JP7079438B2 - Seedling raising materials, seedling raising tools, seedling raising units and seedling production methods - Google Patents

Description

The present invention relates to a seedling raising material, a seedling raising tool, a seedling raising unit, and a method for producing seedlings.

Fruit vegetables such as tomatoes are cultivated year-round, regardless of the season, by house cultivation. In house cultivation, it is common to plant seedlings. The seedlings include plug seedlings (also called cell-molded seedlings) obtained by germination of seeds sown in the nursery in the pot and large seedlings that can be planted by secondary seedlings. There is. Although plug seedlings can also be planted, in the case of house cultivation, they become overgrown after planting, and overgrowth is particularly remarkable when a culture solution is used (hydroponic cultivation). Therefore, in house cultivation, large seedlings obtained by secondary raising seedlings are preferred.

As a method for raising seedlings, for example, Patent Document 1 proposes a completely closed plant cultivation system (hereinafter, simply referred to as a cultivation system) that is separated from an external space by a non-porous hydrophilic film, and a cultivation method using this cultivation system. is doing. In this cultivation system, a non-porous hydrophilic film (hereinafter, simply referred to as a hydrophilic film) constitutes an internal space for accommodating plants such as seedlings. Then, a part of the hydrophilic film on the external space side is brought into contact with water or a solution arranged in the external space. The hydrophilic film is supported by a support frame.

Japanese Unexamined Patent Publication No. 2009-072075

The production method of large seedlings, which undergoes two seedling raising steps of primary seedling raising and secondary seedling raising as described above, prolongs the production period. Prolonging the production period is directly linked to the limitation of the production turnover rate throughout the year, and also increases the risk of diseases during the growing period. Therefore, it is desired to improve the efficiency of raising seedlings into large seedlings.

Further, in the cultivation system of Patent Document 1, since the hydrophilic film is softened by water in the process of raising seedlings to grow large seedlings, the above-mentioned support frame for supporting the hydrophilic film is indispensable. Therefore, both a step of installing the support frame and a step of providing the non-porous hydrophilic film on the installed support frame are necessary. It takes time and effort to install the support member such as the support frame itself, and the larger the assumed large seedling, the more time and effort it takes. Further, in the cultivation system of Patent Document 1, the hydrophilic film is gradually deteriorated by water in the process of raising seedlings to large seedlings, and as a result, it may be torn by contact with leaves or the like.

Therefore, an object of the present invention is to provide a seedling raising material, a seedling raising tool, a seedling raising unit, and a seedling production method that can be easily installed and improve the seedling raising efficiency for large seedlings.

In order to solve the above problems, the seedling raising material of the present invention contains cellulose acylate, is tubular, is provided in an upright posture with respect to the nursery, and has a hollow portion inside to allow seedlings from the nursery to pass through. When the equivalent circle diameter in the horizontal cross section of the hollow portion is D cm and the height from the nursery is H1 cm, H1 / D is within the range of 0.5 or more and 10.0 or less . , 200 g / m ² · d or more and 1500 g / m ² · d or less .

It is preferable that H1 / D is in the range of 1.0 or more and 8.0 or less. In the seedling raising process, it is preferable to support the seedlings from the surroundings.

It is preferable to form a seedling raising unit together with the nursery and the seedlings, and the seedling raising units are arranged horizontally in the seedling production apparatus. The cellulose acylate preferably has an acyl group substitution degree in the range of 2.00 or more and 2.97 or less .

The height is preferably in the range of 10 cm or more and 50 cm or less. It is preferable that the equivalent circle diameter is within the range of 5 cm or more and 40 cm or less. Cellulose acylate preferably has an acetyl group .

It is preferable that the nursery is provided so as to cover the side surface of the nursery.

The seedling raising tool of the present invention includes a nursery and the above-mentioned seedling raising material.

The seedling raising unit of the present invention includes a seedling and the above-mentioned seedling raising tool.

In the seedling production apparatus, it is preferable to arrange them in the horizontal direction.

The method for producing seedlings of the present invention includes an installation step of providing a tubular seedling raising material in which a hollow portion through which seedlings from the nursery are inserted is formed in an upright position with respect to the nursery, and a seedling raising step. When the seedling raising material contains cellulose acylate, the equivalent circle diameter in the horizontal cross section of the hollow portion is D cm, and the height of the seedling raising material from the nursery is H1 cm, H1 / D is 0. It is in the range of 5 or more and 10.0 or less, and has a water permeability within the range of 200 g / m ² · d or more and 1500 g / m ² · d or less.

In the seedling raising step, it is preferable to grow the seedlings at a height of 50% or more and 150% or less with respect to the height of the seedling raising material from the nursery.

According to the present invention, it can be easily installed and the efficiency of raising seedlings for large seedlings can be improved.

It is a partial cross-sectional schematic diagram of a seedling production apparatus. It is explanatory drawing of the seedling raising tool. It is explanatory drawing of the diameter corresponding to a circle. It is a schematic diagram of the solution film forming apparatus.

The seedling production device 10 shown in FIG. 1 is for producing so-called large seedlings that can be planted by hydroponics, and has a plurality of seedling raising units 12, a chamber (seedling room) 13, a light source unit 16, and a container. 17 and. The seedling raising unit 12 has a seedling raising tool 18 and a seedling 19. The seedling 19 to be grown is a seedling smaller than the plug seedling, and more specifically, the height is 1 cm or more and 8 cm or less, and / or the number of leaves is 2 or more and 5 or less. The seedling 19 is an example of a seedling, and therefore may be a seed (not shown) instead of the seedling 19, and in the case of a seed, the seedling production device 10 performs germination and growth of seedlings (seedling raising). The seedling 19 of this example is a tomato seedling, but the seedling is not limited to tomato, and may be a fruit vegetable seedling other than tomato or a leaf vegetable seedling. Other examples of fruit vegetables include eggplants, peppers, paprika, cucumbers, green soybeans, corn, strawberries and the like. Examples of leafy vegetable seedlings include seedlings of Japanese mustard spinach, cabbage, lettuce, broccoli, celery, spinach, and perilla.

