JP2023094096A - Plant cultivation medium and cultivation method - Google Patents

Abstract

To provide a plant cultivation medium that facilitates water absorption into seeds and seedlings since water absorption into seeds and seedlings was troublesome in the conventional plant cultivation medium.SOLUTION: A plant cultivation medium 31 of the present invention is a plant cultivation medium 31 comprising a fiber assembly that absorbs water using capillary action, the fiber assembly 31 being characterized in that a recess 31b is formed in the center of the upper surface side by arranging fibers having a fiber length shorter than that of fibers on the outer peripheral side at the center side. The fiber assembly is formed by winding a cloth having a long side portion and a short side portion shorter than the long side portion on the side facing the long side portion around the short side portion, and the long side portion may be arranged on the outer peripheral side.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to a plant cultivation medium and cultivation method used for hydroponics.

A hydroponics method is known in which plant seeds or seedlings are planted in a water absorbing body such as urethane or sponge, and transplanted to a growth panel to grow plants.

Patent Literature 1 discloses that factors that inhibit root elongation are reduced by using a medium in which fibers are arranged in the vertical direction.

JP 2015-188360 A

However, in the medium used in Patent Literature 1, since the seed placement portion is flat, there are cases where water absorbed in the medium cannot be efficiently supplied to plants, particularly seeds. The present invention provides a medium that can efficiently supply water to plants.

In order to solve the above problems, the plant cultivation medium of the present invention is
A medium for cultivating plants using a fiber assembly that absorbs water using capillary action, wherein the fiber assembly has fibers with a fiber length shorter than the fiber length of the fibers on the outer peripheral side arranged at the center side, A recess is formed in the center of the upper surface side.

ADVANTAGE OF THE INVENTION According to this invention, the water absorbed by the culture medium can be efficiently supplied to the plant.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of an entire cultivation instrument containing a plant cultivation medium according to an embodiment of the present invention; The figure which shows the example of preparation of the medium for plant cultivation which concerns on embodiment of this invention. The figure which shows the other Example of the medium for plant cultivation which concerns on embodiment of this invention. The figure which shows the growth process of the cultivation method which concerns on embodiment of this invention.

<Embodiment>
FIG. 1 is an exploded perspective view of the entire cultivation apparatus including a container 10 and a medium assembly 30 in which a plant cultivation medium 31 is assembled. The plant cultivation medium 31 according to the embodiment of the present invention is composed of an assembly of many fiber bundles that promote water absorption or moisture transfer.

The fiber direction of the fiber bundle forming the plant cultivation medium 31 is along the direction perpendicular to the bottom surface of the container 10, that is, along the vertical direction. Also, in the central portion, fibers with different fiber lengths are gathered so as to form a concave portion 31b, which will be described later. That is, the plant cultivation medium 31 forms a concave portion in the center of the upper surface side by arranging fibers having a fiber length shorter than that of fibers on the outer peripheral side toward the center side.

FIG. 2 shows a case where the plant cultivation medium 31 is prepared by winding a cloth. As for the shape of the cloth medium 302 that serves as the plant cultivation medium 31, for example, as shown in FIG. . The shape of the cloth culture medium 302 is obtained by weaving fibers of a predetermined length into a rectangle, and then cutting it obliquely. The dashed lines in FIG. 2(a) schematically indicate the directions of the fibers, and the lengths of the vertical and horizontal dashed lines are the fiber lengths. There is a long side 302b at the position of the side opposite to the short side 302a, and by winding the short side 302a of the cloth culture medium 302 in this shape so that the long side 302b is the outer periphery, the inclined portion 302c of the cloth is obtained. The upper surface becomes an inclined surface forming a recess 31b shown in FIG. 2(b). The short side upper portion 302d is positioned near the center of the recess 31b. By changing the inclination angle of the inclined portion 302c, it is possible to change the inclination angle of the concave portion 31b corresponding to the shape of the seed. For example, if the inclination angle of the inclined portion 302c is increased, a concave portion 31b corresponding to an elongated seed is formed. Although the configurations described above are intended to accommodate spherical or elliptical seeds, they can be adapted to a variety of shapes other than spherical or elliptical. In addition, the angle of the inclined portion from the short side to the long side may be changed in the middle, and if the fiber length before the long side is the same as the long side and the angle does not change from there, it is suitable for plant cultivation. A portion with a constant height is formed on the outer peripheral edge of the culture medium 31 . TECHNICAL FIELD The present invention relates to a medium for cultivating plants that absorbs water using capillary action, and the medium for cultivating plants has a long side and a short side shorter than the long side on a side opposite to the long side. It may be characterized in that the shaped cloth is wrapped around the short side and the long side is arranged on the outer peripheral side. In such a case, it is possible to form the concave portion 31b in the center of the upper surface side of the plant cultivation medium even with a non-knitted cloth such as felt, and supply water to the concave portion 31b using capillary action.

