WO2020059858A1 - Hydroculture cultivation agent and hydroculture method using hydroculture cultivation agent - Google Patents

Abstract

[Problem] The present invention addresses the problem of providing a hydroculture cultivation agent that can improve crop yield and crop quality, and can also maintain the cultivation environment for a greater diversity of crops in a hydroculture method, without using different nutrient solutions. [Solution] A hydroculture cultivation agent according to the present invention is characterized by a cellulose nanofiber dispersion or by containing cellulose nanofibers and a fertilizer component containing at least one of nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, manganese, boron, zinc, molybdenum, copper, chlorine, and nickel.

Description

A hydroponic cultivation agent and a hydroponic cultivation method using the hydroponic cultivation agent.

INDUSTRIAL APPLICABILITY The present invention can increase the yield by using cellulose nanofibers together with fertilizer components in nutrient cultivation, and can suppress the growth of bacteria during cultivation, prevent decay, off-flavor, etc., and cultivate. The present invention relates to a hydroponic cultivation agent capable of maintaining an environment and a hydroponic cultivation method using the hydroponic cultivation agent.

Conventionally, issues in agricultural production include promoting plant growth and increasing the yield per unit area, improving production efficiency and increasing the overall yield, plants that are resistant to pathogenic bacteria, pests, or climate change. And the like.
In order to increase the yield, it is necessary to prepare a fertilizer, shorten the cultivation period, and increase the plant cultivation efficiency and turnover. Also, the shorter the cultivation period, the less the possibility of damage by pathogenic bacteria and pests. Shortening the cultivation period of a plant in this way involves a growth promoting effect, and it is an issue how to improve the conventional cultivation method to promote the growth or cultivate a high quality crop. I have.

On the other hand, cellulose nanofibers (hereinafter, also referred to as CNFs) are attracting attention as carbon-neutral materials for the purpose of efficiently reducing atmospheric CO2 as a measure against global warming. Generally, CNF is considered to be a fibrous substance made of cellulose having a diameter of 3 to 100 nm and an aspect ratio (fiber length / fiber width) of 100 or more. CNF has excellent properties such as light weight, high strength, and low coefficient of thermal expansion, and is expected to be used in various fields in the future.

複合 Generally, as a fertilizer, a compound fertilizer is used in which a plurality of components including nitrogen, phosphorus, and potassium are mixed in a well-balanced manner in order to supplement components necessary for the growth of plants such as crops and flowers. As a form of the compound fertilizer, there are a solid fertilizer using the fertilizer as a solid and a liquid fertilizer using the fertilizer as an aqueous solution. When the fertilizer is applied as a solid fertilizer, there is a possibility that an excess or deficiency of the component may occur, or a difference in the concentration of the component may occur in the soil, which may result in a decrease in crop yield. In this regard, (1) when fertilizing as a liquid fertilizer (hereinafter sometimes referred to as liquid fertilizer), by accurately preparing the components, it is possible to reduce the risk of causing an excess or deficiency of the components or a difference in the concentration of the components in the soil. can do.

液体 Liquid fertilizers having these advantages are widely used in hydroponics for managing fertilization of plants. For the liquid fertilizer, the optimal component, component concentration, pH, temperature, etc. are selected according to the cultivated crop. At this time, the following inventions are disclosed as components selected for improving the yield and the quality of the crop.

Patent Document 1 discloses an invention of a method for increasing the yield of a plant, which comprises contacting a plant with cyclopropene applied multiple times.

特許 Further, Patent Document 2 discloses an invention of a method for cultivating a plant that supplies a nutrient solution containing 1 to 500 ppm of petaine in the cultivation of a plant that supplies a nutrient solution to a plant supported on a base bed.

Furthermore, Patent Document 3 discloses an invention relating to a composition containing tetra-N-acyl-beta-D-methyl-glucoside (TAMG), which is a synthetic LCO compound, and a related compound thereof.

Methods by multiple applications of cyclopropene described in Patent Documents 1-3, nutrient solution containing 1-500 ppm of petaine, and tetra-N-acyl-beta-D-methyl-glucoside (TAMG) The composition containing and its related compounds is an invention which can be useful for the growth promoting action of a specific plant. However, there is still a need for an effective cultivation agent that can improve the yield and quality of crops without using nutrient solutions for more various crops.

JP-T-2016-511762 JP-A 1-228416 JP-T-2016-511775

The present invention has been made in view of the above circumstances, and is to provide a cultivating agent in hydroponic cultivation. More specifically, the present invention can promote plant growth and improve crop yield and quality. It is an object to provide a cultivation agent for hydroponic cultivation and a hydroponic cultivation method.

Further, another object of the present invention is to provide a cultivation agent for hydroponics that is excellent in maintaining a cultivation environment.

As a result of intensive studies to achieve the above object, the present inventor focused on the vast specific surface area of the cellulose nanofiber and the surface adsorption force resulting therefrom. That is, this is mixed with a liquid fertilizer, and fertilizer is applied in a state where components necessary for plant growth in the liquid fertilizer are adsorbed to the cellulose nanofiber, or a cellulose nanofiber dispersion is sprayed in the presence of the fertilizer component, The present inventors have found that the above problem can be solved by adsorbing the fertilizer component on cellulose nanofibers, and have completed the present invention.

