barley, broad beans, wheat, oilseeds, turnips, mustard, peanuts, sesame, hemp, sunflowers, radishes, cabbage, celery, leeks, garlic, onions, carrots, cucumbers, lotus seeds, Jerusalem artichokes, sword beans, cilantro, lettuce, daylilies, peppers, cucumbers, tomatoes, and coriander. In the present invention, the term "field" is equivalent to "farmland" or "field," and there are no particular requirements for the area, size, or shape of the field or farmland.

[0047] The details of farmland design may vary in different regions depending on the size of the farmland, location, climate, sunlight, experience of local farmers, and crop types. The purpose of this invention is to provide a guiding principle for combining hydrogen-rich water irrigation and fertilization, and is not intended to limit adjustments based on the experience of farmers and the specific needs of crops.

[0048] As used herein, "hydrogen-rich water (HRW)" or "hydrogen water" refers to water rich in hydrogen. At atmospheric pressure and 20°C, the maximum concentration of hydrogen dissolved in water is 1.6 ppm (1600 ppb), meaning that a maximum of 1.6 mg of hydrogen can be dissolved per kilogram of water, reaching saturation.

[0049] To increase the solubility and residence time of hydrogen in water, nanobubble technology is combined with hydrogen-enriched water. Hydrogen produced by electrolysis or from cylinders is used as the gas source and dissolved in water using a nanobubble hydrogen-enriched water generator to produce nanobubble hydrogen-enriched water. In comparison, hydrogen-enriched water produced by directly passing hydrogen into water has a much shorter half-life of only about one to two hours, resulting in a very short residence time. Nanobubble hydrogen water has a longer half-life, making it suitable for the practical needs of large, time-consuming irrigation applications in agricultural production.

[0050] The dissolved hydrogen concentration of nanobubble hydrogen water was measured using a dissolved hydrogen meter ENH-2000 (TRUSTLEX, Japan) calibrated with gas chromatography.

[0051] As used herein, "the outlet hydrogen concentration of hydrogen-rich water" refers to the dissolved hydrogen concentration measured at the outlet of the hydrogen-rich water. Although taking into account the escape of hydrogen, it is known to those skilled in the art that the concentration of hydrogen water irrigated in the farmland can be made as close as possible to the dissolved hydrogen concentration measured at the outlet by continuously adding hydrogen water, for example, an outlet concentration of more than 80%, preferably an outlet concentration of more than 85%, more preferably an outlet concentration of more than 90%, and most preferably an outlet concentration of 95% to 99.9%. It should be noted that, in view of the escape characteristics of hydrogen and the limitations of the detection means, the outlet hydrogen concentrations (such as 300ppb, 500ppb, 700ppb, etc.) described herein are allowed to have a certain numerical floating range. The main purpose of this article is to explore the influence of the changing trend of the concentration of hydrogen-rich water on the biological effect of the fertigation composition. It can be known to those skilled in the art that the reasonable range of fluctuations near the numerical point of the outlet hydrogen concentration of a particular hydrogen-rich water can be regarded as exerting the same degree of biological effect.

[0052] The "period of fertigation composition application" herein refers to the period of time during which the hydrogen water concentration in the farmland reaches or exceeds the minimum value required by the present invention by applying the fertigation composition. This period of time can be either continuous or intermittent.

[0053] In this article, "fertilizer" refers to substances that directly or indirectly provide nutrients to crops, improve soil properties, and ultimately increase crop yield and quality. Fertilizers can be classified in various ways. For example, based on their physical properties, they can be divided into solid fertilizers, liquid fertilizers, and gaseous fertilizers. Based on the mode of action, they can be divided into fast-acting fertilizers and slow-acting fertilizers. Based on the nutrients they contain, they can be divided into single-element fertilizers and compound fertilizers (multi-nutrient fertilizers). Based on their chemical composition, they can be divided into organic fertilizers, inorganic fertilizers, and organic-inorganic fertilizers.

