JP2014132870A - Plant cultivation instrument and plant cultivation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plant cultivation instrument in which a plant growth rate is good and mold does not occur.SOLUTION: A plant cultivation instrument is supplied with nourishing solution 3 in the undersurface side of an imperforate hydrophilic film 2 substantially capable of integrating with roots of a plant body. And in the plant cultivation instrument which grows a plant on the film 2, the imperforate hydrophilic film 4 does not contain a plasticizer, and the degree of swelling is 160%-300%.

Description

The present invention relates to a plant cultivation instrument and a plant cultivation method. More specifically, the present invention relates to a plant device using a nonporous hydrophilic film and a plant cultivation method using the film.

The present inventors have developed a plant cultivation tool and a plant cultivation method (Patent Document 1) for cultivating a plant by integrating the film and plant roots on a nonporous hydrophilic film that is in contact with a nutrient solution. Plant cultivation instrument and plant cultivation method (Patent Document 2) for irrigating the upper part of the film, plant cultivation instrument and plant cultivation method (Patent Document 3) through which a plant root penetrates a part of the film, and the above A plant cultivation system (Patent Document 4) in which the film continuously moves on the nutrient solution, and further a plant cultivation system (Patent Document 5) in which an air layer is provided between the film and the evaporation suppression member disposed above the film. The plant cultivation system (patent document 6) using the means to supply a nutrient solution continuously to the lower surface side of the said film is disclosed.
No. 2004-64499 Japanese Patent No. 4425244 JP 2008-61503 A JP 2008-182909 JP 2008-193980 A Japanese Patent No. 4142725

The plant cultivation apparatus and the plant cultivation method using the known nonporous hydrophilic film are problems of conventional soil cultivation and hydroponics. It has solved problems such as accumulation of salt in and fertilizer outflow, large amount of water consumption, expensive capital investment, and inability to produce high quality crops.

On the other hand, when the plant cultivation apparatus and the plant cultivation method using the known nonporous hydrophilic film are used, the present inventors generate mold on the surface of the nonporous hydrophilic film, and the plant growth rate. Has faced the problem of being slow.

The object of the present invention is to solve the problem of mold generated on the surface of the nonporous hydrophilic film and the problem that the plant growth rate is slow, and an apparatus for plant cultivation and plant cultivation using the nonporous hydrophilic film. It is to provide a method.

As a result of intensive studies, the present inventors have found that the cause of mold generated on the surface of the nonporous hydrophilic film is the plasticizer contained in the nonporous hydrophilic film.

Furthermore, the present inventors have found that the degree of swelling of a nonporous hydrophilic film in water correlates with the growth rate of plants cultivated on the film, thereby completing the present invention.

The plant cultivation instrument of the present invention is based on the above findings, and more specifically, supplies water or nutrient solution to the lower surface side of the nonporous hydrophilic film that can be substantially integrated with the roots of the plant body, A plant cultivation device for cultivating a plant on a film, wherein the nonporous hydrophilic film does not contain a plasticizer and has a swelling degree of 160% to 300%. .

Furthermore, the present invention provides the nonporous film described above, wherein the nonporous hydrophilic film that can be substantially integrated with the roots of the plant body does not contain a plasticizer, and the degree of swelling is 160% to 300%. This is a plant cultivation method in which water or nutrient solution is supplied to the lower surface side of a hydrophilic film, and plants are grown on the film.

In the plant cultivation device of the present invention having the above-described configuration, the nonporous hydrophilic film that can be substantially integrated with the roots of the plant does not contain a plasticizer that is a causative agent for mold generation, and therefore is a known nonporous material. Generation of mold, which has been a problem with plant cultivation equipment using a hydrophilic hydrophilic film, is avoided.

Further, in the plant cultivation instrument of the present invention having the above-described configuration, the lower surface of the film is set by setting the swelling degree of the nonporous hydrophilic film that can be substantially integrated with the roots of the plant within a specific range. The permeation rate of the fertilizer component in the nutrient solution supplied to is increased, and the growth rate of plants cultivated on the film is increased.

Moreover, according to the plant cultivation method of the present invention having the above-described configuration, generation of mold during cultivation is suppressed, so that the use of agricultural chemicals such as fungicides can be reduced.