That is, the cultivation agent for hydroponics of the present invention is characterized by containing cellulose nanofibers.

According to the present invention, there are provided a cultivation agent and a cultivation method capable of promoting the growth of plants and improving the yield and quality of crops. Further, a cultivation agent for hydroponics which is excellent in maintaining the cultivation environment is provided.

It is a conceptual diagram of a manufacturing (defibrating process) apparatus of CNF. It is a conceptual diagram of another manufacturing (defibrating) apparatus of CNF. It is a conceptual diagram which expands and shows a part of manufacturing (defibrating process) apparatus of CNF in FIG. 4 is a photograph showing the result of cultivating Casablanca of Example 1. 5 is a photograph showing the result of cultivating Casablanca of Comparative Example 1. It is a figure showing the result of transition of the amount of tomato harvest of Example 2 and Comparative Example 2. It is a photograph which shows the result of the root after harvest of the tomato of Example 2 and Comparative Example 2. It is a photograph which shows the result of cultivating radish for 20 days of Example 3 and Comparative Example 3. 9 is a photograph showing a radish portion of the radish of Example 3. 9 is a photograph showing a radish portion of 20 days radish of Comparative Example 3. It is a photograph which shows the result of cultivating the bean seedlings of Example 5 and Comparative Example 5. It is a photograph which shows the result of cultivating the broccoli sprout of Example 5 and Comparative Example 5. It is a figure showing a bacteria measurement result. 14 is a photograph showing a result of the cabbage cultivation of Example 7 at an early stage. 9 is a photograph showing a result of an initial stage of cabbage cultivation of Comparative Example 7. 9 is a photograph showing the results of Example 8 and Comparative Example 8 in the initial stage of broccoli cultivation.

Next, the cultivation agent for hydroponics according to one embodiment of the present invention will be described, but the present invention is not limited to this embodiment.

The cultivation agent for hydroponics according to one embodiment of the present invention is obtained by mixing a CNF dispersion with a liquid fertilizer.

First, a method for preparing a CNF dispersion will be described. In the present invention, examples of CNF include CNF derived from polysaccharides including natural plants such as wood fiber, hardwood, conifer, bamboo fiber, sugarcane fiber, seed hair fiber, leaf fiber, and seaweed. Further, it may be produced from crop residues derived from plant leaves, flowers, stems, roots, hulls, and the like, such as bagasse, rice straw, tea husks, and fruit juice pomace. These CNFs may be used alone or in combination of two or more. As the polysaccharide, pulp having an α-cellulose content of 60% to 99% by mass is preferably used as a raw material. If the α-cellulose content is 60% by mass or more, the fiber diameter and the fiber length can be easily adjusted, and the entanglement of the fibers can be suppressed, so that the sprayability is good, and the plant rots to increase the plant growth. The growth environment can be maintained without hindrance. When an α-cellulose content of less than 60% by mass is used, the properties of natural cellulose crystals cannot be sufficiently brought out, and there is a possibility of causing deterioration over time due to decay or the like during storage, while 99% by mass. In the case of using the above, it is difficult to defibrate the fiber to the nano level.

As the pulp, pulp for papermaking can be used because it is easily available and inexpensive, and the production method is not particularly limited.For example, bleached kraft pulp, unbleached kraft pulp, sulfite pulp, soda pulp, thermomechanical pulp, Pulp such as deinked pulp, waste paper pulp, and dissolved pulp may be used. Among these, bleached kraft pulp and unbleached kraft pulp are preferable because they are more easily available.

The crystallinity of CNF is preferably 50 or more. The degree of crystallinity can be measured by an X-ray diffraction method or the like. If the degree of crystallinity is less than 50, it is not possible to sufficiently bring out the properties possessed by natural crystals of cellulose. May cause.

The CNF in the present invention can be obtained as a CNF dispersion (hereinafter, sometimes referred to as a hydrous CNF) by performing the following defibration treatment.
The defibration process is performed using the underwater facing collision method (hereinafter, also referred to as ACC method) shown in FIG. In this method, pulp suspended in water is introduced into two opposing nozzles (108a, 108b in FIG. 1: 107) in a chamber (FIG. 1: 107), and injected and collided from these nozzles toward one point. is there. The apparatus shown in FIG. 1 is of a liquid circulation type, and includes a tank (FIG. 1: 109), a plunger (FIG. 1: 110), two opposing nozzles (FIG. 1: 108a, 108b), and heat if necessary. An exchanger (FIG. 1: 111) is provided, and fine particles dispersed in water are introduced into two nozzles, and are jetted from the nozzles (FIGS. 1: 108a, 108b) that match each other under high pressure and collide with each other in water.