[0054] In this article, "microelement fertilizer" refers to fertilizers that contain one or more essential elements for plant growth, but are required in very small quantities, such as boron fertilizer, manganese fertilizer, zinc fertilizer, copper fertilizer, molybdenum fertilizer, etc. Hereinafter, it will be referred to as micro-fertilizer.

[0055] In this article, "compound fertilizer" refers to a fertilizer made by dry mixing at least two of the three nutrients, nitrogen, phosphorus, and potassium, in specified amounts. It can also be called nitrogen, phosphorus, and potassium fertilizer.

[0056] The fertigation composition herein combines irrigation and fertilization with the help of the Fetigation technology. An exemplary fertigation technology includes, first, preparing soluble solid fertilizers or liquid fertilizers into a fertilizer solution according to the soil nutrient content and the fertilizer requirements of the crops. Secondly, a fertilizer applicator is connected to the main pipe of the irrigation water, and the fertilizer solution is injected into the main pipe after reasonable proportioning and mixed with the irrigation water. Then, the irrigation water and hydrogen are blended through the nanobubble hydrogen-rich water generation device, and drip irrigation is formed through the irrigation pipes and drippers to evenly, regularly and quantitatively infiltrate the crop roots. It is known to those skilled in the art that in the practice of farmland irrigation, the total amount of irrigation water is much higher than the amount of fertilizer solution, so the amount of fertigation composition applied herein can be considered to be approximately equal to the total amount of irrigation water.

[0057] The first predetermined amount herein refers to a percentage reduction in the amount of trace element fertilizer actually applied compared to the amount of trace element fertilizer applied under a baseline condition. The first predetermined amount is a unitless value representing a reduction range.

[0058] The second predetermined amount herein refers to the outlet hydrogen concentration value of the hydrogen-rich water finally applied.

[0059] The method for determining the mineral element content in blueberry fruit is provided in the reference Chen Z, Xie Y, Gu Q, et al. The AtrbohF-dependent regulation of ROS signaling is required for melatonin-induced salinity tolerance in Arabidopsis. Free Radical Biology and Medicine, 2017, 108: 465-477.

[0060] The blueberry cultivation described in the following examples of the present invention was carried out at the blueberry orchard in Qingxi Country Park, Shanghai. "Sapphire" blueberry seedlings were purchased from a Shanghai seed market. The conventional fertilization regimen for this blueberry orchard is shown in Table 1.

[0061] In the following examples, the amount of trace element fertilizer used according to this conventional fertilization scheme is defined as "100%" application amount.

[0062] Table 1 Common fertilization schemes

[0063] Fertilization stage Compound fertilizer dosage (mg / L plant) / time Trace element fertilizer dosage (mg / L plant) / time Fertilization times (times / day) February to early March NH4 + :190 NO3 - :7752 PO4 3- :1036 K + :1591Ca 2+ :1032 Mg 2+ :24.9 Fe 3+ :199 Mn 2+ :1.32 Zn 2+ :0.303 Cu 2+ :0.022 BO3 3- :0 MoO4 2- :0.03 SO4 2- :8281 Mid-March to early April NH4 + :190 NO3 - :7752 PO4 3- :1036 K + :1591Ca 2+ :1032 Mg 2+ :24.9 Fe 3+ :199 Mn 2+ :1.32 Zn 2+ :0.303 Cu 2+ :0.022 BO3 3- :0 MoO4 2- :0.03 SO4 2- : NH4 from 82825 to mid-June + :3583 NO3 - :1795 PO4 3- :0K + :1997Ca 2+ :35.6 Mg 2+ :270 Fe 3+ :1.19 Mn 2+ :30.2 Zn 2+ :36.3 Cu 2+ :10.1 BO3 3- :20.2 MoO4 2- :14.9 SO4 2- :213 Example

[0064] In this embodiment, the soil for growing blueberries is organic soil with a pH value of about 4.7.

[0065] Each group below has 14 rows of blueberries, with 66 pots of blueberries in each row, for a total of 924 pots of blueberry plants.