Since the concave portion 31b is formed in the central portion, the above shape is not limited as long as one side end is short and the other side end is long.

FIG. 2B is a schematic diagram when only one plant cultivation medium 31 is placed in the container 10 among the medium aggregates 30 . FIG. 2(b) shows a state in which the seeds 70 are placed in the concave portions 31b of the plant cultivation medium 31 while the solution 50 is poured into the container 10. As shown in FIG. In the container 10, the liquid surface of the solution 50 is positioned below the recess 31b in the vertical direction. For example, when hemp string, palm rope, or cotton thread is used as the fibrous material, there is a method of aligning the direction of the fibers in one direction, and then bundling the periphery with a fibrous material such as palm rope, hemp string, or cotton thread. In this case, in order to form the recess 31b, short fibers should be bundled around the center and then surrounded by fibers longer than the center.

Assemble the fiber bundle so that the direction of the fibers of the fiber bundle faces the top and bottom. In this way, water is absorbed against gravity from the lower part of the plant cultivation medium 31 by capillary action without applying an external force, and an appropriate amount of water is transferred to the portion of the plant cultivation medium 31 where the seeds are placed. be able to. At this time, if there is a concave portion 31b in the center as described above, water is distributed to the concave portion 31b of the plant cultivation medium 31, and water required for the seeds is flooded to the highest portion of the plant cultivation medium 31. stable supply without By forming the recess 31b in the central portion of the plant cultivation medium 31, the surface area of the seeds that come into contact with the medium increases when the seeds are placed. This makes it easier for the moisture that has moved to the concave portion 31b to come into contact with the seeds due to capillary action. By doing so, germination and raising of seedlings can be promoted more effectively than when the seed placement portion is flat, and the seeds are less likely to die due to lack of moisture.

In the plant cultivation medium 31, it is desirable that the fibers are closely spaced to each other in order to absorb moisture upward by capillary action. can be done.

Preferred materials for the plant cultivation medium 31 that can be used in the present invention include, for example, hemp cloth, hemp cord, palm rope, and cotton thread. It is preferable to use a plant cultivation medium 31 such as hemp cloth or palm rope, and materials other than those exemplified above can also be used.

As fiber properties of the plant cultivation medium 31, the wet/dry strength ratio (WS/DS) is preferably 100% or more and 150% or less, more preferably 100% or more and 130% or less. Here, the dry/wet strength ratio indicates the ratio of wet tensile strength (WS) to dry tensile strength (DS). If the dry-wet strength ratio (WS/DS) exceeds 150%, the plant cultivating medium 31 becomes hard, which may inhibit root elongation. Examples of fibrous materials that satisfy the above-mentioned preferred dry-wet strength ratio (WS/DS) include hemp and cotton. Linen and cotton have the property of becoming hard when they contain moisture. By using a material having a dry-wet strength ratio (WS/DS) of 100% or more, that is, a material that hardens when it contains water, the shape of the plant cultivation medium 31 is less likely to collapse. Such a property makes it possible to stably grasp the culture medium when carrying it out using a robot arm in the plant transplanting process, and to stably carry it to the holding position for cultivation. Furthermore, since the plant cultivation medium 31 with the recessed portions absorbs moisture and becomes hard, the plant cultivation medium 31 is less likely to be crushed during the seedling raising process, and damage to the stems can be suppressed.

Next, a suitable method for preparing the plant cultivation medium 31 will be described. There are no particular restrictions on the weaving method of the fibers arranged in the vertical direction, and cloth or the like can be used.

For example, when using a cloth culture medium 302 using a cloth formed by weaving fibers, the cloth is positioned from the short side 302a of one side edge located on the center side to the other side edge located on the outer peripheral side. It becomes longer toward the long side 302b of the portion. As a method of preparing the plant cultivation medium 31 using cloth, for example, there is a method of winding the cloth around the short side of the lateral end of the cloth toward the long side of the lateral end. In this case, the short side 302a of the side edge is located on the center side of the recess 31b, and the short side upper portion 302d of the side edge is the center of the recess 31b.