前 Before performing the defibration process, the defibration process may be performed using a pretreatment device (FIGS. 2 and 3). As another defibrating method, such a pretreatment device may be used. The defibration treatment using the pretreatment device is performed by causing high-pressure water of about 50 to 400 MPa to collide with a polysaccharide made into a water mixture of 0.5 to 10% by mass. This can be performed, for example, using the manufacturing apparatus 1 shown in FIG. The production apparatus 1 includes a polysaccharide slurry supply path 3, which is a first liquid medium supply path, which is arranged so as to supply a polysaccharide slurry to one chamber 2, and a non-polysaccharide slurry, for example, water, in one chamber. And a second liquid medium supply path 4 circulating through the second liquid medium supply path 4. In one chamber 2, there is provided an orifice injection section 5 for orifice-injecting the non-polysaccharide slurry of the second liquid medium supply path 4 in a direction intersecting with the polysaccharide slurry supply direction from the polysaccharide slurry supply path 3. The polysaccharide slurry supply path 3 allows the polysaccharide slurry to circulate through one chamber 2.

The polysaccharide slurry supply path 3 and the second liquid medium supply path 4 have an intersection 6 in one chamber 2.
The polysaccharide slurry supply path 3 is a polysaccharide slurry supply part, in which a tank 7 for storing the polysaccharide slurry and a pump 8 are arranged in a circulation path 9, while the second liquid medium supply path 4 is a tank 10, a pump 11, The exchanger 12 and the plunger 13 are arranged in the liquid medium supply path 4 which is a circulation path.

The non-polysaccharide slurry is, for example, water, and is initially stored in the tank 10, and then the nano-micronized polysaccharide stored in the tank 10 after passing through the intersection 6 with the operation of the cellulose nanofiber manufacturing apparatus 1. Those that are to be included at a concentration corresponding to the degree of operation are also generically referred to.

As shown in FIG. 3, the circulation path 9 of the polysaccharide slurry supply path 3 is arranged so as to penetrate the chamber 2, and the non-polysaccharide slurry is orifice-injected in a direction intersecting with the circulation path 9 so that the circulation path 9 can be penetrated. Then, the orifice injection port 14 of the orifice injection section 5 connected to the plunger 13 of the second liquid medium supply path 4 opens inside the chamber 2. A discharge port 15 of the chamber 2 is provided at a position opposite to the orifice injection port 14 of the chamber 2, and a circulation path of the second liquid medium supply path 4 is connected to the discharge port 15 of the chamber 2 to form a second liquid medium. The medium supply path 4 is configured.

On the other hand, the circulation path 9 of the polysaccharide slurry supply path 3 is formed by using, for example, a vinyl hose, a rubber hose, an aluminum pipe, or the like. A directional valve 16 is mounted. Further, a one-way valve 17 that is opened only in the discharge direction from the chamber 2 is attached to the circulation path 9 on the exit side from the chamber 2. In addition, an air intake valve 18 is attached to the circulation path 9 between the chamber 2 and the one-way valve 17, and the air intake valve 18 is opened only in a direction in which air is sucked into the circulation path 9 from the outside.

According to the above-described apparatus for producing cellulose nanofibers, cellulose nanofibers are produced as follows.
The non-polysaccharide slurry is circulated through the second liquid medium supply path 4 through the chamber 2. Specifically, the non-polysaccharide slurry in the tank 10 is passed through the heat exchanger 12 and the plunger 13 using the pump 11 and circulated in the liquid medium supply path 4. On the other hand, the polysaccharide slurry is circulated in the polysaccharide slurry supply path 3 through the chamber 2. Specifically, the polysaccharide slurry in the tank 7 is circulated in the circulation path 9 formed by using a vinyl hose, a rubber hose, or the like using the pump 8.

Thus, the non-polysaccharide slurry circulating in the second liquid medium supply path 4 is orifice-injected to the polysaccharide slurry circulating in the polysaccharide slurry supply path 3 and flowing in the chamber 2. Specifically, high-pressure water is supplied from the plunger 13 to the orifice injection port 14 connected to the plunger 13, and the orifice is injected from the orifice injection port 14 toward the circulation path 9 at a high pressure of about 50 to 400 MPa.

As a result, it passes through the through holes 26a and 26b formed in advance in the circulation path 9 formed using, for example, a vinyl hose, a rubber hose, or an aluminum pipe, and passes through the inside of the circulation path 9 in a direction crossing the circulation path 9. The resulting non-polysaccharide slurry is discharged toward the outlet 15 of the chamber 2 while entraining the polysaccharide slurry circulating in the circulation path 9 and flows into the second liquid medium supply path 4. Thereby, the non-polysaccharide slurry circulates again in the second liquid medium supply path 4.
In the course of repeating the above process, the polysaccharide in the polysaccharide slurry circulating in the polysaccharide slurry supply path 3 and flowing in the chamber 2 and the polysaccharide in the non-polysaccharide slurry circulating in the second liquid medium supply path 4 are gradually defibrated. Thus, a CNF dispersion having a high degree of uniformity of fibrillation according to the intended use can be obtained.