[0066] The irrigation method settings for each group are as follows:

[0067] 1) Ordinary water irrigation. No fertilizer is applied.

[0068] 2) Nanobubble hydrogen water irrigation. During irrigation, the outlet hydrogen concentration of hydrogen-rich water was approximately 300 ppb. No fertilizer was applied.

[0069] 3) Nanobubble hydrogen water irrigation. During irrigation, the outlet hydrogen concentration of hydrogen-rich water was approximately 500 ppb. No fertilizer was applied.

[0070] 4) Nanobubble hydrogen water irrigation. During irrigation, the outlet hydrogen concentration of hydrogen-rich water was approximately 1200 ppb. No fertilizer was applied.

[0071] 5) Nanobubble hydrogen water irrigation. During irrigation, the outlet hydrogen concentration of hydrogen-rich water was approximately 1500 ppb. No fertilizer was applied.

[0072] 6) Ordinary water irrigation. Fertilization program follows the conventional fertilization program in Table 1.

[0073] 7) Nanobubble hydrogen water irrigation. During irrigation, the outlet hydrogen concentration of the hydrogen-rich water was approximately 300 ppb. Fertilization was carried out according to the conventional fertilization plan in Table 1.

[0074] 8) Nanobubble hydrogen water irrigation. During irrigation, the outlet hydrogen concentration of the hydrogen-rich water was approximately 500 ppb. Fertilization was carried out according to the conventional fertilization plan in Table 1.

[0075] 9) Nanobubble hydrogen water irrigation. During irrigation, the outlet hydrogen concentration of the hydrogen-rich water was approximately 1200 ppb. Fertilization was carried out according to the conventional fertilization plan in Table 1.

[0076] 10) Nanobubble hydrogen water irrigation. During irrigation, the outlet hydrogen concentration of the hydrogen-rich water was approximately 1500 ppb. Fertilization was carried out according to the conventional fertilization plan in Table 1.

[0077] 11) Conventional water irrigation. Adjust the conventional fertilization plan in Table 1, maintaining the same application rate of compound fertilizer and reducing the application rate of trace element fertilizer by 20%. The total amount of irrigation water and the number of fertilization applications remain unchanged.

[0078] 12) Nanobubble hydrogen water irrigation. During irrigation, the hydrogen concentration of the hydrogen-rich water outlet was approximately 300 ppb. The conventional fertilization schedule in Table 1 was adjusted, with the compound fertilizer rate remaining unchanged and the trace element fertilizer rate reduced by 20%. The total irrigation water volume and fertilization frequency remained unchanged.

[0079] 13) Nanobubble hydrogen water irrigation. During irrigation, the hydrogen concentration of the hydrogen-rich water outlet was approximately 500 ppb. The conventional fertilization schedule in Table 1 was adjusted, with the compound fertilizer rate remaining unchanged and the trace element fertilizer rate reduced by 20%. The total irrigation water volume and fertilization frequency remained unchanged.

[0080] 14) Nanobubble hydrogen water irrigation. During irrigation, the outlet hydrogen concentration of the hydrogen-rich water was approximately 1200 ppb. The conventional fertilization schedule in Table 1 was adjusted, with the compound fertilizer rate remaining unchanged and the trace element fertilizer rate reduced by 20%. The total irrigation water volume and fertilization frequency remained unchanged.

[0081] 15) Nanobubble hydrogen water irrigation. During irrigation, the outlet hydrogen concentration of the hydrogen-rich water was approximately 1500 ppb. The conventional fertilization schedule in Table 1 was adjusted, with the compound fertilizer rate remaining unchanged and the trace element fertilizer rate reduced by 20%. The total irrigation water volume and fertilization frequency remained unchanged.

[0082] 16) Conventional water irrigation. Adjust the conventional fertilization plan in Table 1, maintaining the same application rate of compound fertilizer and reducing the application rate of trace element fertilizer by 50%. The total amount of irrigation water and the number of fertilization applications remain unchanged.