In addition, according to the plant cultivation method of the present invention having the above-described configuration, generation of mold during cultivation is suppressed, so contamination of the crop with mold is avoided, and the excellent product rate of the crop is improved.

Further, according to the plant cultivation method of the present invention having the above configuration, the permeation rate of the fertilizer component in the nutrient solution supplied to the lower surface of the film is increased, and the cultivation period is shortened by increasing the growth rate of the plant, Harvest time is advanced.

Furthermore, according to the present invention, since the root of the plant and the ground soil are isolated by the water-impermeable material and are not in direct contact with each other, even if the soil in the ground is contaminated with pathogenic microorganisms, pathogenic microorganisms, Since bacteria cannot permeate the film, they do not touch the roots and can avoid plant contamination such as continuous cropping damage.

Furthermore, according to the present invention, even if the ground soil is contaminated with residual pesticides and the like, contamination of the plant is reduced because the ground soil and the root are isolated by the water-impermeable material.

Furthermore, according to the present invention, the water-impermeable material on the ground soil can be used even when a nutrient solution is supplied to the water-absorbing material installed between the film and the nonporous hydrophilic film. Prevents the transfer of nutrient solution into the soil, prevents salt accumulation and groundwater contamination, and at the same time reduces cultivation costs such as effective use of valuable water resources and reduction of fertilizer use.

Moreover, even if there is salt accumulation on the surface layer of the earth soil, there is a water-impermeable material, so there is no direct contact with the roots, and accumulated salts do not significantly affect plant growth.

Furthermore, the plant cultivation method of the present invention makes it very easy to control the water stress caused by the nonporous hydrophilic film on the plant to be cultivated, and the quality of the plant can be improved.

Hereinafter, the present invention will be described more specifically with reference to the drawings as necessary. Regarding such a configuration (or function), reference can be made to “detailed description of the invention”, “examples”, and the like of documents (Patent Documents 1 to 6) by the present inventor as necessary.

(Plant Cultivation Device) FIG. 1 is a schematic cross-sectional view showing a basic embodiment of the plant cultivation device of the present invention. With reference to FIG. 1, the plant cultivation instrument of this aspect is a nonporous hydrophilic film 1 in which a plant body 7 is to be placed on a nutrient solution 3 held in a container 2 (water-impermeable material). Is placed.

In order to promote the “integration” of the film 1 and the root 8, it is preferable to supply a nutrient solution from below the film 1. The present inventors have used a 40 μm-thick polyvinyl alcohol (PVA) film as a nonporous hydrophilic film, and investigated the effect of fertilizer concentration supplied from under the film on the integration phenomenon of roots and film. It was. Specifically, about 300 ml of vermiculite or rock fiber is placed as a soil on a non-porous hydrophilic film (PVA) of about 20 cm × 20 cm. 2) were planted.

As a nutrient solution supplied from under the film, a total of six types of systems were prepared using Hyponex 100-fold diluted solution, 1000-fold diluted solution, and water (tap water, ie, no fertilizer). The amount of nutrient solution was 300 ml each, and the thickness of the soil on the film (PVA) was about 2 cm. The experiment was performed in a house, using natural light, under conditions of an air temperature of 15 to 25 ° C. and a humidity of 50 to 90% RH. After 13 days and 35 days after the start of cultivation, the peel strength was measured in the same manner as the integration test described later. The results are shown in Table 1.

As is apparent from Table 1, not only the growth of the plant but also the adhesion strength between the root and the film was remarkably improved when the nutrient solution was used, compared with the case where only water was supplied from the lower surface of the film. This indicates that the plant absorbs not only water but also fertilizer components through the film. Furthermore, in order to efficiently absorb water and fertilizer components through the film, it is essential that the roots adhere strongly to the film surface, and as a result, the root and film are considered to be integrated. .

If too much water is added from above the film before the “unification” of the non-porous hydrophilic film 1 and the root 8 is completed, the plant absorbs easy moisture on the film and moisture from under the film is absorbed. The need to remove, and as a result, the roots tend to become less integrated with the film. Therefore, it is not preferable to add excess moisture from above the film until the roots are integrated with the film. On the other hand, if the root is integrated with the non-porous hydrophilic film, moisture / nutrient may be appropriately applied from above the film.