The degree of defibration from pulp fibers to CNF can be evaluated by the viscosity value of the CNF dispersion. That is, the CNF contained in the CNF dispersion having an increased degree of fibrillation has a short fiber length, and thus has a low viscosity value. Therefore, a CNF dispersion having a high degree of fibrillation has a low viscosity. On the other hand, the CNF dispersion having a higher viscosity value has a higher viscosity value because the CNF contained in the CNF dispersion has a longer fiber length. Therefore, the degree of defibration is lower than that of the CNF dispersion.
Further, since the ratio (aspect ratio) of the fiber length to the fiber diameter after defibration is different for each pulp fiber, the viscosity value of the CNF dispersion is different.
Further, for example, by combining different kinds of pulp fibers or adjusting the degree of defibration, the viscosity of the CNF aqueous dispersion at 1 wt% can be adjusted within a range of about 300 to 10,000 mPa · s.

ＣＮ The CNF obtained as described above has a structural formula represented by the following chemical formula 1 because there is no change in the structure of the cellulose molecule because nano-refining is performed by cleaving only the interaction between natural cellulose fibers. In other words, CNF used in the present invention has six hydroxyl groups in the cellobiose unit in Chemical Formula 1 and means that it is not chemically modified. This can be confirmed by comparing the IR spectrum of cellulose with CNF used in the present invention using FT-IR.に よ り According to the ACC method, the average particle length of the cellulose fibers can be pulverized to 10 μm, and as a result, CNF having an average thickness of 3 to 200 nm and an average length of 0.1 μm or more can be obtained. The average thickness and average fiber length are measured by appropriately selecting a scanning electron microscope (SEM), a transmission electron microscope (TEM), etc., observing and measuring CNF, and selecting at least 20 from the obtained photographs. , By averaging them. On the other hand, in the facing collision treatment, the applied energy is far less than the energy for breaking the covalent bond (estimated 1/300 or less), and the polymerization degree of cellulose is hardly reduced. The cellulose nanofiber obtained by the present ACC method has a hydrophilic site and a hydrophobic site, and exhibits amphiphilicity.

By defibrating CNF to an average thickness of 3 to 200 nm, it has fluidity and excellent sprayability. On the other hand, when the average thickness is less than 3 nm, there is a possibility that it is difficult to increase the solid content concentration due to poor dehydration, and when the average thickness is more than 200 nm, the fluidity is reduced and the sprayability is good. In addition, the distribution of the fiber thickness becomes wide, and there is a possibility that the fiber does not show a homogeneous property.

The CNF used in the present invention preferably has an average degree of polymerization in the range of 500 to 900. The average degree of polymerization can be measured by a measuring method using a copper ethylenediamine solution or the like.
0.15 g of the CNF solid content was dissolved in 30 mL of a 0.5 M copper ethylenediamine solution, and the viscosity η of the CNF / copper ethylenediamine solution was measured using a Cannon-Fenske kinematic viscosity tube to determine the viscosity of the 0.5 M copper ethylenediamine solution. As η0, the intrinsic viscosity [η] was determined from the following Schulz-Brushke equation, and the polymerization degree DP was calculated from the following Mark-Houwink-Sakurada equation.
Specific viscosity ηsp = η / η0-1
Intrinsic viscosity [η] = ηsp / {c (1 + A × ηsp)}
η0 is the viscosity of the 0.5 M copper ethylenediamine solution, c is the CNF concentration (g / mL), A is a characteristic value determined by the type of the solution, and A = 0. 28.
Degree of polymerization DP = [η] / Ka
K and a are intrinsic values determined by the types of the polymer and the solvent, and K = 0.57 and a = 1 in the case of cellulose dissolved in a copper ethylenediamine solution.

In the present invention, TEMPO oxidation catalyst treatment, phosphoric acid esterification treatment, ozone treatment, enzyme treatment, maleic acid treatment, hydrophobic modification with alkenyl succinic anhydride, alkyl ketene, which are known as other methods for producing cellulose nanofibers, Wet pulverization using mechanical action such as cellulose nanofiber or grinder (stone mill type pulverizer), disk type refiner, conical refiner etc. obtained by chemical treatment such as hydrophobic modification by dimer, hydrophobic modification by acetylation. Cellulose nanofibers obtained by a physical method of thinning cellulosic fibers can be used as a CNF dispersion in the present invention. Cellulose nanofibers obtained by a method combining chemical treatment and physical treatment can also be used as a CNF dispersion.

-Cultivating agent for hydroponics-
The cultivation agent for hydroponics of the present invention refers to a composition comprising a fertilizer component and a CNF dispersion or a CNF dispersion. Here, the form of the fertilizer component is not particularly limited, and may be a liquid or a solid (solid).
The fertilizer component in the present invention may contain at least one of nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, manganese, boron, zinc, molybdenum, copper, chlorine, and nickel. In addition, the liquid fertilizer or the solid (solid) fertilizer may contain other components as long as the various functions of the fertilizer component are not impaired.