The number of seedling raising units 12 in the seedling production apparatus 10 is not limited to a plurality, and may be one. The plurality of seedling raising units 12 are arranged squarely in the horizontal direction. The number of rows of the seedling raising unit 12 (the number in the left-right direction in FIG. 1) is 6 rows in this example, but is not limited to this example, and may be in the range of 1 row or more and 5 rows or less, or 7 rows. It may be the above. In the figure, an arrow X is attached in the column direction, an arrow Y is attached in the row direction orthogonal to the column direction X in the horizontal direction, and an arrow Z is attached in the vertically upward direction. The number of rows (the number in the row direction Y) of the seedling raising unit 12 is 3 in this embodiment. The number of rows of the seedling raising unit 12 is not limited to this example, and may be within the range of 1 row or more and 2 rows or less, or may be 4 rows or more. The number of rows of the seedling raising unit 12 is preferably in the range of 3 rows or more and 30 rows or less, and more preferably in the range of 5 rows or more and 30 rows or less. The number of rows of the seedling raising unit 12 is preferably in the range of 3 rows or more and 30 rows or less, and more preferably in the range of 5 rows or more and 30 rows or less.

The arrangement mode of the plurality of seedling raising units 12 in the horizontal direction is not limited to the square arrangement, and may be a regular arrangement mode other than the square arrangement or an irregular (random) arrangement. Further, in this example, a plurality of seedling raising units 12 are arranged in a state of being separated from each other with a slight gap, and the distance D1 between the seedling raising units 12 is approximately 5 mm. However, the seedling raising units 12 may be in contact with each other.

The upper part of the container 17 is open and accommodates water 21. The seedling raising tool 18 includes a nursery 22 and a seedling raising material 23, and the nursery 22 is placed in a container 17, whereby at least the lower part of the nursery 22 is immersed in water. By this immersion, water is supplied to the seedling 19. The nursery 22 may be any known material that can be used as a nursery for hydroponics, and may be, for example, soil, sponge, or fibrous material. In this embodiment, rock wool is used as the nursery 22, and specifically, it is a Grodan (registered trademark) rock wool cube manufactured by Rock wool B.V. Holland. The seedling production apparatus 10 is an apparatus for growing seedlings 19 by hydroponics, but the cultivation method by the seedling production apparatus is not limited to hydroponics. Examples of other cultivation methods include soil cultivation, hydroponic cultivation, and elevated cultivation, and the nursery 22 may be changed to one according to the cultivation method.

The seedling raising material 23 is formed in a tubular shape with a sheet, and is provided in an upright posture with respect to the nursery 22 (installation step). Since the seedling raising material 23 has a tubular shape, a hollow portion 23h through which the seedling 19 from the nursery 22 is inserted is formed inside. As a result, since the seedling 19 is supported from the surroundings by the seedling raising material 23 in the seedling raising process, it grows in a manner of extending upward without using, for example, a support other than the seedling raising material 23. Therefore, it grows into a large seedling in one seedling raising process. In this way, since it is not necessary to replant for secondary seedling raising after primary seedling raising, large seedlings are efficiently produced. When seeds are used instead of seedlings 19, they are similarly efficient because they can be grown from germination to large seedlings. Of course, even when the above-mentioned plug seedling obtained in the primary seedling raising is grown as the seedling 19 of this example, the seedling grows in a manner of extending upward without using a support or the like. Further, since the seedling raising material 23 is provided in each of the plurality of nurseries 22, when the seedlings 19 grow into large seedlings, the stems and leaves of the seedlings 19 can be prevented from being entangled with each other. As a result, since it is easy to manage the growth of the plurality of seedlings 19 individually, the seedling raising efficiency is improved, and there is an advantage that the produced large seedlings can be easily handled individually when they are moved to another place.

The seedling raising material 23 is in an upright posture so as to cover the side surface of the nursery 22. This prevents root entanglement in the growing process of the seedling 19. As a result, for example, when the produced large seedlings are moved to another place, there is a convenience that individual handling is easy. In addition, when a disease or the like is confirmed in a specific part of the seedlings 19 in the seedling raising process, it is easy to take out. The seedling raising material 23 in this example is in an upright posture in a state of covering the side surface of the nursery bed 22, but is not limited to the mode of covering the side surface of the nursery bed 22 as long as it is in an upright posture with respect to the nursery bed 22. For example, it may be arranged on the nursery 22. When arranging on the nursery 22, the seedling raising material 23 may be placed on the nursery 22, or the lower part of the seedling raising material 23 may be fixed to the nursery 22 by inserting it into the nursery 22 from above. good.

The seedling raising material 23 has a cylindrical shape with a rectangular cross section in the horizontal direction, and in this example, has a square cross section. The cross-sectional shape of the seedling raising material 23 in the horizontal direction is not limited to this, and may be, for example, a circle (including an ellipse), a polygon other than a rectangle, or an amorphous shape. However, for example, when a plurality of tubular seedling raising materials 23 having the same size are arranged, the seedling production apparatus 10 is arranged in the most dense state by making the cross-sectional shape in the horizontal direction square, that is, tessellation is performed. Can be done. This is more preferable because more seedlings 19 can be produced within a limited installation area. Further, even when the produced seedlings are stored in the state of the seedling raising unit 12, delivered, or arranged in a store, they can be arranged in a tessellation in a limited installation place. For example, from the viewpoint of arranging a plurality of seedling raising materials having the same size and shape in a plane-oriented manner, the shape in the horizontal direction is not limited to a square, and may be an equilateral triangle or a regular hexagon.