(Nonporous hydrophilic film) In the plant cultivation instrument of the present invention, a nonporous hydrophilic film for cultivating a plant thereon is essential. The nonporous hydrophilic film used in the present invention preferably satisfies all the various physical properties described below.

(Integration Test) It is important that the nonporous hydrophilic film is a film that can be “substantially integrated with the roots of the plant” that is being cultivated. “A film that can be substantially integrated with the roots of a plant” means that when a plant is grown for 35 days on the nonporous hydrophilic film of the plant cultivation system of the present invention, the nonporous hydrophilic film is formed. It is a film having a peel strength of 10 g or more for peeling from the roots of cultivated plants. The “integration test” for measuring the integration of root and film can be performed as follows.

Using the "Zaru Bowl Set", put the film to be tested (200 x 200mm) on the sieve, place 150g of vermiculite (water 73%, dry weight 40g) on the film, and seedlings of Sunny lettuce (one real leaf) 2) are planted. The rice cake is placed in a bowl filled with 240 to 300 g of nutrient solution, and the film is brought into contact with the nutrient solution to grow seedlings. Cultivation is carried out in a house, using natural light, temperature is 0-25 ° C., humidity is 50-90% RH for 35 days. Next, the stems and leaves are cut at the base of the cultivated plant, and the film is cut into a width of 5 cm (length: about 20 cm) so that the stem of the film with which the roots are closely attached is approximately in the center, thereby obtaining a test piece.

A commercially available clip is attached to the spring-type hand balance, and one of the test pieces obtained above is fixed with the clip, and the weight indicated by the spring-type hand balance (corresponding to the weight of the test piece = A gram) is recorded. Next, the stalk at the center of the test piece is held by hand and gently pulled downward, and the weight (load = B grams) when the root and film are separated (or cut) is read from the scale of the spring-type hand balance. The (B-A) gram obtained by subtracting the initial weight from this value is defined as a 5 cm wide peel load, and this peel load is defined as the peel strength.

The peel strength of the nonporous hydrophilic film used in the present invention is preferably 10 g or more, more preferably 30 g or more, and most preferably 100 g or more.

(Ion permeability test) Further, in the present invention, as one of the indicators for judging whether or not the nonporous hydrophilic film can be “substantially integrated with the root of the plant”, the ion permeability Balance is mentioned. When a plant is cultivated using the plant cultivation system of the present invention, the plant absorbs fertilizer as ions through the film. Therefore, the salt (ion) permeability of the film used affects the amount of fertilizer components given to the plant. In the present invention, electrical conductivity measured at the cultivation temperature of water and salt water when water and 0.5% by mass salt water are opposed to each other for 4 days (96 hours) through a nonporous hydrophilic film. A film having a difference in degree (EC) of 4.5 dS / m or less is preferable. The difference in electrical conductivity between water and salt water is more preferably 3.5 dS / m or less, and most preferably 2.0 dS / m or less. When such a film is used, it becomes easy to supply a suitable water or fertilizer solution to the roots and promote the integration of the film with the roots.

Electrical conductivity (EC, EC) is an index of the amount of salts (or ions) dissolved in the liquid, and is also referred to as specific conductivity. As EC, the value of electrical conductivity when two electrodes having a cross-sectional area of 1 cm 2 are separated by a distance of 1 cm is used, and the unit is Siemens (S), which is expressed by S / cm. However, since the EC of the nutrient solution is small, mS / cm, which is a unit of 1/1000, is used (in the international unit system, dS / m (d is deci)).

The ion permeability of the film can be measured as follows. 10 g of commercially available salt is dissolved in 2000 ml of water to make 0.5% salt water (EC: about 9 dS / m). Using the “Zaru Bowl Set”, place the film to be tested (size: 200-260 × 200-260 mm) on the sieve and add 150 g of water onto the film. On the other hand, 150 g of the above salt water is added to the bowl side, and the entire system obtained is wrapped with food wrap (polyvinylidene chloride film, trade name: Saran Wrap (registered trademark), manufactured by Asahi Kasei Co., Ltd.) to prevent evaporation of moisture. In this state, it is allowed to stand at room temperature, and ECs on the water side and salt water side are measured every 24 hours. Specifically, a small amount of sample (that is, a solution on the water side or the salt water side) is placed on the measurement site (sensor unit) of the electric conductivity meter using a dropper, and the conductivity is measured.