Further, a commercially available liquid fertilizer may be used as the liquid fertilizer. Specific examples of commercially available liquid fertilizers include urea compound liquid fertilizer, urea compound liquid fertilizer containing boron, manganese and magnesia, nitrate compound liquid fertilizer, nitrate-lime liquid fertilizer, organic liquid fertilizer, phosphorus ammonium liquid fertilizer, powder liquid fertilizer, nitrogen-free liquid fertilizer, A liquid trace element composite fertilizer can be used.
Examples of the solid (solid) fertilizer include vegetable or animal organic fertilizers such as oil cake, bone meal, fish cake, chicken dung, rice bran, and plant ash, and inorganic fertilizers (chemical fertilizers) made from minerals, petroleum, and the like. Known ones can be used without any particular limitation.

溶媒 Examples of the solvent for dissolving or dispersing the fertilizer component or the liquid fertilizer include water and an organic solvent, and water is preferable. However, since tap water contains chlorine and has a bactericidal action, it is preferable to use chlorine-free water, well water, spring water, and the like.

下限 The lower limit of the content of the fertilizer component in the liquid fertilizer is not particularly limited, but is preferably 0.001% by mass or more, and more preferably 0.005% by mass or more. This is because if the amount of the fertilizer component is too small, the effect of the liquid fertilizer is reduced. The upper limit of the content of the fertilizer component in the liquid fertilizer is not particularly limited, but is preferably 25% by mass or less, and more preferably 20% by mass or less. This is because if the amount of the fertilizer component is too large, it may cause an unpleasant odor.

溶媒 The content of the solvent in the liquid fertilizer is preferably 75% by mass or more, more preferably 80% by mass or more, preferably 99% by mass or less, and further preferably 95% by mass or less. If the content of the solvent is too low, the viscosity of the liquid fertilizer increases, and the handling becomes poor. Also, if the content of the solvent is too high, it is necessary to reduce the ratio of the fertilizer component.

ＣＮ The CNF content in the nutrient solution cultivation agent can be used without any particular limitation, but is preferably 0.0001% by mass or more and 10% by mass or less. If the content of CNF is too small, the effect of CNF is reduced. On the other hand, when the content is 10% by mass or more, the cultivation agent for hydroponic cultivation has a high viscosity, the sprayability is reduced, and uniform fertilization becomes difficult.

The cultivation agent for hydroponics of the present invention can be used even if a CNF dispersion alone is used. CNF is degraded at a slow rate by enzymes such as cellulase in the soil, and its degraded product, glucose, is quickly absorbed from the roots of the plant. This is because it also contributes to the effect. In addition, the CNF dispersion may use any one of softwood, hardwood, and bamboo fiber as a starting material, and use CNF obtained by the ACC method to further improve crop yield and quality. Can be. This is presumed to be due to the fact that CNF obtained by the ACC method has amphipathic properties and that none of the hydroxyl groups in the cellobiose unit are chemically modified and there are six hydroxyl groups. You.
The growth can also be promoted by spraying the CNF dispersion onto a site such as soil to which a fertilizer component such as a liquid fertilizer or a solid (solid) fertilizer has been applied. The CNF in the sprayed CNF dispersion adsorbs components necessary for plant growth in the fertilizer components in the soil and reaches the plant rhizosphere. As a result, the concentration of the fertilizer component existing in the plant rhizosphere becomes high, and the fertilizer absorption is promoted, so that the growth is further promoted. It is needless to say that the same effect as in the case of using the CNF dispersion alone can be obtained even when the cultivation agent for hydroponics comprising the fertilizer component and the CNF dispersion is used.

栽培 The cultivation agent for hydroponics of the present invention is used in hydroponics. In the present invention, hydroponic cultivation refers to a cultivation method in which components necessary for plant growth are provided as liquid fertilizer. Since liquid fertilizer does not require that various components such as fertilizer components are completely dissolved, a solid fertilizer component may be present. Here, there are several cultivation methods in the cultivation method using the liquid fertilizer, typical examples of which include a liquid fertilizer soil cultivation method in which the addition of the liquid fertilizer and irrigation are performed simultaneously, and a water medium that does not use soil as a medium. Cultivation and the like can be mentioned. Further, as another cultivation method of hydroponic cultivation, a solid medium cultivation method in which a crop is planted in a solid medium such as gravel, sand, peat, vermiculite, pumice, sawdust, rock wool, and the like, and a liquid fertilizer is supplied to the crop. Can be

The hydroponic cultivation includes submerged hydroponic cultivation in which the nutrient solution is filled, thin-film hydroponic cultivation in which the nutrient solution is flowed shallowly, and spraying in which the nutrient solution is mist-shaped with a spray pump and sprayed on roots or the like. Includes hydroponics. Hydroponics is a cultivation method generally used in plant cultivation facilities such as vegetable factories and plant factories. Naturally, the cultivation agent of the present invention can also be used in a plant factory.

方法 The fertilizer application method of the present invention is not particularly limited, but it is preferable to apply fertilizer using a hydroponic cultivation apparatus using a known mechanical means such as a drip irrigation apparatus from the viewpoint of reduction of labor for agricultural work and cost.