[0083] 17) Nanobubble hydrogen water irrigation. During irrigation, the hydrogen concentration of the hydrogen-rich water outlet was approximately 300 ppb. The conventional fertilization schedule in Table 1 was adjusted, with the compound fertilizer rate remaining unchanged and the trace element fertilizer rate reduced by 50%. The total irrigation water volume and fertilization frequency remained unchanged.

[0084] 18) Nanobubble hydrogen water irrigation. During irrigation, the hydrogen concentration of the hydrogen-rich water outlet was approximately 500 ppb. The conventional fertilization schedule in Table 1 was adjusted, with the compound fertilizer rate remaining unchanged and the trace element fertilizer rate reduced by 50%. The total irrigation water volume and fertilization frequency remained unchanged.

[0085] 19) Nanobubble hydrogen water irrigation. During irrigation, the outlet hydrogen concentration of the hydrogen-rich water was approximately 1200 ppb. The conventional fertilization schedule in Table 1 was adjusted, with the compound fertilizer rate remaining unchanged and the trace element fertilizer rate reduced by 50%. The total irrigation water volume and fertilization frequency remained unchanged.

[0086] 20) Nanobubble hydrogen water irrigation. During irrigation, the outlet hydrogen concentration of the hydrogen-rich water was approximately 1500 ppb. The conventional fertilization schedule in Table 1 was adjusted, with the compound fertilizer rate remaining unchanged and the trace element fertilizer rate reduced by 50%. The total irrigation water volume and fertilization frequency remained unchanged.

[0087] Ripe blueberries were picked, and 200 blueberry samples were randomly selected from each group to measure the single blueberry weight.

[0088] Thirty blueberry samples were randomly selected from each group, ground into powder by adding liquid nitrogen, and the contents of some mineral elements were determined by inductively coupled plasma optical emission spectrometry (ICP-OES).

[0089] Table 2 shows the effects of changes in the composition of the fertigation compositions in groups 1 to 20 on the weight of blueberry fruit and the content of mineral elements (iron, copper, magnesium, zinc and boron).

[0090] The results from Groups 1 to 5 show that, without the application of trace element fertilizer, when the outlet hydrogen concentration of hydrogen-rich water was 300 ppb (Group 2) and 1500 ppb (Group 5), the blueberry weight and the contents of magnesium, copper, iron, zinc, and boron ions remained almost the same as in Group 1, showing no significant increase. This may be due to the less pronounced biological effects of low-concentration hydrogen water. However, at high concentrations, it is hypothesized that the biological effects of hydrogen as a signaling molecule reach a certain steady-state equilibrium. At outlet hydrogen concentrations of 500 ppb (Group 3) and 1200 ppb (Group 4), blueberry weight and the contents of magnesium, copper, iron, zinc, and boron ions significantly increased compared to Group 1. The effect in Group 4 was even better than that in Group 3.

[0091] Under the conventional fertilization regimen outlined in Table 1, blueberry weight and magnesium, copper, iron, zinc, and boron ion contents in blueberries grown with hydrogen-rich water outlet concentrations of 300 ppb (Group 7) and 1500 ppb (Group 10) remained nearly identical to those in Group 6, showing no significant improvement. However, blueberry weight and magnesium, copper, iron, zinc, and boron ion contents significantly increased in blueberries grown with hydrogen-rich water outlet concentrations of 500 ppb (Group 8) and 1200 ppb (Group 9), compared to Group 6. Group 9 achieved the best results.