(Water Permeability / Glucose Solution Permeability Test) In the present invention, the nonporous hydrophilic film is a predetermined one from the viewpoint of facilitating nutrient (organic matter) absorption of plant roots via the nonporous hydrophilic film. It is preferable to show glucose permeability. This film having excellent glucose permeability is obtained at the cultivation temperature of water and glucose solution when water and 5% glucose aqueous solution are brought into contact with each other for 3 days (72 hours) through a nonporous hydrophilic film. The film has a difference in measured concentration (Brix%) of 4 or less, more preferably 3 or less, more preferably 2 or less, and most preferably 1.5 or less.

The glucose permeability of the film can be measured as follows. A 5% glucose solution is prepared using commercially available glucose (glucose). Using the same “Zeru bowl set” as in the ion permeability test above, place a nonporous hydrophilic film (size: 200-260 × 200-260 mm) to be tested on the pouch and add 150 g of water onto the film. . On the other hand, 150 g of the above glucose solution is added to the bowl side, and the entire system obtained is wrapped in a food wrap (polyvinylidene chloride film, trade name: Saran Wrap, manufactured by Asahi Kasei Co., Ltd.) to prevent evaporation of moisture. In this state, the sample is left at room temperature, and the sugar content (Brix%) on the water side and glucose solution side is measured with a saccharimeter every 24 hrs.

(Water pressure resistance) Further, in the present invention, the nonporous hydrophilic film preferably has a water impermeability of 10 cm or more as the water pressure resistance. When such a nonporous hydrophilic film is used, the integration of the root and the film can be promoted. In addition, it becomes easy to prevent pathogen contamination through a suitable oxygen supply to the roots and the nonporous hydrophilic film.

The water pressure resistance can be measured by a method according to JIS L1092 (Method B). The water pressure resistance of the nonporous hydrophilic film used in the present invention is preferably 10 cm or more, more preferably 20 cm or more, still more preferably 30 cm or more, and particularly preferably 200 cm or more.

(Material) The material of the nonporous hydrophilic film used in the present invention is not particularly limited, and can be appropriately selected from known hydrophilic materials that can be used in the form of a film or a film. . Specific examples include hydrophilic materials such as polyvinyl alcohol (PVA), cellophane, cellulose acetate, cellulose nitrate, ethyl cellulose, and polyester. The thickness of the nonporous hydrophilic film is not particularly limited, but is usually 300 μm or less, preferably 5 to 200 μm, more preferably 20 to 100 μm.

The nonporous hydrophilic film used in the present invention preferably satisfies all of the above physical properties (ion permeability, glucose permeability and water pressure resistance). The present inventors evaluated the physical properties of various nonporous hydrophilic films and a comparative porous hydrophobic film by the method described above. Specifically, ion permeability was tested for six types of PVA, biaxially stretched PVA (boblon), hydrophilic polyester, cellophane, PH-35, and ultrafine fiber nonwoven fabric (Charelia), and PVA, biaxially stretched PVA, Glucose permeability was tested for five types of cellophane, penetrating cellophane, and PH-35, and water resistance was tested for five types of PVA, biaxially stretched PVA, cellophane, hydrophilic polyester, and ultrafine fiber nonwoven fabric. The results are shown in Tables 2 to 4 below.

As is apparent from Table 2, the films having a large ion permeability were superfine fiber nonwoven fabric (Charelia), PVA, hydrophilic polyester and cellophane. On the contrary, the one having a small ion permeability was bobron, and the one having no ion permeability was a microporous polypropylene film (PH-35). Therefore, it can be seen that the microporous polypropylene film (PH-35) is unsuitable from the viewpoint of ionic salt permeability.

As is apparent from Table 3, among the five films tested, PVA, cellophane and osmotic cellophane had good glucose permeability, but almost no glucose permeability was observed with bobron. Further, no permeability was observed with PH-35. From the viewpoint of glucose permeability, it can be seen that films that can be suitably used in the present invention are PVA and cellophane.