The seedling raising material 23 is formed by forming a cellulose acylate film in a tubular shape, that is, contains (contains) cellulose acylate. In this example, the seedling raising material 23 is formed by folding the cellulose acylate film into a cylinder having a square cross section and fixing one end and the other end of the folded cellulose acylate film with an adhesive tape. Is not limited to this. For example, one end and the other end of the folded cellulose acylate film may be fixed by heat sealing. Further, the seedling raising material 23 may be formed by preparing four rectangular cellulose acylate films and fixing the cellulose acylate films in the longitudinal direction to each other.

Since the seedling raising material 23 is formed of cellulose acylate, it has high transparency, and the light from the light source 26 described later is effectively irradiated to the seedling 12 and / or the nursery 22. Further, since the cellulose acylate film has an appropriate hardness, it can easily stand on its own by forming it into a cylindrical shape without using a support member such as a support frame, so that the seedling raising material 23 can be easily installed. Further, since the seedling raising material 23 contains cellulose acylate, the equilibrium water content increases due to the increase in humidity in the hollow portion 23h due to the water content during seedling raising. Due to this increase in the equilibrium water content, the seedling raising material 23 absorbs water. Moisture in the hollow portion 23h decreases due to absorption of water in the seedling raising material, whereby the equilibrium water content of the seedling raising material 23 decreases and water is released. In this way, the humidity in the hollow portion 23h is suppressed from changing. As a result, (1) dew condensation on the inner wall 23i (see FIG. 2) of the seedling raising material 23 is suppressed, (2) the growth and growth of mold and pathogens on the seedling 19 and / or the nursery 22 are suppressed, and (3) seedlings. There are effects such as suppression of excessive growth and / or overgrowth of 19; (4) suppression of discoloration of leaves of seedling 19 and (5) reliable maintenance of opening / closing mechanism of pores of leaves of seedling 19. can get. Further, since the increase in humidity of the hollow portion 23h is suppressed, the seedling raising material 23 is suppressed from being deformed by water absorption, and as a result, the standing posture is maintained for a long period of time when the seedling 19 grows into a large seedling. Therefore, even a small seedling 19 that has just been germinated can be used continuously for a period of growing a large seedling by raising the seedling once. Alternatively, it can be used continuously even when raising seedlings from seed germination to large seedlings. Of course, it can also be used for secondary seedling raising when the primary seedling raising and the secondary seedling raising are performed twice.

The above equilibrium water content is the equilibrium water content at 25 ° C. and a relative humidity of 80%. This temperature and relative humidity correspond to the temperature and relative humidity set as the seedling raising environment.

Cellulose acylate has an acyl group because the hydroxy group of cellulose is esterified with a carboxylic acid. The degree of acyl group substitution of the cellulose acylate contained in the seedling raising material 23 is preferably in the range of 2.00 or more and 2.97 or less. As a result, the humidity change of the hollow portion 23h can be suppressed to be smaller. The smaller the degree of acyl group substitution, the higher the amount of water absorbed by the seedling raising material 23, so that it is easily deformed by water absorption. However, by setting the degree of acyl group substitution of the cellulose acylate constituting the seedling raising material 23 to 2.00 or more. Deformation is more reliably suppressed, which is preferable. The theoretical upper limit of the degree of acyl group substitution is 3.00, but it is difficult to synthesize cellulose acylate having an acyl group substitution degree of more than 2.97. Therefore, the degree of acyl group substitution of the cellulose acylate constituting the seedling raising material 23 is set to 2.97 or less.

The degree of acyl group substitution of the cellulose acylate contained in the seedling raising material 23 is more preferably in the range of 2.40 or more and 2.95 or less, and further preferably in the range of 2.70 or more and 2.95 or less. As is well known, the degree of acyl group substitution is the rate at which the hydroxy group of cellulose is esterified with a carboxylic acid, that is, the degree of substitution of the acyl group.

The acyl group of the cellulose acylate constituting the seedling raising material 23 is not particularly limited, and may be an acetyl group having 1 carbon atom or an acyl group having 2 or more carbon atoms. The acyl group having 2 or more carbon atoms may be an aliphatic group or an aryl group, and examples thereof include an alkylcarbonyl ester of cellulose, an alkenylcarbonyl ester or an aromatic carbonyl ester, and an aromatic alkylcarbonyl ester. It may further have a substituted group. Propionyl group, butanoyl group, pentanoyl group, hexanoyl group, octanoyl group, decanoyl group, dodecanoyl group, tridecanoyl group, tetradecanoyl group, hexadecanoyl group, octadecanoyl group, iso-butanoyl group, t-butanoyl group, cyclohexane Examples thereof include a carbonyl group, an oleoyl group, a benzoyl group, a naphthylcarbonyl group, a cinnamoyl group and the like.

The acyl group of the cellulose acylate constituting the seedling raising material 23 may be only one kind or two or more kinds, but it is preferable that at least one kind is an acetyl group. Since the seedling raising material 23 easily absorbs water due to the cellulose acylate having an acetyl group, the effect of suppressing the change in humidity in the hollow portion 23h is further improved. Most preferably, it is a cellulose acylate in which all the acyl groups are acetyl groups, that is, it is more preferable that the cellulose acylate is cellulose acetate.

The degree of acyl group substitution can be determined by a conventional method. For example, the degree of acetylation (degree of acetyl group substitution) is determined according to the measurement and calculation of the degree of acetylation in ASTM: D-817-91 (test method such as cellulose acetate). It can also be measured by measuring the degree of acylation (degree of acyl group substitution) distribution by high performance liquid chromatography. As an example of this method, in the measurement of the degree of acetylation of cellulose acetate, a sample is dissolved in methylene chloride, a column Novapac phenyl (Waters) is used, and a mixed solution of methanol and water as an eluent (methanol: water mass ratio is The degree of acetylation distribution was measured by linear gradient from 8: 1) to a mixed solution of dichloromethane and methanol (dichloromethane: methanol mass ratio of 9: 1), and compared with the calibration line using standard samples with different degrees of acetylation. Ask for. These measuring methods can be obtained by referring to the methods described in JP-A-2003-201301. When the seedling raising material 23 contains an additive, the measurement of the degree of acetylation of the cellulose acylate is preferably performed by high performance liquid chromatography.

