JP2004201518A - Culture medium bag and hydroponic method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a culture medium bag enabling easy and complete separation of roots from solid culture medium after cultivating farm product plants in solid culture medium cultivation. <P>SOLUTION: The culture medium bag is obtained by wrapping the solid culture medium with a water-permeable/root-proofing sheet having water permeability but blocking out development of the roots of farm product plants. The culture medium bag is utilized in a hydroponic method as follows: putting the culture medium bag in a cultivation container; implanting farm product plants on a place outside the water-permeable/root-proofing sheet of the culture medium bag and inside the container; cultivating the farm product plants while supplying nutritious liquid to the culture medium bag; separating the farm product plants from the culture medium bag after finishing cultivation of the farm product plants so as to reuse the culture medium bag. The culture medium bag from which the farm product plants are separated after finishing cultivation of the farm product plants, is sterilized by sunning and thereafter reused in the next hydroponics for other farm products. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
The present invention relates to a culture medium used for growing crops by a hydroponic cultivation method and a hydroponic cultivation method using the same, and in particular, using a medium bag and a medium bag capable of repeatedly reusing a solid medium. The present invention relates to a method for cultivating a crop by a hydroponic method.
[0002]
[Prior art]
The nutrient solution cultivation method (hereinafter, referred to as “solid medium cultivation method”) using a solid medium such as rock wool, rubble (pebbles), and granular ceramics is an NFT (Nutrient Film Technique) that does not use a solid medium. Since the system is simple and inexpensive compared to hydroponic cultivation such as the hydroponic method and the submerged method, it is widely used. However, solid medium cultivation has many problems unique to solid medium cultivation that do not occur in the NFT method or the liquid filling method that does not use a solid medium.
[0003]
One of the important issues to be solved is the problem of root residue treatment. Soil-borne pathogens such as ginkgo (wilt) disease and blue rot disease of tomato, and cucumber vinegar disease, survive for a long time as residues of the damaged strain, and become a source of transmission. For this reason, in order to prevent the occurrence of soil diseases in hydroponic cultivation, it is necessary to completely remove root residues at the end of cultivation. In addition, if the root residue is left as it is, the root rots and the physicochemical properties of the solid medium change. For these reasons, it is not preferable to continuously use the solid medium in which the root residue of the previous crop remains in the solid medium cultivation method.
[0004]
In NFT cultivation or flood cultivation without using a solid medium, only the root can be easily cleared at the end of cultivation. However, in the solid medium cultivation method, it is difficult to separate the root and the solid medium after the cultivation, because the roots penetrate deeply into the solid medium. In particular, when a fibrous solid medium such as rock wool is used, separation is practically difficult. In the case of using a granular medium such as Leki or ceramics, it is possible to separate the root and the solid medium, but it takes time and effort to separate, and it is difficult to completely remove even the fine roots.
[0005]
From this, it can be said that, in the solid medium cultivation method, in order to suppress the occurrence of continuous cropping failure such as soil disease and physicochemical changes in the medium, it is preferable to replace the solid medium every crop.
FIG. 3 is a conceptual diagram showing a conventional solid culture method. Fill a container for cultivation with a solid medium such as rock wool, lexi, ceramics, etc., and plant or seed the seeds of the crop, grow the crop while supplying nutrient solution to the solid medium, and grow the crop. I do. As the crop grows, the root system extends around and inside the solid medium. After the cultivation of the crop, it is difficult to separate the root of the crop from the solid medium. Therefore, the crop is discarded together with the solid medium, and only the cultivation container is reused.
[0006]
[Problems to be solved by the invention]
However, most of solid media such as rock wool, reki, and ceramics are nonflammable materials and inorganic materials that cannot be decomposed by soil microorganisms. For this reason, used solid media must be treated as industrial waste. Even when flammable organic materials such as coconut shells and cedar skin are used, it is difficult to incinerate them after use because of the burning of open fires in recent years. Must be processed. Therefore, if the solid medium is frequently replaced, the cost of purchasing a new medium, the amount of industrial waste, and the cost of treatment will increase.
[0007]
In order to promote the spread of solid medium cultivation, it is necessary to reduce the occurrence of continuous cropping failure such as soil disease while suppressing the generation of used solid medium as industrial waste. For this purpose, it is indispensable to establish a technique that allows the solid medium and the root to be easily and completely separated after completion of the cultivation.
