CN111065260B

CN111065260B - Seedling raising material, seedling raising tool, seedling raising unit and seedling production method

Info

Publication number: CN111065260B
Application number: CN201880056061.6A
Authority: CN
Inventors: 鹫谷公人; 中野明正
Original assignee: Fujifilm Corp
Current assignee: Fujifilm Corp
Priority date: 2017-08-29
Filing date: 2018-08-27
Publication date: 2022-09-09
Anticipated expiration: 2038-08-27
Also published as: JP7079438B2; CN111065260A; WO2019044760A1; JP2019041587A

Abstract

The invention provides a seedling raising material, a seedling raising tool, a seedling raising unit and a seedling production method, which can be simply arranged and improve the seedling raising efficiency of grown seedlings. The seedling raising unit (12) is provided with a seedling raising tool (18) and seedlings (19). The seedling raising tool (18) has a seedling raising material (23) and a seedbed (22). The seedling raising material (23) contains cellulose acylate having an acyl group. The seedling raising material (23) is cylindrical and is set in a standing posture with respect to the seed bed (22). The seedling raising material (23) has a hollow portion (23h) formed therein through which the seedling (19) from the seedbed (22) passes, and supports the growing seedling (19).

Description

Seedling raising material, seedling raising tool, seedling raising unit and seedling production method

Technical Field

The invention relates to a seedling raising material, a seedling raising tool, a seedling raising unit and a seedling production method.

Background

Vegetables and fruits such as tomatoes are cultivated in a greenhouse in what is called four seasons regardless of seasons throughout the year. Greenhouse cultivation is usually carried out by planting seedlings. As for the seedling, a seed of a bed sowed in a pot is germinated, a plug seedling (also referred to as a honeycomb formed seedling) obtained by raising the seedling 1 time, a so-called big seedling which can be planted by raising the plug seedling 2 times, and the like are grown. Although plug seedlings can also be planted, in the case of greenhouse cultivation, the plug seedlings become excessively lush after planting, and the excessive lush is particularly remarkable when a culture solution (nutrient cultivation) is used. Therefore, in greenhouse cultivation, large seedlings obtained by raising seedlings 2 times are preferable.

As a method for growing seedlings, for example, patent document 1 proposes a fully closed plant cultivation system (hereinafter, simply referred to as a cultivation system) isolated from an external space by a non-porous hydrophilic membrane and a cultivation method using the cultivation system. In this cultivation system, an inner space for accommodating a plant body such as a seedling is formed by a non-porous hydrophilic film (hereinafter, simply referred to as a hydrophilic film). Then, a part of the hydrophilic membrane on the external space side is brought into contact with water or a solution disposed in the external space. The hydrophilic membrane is supported by a support frame.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2009-072075

Disclosure of Invention

Technical problem to be solved by the invention

The production method of the large seedlings through the two seedling raising steps of 1 seedling raising and 2 seedling raising as described above lengthens the production period. The long term during production directly leads to a limitation of the annual production turnover and also to an increased risk of disease during growth. Therefore, it is required to improve the efficiency of growing large seedlings.

In addition, in the cultivation system of patent document 1, the hydrophilic membrane is softened by water during the seedling raising process for raising the seedlings, and thus the support frame for supporting the hydrophilic membrane becomes indispensable. Therefore, a step of providing a support frame and a step of providing a non-porous hydrophilic film on the provided support frame are required. Further, it takes time to set the support member itself such as the support frame, and it takes time to assume that the larger the seedling is, the more time. Further, the cultivation system of patent document 1 may be as follows: in the process of growing large seedlings, the hydrophilic membrane is gradually deteriorated by water, and as a result, the hydrophilic membrane is broken by contact with leaves and the like.

Accordingly, 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, which can be easily installed and improve the efficiency of raising seedlings for growing large seedlings.

Means for solving the technical problem

In order to solve the above problems, the seedling raising material of the present invention comprises a cellulose acylate, is cylindrical, is provided in a posture of standing up with respect to a bed, and has a hollow portion formed therein through which a seedling from the bed penetrates.

When the circle-equivalent diameter in the horizontal cross section of the hollow portion is Dcm and the height from the seedbed is H1cm, H1/D is preferably in the range of 0.5 to 10.0 inclusive.

The height is preferably in the range of 10cm to 50 cm. The circle-equivalent diameter is preferably in the range of 5cm to 40 cm.

The cellulose acylate preferably has a degree of substitution with acyl in the range of 2.00 or more and 2.97 or less, and has an acetyl group.

The seedling raising material preferably has a density of 200g/m ² D is not less than 1500g/m ² Moisture permeability in the range of d or less.

Preferably, the side surface of the seedbed is covered.

The seedling raising tool of the present invention comprises a seedling bed and the seedling raising material.