As is apparent from Table 4, from the viewpoint of the water pressure resistance of the film, a porous film such as an ultrafine fiber nonwoven fabric cannot be used in the present invention.

As is apparent from the data shown in Tables 2 to 4, films satisfying all of ion permeability, glucose permeability and water resistance are nonporous hydrophilic films such as PVA, cellophane and hydrophilic polyester. It is. Therefore, in the present invention, a nonporous hydrophilic film is used.

(Plasticizer for Film 1) The nonporous hydrophilic film 1 used in the present invention must contain no plasticizer. In general, a plasticizer is added to a film material for the purpose of improving workability when forming the film or for providing flexibility to the film. However, according to studies by the present inventors, glycerin and the like used as the plasticizer cause mold generation in a plant cultivation environment.

In order to obtain the film 1 containing no plasticizer, the film may be formed without adding the plasticizer added in the normal film production process. Alternatively, the plasticizer contained in the film 1 may be removed by immersing and washing the film 1 in a solvent in which the plasticizer dissolves after forming the film 1 containing the plasticizer in a normal manufacturing process. . For example, in the case of a polyvinyl alcohol film containing glycerin as a plasticizer, by immersing the film in water and washing with water, the glycerin as a plasticizer can be removed, and a film 1 containing no plasticizer can be obtained. it can.

(Swelling degree of film 1) The swelling degree of the film 1 used in the present invention in water (at 25 ° C) is preferably 160% to 300%, more preferably 180% to 270%. . If the degree of swelling of film 1 in water (25 ° C.) is below this range, the permeation rate of nutrients in the film will be slow and the growth rate of plants will be slow, which is not preferable. On the other hand, if it exceeds this range, the film strength in the swollen state becomes weak, and the roots of the plant tend to penetrate the film, which is not preferable.

The degree of swelling of the film 1 in water can be adjusted by changing the degree of crosslinking of the hydrophilic polymer constituting the film 1. When the degree of crosslinking is increased, the degree of swelling of the film 1 is decreased, and when the degree of crosslinking is decreased, the degree of swelling of the film 1 is increased. Therefore, the degree of swelling of the film 1 in water can be arbitrarily set by adjusting the degree of crosslinking of the hydrophilic polymer constituting the film 1.

(Measurement method of swelling degree) The swelling degree of the film 1 in water (25 ° C) can be measured as follows. Cut the dried film 1 into 15 cm × 15 cm and immerse it in 1 L of distilled water at 25 ° C. for 4 hours. The swollen film 1 is taken out of the water, the water adhering to the film surface is wiped off, and the weight of the swollen film is measured immediately. The swollen film is then air dried for 24 hours and the weight of the dried film is measured. Swelled film weight ÷ dry film weight × 100 is obtained for two sheets, and the average (n = 2) is defined as the degree of swelling of film 1.

(Nutrient Solution) The nutrient solution (or fertilizer solution) usable in the present invention is not particularly limited. For example, any of the nutrient solutions that have been used in conventional soil culture or hydroponics and hydroponics can be used in the present invention.

In general, as inorganic components indispensable for the growth of plants as water or nutrient solution, as main components: nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), Sulfur (S) and trace components include: iron (Fe), manganese (Mn), boron (B), copper (Cu), zinc (Zn), and molybdenum (Mo). In addition, there are silicon (Si), chlorine (Cl), aluminum (Al), sodium (Na) and the like as subcomponents. If necessary, other physiologically active substances can be added as long as the effects of the present invention are not substantially inhibited. Furthermore, sugars such as glucose (glucose), amino acids and the like can be added.

(Additional Means) In the embodiment shown in FIG. 2, if necessary, the support 4 for plant cultivation such as soil and / or water vapor does not pass through or is low permeation on the nonporous hydrophilic film 1. Evaporative suppression member 5 (for example, a mulching material described later) can be disposed. By disposing such an evaporation suppressing member 5, water vapor evaporated from the nonporous hydrophilic film 1 into the atmosphere is condensed on the surface of the evaporation suppressing member 5 or the plant cultivation support 4, so that plants can be used as water. .