[0008]
The present invention has been made in view of the above-described problems in solid medium cultivation, and after cultivating a crop in solid medium cultivation, a medium that can easily and completely separate a solid medium and roots. It is an object of the present invention to provide a bag and a nutrient solution cultivation method using the bag.
[0009]
[Means for Solving the Problems]
In the present invention, in order to achieve the above-mentioned object, a medium bag is used in which a solid medium is wrapped with a water-permeable root-blocking sheet that has water permeability but does not pass through the roots of the growing crop, and the crop is planted there using this as a medium. , To be grown in nutrient solution. After the cultivation of the crop, the culture medium bag was separated from the root of the crop, disinfected and reused.
[0010]
That is, the culture medium bag according to the present invention is formed by wrapping a solid culture medium with a water-permeable root-blocking sheet that has water permeability but does not allow the growing crop roots to pass through.
Further, in the nutrient solution cultivation method according to the present invention using the medium bag, the medium bag is stored in a cultivation container, and the crop is planted inside the container and outside the permeable root-shielding sheet of the medium bag. Crop is cultivated while feeding the nutrient solution to the medium bag, and after the cultivation of the crop is completed, the crop and the medium bag are separated, and the medium bag is reused. After the completion of the cultivation of the crop, the medium bag separated from the crop is sterilized with sunlight, and then reused for hydroponics of the next crop.
[0011]
When seeds and seedlings of crops are sown or settled directly on the ground, as in the case of underground cultivation, which is a common form of agriculture, the root system of the crop is usually denser as it is closer to the root of the crop and coarser as it is farther from the root of the crop. There is a tendency to distribute.
However, when the area where the root grows is limited, as in solid medium tillage, the root grows in the medium, and after the root reaches the edge of the medium, it can spread further around. Since the roots cannot be grown, the roots extend to surround the edge of the culture medium, forming a mat-like root mass. Therefore, in the solid medium cultivation method, most of the roots of the crop are distributed around the solid medium as a mat-like root mass. For this reason, most of the roots are distributed around the solid medium, and the amount of roots distributed inside the medium is relatively small.
[0012]
From this, it is considered that, in the solid medium cultivation, the nutrient solution supplied to the solid medium is not absorbed by the crop from inside the solid medium, but most of the nutrient solution is absorbed by the crop from around the solid medium. . In other words, even if the roots do not extend into the solid medium, if the roots can be sufficiently extended around the solid medium, there is no problem in growing the crop.
[0013]
Therefore, in the present invention, a method of elongating the root only around the solid medium without enlarging the root inside the medium has been considered. Specifically, a solid medium used in solid medium cultivation is wrapped with a sheet that has water permeability but no root permeability to form a medium bag, and this medium bag is used as a substitute for the conventional solid medium. I do. By performing nutrient cultivation using this medium bag in place of the solid medium, without impairing the water retention function of the solid medium, it is not necessary to infiltrate any roots in the solid medium, Unlike conventional solid medium cultivation, it is possible to easily separate and remove only roots after cultivation.
As will be described later, the growth of the crop, such as the yield of the crop, is almost the same as when the crop is planted on a solid medium.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, embodiments of the present invention will be described specifically and in detail with reference to the drawings.
FIG. 1 is a conceptual diagram showing a nutriculture method using a culture medium bag according to an embodiment of the present invention.
[0015]
First, a solid culture medium such as rock wool, lexi, ceramics, etc. with the optimal volume to be stored in a container for cultivation is prepared, and this is permeable with a water-permeable root-blocking sheet that does not pass through the roots of growing crops. Wrap to make a medium bag.
A high-density woven fabric of polyester fibers such as a root-proof water-permeable sheet that has water permeability but no root permeability (for example, manufactured by Toyobo) is suitable for the water-permeable root-blocking sheet surrounding the solid medium of the medium bag. . In addition, a sheet made of ignorant cloth or paper is not suitable for such a use since roots may penetrate into the sheet.
[0016]
It is considered that the same effect as that of the culture medium bag can be obtained by using a substance that retains water but does not allow roots to invade inside, such as a porous ceramic mass. However, in such a case, it is difficult to change the shape and volume of the culture medium in accordance with the type and time of the crop to be planted, so that the use is limited and it is considered to be impractical.