[0092] When the conventional fertilization schedule in Table 1 was adjusted, maintaining the same compound fertilizer rate and reducing the trace element fertilizer rate by 20%, blueberry fruit weight and magnesium, copper, iron, zinc, and boron ion contents in the hydrogen-rich water at outlet concentrations of 300 ppb (Group 12) and 1500 ppb (Group 15) were nearly identical to those in Group 11. At an outlet hydrogen concentration of 500 ppb (Group 13), blueberry fruit weight and magnesium, copper, iron, zinc, and boron ion contents approached those in Group 6. In other words, the biological effects of hydrogen-rich water at this level were nearly equivalent to those of a 20% trace element fertilizer. Hydrogen-rich water has a complementary effect on the reduction in trace element fertilizer rates. At an outlet hydrogen concentration of 1200 ppb (Group 14), blueberry fruit weight and magnesium, copper, iron, zinc, and boron ion contents were higher than those in Group 6.

[0093] When the conventional fertilization schedule in Table 1 was adjusted, maintaining the same compound fertilizer rate and reducing the trace element fertilizer rate by 50%, blueberry fruit weight and magnesium, copper, iron, zinc, and boron ion contents in the 300 ppb (Group 17) and 1500 ppb (Group 20) hydrogen-rich water outlet concentrations remained nearly the same as in Group 16. When the hydrogen-rich water outlet concentration was 500 ppb (Group 18), blueberry fruit weight and magnesium, copper, iron, zinc, and boron ion contents significantly increased compared to Group 16. When the hydrogen-rich water outlet concentration was 1200 ppb (Group 19), blueberry fruit weight and magnesium, copper, iron, zinc, and boron ion contents approached those in Group 6. In other words, the biological effects of hydrogen-rich water at this level were nearly equivalent to those of a 50% trace element fertilizer.

[0094] Table 2 Single fruit weight and mineral element content of blueberry

[0095] Group No. Hydrogen concentration of hydrogen-rich water outlet (ppb) Trace element fertilizer (%) Single fruit weight (g) / Change compared with treatment No. 6 (%) Iron (μg / g) / Change compared with treatment No. 6 (%) Copper (μg / g) / Change compared with treatment No. 6 (%) Magnesium (μg / g) / Change compared with treatment No. 6 (%) Zinc (μg / g) / Change compared with treatment No. 6 (%) Boron (μg / g) / Changes compared with treatment 6 (%) 100 1.71±0.10 / -15.76 36.83±9.78 / -44.7 2 3.47±0.01 / -22.54 2 12.40±4.12 / -18.98 4.28±0.15 / -15.91 14.15±1.28 / -7.15 2 3000 1.70±0.12 / -16.26 37.20±10.08 / -41.13 3.46±0.02 / -22.77 2 12.52±2.25 / -18.94 4.33±0.21 / -14.93 14.45±2.47 / -5.18 350001.75±0.21 / -13.7941.25±12.51 / -34.723.68±0.06 / -17.86220.46±7.68 / -15.914.45±0.36 / -12.5714.37±1.59 / -5.714120001.80±0.36 / -11.3346.37±13.25 / -26.623.82±0.05 / -14.73228.20±8.67 / -12.964.66±0.17 / -8.4514.34±1.72 / -5.915150001. 68±0.27 / -17.2436.03±10.78 / -42.983.38±0.11 / -24.55210.06±6.53 / -19.884.42±0.26 / -13.1614.15±2.64 / -7.15601002.03±0.67 / ---63.19±13.51 / ---4.48±0.03 / ---262.17±6.94 / ---5.09±0.22 / ---15.24±0.58 / ---73001002.02±0.33 / -0.4963.20±10.0 2 / 0.014.49±0.02 / 0.22262.26±7.02 / 0.035.18±0.67 / 1.7715.35±1.66 / 0.7285001002.15±0.59 / 5.9180.23±12.31 / 26.974.74±0.04 / 5.8280.26±7.24 / 6.95.48±0.45 / 7.6615.93±0.92 / 4.53912001002.32±0.78 / 14.2995.87±4.14 / 51.724.94±0.01 / 10.27294.87±13.03 / 12.475.66±0.24 / 11.2016.14±2.68 / 5.911015001002.00±0.24 / -1.4863.16±11.13 / -0.054.48±0.06 / 0262.00±5.88 / -0.065.12±0.16 / 0.5915.41±1.85 / 1.12110801.92±0.35 / -5.4256.86±14.62 / -10.024.20±0.08 / -6.25250.53±4.86 / -4.444.84±0.56 / -4.9114.82±1.22 / -2.7612300801.93±0.80 / -4.9356.90±10.23 / -9.954.21±0.10 / -6.07251.02±4.38 / -4.255.01±0.21 / -1.5715.03±1.45 / -1.3813500802.00±0.12 / -1.4862.59±10.25 / -0.954.50±0.12 / 0.45263.15±5.62 / 0.375.04±0.36 / -0.9815.25±1.98 / 0.07141200802.20±0.63 / 8.3977.52±11.26 / 22.684.69±0.08 / 4.69278.35±7.24 / 6.175.4±0.42 / 6.0915.36±2.54 / 0.79151500801.90±0.75 / -6.456.75±13.51 / -10.194.18±0.03 / -6.7250.23±6.94 / -4.555.05±0.31 / -0.7914.87±3.21 / -2.43160501.85±0.52 / -8.8750.86±12.68 / -19.514.08±0.07 / -8.93239.08±6.85 / -8.814.63±0.35 / -9.0414.44±1.65 / -5.2517300501.86±0.21 / -8.3750.90±12.05 / -19.454.08±0.02 / -8.93239.12±6.85 / -8.924.66±0.66 / -8.4514.74±1.54 / -3.2818500501.95±0.83 / -3.9456.80±9.62 / -10.114.29±0.12 / -4.24250.65±10.56 / -4.394.83±0.43 / -5.1114.82±2.01 / -2.76191200502.04±0.22 / 0.4963.21±10.53 / 1.584.49±0.04 / 0.22262.30±5.62 / 0.035.09±0.24 / 014.95±2.28 / -1.90201500501.87±0.12 / -9.2651.27±12.68 / -18.864.11±0.11 / -8.26243.25±8.32 / -7.224.75±0.25 / -6.6814.77±1.81 / -3.08.