FIG. 3 shows a fiber assembly 400 as an example of the plant cultivation medium 31 in which the recesses 31b are bundled with different fiber lengths such that the fiber direction is along the vertical direction. It is formed by aggregating different fibers into a rectangular parallelepiped shape. The fibers used here are palm rope, hemp string, cotton thread, and the like. If short fibers are aggregated in the central portion and surrounded by longer fibers than the central fibers, the fiber assembly 400 may be arranged in a rectangular parallelepiped shape, or in a cylindrical or prismatic shape. You can arrange them.

In the fiber assembly 400, short fibers are gathered in the center, fibers longer than the short fibers in the center are brought into close contact with each other, and further long fibers are brought into close contact with the surroundings. Here, the concave portion 400a positioned above the central staple fiber corresponds to the concave portion 31b of the plant cultivation medium 31. As shown in FIG. At this time, by adopting a configuration in which the periphery of the fiber assembly 400 is tightened with a fiber material, the degree of adhesion between the fibers of the fiber assembly 400 can be increased.

By forming the recessed portion 400a for positioning the seed, which is composed of fibers of different fiber lengths, the seed placed on the recessed portion 400a of the fiber assembly 400 is supplied with the moisture necessary for germination, and the seeds are prevented from withering during germination and growth. can be suppressed.

Next, an example of a suitable cultivation method using the plant cultivation medium 31 according to the embodiment of the present invention will be described below.

The cultivation method according to the present invention may be characterized by using the above-described plant cultivation medium 31 and absorbing water from below the recessed portions 31b of the plant cultivation medium 31 during plant cultivation. The term “plant-growing time” refers to a period during which seeds sown in the recessed portions 31b of the plant-cultivating medium 31 germinate and grow until harvest. This cultivation method is particularly suitable for artificial light type hydroponic cultivation using a light source such as an LED.

For example, when performing artificial light type hydroponics using leaf lettuce, seeds are placed in the upper part of the recess 31 b of the plant cultivation medium 31 . As shown in FIG. 2(b), when the solution 50 is poured into the container 10, the seeds absorb moisture located below the concave portion 31b, thereby supplying moisture to the seeds for germination (germination step). After germination, the plant cultivation medium 31 always absorbs water and the seedlings after germination grow until harvesting. (Growth process)

As a cultivation environment for leaf lettuce using the plant cultivation medium 31, the temperature in the cultivation space is 20 to 25° C., and the humidity in the cultivation space is 60 to 80%. The cultivation space temperature and the cultivation space humidity can be appropriately changed according to the type of plant.

In the germination step, it is desirable to use a cultivation container or water tank that can maintain a water level always lower than the recess 31b. In the germination step of the present embodiment, the water immersed in the recess 31b or lower of the plant cultivation medium 31 placed in the container 10 may remain, and the water in the container 10 may be running water. good too.

In the growth process, the fibers in the lower part of the concave portion 31b of the plant cultivation medium 31 are immersed in water, and the plant cultivation medium 31 that supports the germinated seedlings is always in a state where the entire medium absorbs moisture. . In the cultivation tank 12 shown in FIG. 4 , the plant cultivation medium 31 for the cultivation process is arranged in the cultivation hole 60 b of the cultivation panel 60 . This growing panel 60 is placed on top of a water tank 11 flooded with a solution 50 containing nutrients necessary for plant cultivation. The water level of the solution 50 is positioned below the recessed portions 31b of the plant cultivation medium 31 . The solution used in the growth process may be either running water or flooded water in the water tank 11 . At this time, a cup made of resin or the like may be installed in the growth hole 60 b of the growth panel 60 . Here, the height of the water tank 11 is preferably lower than the highest portion of the plant cultivation medium 31 inserted into the cultivation hole 60 b of the cultivation panel 60 . Further, when the surface of the growing panel 60 on which the growing holes 60b are formed is attached to the water tank 11 so as to be positioned lower than the height of the water tank 11 and lower than the recessed part 31b of the plant cultivation medium 31, the recessed part is formed. It is possible to prevent the seeds in 31b from being submerged in water.

By using a material that has a dry-wet strength ratio of 100% or more, that is, a material that makes the plant cultivation medium 31 hard when wet, the transplanting work is easy. Alternatively, a plurality of growing panels having growing holes formed at different intervals according to the growth of the plant may be prepared and the transplanting operation may be performed multiple times.

<Example 1>
In order to cultivate leaf lettuce, a plant cultivation medium 31 made of hemp cloth was prepared. The dry-wet strength ratio (WS/DS) of the linen medium used in this example was 118%. As for the shape of the cloth, the one shown in FIG. 2(a) was used. As shown in FIG. 2(b), the seeds 70 at the time of sowing were placed so that the seeds 70 were in contact with the surfaces of the recesses 31b.