[0017]
Such a culture medium bag is filled into a container for cultivation, and a seedling of the crop is planted or seeded in the container. Thereafter, the crop is grown while supplying the nutrient solution to the medium bag, and the crop is cultivated.
As a method of supplying the nutrient solution, a general method can be appropriately selected depending on the type of the crop to be cultivated, the type of the container for cultivation, and the like. For example, a method of drip irrigation from the top of a container for cultivation or a bottom water supply for pumping a nutrient solution from the bottom side of the container by capillary action is common. In any case, the water-permeable root-blocking sheet permeates the nutrient solution into the solid medium inside the sheet, so that the solid medium retains the nutrient solution.
[0018]
As the crop grows, the root system extends between the periphery of the medium bag and the inner surface of the container so as to surround the medium bag. However, the root system does not penetrate the solid medium therein through the permeable root barrier sheet of the medium bag. On the other hand, the nutrient solution held in the solid medium is supplied to the roots of the crop through a water-permeable root-shielding sheet.
[0019]
As described above, the root system of the crop extends to surround the medium bag, but does not penetrate into the solid medium therein through the water-permeable root-blocking sheet. Can be easily separated. Also, no fine roots of the crop remain in the medium bag. For this reason, after separating the medium bag and the crop, only the crop is discarded, and both the medium bag and the container for cultivation are reused.
[0020]
In addition, the medium bag is sterilized in advance and then reused in order to remove disease bacteria. As a sterilization method, a sterilization method using ultraviolet irradiation can be applied. In particular, since the ultraviolet irradiation sterilization method using sunlight does not require any special equipment, it is easy. For example, a culture medium bag is stored in a transparent airtight bag and sterilized by exposing it to sunlight for several days. The medium bag in a clear, airtight bag is heated to tens of degrees Celsius on a sunny spring day and sterilized by both this solar heat and ultraviolet light.
[0021]
The left side of FIG. 2 shows a medium bag in which a solid medium such as rock wool, rubble, ceramics or the like is wrapped with a water-permeable root-blocking sheet that has water permeability but does not allow the roots of growing crops to pass as shown in FIG. However, the drawing on the right side of FIG. 2 is an example in which the water-permeable root-blocking sheet is doubled.
[0022]
Permeable root barrier sheets that are permeable but do not allow the growing crop roots to penetrate the crop roots at times. Since the root-shielding performance and the water-permeability of the water-permeable root-shielding sheet are contradictory, if the weave is made finer and the root-shielding performance of the crop is increased, the water-permeability is lowered, so that it is not practical.
[0023]
However, if the roots of the crop penetrate the water-permeable barrier sheet, the roots extend into the solid medium inside the medium bag, so that the medium bag cannot be used repeatedly. For example, in the case of tomato or cucumber, roots penetrate into the permeable root-shielding sheet at a rate of about 1 in 20 to 50, and this frequency increases as the number of times the permeable root-shielding sheet is used increases.
[0024]
Therefore, as shown in the right diagram of FIG. 2, when the permeable root sheet of the culture medium bag is doubled, even if the root penetrates the outer permeable root sheet, it hardly penetrates the inner permeable root sheet. It is not seen, and the recycling rate of the medium bag is dramatically increased. However, if the crop roots have penetrated the outer permeation sheet, only the inner permeation sheet and the solid medium inside can be reused, and the outer permeation sheet is discarded. There must be. Duplexing (multilayering) of the water-permeable root-blocking sheet is effective in improving the recycling rate of the culture medium bag.
[0025]
The upper right diagram (section B) in FIG. 4 shows a concept of a drip irrigation method using a rock wool solid medium as a liquid culture method using a medium bag according to another embodiment of the present invention. FIG. Most suitable for cultivation of cucumber and the like.
In this embodiment, a container having an outlet for nutrient solution is used, a medium bag wrapped with rock wool with a water-permeable root-shielding sheet is placed in this container, and a part of the water-permeable root-shielding sheet on the medium bag is removed. It opens and drip irrigation from here.
[0026]
As shown in the figure surrounded by the lower frame of FIG. 4, a liquid supply tank is arranged on a container, and a nutrient solution for liquid supply is supplied by a pump P from a nutrient solution tank arranged below and separately from the container. Assemble in the liquid supply tank. The nutrient solution in the liquid supply tank is pumped up by a capillary phenomenon of a water supply string made of a fiber material or the like, and the solution is drip-irrigated from a portion where the water-permeable root-blocking sheet is opened on a part of the medium bag. From below the container, the drainage of the nutrient solution is discharged from the outlet to the drainage tank and returned to the nutrient solution tank.