[0096] From the above results, it can be seen that when the outlet hydrogen concentration of hydrogen-rich water is in the range of 0 to 300 ppb, the fertigation composition does not significantly improve the single fruit weight and mineral element content of blueberries compared with the conventional fertilization scheme. When the outlet hydrogen concentration of hydrogen-rich water is in the range of 500 to 1200 ppb, the fertigation composition has a significant promoting effect on the single fruit weight and mineral element content of blueberries, especially the five elements of iron, copper, magnesium, zinc, and boron. When the outlet hydrogen concentration of hydrogen-rich water continues to rise to close to 1500 ppb, the effect of the fertigation composition on the single fruit weight and mineral element content of blueberries is not better, and is even similar to the result of ordinary water irrigation. This is unexpected. Not all concentrations of hydrogen-rich water can achieve the desired positive promoting effect on the single fruit weight and mineral elements of blueberries. In the fertigation composition, the higher the content of hydrogen-rich water, the better.

[0097] The patterns and conclusions observed by the inventors suggest that applying the fertigation composition can increase blueberry yield and mineral content while reducing the amount of trace element fertilizer required. The appropriate concentration of hydrogen-rich water promotes plant absorption of mineral elements from the soil, increasing the mineral content of blueberry fruit and improving the nutritional quality of the berries.

[0098] Previous research has focused on the role of hydrogen or hydrogen water as a growth regulator for crops. It's generally believed that irrigation with hydrogen water can positively regulate crop growth, development, and nutritional quality. However, the inventors have observed that only irrigation with hydrogen water within a specific concentration range significantly improves blueberry fruit weight and mineral content. Otherwise, either the hydrogen water is insufficient to exert its biological effects, or the biological effects are not enhanced with higher hydrogen water concentrations, resulting in unnecessary hydrogen waste. Example

[0099] Hydrogen-rich water is slightly alkaline, with a pH typically between 7.0 and 9.5. Blueberries prefer to grow in acidic (pH 4.0 to 5.5) sandy soils with high organic matter content, good soil aeration, and ample water.