The seedling raising material 23 may contain an additive. There is a plasticizer as an additive, and this example also contains a plasticizer. As the plasticizer, various known plasticizers can be used. For example, triphenyl acetate (TPP), biphenyl diphenyl phosphate (BDP), an ester derivative of a sugar, an ester oligomer and the like can be mentioned, and the seedling raising material 23 of this example contains (contains) an ester derivative or an ester oligomer of a sugar. do). The seedling raising material 23 may contain, as an additive, an ultraviolet absorber, fine particles as a so-called matting agent for preventing the seedling raising materials 23 from sticking to each other, and the like, in addition to the plasticizer.

The seedling raising material 23 preferably has a moisture permeability within the range of 200 g / m ² · d or more and 1500 g / m ² · d or less. When the moisture permeability is 200 g / m ² · d or more, a large increase in the humidity of the hollow portion 23h during raising seedlings is more reliably suppressed as compared with the case where it is less than 200 g / m ² · d. When the moisture permeability is 1500 g / m ² · d or less, the standing posture is maintained for a longer period of time as compared with the case where the moisture permeability exceeds 1500 g / m ² · d. The water permeability is more preferably in the range of 300 m ² · d or more and 1300 g / m ² · d or less, and further preferably in the range of 400 m ² · d or more and 1200 g / m ² · d or less.

Methods for increasing the moisture permeability to 200 g / m ² · d or more include using an ester derivative and / or an ester oligomer of sugar as a plasticizer, reducing the amount of the plasticizer, and reducing the thickness to 200 μm or less. .. Further, as a method for reducing the moisture permeability to 1500 g / m ² · d or less, increasing the amount of the plasticizer and increasing the thickness to 40 μm or more can be mentioned.

The light source unit 16 is for irradiating the nursery 22 and / or the seedling 19 with light. Before germination in the case of germination from seeds, the light source unit 16 is for irradiating the nursery 22 with light. The light source unit 16 includes a plurality of light sources 26 that emit light, a support plate 27, and a controller 28. The support plate 27 is an example of a support member that supports a plurality of light sources 26. In this example, each light source 26 is provided on a lower surface which is a facing surface facing the plurality of seedling raising units 12. The controller 28 has a first function of adjusting the amount of light emitted from each of the plurality of light sources 26 and a second function of controlling the on / off of each of the plurality of light sources 26. The first function adjusts the amount of light applied to the seedling 19 or the nursery 22. The second function adjusts the timing and duration of light irradiation according to the type and / or degree of growth of the seedling 19. In this way, the light source 26 irradiates the seedling 19 or the nursery 22 with the light controlled by the controller 28. As a result, the seedling 19 grows, and in the case of a seed, it germinates. The distance of the light source 26 from the seedling raising unit 12 is approximately 100 mm in this example, but the distance is not limited to this example.

The chamber 13 accommodates the seedling raising unit 12, the light source 26 of the light source unit 16, the support plate 27, and the container 17, and has a temperature / humidity controller 31. The temperature / humidity controller 31 adjusts the growth environment of the seedlings 19 by adjusting the temperature and humidity inside the chamber 13. The temperature inside the chamber 13 is not particularly limited, but is preferably in the range of 10 ° C. or higher and 40 ° C. or lower. In this example, the temperature is set to 20 ° C, and it is confirmed that the temperature fluctuates in the range of 17.5 ° C or higher and 22.5 ° C or lower. The humidity inside the chamber 13 is not particularly limited, but is preferably a relative humidity in the range of 50% or more and 80% or less. In this example, it is kept within the range of 40.5% or more and 91% or less. When the seedling raising unit 12 is provided outdoors without a roof without using the chamber 13, the upper member 23t made of the same material as or different from the seedling raising material 23 is placed on the seedling raising material 23 (FIG. 2) may be provided.

The seedling 19 is grown by supplying water 21 to the seedling 19, irradiating it with light, and controlling the temperature and humidity (seedling raising step). Since the above-mentioned seedling raising material 23 is used in the seedling raising method of this example, the seedling 19 grows into a large seedling in one seedling raising step.

The seedling raising tool 18 will be described in more detail with reference to FIG. 2. The diameter corresponding to the circle in the horizontal cross section of the hollow portion 23h is D cm, and the height from the nursery 22 is H1 cm. In the material 23, H1 / D obtained by dividing the height H1 cm by the circle equivalent diameter Dcm is preferably in the range of 0.5 or more and 10.0 or less, and in this example, it is set to 3.5, for example. When H1 / D is 0.5 or more, it is more certain that the seedling 19 grows higher in an upright posture than when it is less than 0.5. Further, when H1 / D is 10.0 or less, the standing posture of the seedling raising material 23 is more reliably maintained during the seedling raising period. H1 / D is more preferably in the range of 1.0 or more and 8.0 or less, and further preferably in the range of 1.5 or more and 6.0 or less. The circle equivalent diameter D (unit: cm) is the diameter of the circle C when a circle C having the same area as the area of the hollow portion 23h surrounded by the seedling raising material 23 shown in FIG. 2 (B) is drawn. Yes (see Figure 3).