[0027]
FIG. 6 shows an example of cultivation by mixing a solid fertilizer into a solid medium in the embodiment on the right side of FIG. When water is applied to the medium bag containing the solid fertilizer, the fertilizer components of the solid fertilizer dissolve in the water and are absorbed by the roots of the crops extending around the medium bag.
The upper middle diagram (section B) in FIG. 7 is a conceptual diagram showing a bottom-water supply type nutrient cultivation method as a nutrient solution cultivation method using a medium bag according to another embodiment of the present invention. Ideal for growing tomatoes and the like.
[0028]
In this embodiment, as shown in the figure on the left surrounded by the lower frame of FIG. 7, a container having a hole on the bottom surface is used, and a water supply mat made of a fiber material or the like is stretched along the inner surface thereof, and A permeable root-blocking sheet was laid inside the liquid supply mat in which a part of the bottom surface of the mat hangs down from the hole. On the other hand, as shown in the upper right figure surrounded by the lower frame of FIG. 7, light-colored black ande soil is wrapped with a water-permeable root-shielding sheet, and the upper sheet is bound with thin strings to form a culture medium bag. Store in the container described above. A liquid supply tank is arranged below the container, and a water supply mat hanging down from the hole of the container is immersed in the nutrient solution in the liquid supply tank. The nutrient solution in the liquid supply tank is pumped up by the capillary action of the water supply mat, and the nutrient solution is supplied to the culture medium bag. In this state, the crop is planted in the corner of the medium bag and cultivated.
In the two embodiments described above, the state in which the root system of the crop is elongated, and the method of reusing the medium bag after the completion of the cultivation of the crop are exactly the same as those of the first embodiment.
[0029]
Next, examples of the present invention will be specifically described, but the present invention is not limited thereto.
(Example 1)
As shown in section B on the upper right side of FIG. 4, 1.5 liters of rock wool fine-grained cotton was used as a solid medium, which was wrapped with a root-proof water-permeable sheet (Toyobo) to form a medium bag. Cucumber was cultivated (section B). As a comparative control, cucumber was cultivated by the above-described drip irrigation method without using rock wool fine-grained cotton wrapped with a root-proof water-permeable sheet and using the solid medium as it was (section A).
[0030]
A half unit liquid of Otsuka A prescription was used as a nutrient solution, and the solution was supplied from the liquid supply tank to the culture medium using a wide water supply string made of polyester. The width of the water supply string and the position of the liquid supply tank were adjusted so that the liquid supply amount was 450 ml / hour per plant. The nutrient solution was controlled by a pouring method, in which a nutrient solution discharged without being absorbed by the crop was collected in a nutrient solution tank via a drainage tank, and was repeatedly used as a nutrient solution.
[0031]
Variety Ocean (Saitama original species) was sown on April 17, 2001, and after germination, the seeds were raised and seedlings were raised on April 24, and then transplanted to the above-mentioned hydroponic culture device on May 16. . On June 1, pinching of 15 main leaves (main branch) was performed. All children (side sticks) were pinched except for two. In addition, the first to fourth true leaves of the parent and all the children generated from these sites were removed.
[0032]
The harvest survey was conducted from June 9 at the start of the harvest to July 6 at the end of harvesting of all the finished cucumber, and the yield by grade was tabulated. The result is shown in FIG. As shown in FIG. 5, in section B using a medium bag, almost the same yield and quality as in section A using rock wool as a solid medium could be obtained.
[0033]
(Example 2)
As shown in section B in the upper center of FIG. 7, 1 liter of light-colored black ande soil was used as a solid medium, which was wrapped with a root-proof water-permeable sheet to form a medium bag, and tomato was cultivated by the above-described bottom-surface water supply method ( District B). As a comparative control, 1 liter of light-colored black ande soil was not wrapped with a root-proof water-permeable sheet, and a tomato was cultivated as it was as a solid medium by the above-described bottom water supply method (section A).
[0034]
Further, Section C, which was installed as a reference, was used for investigating the effect when there was no exchange of nutrient water between the culture medium and the roots, and a medium wrapped with an air cap sheet instead of the culture medium bag was used. . In addition, the air cap sheet made of the air cap sheet is used because the root and the bag are in close contact with each other, the air permeability is lost, and the air cap sheet having projecting bubbles is prevented in order to prevent the root from becoming anaerobic. Is used. It is used so that the projecting bubbles hit the root of the crop.