-Target plant-
The fertilizer for hydroponic cultivation according to the present invention reaches the plant rhizosphere after fertilization, with the CNF having a large specific surface area adsorbing the fertilizer component contained in the hydroponic cultivation agent on the surface. As a result, the concentration of the fertilizer component existing in the plant rhizosphere becomes high, and the absorption of the fertilizer is promoted. That is, in the case of the nutrient solution cultivation method using the soil as a medium, the fertilizer component of the liquid fertilizer can be efficiently used in addition to the fertilizer component existing in the soil. Here, the fertilizer component existing in the soil also includes a fertilizer component when fertilized to a specific location in advance. Further, it can be efficiently used in other cultivation methods for the same reason. Therefore, the plant to which the hydroponic cultivation agent of the present invention is used is not particularly limited, and can be used for all kinds of agricultural and horticultural crops. If you dare to exemplify plants, lettuce, rhubarb, mizuna, herbs, radish, wasabi, bensai, green soybeans, pakchoi, cabbage, rape, spring chrysanthemum, empty core, komatsuna, Chinese cabbage, sertas, tarsai, Leafy vegetables such as honeysuckle, nozawana, spinach, leek, etc., peppers, paprika, melon, bitter gourd, fruit and vegetables such as watermelon, pumpkin, blueberry, strawberry, eggplant, tomato, grape, etc. , Soybeans, bean seedlings, beans such as various sprout, flowers such as roses, grains such as rice and wheat, root crops such as lotus root, radish, bulbs such as hyacinth, crocus, tulip, Casablanca, mishimasaiko, carrot, parsley And other plants of the Umbelliferae family.

The nutrient solution cultivation agent according to the present invention suppresses the growth of bacteria, has an effect of preventing the generation of putrefaction and offensive odor, and it is not necessary or necessary to newly add a commonly used preservative. In this case, the amount of addition can be reduced.

(4) The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

<Cultivated crops; Casablanca>
In the schedule shown in Table 1, cultivation of Casablanca was performed using the same bulb. Here, the period from March 2017 to October 2017 was the first year (Comparative Example 1), and the period from November 2017 to September 2018 was the second year (Example 1).

(Example 1)
Using bamboo pulp as a raw material, 100 cc of a CNF dispersion (concentration: 0.4 wt%, average degree of polymerization: 800, degree of crystallinity: 61) was obtained by the ACC method. 10 cc of liquid fertilizer (manufactured by Sumitomo Chemical Horticultural Co., Ltd., flower factory, manufacturer guarantee sheet No. 85095, N: P: K = 5: 10: 5 Mg: 0.08 Mn: 0.004 B: 0.016) Then, 7000 cc of water was added to 100 cc of the CNF dispersion to make a total amount of 7110 cc, which was used as a cultivation agent.
Next, the bulbs of Casablanca at the end of the first year were dug up, washed, re-planted, and cultivated by nutrient solution plowing. At this time, the CNF solid content was adjusted to 0.09 g / time (concentration during fertilization: 0.006%) at a frequency of once / week, and a total of 1500 cc of the cultivation agent was fertilized.

(Comparative Example 1)
Liquid fertilizer (Sumitomo Chemical Horticultural Co., Ltd., flower factory, manufacturer guarantee voter No. 85095, N: P: K = 5: 10: 5 Mg: 0.08 Mn: 0.004 B: 0.016) Water in 10 cc 7000 cc was added to make the total amount 7010 cc.
Casablanca seedlings were purchased and cultivated by nutrient solution soil cultivation. At this time, a total of 1500 cc of the cultivation agent was applied at a frequency of once / week.

Table 2 shows the results of Example 1 and Comparative Example 1. 4 and 5 show photographs showing the results of cultivating Casablanca.

(Discussion of results)
From the results shown in Table 2, FIG. 4 and FIG. 5, the cultivation agent for hydroponics according to the present invention grew about 1.5 times as much as the liquid fertilizer not containing the CNF dispersion. Generally, it is known that the height and the number of buds in Casablanca after the second year using the bulb once bloomed gradually decrease.

<Cultivated crop; tomato (variety; Momotaro)>
(Example 2)
Using bamboo pulp as a raw material, 100 cc of a CNF dispersion (concentration: 0.4 wt%, average degree of polymerization: 800, degree of crystallinity: 61) was obtained by the ACC method. 10 cc of liquid fertilizer (manufactured by Sumitomo Chemical Horticultural Co., Ltd., flower factory, manufacturer guarantee sheet No. 85095, N: P: K = 5: 10: 5 Mg: 0.08 Mn: 0.004 B: 0.016) 7000 cc of water was added to the CNF dispersion to make a total amount of 7110 cc, which was used as a cultivation agent.

ト マ ト Next, from June 10, 2018 to July 31, 2018, tomatoes were cultivated by nutrient solution cultivation. At this time, the CNF solid content was adjusted to 0.14 g / time every week, and a total of 2500 cc of a cultivation agent was applied.

(Comparative Example 2)
Liquid fertilizer (Sumitomo Chemical Horticultural Co., Ltd., flower factory, manufacturer guarantee voter No. 85095, N: P: K = 5: 10: 5 Mg: 0.08 Mn: 0.004 B: 0.016) Water in 10 cc 7000 cc was added to make the total amount 7010 cc.
The other conditions were the same as in Example 2 to cultivate tomato.