(Multing Material) In the present invention, so-called “mulching” can also be used preferably. Here, “marting” refers to a material such as a film used for applying heat insulation, cold protection, drying prevention, etc. to the roots and trunks to help the plant grow. When such mulching is used, it is possible to obtain an advantage that the effective utilization of moisture is increased.

That is, in the plant cultivation apparatus according to the present invention, water and nutrients transferred from the lower part of the nonporous hydrophilic film 1 into the nonporous hydrophilic film 1 are directly absorbed by the plant roots integrated with the film 1. In addition, there is a tendency to evaporate from the surface of the film 1 as water vapor. Thus, the upper part of the nonporous hydrophilic film 1 can be covered with the mulching material 5 so as to prevent the vaporized water from escaping into the atmosphere as much as possible. By covering with the mulching material 5, water vapor is condensed on the surface of the mulching material 5 or the support surface for plant cultivation, so that plants can be used as water.

(Plant Cultivation Support) As the plant cultivation support 4, any commonly used soil or medium can be used. Examples of such soil or medium include soil used for soil cultivation and medium used for hydroponics.

For example, natural sand, rubble, pumice sand, etc. for inorganic materials, and rock wool, vermiculite, perlite, ceramic, rice husk charcoal, etc. for processed products (high temperature firing etc.). In organic systems, there are synthetic granular phenolic resins such as natural peat moss, coconut fiber, bark medium, rice husk, neat and sotan. A mixture of these may also be used. Synthetic fiber cloth or non-woven fabric can also be used. Minimal fertilizer and trace elements may be added to these soils or media. According to the knowledge of the present inventors, until the root of the plant grows to an extent capable of absorbing water or nutrients from the soil in contact with the film 1, in other words, the nutrient until the root and the film 1 are integrated. Is preferably added to the support for plant cultivation on the film 1 as “minimum fertilizer and trace elements” mentioned here.

Furthermore, if necessary, irrigation means (for example, an infusion tube) for intermittently supplying water or nutrient solution can be disposed on the nonporous hydrophilic film 1. By arranging such irrigation means, it is possible to obtain the merit that when the water or fertilizer component that the plant ingests via the nonporous hydrophilic film is insufficient, it can be supplemented.

Further, if necessary, a fine mist spraying means 6 (for example, a valve) is placed on the upper part of the cultivation area containing the nonporous hydrophilic film 1, and water, nutrient solution or agrochemical dilution is sprayed intermittently. be able to. By disposing such means for fine mist spraying, especially in the summer season by intermittent spraying of water, cooling of the environment by spraying of nutrient solution and supply of fertilizer components by foliar spraying, water mixed with pesticides or The merit that automation of spraying of agricultural chemicals by spraying of nutrient solution becomes possible can be obtained. In the configuration of FIG. 2, the configuration other than the above is the same as that in FIG.

Hereinafter, the present invention will be described more specifically with reference to examples.

Example 1 EC2 nutrient solution (Otsuka House 1: 2: 5: 20: 30: 1, Otsuka Chemical Co., Ltd.) 3 L was added to a plastic tray (inner size 34 cm × 24 cm × depth 5 cm) and cut into 45 cm × 35 cm. Four types of polyvinyl alcohol (PVA) films with a thickness of 50μm, which do not contain a plasticizer, and have different degrees of swelling (swelling degree = 160%, 186%, 238%, 270%)
Was placed on the nutrient solution. On the film, peat moss (Peat Van, Sakata Seed Co., Ltd.) was loosened and placed at a thickness of 0.5 to 0.7 cm. Covered with a silver multi-film (manufactured by Dongguan Kosan Co., Ltd.) with X-marked holes for seedling planting at intervals of 10 cm x 12 cm, lettuce seedlings (green jacket, tachy seeds (10) Strain)) 6 strains were planted on each film.

Using a straight tube white fluorescent lamp (40W) as a light source, the plant was cultivated for 3 weeks with a light illuminance of 5,000 lux and a room temperature of 25 ° C. with a light time of 16 hours and a dark time of 8 hours. Six lettuce strains were harvested from each tray and weighed. The yield of each swelling degree film was as follows: swelling degree 160%: 19.4 g, swelling degree 186%: 35.4 g, swelling degree 238%: 47.5 g, swelling degree 270%: 51.2 g.