[0035]
All liquid supply was performed by bottom liquid supply using a water supply mat (trade name: Jamguard, manufactured by Toyobo). Therefore, in this experiment, the supply of liquid fertilizer to the root is only from outside the medium. As described above, the reason why the water-permeable root-blocking sheet is laid on the inside of the liquid supply mat is to prevent the root of the crop from extending out of the cultivation container.
[0036]
Seeds of tomato variety IK9O8 (provisional name) (produced by Ibaraki Keizairen) were sown on August 21, 2000, and after germination, the seeds were raised and seedlings were raised. It was transplanted to a hydroponic device. Arrangement and pruning were appropriately performed once every two weeks throughout the cultivation period. As a hormonal treatment for fruit setting, the flower clusters of tomato orchid were sprayed once a week from the flowering period of the first flower cluster on October 10 to June 11, 2001. Harvesting was conducted based on the monthly yield of salable fruits, and the survey was conducted from the start of harvesting on December 22 to July 30, 2001.
[0037]
FIG. 8 shows the result. As shown in FIG. 8, in the section C where no nutrient solution was supplied from the culture medium to the roots and only the surrounding water-permeable root-shielding sheet was supplied or the nutrient solution was supplied, the yield of 72% of the control section A was 72%. Could only be obtained. On the other hand, in the section B using the medium bag capable of supplying the nutrient solution from the solid medium to the root, 90% of the yield in the section A could be obtained. From this, it can be said that the medium bag is useful even in the bottom-feeding cultivation in which the liquid is fed only from around the medium.
[0038]
【The invention's effect】
As explained above, the culture solution cultivation apparatus and method using the culture medium bag according to the present invention enables the recycling-type solid culture medium cultivation method in which the conventionally disposable solid medium can be repeatedly used by using the culture medium bag. is there. Moreover, by using the medium bag, even if the root of the crop is not extended on the solid medium, the yield is equal to that of the conventional one in which the root of the crop is extended on the solid medium and the solid medium cannot be reused. . Therefore, it is possible to meet the technical requirements of modern agriculture, which is required to promote environmental conservation agriculture, while ensuring the yield of crops.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram showing an embodiment of a hydroponic cultivation apparatus and method using a medium bag of the present invention.
FIG. 2 is a conceptual diagram showing a modification of the medium bag shown in FIG.
FIG. 3 is a conceptual diagram showing a conventional example of a hydroponic cultivation apparatus and method using a solid medium.
FIG. 4 is a conceptual diagram showing another embodiment of the hydroponic cultivation apparatus and method using the medium bag of the present invention.
FIG. 5 is a graph showing the yield by grade in a cucumber cultivation test according to another embodiment of the hydroponic cultivation apparatus and method shown in FIG. 4, together with comparative examples.
FIG. 6 is a conceptual diagram showing a modification of the medium bag shown in FIG.
FIG. 7 is a conceptual diagram showing another embodiment of the hydroponic cultivation apparatus and method using the medium bag of the present invention.
8 is a graph showing monthly yields of fruits that can be sold in a tomato cultivation test according to another embodiment of the hydroponic cultivation apparatus and method shown in FIG. 7, together with comparative examples.

Claims (3)

What is claimed is: 1. A medium bag for cultivating crops by a nutrient cultivation method, wherein the solid medium is wrapped with a water-permeable root-blocking sheet that has water permeability but does not allow the growing crop roots to pass through. A nutrient solution cultivation method for cultivating a crop by a nutrient solution method, wherein a medium bag comprising a solid medium wrapped with a water-permeable barrier sheet that has water permeability but does not pass through the root of the growing crop is placed in a container for cultivation. The crop is planted on the inside of this container and outside of the water-permeable root-shielding sheet of the culture medium bag, and the crop is cultivated while supplying nutrient solution to the culture medium bag. A method for hydroponic cultivation using a medium bag, comprising separating the bag from the bag and reusing the medium bag for hydroponic cultivation of the next crop. 3. The method according to claim 2, wherein the medium bag separated from the crop after the cultivation of the crop is sterilized with sunlight, and then reused in the nutrient solution cultivation of the next crop. .

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