Cultivation of leaf lettuce was carried out using the medium 31 for plant cultivation. Specifically, it is an artificial light-type hydroponic culture using LEDs as a light source, and includes a process of sowing and germinating leaf lettuce seeds (germination process) and a process of growing the seedlings grown in the germination process until harvesting (growth process).

In this example, leaf lettuce was cultivated using a white LED as a light source. The temperature of the cultivation space in the germination process and the growth process was kept constant at 22°C, and the humidity in the cultivation space was controlled at 70%. As the water used for hydroponics, a solution containing nutrients necessary for plant cultivation was used, and cultivation was carried out with a solution having an EC (electrical conductivity) value of 2.0 mS·cm ⁻¹ .

The water used in the germination process was a solution containing nutrients necessary for plant cultivation. In this germination process, it was confirmed that 100 out of 100 sown leaf lettuce germinated 7 days after sowing.

In the growth process, the plant cultivation medium 31 that supports the seedlings grown in the germination process is transplanted into the growth hole 60b of the growth panel 60, the growth panel 60 is installed in the upper part of the water tank 11, and the growth panel 60 is positioned 40 cm above the growth panel 60. Cultivation was performed with the LED installed. As for the amount of light in the growing process, the photon flux density (PPFD) on the surface of the growing panel 60 was 180 μmol·m ⁻² ·s ⁻¹ . In the growing process, the seedlings cultivated for 14 days in the germination process were transplanted to the growing panel 60 and cultivated in the water tank 11 filled with the solution for 28 days. As a result, the average weight of leaf lettuce stems and leaves was 128 g.

<Example 2>
In this example, the fiber assembly 400 shown in FIG. 3 was used. The structure of the fiber assembly 400 is a structure in which palm ropes are aggregated, and the fiber assembly 400 is made by making rope-like fibers into a plurality of fibers with different lengths, and centering on an assembly of short lines of the rope-like fibers. They were arranged, and the fibers having a fiber length longer than that of the center fiber were brought into close contact with each other. Furthermore, it was produced by adhering it with a fiber having a longer fiber length than the central two types of fibers having different lengths.

In Example 2, the plant was immersed in the solution and cultivated so that the water level was lower than the recess 400a. In Example 2, leaf lettuce was cultivated in the same manner and under the same conditions as in Example 1 except for the fiber assembly 400 as the plant cultivation medium 31 . In the germination process, it was confirmed that 99 out of 100 sown leaf lettuce germinated 7 days after sowing. After cultivating for 14 days in the germination process, the fiber assembly 400 supporting the grown seedlings was transplanted to the growing panel 60, and then cultivated for 28 days in the water tank 11 filled with the solution. As a result, the average weight of leaf lettuce stems and leaves was 149 g.

In Example 1, the fiber length varied continuously, but in this example, fibers with three different lengths were used. The change in fiber length may be continuous or stepwise, and the use of three or more types of fibers with different lengths facilitates increasing the contact area with seeds.

10 container 11 water tank 12 cultivation tank 31 plant cultivation medium 31b concave portion 50 solution 60 growing panel 70 seed 302 fabric medium 302a short side 302b long side 302c inclined portion 302d short side upper portion 400 fiber assembly 400a concave portion

Claims (7)

A medium for cultivating plants with a fiber assembly that absorbs water using capillary action,
A medium for cultivating a plant, wherein the fiber assembly has a recess formed in the center of the upper surface side by arranging fibers having a fiber length shorter than that of fibers on the outer peripheral side at the center side. 2. The plant cultivation medium according to claim 1, wherein three or more types of fibers having different lengths are used in said fiber assembly. The fiber assembly is
A cloth having a shape having a long side and a short side shorter than the long side on the side facing the long side,
3. The plant cultivation medium according to claim 1, wherein the medium is formed by being wound around the short side portion, and the long side portion is arranged on the outer peripheral side. A plant cultivation medium that absorbs water using capillary action,
The plant cultivation medium is
A cloth having a shape having a long side and a short side shorter than the long side on the side facing the long side,
A medium for plant cultivation, wherein the medium is formed by being wound around the short side portion, and the long side portion is arranged on the outer peripheral side. The plant cultivation medium according to any one of claims 1 to 4, wherein the fiber assembly hardens when it absorbs water. 6. The medium for plant cultivation according to claim 5, wherein the fiber aggregate has a dry-wet strength ratio of 100% or more and 150% or less. A cultivation method using the plant cultivation medium according to any one of claims 1 to 6,
A method for cultivating a plant, wherein the liquid surface of a solution for cultivating the plant is located below the recess.

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