FIG. 3 shows the relationship between the degree of swelling of the above film in water and the amount of lettuce harvested. FIG. 3 shows that the amount of lettuce harvest increases as the degree of swelling of the film in water increases. In particular, when the degree of swelling in water is 160% or more, the amount of lettuce harvest increases abruptly.

As described above, when using a film with a swelling degree of 270% or less, the roots of the plant could be cultivated without penetrating the film, but when using a film with a swelling degree of 300%, There was a case of penetrating the film.

From the above test results, the degree of swelling of the nonporous hydrophilic film in the support for plant cultivation of the present invention in water is preferably 160% to 300%, and more preferably in the range of 180% to 270%. Preferably there is.

Example 2 In a simple house, a 50 μm thick polyethylene film (Okura Industry Co., Ltd.) having a width of 1 m and a length of 1 m is laid on the soil in the house, and a pumping sheet having a width of 60 cm and a length of 1 m is placed thereon. (SR-130, Meviol Co., Ltd.) was installed. On both sides of the pumped sheet, 10 nozzles of an automatic irrigator were placed on the surface of the pumped sheet, and a nonporous hydrophilic film (PVA film having a thickness of 50 μm) containing no plasticizer was placed thereon. On the film, Supermix A (Sakata Seed Co., Ltd.) as a cultivated soil was placed at a depth of 2 cm, and 10 nozzles of an automatic irrigator were installed on the soil. Silver mulch 30 μm (manufactured by Toago Kosan Co., Ltd.) was used as a mulching film, and six X-marked holes were drilled at 15 cm intervals for seedling planting and covered with culture soil. Sunny lettuce wave (Sakata Seed Co., Ltd.) seeds grow to 1 to 2 seedlings in the cell tray, plant in 6 holes on the mulching film, perform initial irrigation and start cultivation did.

Automatic irrigator: Automatic watering timer EY4200-H (Matsushita Electric Works Co., Ltd.) Cultivation method : After seedling planting, the nutrient solution was supplied at a rate of 200 to 300 mL / day from the nozzle of the automatic irrigator to the pumping sheet under the film . The irrigation (nourishment liquid) of the upper part of the film was carried out by using an automatic irrigator together with a comparative control. The amount of irrigation (nourishing solution) in the upper part was about 20 ml per seedling. The cultivation period was one month (June to July) after planting seedlings.

Nutrient solution : EC was 1.2, and Otsuka House No. 1 0.6 g / L and Otsuka House No. 2 0.9 g / L mixed nutrient solution 1 L mixed with Otsuka House No. 5 0.03 g was used. .

2) Test results The total weight of six seedlings of Komatsuna one month after seedling planting was 143.6 g, and no mold was observed in the nonporous hydrophilic film.

As a comparative control, the same test as in Example 2 was performed except that a nonporous hydrophilic film (50 μm thick PVA film) containing 10% glycerin as a plasticizer was used. Many black molds were observed on the surface of the porous hydrophilic film.

According to the present invention, since the non-porous hydrophilic film that is integrated with the plant root and constitutes the plant cultivation device does not contain a plasticizer, the occurrence of mold that becomes a problem during plant cultivation is suppressed. Can be prevented from being contaminated with mold. Moreover, the favorable growth rate of a plant can be obtained by setting the degree of swelling of the film in water within an appropriate range.

These are vertical cross-sectional views showing examples of basic aspects of the plant cultivation instrument of the present invention. These are vertical cross-sectional views showing examples of other embodiments of the plant cultivation instrument of the present invention. These are graphs showing the relationship between the amount of lettuce harvested by the plant cultivation method of the present invention and the degree of film swelling.

DESCRIPTION OF SYMBOLS 1 Nonporous hydrophilic film 2 Container 3 Nutrient solution 4 Support body for plant cultivation (soil) 5 Evaporation suppression member 6 Means for atomizing spray 7 Plant body 8 Root

Claims (2)

In a plant cultivation device for supplying water or nutrient solution to the lower surface side of a nonporous hydrophilic film that can be substantially integrated with the roots of a plant body and cultivating plants on the film, the nonporous hydrophilic film is provided. Does not contain a plasticizer and has a swelling degree of 160% to 300%. A plant cultivation method using the plant cultivation instrument according to claim 1.