When H1 / D is in the range of 0.5 or more and 10.0 or less, the height H1 (unit; cm) is preferably in the range of 10 cm or more and 70 cm or less, and in this example, it is set to, for example, 30 cm. .. When the height H1 is 10 cm or more, it is more certain that the seedling 19 grows high in an upright posture. When the height H1 is 70 cm or less, the upright posture of the seedling raising material 23 is more reliably maintained during the seedling raising period. The height H1 is more preferably in the range of 15 cm or more and 50 cm or less, and further preferably in the range of 20 cm or more and 40 cm or less.

When H1 / D is in the range of 0.5 or more and 10.0 or less, the equivalent circle diameter D is preferably in the range of 5 cm or more and 40 cm or less, and in this example, it is set to 8.5 cm, for example. When the circle equivalent diameter D is 5 cm or more, the standing posture of the seedling raising material 23 is more reliably maintained during the seedling raising period as compared with the case where it is less than 5 cm. Since the area equivalent to the circle D is 40 cm or less, the area occupied by the seedling raising material 23 and the seedling raising unit 12 can be reduced, so that a large seedling with a target planting number can be reliably secured. The equivalent circle diameter D is more preferably in the range of 7 cm or more and 30 cm or less, and further preferably in the range of 8 cm or more and 20 cm or less.

The thickness T of the seedling raising material 23 is preferably in the range of 20 μm or more and 200 μm or less, and is 100 μm in this example. When the thickness is 20 μm or more, the installation becomes easier as compared with the case where the thickness is less than 20 μm, and the standing posture is more reliably maintained during the growing period of the large seedling. Since the thickness T is 200 μm or less, it is easier to bend the seedling raising material 23 when it is formed into a tubular shape, and it is less likely to break when it is bent, as compared with the case where it is larger than 200 μm. The thickness T is more preferably 30 μm or more and 150 μm or less, and particularly preferably 40 μm or more and 130 μm or less.

The T / H1 obtained by dividing the thickness T (unit: μm) by the height H1 is preferably in the range of 5.0 × 10 ^-5 or more and 2.0 × 10 ^-3 or less. Since the T / H1 is 5.0 × ^10-5 or more, it is easier to install in an upright posture than in the case of less than 5.0 × ^10-5 , and the seedling raising material 23 in the process of growing into a large seedling. It spreads moderately according to the spread of the upper leaves, but the standing posture is more reliably maintained during the growing period. When T / H1 is 2.0 × 10 ^-3 or less, the seedling raising material 23 suppresses the spread of the upper leaves too much in the process of growing large seedlings, as compared with the case where it is larger than 2.0 × 10 ^-3 . Therefore, better quality large seedlings with moderately spread upper leaves are obtained.

In the seedling raising step, it is preferable to grow the seedlings 19 at a height of 50% or more and 150% or less with respect to the height H1, and in this example, the seedlings are grown at a height of 130%. The height of the seedling is the height from the nursery 22 and is designated by the reference numeral H2 in FIG. By growing the seedling 19 at a height of 50% or more with respect to the height H1, the growth to a large seedling suitable for planting becomes more reliable. By growing the seedlings 19 at a height of 150% or less with respect to the height H, the entanglement of the leaves between the seedlings 19 and the sagging of the leaves above the seedlings 19 and / / Or, the fall is suppressed, and as a result, a large seedling that can be transplanted more easily and has good quality can be obtained.

When the seedling 19 was grown using the seedling raising material 23 having the above configuration, the following was compared with the case where the seedling 19 was grown using the seedling raising material formed of a polyethylene terephthalate (hereinafter referred to as PET) film. The result of is obtained. The seedling raising material formed of the PET film has the same shape and size as the seedling raising material 23. In addition, the following SPAD value "SPAD" is an abbreviation for the large-scale management soil / crop / product analysis system practical application project of the Agriculture and Horticulture Bureau, Ministry of Agriculture, Forestry and Fisheries, and the SPAD value is the amount of chlorophyll developed by SPAD. It is an index. The SPAD value is measured at the tip of the largest leaf (largest leaf) among the plurality of leaves of the obtained seedling 19. In addition, the number of roots below counts the number of adventitious roots generated on the surface of rock wool as a nursery 22. Adventitious roots are root legginess that occur when taproots are poorly developed and occur when the surface is over-humidified.

(1) The maximum leaf length (the longest leaf length among a plurality of leaves) in the obtained seedlings is 32.3 cm, which is longer than 29.3 cm when the seedling raising material formed of PET film is used. Yes, there is a significant difference. That is, the growth of individual leaves is good and better.

(2) The SPAD value was 47.6, which was higher than 37.5 when the seedling raising material formed of PET film was used, as measured by the chlorophyll meter SPAD-502Plus manufactured by Konica Minolta Co., Ltd., which is significant. There is a difference. That is, it has more chlorophyll and is better.

(3) The number of roots is 8.0, which is significantly different from that of 28.2 roots when the seedling raising material formed of PET film is used. That is, it shows that the medium surface was maintained to the extent that it did not become excessively humid without having too many adventitious roots, which was better.

The solution film forming apparatus 50 of FIG. 4 continuously produces the cellulose acylate film 51 from the dope 52 by the solution film forming method. The long cellulose acylate film 51 is cut into a sheet shape and formed into a tubular shape to obtain a seedling raising material 23. Dope 52 is a cellulose acylate solution in which cellulose acylate having an acyl group substitution degree within the above range is dissolved in a solvent. In this embodiment, a mixture of dichloromethane and methanol is used as the solvent, but the solvent is not limited thereto. The dope 52 may contain the above-mentioned various additives, and the dope 52 of the present embodiment contains a plasticizer and a matting agent.