Table 3 shows the weight of each of the tomatoes harvested in Example 2 and Comparative Example 2. FIG. 6 shows the results of changes in the amount of harvested tomatoes, FIG. 7 shows photographs showing the state of the tomatoes after harvesting the roots, and Table 4 shows the weights of the roots after each harvesting.

(Discussion of results)
From the results shown in Table 3 and FIG. 6, the cultivation agent according to the present invention has a total yield of about 1.3 times as much as the liquid fertilizer containing no CNF dispersion, and the weight per piece is about 1 times. 0.2 times and the growth amount about 1.4 times. From Table 4, the weight of the tomato root after harvest was smaller in Example 2. From the results, it can be said that the cultivation agent for hydroponics according to the present invention has an effect of increasing the yield of tomato while suppressing the growth of the root of tomato.

<Cultivated plants: 20 days radish>
(Example 3)
Using hardwood pulp as a raw material, 100 cc of a cellulose nanofiber dispersion (concentration: 0.2 wt%, average degree of polymerization: 770, degree of crystallization: 71) was obtained by the ACC method. 10 cc of liquid fertilizer (manufactured by Sumitomo Chemical Horticultural Co., Ltd., flower factory, manufacturer guarantee sheet No. 85095, N: P: K = 5: 10: 5 Mg: 0.08 Mn: 0.004 B: 0.016) The CNF dispersion was added to 100 cc of water and 7000 cc of water to give a total amount of 7110 cc.

Next, from August 12, 2018 to September 8, 2018, radish was cultivated by nutrient solution cultivation. At this time, the CNF solid content was adjusted to 0.07 g / time (concentration at fertilization 0.001%) every 4 days after the sprouts grew and grew to about 2 cm, and the number of additions was 6 times, and the total amount was 300 cc. Fertilizer.

(Comparative Example 3)
Liquid fertilizer (Sumitomo Chemical Horticultural Co., Ltd., flower factory, manufacturer guarantee voter No. 85095, N: P: K = 5: 10: 5 Mg: 0.08 Mn: 0.004 B: 0.016) Water in 10 cc 7000 cc was added to make the total amount 7010 cc.
The cultivation of radish was carried out in the same manner as in Example 3 under the other conditions.

Tables 4 and 5 show the weights of the radish portion and the stem portion of the radish radish harvested in Example 3 and Comparative Example 3, respectively. 8, 9, and 10 show photographs showing the results of cultivating radish radish of Example 3 and Comparative Example 3.

(Discussion of results)
From the results shown in Tables 5 and 6, and FIGS. 8 to 10, the radish radish cultivated using the cultivating agent according to the present invention showed 2% less radish than the liquid fertilizer without the CNF dispersion. The double growth amount and the stem portion were about 1.2 times the growth amount.

<Cultivated plants; Bean seedlings>
(Example 5)
Using bamboo pulp as a raw material, 100 cc of a cellulose nanofiber dispersion (concentration: 0.2 wt%, average degree of polymerization: 800, degree of crystallization: 61) was obtained by the ACC method. Next, from July 1, 2018 to July 13, 2018, the beans were cultivated by hydroponic cultivation. At this time, water was changed every day, and the root portion was sprayed from four sides at a rate of once / day. The total amount of CNF solids sprayed during the period was 0.01 g.

(Comparative Example 5)
The CNF dispersion was changed to water, and cultivation of beans was carried out in the same manner as in Example 5.

FIG. 11 shows photographs showing the results of cultivating the bean seedlings of Example 5 and Comparative Example 5. The right bean seedling is Example 5 and the left bean seedling is Comparative Example 5.

(Discussion of results)
From the results shown in FIG. 11, the root portion of Example 5 did not discolor and no off-flavor occurred. On the other hand, the root portion of Comparative Example 5 was discolored brown, and an off-flavor was generated. From these results, it was found that the CNF dispersion had an effect of preventing spoilage and odor.

<Cultivated plants; broccoli sprout>
(Example 6)
Using softwood pulp as a raw material, 100 cc of a cellulose nanofiber dispersion (concentration: 0.2 wt%, average degree of polymerization: 700, degree of crystallization: 63) was obtained by the ACC method. Next, during the period from August 12, 2018 to August 31, 2018, broccoli sprout was cultivated by a hydroponic method. Seeds were planted on August 12 and germinated on August 16. At this time, water was changed every day, and 1.25 cc was sprayed from four sides at a rate of twice a day from August 16 when germination occurred. The total amount of CNF solids sprayed during the period was 0.04 g. During the above period, the number of bacteria was measured by the following method.

-Bacteria count method-
A dip slide was immersed in a sample solution using a microbial simple measurement instrument “San-ai Bio Checker TTC (for measuring the total number of bacteria)” (manufactured by San-ai Sekiyu KK). Comparative evaluation was made with the table.

(Comparative Example 6)
The CNF dispersion was changed to water, and broccoli sprout was cultivated in the same manner as in Example 6, and the number of bacteria was measured in the same manner as in Example 6.