[0100] The following examples were designed to observe the effects of applying a fertigation composition containing hydrogen-rich water on soil pH and blueberry growth.

[0101] The blueberry soil is treated as follows:

[0102] Group A: Sulfur powder 0.22 kg / m 2 The soil pH was adjusted to approximately 4.5. Ordinary water was used for irrigation. The fertilization schedule followed the conventional fertilization schedule in Table 1.

[0103] Group B: Irrigated with nanobubble hydrogen water. During irrigation, the outlet hydrogen concentration of the hydrogen-rich water was approximately 1200 ppb. Fertilization followed the conventional fertilization schedule in Table 1.

[0104] Soil samples were collected in June and the pH value of the soil was measured.

[0105] Ripe blueberries were picked and 200 samples were randomly selected from each group. The weight of each blueberry was measured. Additionally, 30 blueberry samples were randomly selected from each group and ground into powder using liquid nitrogen. The contents of selected mineral elements were then determined using inductively coupled plasma optical emission spectrometry (ICP-OES). The results are shown in Table 3.

[0106] As shown in Table 3, while maintaining a stable soil pH, a fertigation composition containing a certain concentration of hydrogen-rich water can achieve a soil improvement effect similar to that achieved with additional sulfur powder. Furthermore, it can maintain or even increase blueberry fruit weight and the content of some mineral elements. This is surprising, as the alkalinity of hydrogen-rich water at an appropriate concentration does not adversely affect blueberries.

[0107] Table 3 Blueberry soil pH, fruit weight and mineral element content

[0108] Group No. AB Sulfur dosage (kg / m2) 0.220 Hydrogen concentration of hydrogen-rich water outlet (ppb) 01200 Trace element fertilizer (%) 100100 Soil pH value 4.5±0.564.9±0.85 Single fruit weight (g) / Change compared with Group A treatment (%) 2.00±0.67 / ---2.28±0.53 / 14.00 Iron (μg / g) / Change compared with Group A treatment (%) 61.56±10.23 / ---91.05±3.26 / 47.9 Copper (μg / g) / Change compared with Group A treatment (%) Treatment change (%) 4.32±0.05 / ---4.76±0.02 / 10.19 Magnesium (μg / g) / Compared with group A Treatment change (%) 256.35±5.24 / ---282.19±10.34 / 10.08 Zinc (μg / g) / Compared with group A Treatment change (%) 5.04±0.23 / ---5.76±0.21 / 14.29 Boron (μg / g) / Compared with group A Treatment change (%) 14.08±0.56 / ---15.23±0.69 / 8.17

[0109] In summary, the inventors unexpectedly discovered that by combining hydrogen-rich water technology with integrated water-fertilizer technology, they have developed a fertigation composition and application method suitable for blueberries. This fertigation composition helps alleviate the problems of soil fertility loss and nutrient loss caused by the continued use of traditional fertilizers.

[0110] The present invention is described in this specification as a preferred embodiment. The above embodiments are intended to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning, or limited experimentation based on the concept of the present invention should be within the scope of the present invention.

Claims

1. A fertigation composition for maintaining or increasing the mineral element content of crops, characterized in that The fertigation composition comprises hydrogen-rich water, compound fertilizer, and trace element fertilizer, wherein the trace element fertilizer comprises one or more of boron, calcium, magnesium, iron, zinc, copper, manganese, and molybdenum. During the period of applying the fertigation composition, the outlet hydrogen concentration of the hydrogen-rich water is maintained within the range of 300 to 1200 ppb.

2. The fertigation composition according to claim 1, wherein Maintain the outlet hydrogen concentration of hydrogen-rich water within the range of 500~1200ppb.

3. The fertigation composition according to any one of claims 1 to 2, characterized in that In the fertigation composition, whenever the first predetermined amount of trace element fertilizer is reduced, the outlet hydrogen concentration of the hydrogen-rich water needs to be increased to a second predetermined amount.