The solution film forming apparatus 50 includes a casting unit 55, a roller dryer 56, and a winder 57 in order from the upstream side. The flow unit 55 includes a belt 61 formed in an annular shape, a pair of rollers 62 that run the belt 61 in the longitudinal direction while being supported by the peripheral surface, a blower 63, a flow die 64, and a stripping roller 65. And. At least one of the pair of rollers 62 rotates in the circumferential direction, and this rotation causes the wound belt 61 to continuously travel in the longitudinal direction. Although the casting die 64 is arranged above one of the pair of rollers 62 in this example, it may be arranged above the belt 61 between one and the other of the pair of rollers 62.

The belt 61 is a support for the cast film 66 described later, and is, for example, a length of 55 m or more and 200 m or less, a width of 150 cm or more and 500 cm or less, and a thickness of 1.0 mm or more and 2.0 mm or less. It is inside.

The flow die 64 continuously flows out the supplied dope 52 from the outlet 64a facing the belt 61. By continuously flowing out the dope 52 to the running belt 61, the dope 52 is spread on the belt 61, and the casting film 66 is formed on the belt 61.

The pair of rollers 62 includes a temperature controller (not shown) that adjusts the peripheral surface temperature. The temperature of the cast film 66 is adjusted via the belt 61 by the roller 62 whose peripheral surface temperature is adjusted. In the case of the so-called dry gelling method in which the cast film 66 is heated and hardened (gelled) by accelerating drying, the peripheral surface temperature of the roller 62 is set to be in the range of, for example, 15 ° C. or higher and 35 ° C. or lower. good. Further, in the case of the so-called cooling gelling method in which the cast film 66 is cooled and hardened, the peripheral surface temperature of the roller 62 may be set within the range of −15 ° C. or higher and 5 ° C. or lower. In this embodiment, a dry gelation method is used.

The blower 63 is for drying the formed flow film 66. The blower 63 is provided so as to face the belt 61. The blower 63 promotes the drying of the flow film 66 by sending a gas to the flow film 66. In the present embodiment, the gas to be sent is air heated to 100 ° C., but the temperature is not limited to 100 ° C., and the gas is not limited to air. Drying by the blower 63 causes the flow film 66 to gel more quickly. Then, the casting film 66 is made hard enough to be conveyed by gelation.

With respect to the dope 52 from the flow die 64 to the belt 61, the so-called bead, a decompression chamber (not shown) may be provided upstream of the belt 61 in the traveling direction. This decompression chamber sucks the atmosphere of the upstream area of the outflowing dope 52 and decompresses this area.

The cast film 66 is hardened on the belt 61 to the extent that it can be conveyed by the roller dryer 56, and then peeled off from the belt 61 in a state containing a solvent. The stripping roller 65 is for continuously stripping the cast film 66 from the belt 61. The stripping roller 65 supports the cellulose acylate film 51 formed by stripping from the belt 61, for example, from below, and holds the stripping position PP in which the cast film 66 is peeled off from the belt 61 at a constant level. The stripping method may be either a method of pulling the blue cellulose acylate film 51 to the downstream side, a method of rotating the stripping roller 65 in the circumferential direction, or the like.

In the case of the dry gelation method, the stripping from the belt 61 is performed, for example, while the solvent content of the cast film 66 is in the range of 3% by mass or more and 100% by mass or less, and is 100 in the present embodiment. It is done by mass%. In the case of the cooling gelling method, for example, it is preferable to carry out the method while the solvent content of the cast film 66 is in the range of 100% by mass or more and 300% by mass or less. In the present specification, the solvent content (unit;%) is a value based on the dry amount, specifically, the mass of the solvent is x, and the mass of the cellulose acylate film 51 for which the solvent content is obtained is y. Then, it is a percentage obtained by {x / (y−x)} × 100.

As described above, the casting unit 55 forms the cellulose acylate film 51 from the dope 52. As the belt 61 circulates and travels, the dope 52 is cast and the cast film 66 is peeled off repeatedly.

The roller dryer 56 is for drying the formed cellulose acylate film 51, and includes a plurality of rollers 73 and an air conditioner (not shown). Each roller 73 supports the cellulose acylate film 51 on the peripheral surface. The cellulose acylate film 51 is wound around a roller 73 and conveyed. The air conditioner adjusts the temperature, humidity, and the like inside the roller dryer 56. In the roller dryer 56, the cellulose acylate film 51 is recommended to be dried while being supported and conveyed by each roller 73. The winder 57 is for winding a long cellulose acylate film 51, and the cellulose acylate film 51 is wound into a roll by the winder 57. A tenter (not shown) for stretching the cellulose acylate film 51 in the width direction may be provided between the casting unit 55 and the roller dryer 56. Further, a slitter (not shown) may be provided between, for example, the roller dryer 56 and the winder 57, and each side portion of the cellulose acylate film 51 may be continuously cut off by this slitter. The seedling raising material 23 is manufactured by cutting the cellulose acylate film 51 into a rectangular shape and then forming it into a tubular shape as described above.

Hereinafter, examples of the present invention and comparative examples with respect to the present invention will be given.

[Example 1] to [Example 22]
A cellulose acylate film 51 having a width of 1340 cm was produced by a solution film forming apparatus 50, and a length of 2000 m was wound by a winder 57. The seedling raising material 23 was produced from each cellulose acylate film 51 by the above-mentioned method, and 18 seedling raising units 12 using each seedling raising material 23 were prepared. Tomato seedlings 19 were grown by each seedling raising unit 12 and used as Examples 1 to 11.

The prescription of Dope 52 is as follows. The following solid content is a solid component constituting the cellulose acylate film 51.

1st component of solid content 100 parts by mass 2nd component of solid content 2nd component of solid content Mass part shown in the "Amount" column of Table 1 3rd component of solid content 1.3 parts by mass dichloromethane (1st component of solvent) 635 parts by mass Methanol ( (Second component of solvent) 125 parts by mass The first component of the solid content is cellulose acylate, and in Table 1, "cellulose acylate" is described in the "substance" column of "first component". In this cellulose acylate, all the acyl groups are acetyl groups, and the viscosity average degree of polymerization is 320.