写真 FIG. 12 shows photographs showing the results of cultivating the broccoli sprout of Example 5 and Comparative Example 5. The broccoli sprout on the left side is Example 6, and the broccoli sprout on the right side is Comparative Example 6. FIG. 13 shows the bacteria measurement results.

(Discussion of results)
From the results in FIG. 12, the root portion of Example 5 did not discolor and no off-flavor occurred. On the other hand, the root portion of Comparative Example 5 was discolored brown, and an off-flavor was generated. In addition, from the results shown in FIG. 13, it became clear that the CNF dispersion had an effect of suppressing the number of bacteria. From these results, it was found that the CNF dispersion had an effect of suppressing the growth of bacteria and preventing spoilage and odor.

<Cultivated plants; cabbage>
(Example 7)
Bamboo pulp was used as a raw material to obtain 1000 cc of a cellulose nanofiber dispersion (concentration: 1.7%, average degree of polymerization: 830, degree of crystallization: 61) by the ACC method. Then, this was diluted with 20,000 cc of water (concentration at fertilization 0.081%). Next, during the period from October 17, 2018 to January 24, 2019, early cabbage and cabbage were cultivated in the field under the following conditions.
CNF diluent: once at the time of planting and once at topdressing twice (total amount of CNF solids sprayed during the period: 34 g, CNF solids per cabbage: 0.34 g)
Solid fertilizer (chemical fertilizer): once at the time of planting, twice at the top-dressing Total 3 times Pesticide: once / week Area: 35 m × 0.4 m × height = 0.2 = 2.8 m ³ (for 100 cabbage)

(Comparative Example 7)
Cabbage was cultivated in the same manner as in Example 7, except that the CNF dispersion was not used.

重量 Tables 7 to 9 show the respective weights (unit: kg) of the cabbage harvested in Example 7 and Comparative Example 7. In addition, FIGS. 14 and 15 show photographs showing intermediate results of cultivating the cabbage of Example 7 and Comparative Example 7.

(Discussion of results)
From the results shown in Tables 7 to 9, the cabbage to which CNF was added had an average growth amount of about 1.2 times that of the cabbage to which CNF was not added. In addition, from the results of FIGS. 14 and 15, it was found that there was a clear difference in the cabbage (portion to become the cabbage) in the initial stage of cultivation. From these results, it was found that the CNF dispersion had the effect of promoting the growth of cabbage and increasing the yield.

<Cultivated plants; broccoli>
(Example 8)
Using softwood pulp as a raw material, 600 cc of a cellulose nanofiber dispersion (concentration: 0.05%, average degree of polymerization: 720, degree of crystallization: 63) was obtained by the ACC method. Then, from October 7, 2018 to February 28, 2019, broccoli was cultivated in the field under the following conditions.
CNF diluent: 1 time at planting, 2 times topdressing, 3 times in total (total amount of CNF solids sprayed during the period: 0.9 g)
Solid fertilizer (Asahi Kogyo Co., Ltd., super-fast and fast-acting vegetable fertilizer N: P: K = 10: 12: 10, organic component about 30%): 1 time at planting, 2 times top dressing (every 10 days), 6 g each, total 3 Times (addition amount 18g during the period)
Water: once / day

(Comparative Example 8)
Broccoli was cultivated in the same manner as in Example 8, except that the CNF dispersion was not used.

Table 10 shows the results of measuring the amount of harvest (unit: g) of the top flower bud (edible portion) of the broccoli harvested in Example 8 and Comparative Example 8. In addition, FIG. 16 shows a photograph showing the intermediate results of cultivating the broccoli of Example 8 and Comparative Example 8. The broccoli on the right side is Example 8, and the broccoli on the left side is Comparative Example 8.

(Discussion of results)
From the results in Table 10, broccoli to which CNF was added had a growth amount about 1.5 times that of broccoli to which CNF was not added. From the results, it was found that the CNF dispersion had an effect of promoting the growth of broccoli and increasing the yield.

Claims (7)

1. 栽培 A cultivation agent for hydroponics, characterized by containing cellulose nanofibers.
2. (4) A cultivation agent for hydroponics, wherein the cellulose nanofiber according to (1) has an average thickness of 3 to 200 nm and an average length of 0.1 μm or more.
3. (4) A cultivation agent for hydroponics, wherein the cellulose nanofiber according to (1) or (2) is a cellulose nanofiber having six hydroxyl groups in a cellobiose unit and not chemically modified.
4. The cellulose nanofiber according to any one of claims 1 to 3, having an average thickness of 3 to 200 nm, a crystallinity of 50 or more, and a raw material α-cellulose content of 60 to 99% by mass. A cultivation agent for hydroponics, which is characterized in that:
5. <5> The cultivation agent for hydroponics according to any one of claims 1 to 4, wherein the cultivation agent for hydroponics is used together with a fertilizer component to increase the yield.
6. 方法 A method for hydroponic cultivation, comprising using the hydroponic cultivation agent according to any one of claims 1 to 5.
7. (6) A method for nutrient solution cultivation, comprising using the nutrient solution for nutrient solution cultivation according to any one of claims 1 to 5 at a site where a fertilizer component has been applied.

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