4. The fertigation composition according to claim 3, wherein The second predetermined amount increases as the first predetermined amount increases.

5. The fertigation composition according to claim 3, wherein The increase of the first predetermined amount is in a linear relationship with the increase of the second predetermined amount.

6. The fertigation composition according to claim 5, wherein When the first predetermined amount is 20% to 50%, the second predetermined amount is 500 ppb to 1200 ppb.

7. The fertigation composition according to any one of claims 1 to 2, characterized in that The pH value of the fertigation composition is 4.0 to 5.

0.

8. The fertigation composition according to any one of claims 1 to 2, characterized in that The compound fertilizer includes at least one or more of nitrogen, phosphorus or potassium.

9. The fertigation composition according to claim 8, wherein The nitrogen element comes from ammonium nitrate and / or ammonium sulfate.

10. The fertigation composition according to claim 8, wherein The phosphorus element comes from monoammonium phosphate and / or diammonium phosphate.

11. The fertigation composition according to claim 8, wherein The potassium element comes from potassium sulfate, potassium dihydrogen phosphate and / or potassium fulvic acid.

12. The fertigation composition according to any one of claims 1 to 2, characterized in that In the trace element fertilizer, the boron element contained is derived from boric acid and / or borax, and / or the calcium element contained is derived from calcium sulfate, calcium carbonate and / or chelated calcium, and / or the magnesium element contained is derived from magnesium sulfate and / or EDTA chelated magnesium, and / or the iron element contained is derived from ferrous sulfate and / or EDTA chelated iron, and / or the zinc element contained is derived from zinc sulfate and / or EDTA chelated zinc, and / or the copper element contained is derived from copper sulfate and / or EDTA chelated copper, and / or the manganese element contained is derived from manganese sulfate and / or EDTA chelated manganese, and / or the molybdenum element contained is derived from ammonium molybdate.

13. A method of applying the fertigation composition according to any one of claims 1 to 12, characterized in that: From February to April, the fertigation composition was applied at a rate of 95-200 mg / L NH4 + 3800~7750 mg / L NO3 - 500~1050 mg / L PO4 3- , 800~1600 mg / L K + , 500~1000 mg / L of Ca 2+ , 400~830 mg / L SO4 2- , 100~200 mg / L Fe 3+ 12.5~25 mg / L Mg 2+ , 0.65~1.3 mg / L of Mn 2+ , 0.15~0.3 mg / L Zn 2+ , 0.01~0.02 mg / L Cu 2+ and 0.015~0.03 mg / L MoO4 2- ; From May to June, the fertigation composition was applied at a rate of 1800-3600 mg / L of NH4 + , 900~1800 mg / L NO3 - , 1000~2000 mg / L K + , 18~36 mg / L Ca2 + 10~20 mg / L BO3 3- , 10~20 mg / L SO4 2- , 0.6~1.2 mg / L Fe 3+ 135~270 mg / L Mg 2+ , 15~30 mg / L Mn 2+ , 18~36 mg / L Zn 2+ , 5~10 mg / L Cu 2+ and 7.5~15 mg / L MoO4 2- .

14. The administration method according to claim 13, wherein From February to April, the ratio of the outlet hydrogen concentration of the hydrogen-rich water to the application amount of the fertigation composition is greater than 15.8 ppb / g, preferably greater than 37.9 ppb / g.

15. The administration method according to claim 13, wherein From February to April, the fertigation composition was applied at a rate of 0.5 to 2.5 liters per plant, 1 to 2 times a day.

16. The administration method according to claim 13, wherein From May to June, the ratio of the outlet hydrogen concentration of the hydrogen-rich water to the amount of fertigation composition applied is greater than 18.3 ppb / g, preferably greater than 44.0 ppb / g.

17. The administration method according to claim 13, wherein From May to June, the fertigation composition was applied at a rate of 2.5 to 3.5 liters per plant, 2 to 3 times a day.