The second component of the solid content was A or B shown in the "second component" column of Table 1. A is an ester derivative of sugar, and specifically, is a benzoic acid ester of sucrose (Monopet SB manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.). B is an ester oligomer, specifically, an oligomer having an ester of adipic acid and ethylene glycol as a repeating unit (the number average molecular weight by the terminal functional group quantification method is 1000). The "second component amount" in Table 1 is the mass of the second component when the mass of the cellulose acylate is 100, and the "PHR" in Table 1 is an abbreviation for perhand red resin and means the mass part. be. The third component of the solid content is silica fine particles, which is R972 manufactured by Nippon Aerosil Co., Ltd.

The dope 52 was made by the following method. First, the first component of the solid content, the second component, and the solvent which is a mixture of dichloromethane and methanol are each put into a closed container, and the mixture is stirred in the closed container while maintaining the temperature at 40 ° C. , The first component and the second component of the solid content were dissolved in a solvent. The third component of the solid content is dispersed in a mixture of dichloromethane and methanol, and the obtained dispersion is placed in the above-mentioned closed container containing a solution in which the first component and the second component of the solid content are dissolved. Dispersed. The dope 52 thus obtained is allowed to stand, filtered through a filter paper while maintaining the temperature at 30 ° C., defoamed, and then cast in a solution film forming apparatus 50. Served.

A dope 52 at 30 ° C. was cast from the casting die 64 to form a casting film 66. Air at 100 ° C. was applied to the cast film 66 immediately after formation by a blower 63, and the dried cast film 66 was stripped from the belt 61 by a stripping roller 65. The temperature of the belt 61 at the stripping position PP was 10 ° C. The flow film 66 was peeled off 120 seconds after it was formed. The solvent content of the cast film 66 at the stripping position PP was 100% by mass. The stripping was performed with a tension of 150 N / m. This tension is the force per 1 m of width of the flow film 66. The formed cellulose acylate film 51 was guided to a roller dryer 56 and dried while being conveyed in a state where tension was applied in the longitudinal direction by a plurality of rollers 73. The tension applied in the longitudinal direction was 100 N / m. This tension is the force per 1 m of width of the cellulose acylate film 51. The roller dryer 56 has a first zone on the upstream side and a second zone on the downstream side, and the first zone is set to 80 ° C. and the second zone is set to 120 ° C. The cellulose acylate film 51 was transported in the first zone for 5 minutes and in the second zone for 10 minutes. The solvent content of the cellulose acylate film 51 wound by the winder 57 was 0.3% by mass.

For the seedling raising material 23 produced from each cellulose acylate film 51, the degree of acyl group substitution of cellulose acylate is shown in the “Acyl group substitution degree” column of Table 1. The thickness T of the seedling raising material 23 is shown in the "thickness" column of the "seedling raising material", and the height H1 is shown in the "height" column. In Table 1, the numerical value following "E" in the "T / H1" column indicates a power of 10. For example, "3.3E-04" means ^3.3-4 .

In Examples 1 to 21, the cell tray for sowing was filled with seed culture soil, and Momotaro York (manufactured by Takii Seed Co., Ltd.) was sown and germinated by growing for 16 days. It was transplanted to the nursery 22. Eighteen seedling raising units 12 using the seedling raising material 23 were placed side by side in one chamber 13, and each seedling 19 was grown for 14 days in that state.

In Example 22, the above-mentioned Momotaro yoke was sown in each nursery 22 of the 18 seedling raising tools 18, and 18 seedling raising units 12 were installed side by side in one chamber 13. In that state, germination and raising seedlings were carried out. The growing period was 30 days. Other conditions of Example 22 are the same as those of Example 1.

The maintenance of the standing posture of each seedling raising material 23, the height of the produced seedling 19, the ease of transplanting the produced seedling 19, and the quality of the produced seedling 19 were evaluated. The evaluation methods and evaluation criteria are as follows, and the evaluation results are shown in Table 1.

1. 1. Maintaining the standing posture When the standing posture of the seedling raising material 23 is maintained during the growing period of the seedling 19, the seedling 19 can be grown upward and even a large seedling can be grown. Therefore, the maintenance of the standing posture of the seedling raising material 23 was visually observed and evaluated based on the following criteria. A to C are those in which the standing posture was maintained during the above-mentioned seedling raising period, and passed. D fails.

A: No change was confirmed at the end of seedling raising from the time of installation. B; At the end of seedling raising, wrinkles and / or deformation were observed very slightly, but the standing posture was maintained and the seedlings could be reused.

C; At the end of raising seedlings, wrinkles and / or deformation were observed, and although they could not be reused, the standing posture was maintained.

D; Wrinkles and deformation were observed during the seedling raising process, and it became impossible to stand on its own during the seedling raising process.

2. 2. Height of seedlings produced The height of seedlings 19 was measured at the end of seedling raising. Each result is described in the "seedling height" column of Table 1 in cm. The heights of the seedlings shown in Table 1 were measured by measuring the individual heights of the 18 seedlings 19 raised for each example, and used as the average value of these heights. When the height was 15 cm or more, it was said that the seedlings had grown into large seedlings that could be planted, and the seedlings were accepted. When the height is 25 cm or more, it is particularly suitable for planting. If the height did not reach 15 cm, it could be said that secondary seedling raising was necessary before planting in order to plant, and the production efficiency was poor, so it was rejected.

3. 3. Ease of transplanting seedlings After the seedlings were raised, the obtained seedlings 19 were evaluated according to the following criteria in the work of subjecting them to planting. P is a pass and F is a failure.

P; Adjacent seedlings 19 did not get entangled with each other, and it was easy to handle a plurality of seedlings 19 individually.

F; Adjacent seedlings 19 were entangled with each other, and it took time to handle a plurality of seedlings 19 individually.

4. Quality of seedlings The seedlings obtained by growth were planted in this field, and the aspect after planting was visually observed, and the evaluation based on the following criteria was carried out as the quality evaluation of the seedlings. In Table 1, A to C are pass and D is fail.

A: There are many leaves from the top of the seedlings, and the stems are firm and self-supporting.

B; Leaves hang down slightly from the top to the bottom of the seedlings, but they generally stand on their own without support.

C; The leaves of the seedlings hung down, and the middle to upper part of the stem was bent downward.

D; Seedlings collapse or cannot stand on their own. In particular, yellowing of the lower leaves is seen.

［比較例１］，［比較例２］
育苗資材２３を使用しないこと以外は実施例１と同じ条件で育苗し、比較例１とした。比較例１は、育苗資材２３を使用していないから、表１の「育苗資材」の各欄のうち、「有無」欄を除く欄は、「－」と記載している。比較例２は、ポリエチレンテレフタレート（以下、ＰＥＴと称する）フィルムを育苗資材２３と同様の筒状に形成し、これを育苗資材として用い、実施例１と同じ条件で育苗した。用いたＰＥＴフィルムは、東レ株式会社製のルミラー（登録商標）Ｔ６０＃１００（厚みは１００μｍ）である。

[Comparative Example 1], [Comparative Example 2]
The seedlings were raised under the same conditions as in Example 1 except that the seedling raising material 23 was not used, and the seedlings were used as Comparative Example 1. Since the seedling raising material 23 is not used in Comparative Example 1, the columns other than the “presence / absence” column in each column of “seedling raising material” in Table 1 are described as “−”. In Comparative Example 2, a polyethylene terephthalate (hereinafter referred to as PET) film was formed into a tubular shape similar to that of the seedling raising material 23, and this was used as the seedling raising material to raise seedlings under the same conditions as in Example 1. The PET film used was Lumirror (registered trademark) T60 # 100 (thickness 100 μm) manufactured by Toray Industries, Inc.

By the same method and criteria as in the examples, the standing posture of the seedling raising material was maintained, the height of the seedlings obtained by growing, the ease of transplanting the obtained seedlings, and the quality of the obtained seedlings after planting. Was evaluated. In Comparative Example 1, since the seedling raising material was not used, the maintenance of the standing posture of the seedling raising material was not evaluated. Therefore, in the "Maintenance of standing posture" column of Table 1, "-" which means that the evaluation is not performed is described. The evaluation results are shown in Table 1.

10 Seedling production equipment 12 Seedling raising unit 13 Chamber 16 Light source unit 17 Container 18 Seedling tool 19 Seedling 21 Water 22 Seedbed 23 Seedling material 23h Hollow part 23i Inner wall 23t Upper member 26 Light source 27 Support plate 28 Controller 31 Temperature and humidity controller 50 Solution film forming Equipment 51 Cellulose acylate film 52 Dope 55 Spreading unit 56 Roller dryer 57 Winder 61 Belt 62 Roller 63 Blower 64 Flowing die 64a Outlet 65 Stripping roller 66 Rolling film 73 Roller C circle D circle equivalent diameter D1 Distance H1 Height of seedling raising material from nursery H2 Height of seedling PP Peeling position T Thickness X Column direction Y Row direction Z Vertical upward direction

Claims (14)

Contains cellulose acylate,
It is tubular and is provided in an upright position with respect to the nursery, and a hollow portion through which seedlings from the nursery are inserted is formed inside.
When the equivalent circle diameter in the horizontal cross section of the hollow portion is D cm and the height from the nursery is H1 cm, H1 / D is in the range of 0.5 or more and 10.0 or less .
A seedling raising material having a moisture permeability within the range of 200 g / m ² · d or more and 1500 g / m ² · d or less. The seedling raising material according to claim 1, wherein H1 / D is in the range of 1.0 or more and 8.0 or less. The seedling raising material according to claim 1 or 2, which supports the seedlings from the surroundings in the seedling raising process. A seedling raising unit was formed with the nursery and the seedlings,
The seedling raising material according to any one of claims 1 to 3, wherein the seedling raising unit is arranged in a horizontal direction in a seedling production apparatus. The seedling raising material according to any one of claims 1 to 4, wherein the cellulose acylate has an acyl group substitution degree in the range of 2.00 or more and 2.97 or less. The seedling raising material according to any one of claims 1 to 5, wherein the height is within the range of 10 cm or more and 50 cm or less. The seedling raising material according to any one of claims 1 to 6, wherein the equivalent circle diameter is within the range of 5 cm or more and 40 cm or less. The seedling raising material according to any one of claims 1 to 7, wherein the cellulose acylate has an acetyl group. The seedling raising material according to any one of claims 1 to 8 , which is provided so as to cover the side surface of the nursery. The nursery and
The seedling raising material according to any one of claims 1 to 9 and
A nursery tool equipped with. Seedlings and
The seedling raising tool according to claim 10 and
A nursery unit equipped with. The seedling raising unit according to claim 11 , which is arranged in the horizontal direction in the seedling production apparatus. An installation process in which a tubular seedling raising material having a hollow portion through which seedlings from the nursery are inserted is provided in an upright posture with respect to the nursery.
Seedling process and
Have,
The seedling raising material contains cellulose acylate and contains
When the equivalent circle diameter in the horizontal cross section of the hollow portion is D cm and the height of the seedling raising material from the nursery is H1 cm, H1 / D is within the range of 0.5 or more and 10.0 or less. Yes,
A method for producing seedlings having a moisture permeability within the range of 200 g / m ² · d or more and 1500 g / m ² · d or less. The method for producing seedlings according to claim 13 , wherein the seedling raising step is to grow the seedlings at a height of 50% or more and 150% or less with respect to the height of the seedling raising material from the nursery.

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