The seedling raising unit of the invention is provided with a seedling and the seedling raising tool.

The method for producing a seedling of the present invention includes an installation step of installing a tubular seedling raising material, in which a hollow portion through which a seedling from a bed is formed, in a standing posture with respect to the bed, and a seedling raising step, wherein the seedling raising material contains cellulose acylate.

In the seedling raising step, the seedlings are preferably grown to a height of 50% or more and 150% or less with respect to the height of the seedling raising material from the seedbed.

Effects of the invention

According to the invention, the device can be simply arranged, and the seedling raising efficiency of the grown seedlings can be improved.

Drawings

Fig. 1 is a partially cutaway schematic view of a seedling production apparatus.

Fig. 2 is an explanatory view of the seedling raising tool, in which fig. 2(a) is a side view of the seedling raising tool, and fig. 2(B) is a top view of the seedling raising tool.

Fig. 3 is an explanatory diagram of the circle-equivalent diameter.

Fig. 4 is a schematic view of a solution film forming apparatus.

Detailed Description

A seedling production apparatus 10 shown in fig. 1 is used for producing so-called big seedlings which can be planted by hydroponic cultivation, and includes a plurality of seedling raising units 12, a chamber (seedling raising room) 13, a light source unit 16, and a container 17. The seedling raising unit 12 has a seedling raising tool 18 and seedlings 19. The seedling 19 to be grown is a seedling smaller than the plug seedling, and more specifically, has a height of 1cm or more and 8cm or less and/or a leaf number of 2 or more and 5 or less. The seedling 19 is an example of a seedling, and therefore, the seedling 19 may be replaced with a seed (not shown), and in the case of the seed, the seedling production apparatus 10 performs germination and seedling growth (seedling raising). The seedlings 19 in this example are seedlings of tomatoes, but the seedlings are not limited to tomatoes, and may be seedlings of fruits and vegetables other than tomatoes or seedlings of leaf vegetables. Other examples of fruits and vegetables include eggplant, sweet pepper, colored pepper, cucumber, green soybean, corn, strawberry, and the like. Examples of the seedlings of leafy vegetables include seedlings of komatsuna, cabbage, lettuce, broccoli, celery, spinach, perilla, and the like.

The number of the seedling raising units 12 in the seedling production apparatus 10 is not limited to a plurality, and may be 1. The plurality of seedling raising units 12 are arranged in a square in the horizontal direction. The number of rows of the seedling raising units 12 (the number in the left-right direction in fig. 1) is 6 in this example, but the number is not limited to this example, and may be in the range of 1 row or more and 5 rows or less, or may be 7 rows or more. In the figure, an arrow X is given to the column direction, an arrow Y is given to the row direction orthogonal to the column direction X in the horizontal direction, and an arrow Z is given to the vertical upward direction. The number of rows (the number in the row direction Y) of the seedling raising units 12 is 3 in the present embodiment. The number of rows of the seedling raising units 12 is not limited to this example, and may be in 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 units 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 units 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 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 other than the square arrangement, or may be an irregular (random) arrangement. In this example, the plurality of seedling raising units 12 are arranged with a minute gap kept therebetween, and the distance D1 between the seedling raising units 12 is approximately 5 mm. Wherein the seedling raising units 12 may be in a state of being in contact with each other.

The upper portion of the container 17 is opened and receives water 21. The seedling raising tool 18 includes a bed 22 and a seedling raising material 23, and by placing the bed 22 in the container 17, at least a lower portion of the bed 22 is immersed in the water 21. The water 21 is supplied to the seedling 19 by this impregnation. The bed 22 may be any known material that can be used as a bed for hydroponic cultivation, and examples thereof include soil, sponge, and fibrous materials. In the present embodiment, Rockwool is used as the seedbed 22, specifically, a gridan (registered trademark) Rockwool cube manufactured by Rockwool b.v. netherlands. The seedling production device 10 is a device for cultivating the seedlings 19 by hydroponics, but the cultivation method by the seedling production device is not limited to hydroponics. Other cultivation methods include, for example, soil cultivation, nutrient cultivation, and high-level cultivation, and the bed 22 may be changed according to the cultivation method.

The seedling raising material 23 is formed in a cylindrical shape from a sheet body and is set in a posture of standing with respect to the bed 22 (setting step). The seedling raising material 23 is formed in a cylindrical shape, and a hollow portion 23h through which the seedling 19 from the bed 22 passes is formed inside. Thus, since the seedling 19 is supported from the periphery by the seedling material 23 during the seedling raising process, the seedling can be raised so as to extend upward without using, for example, a support column or the like other than the seedling material 23. Therefore, the seedlings were grown to be large seedlings in 1 seedling growing step. Thus, the seedlings do not need to be transplanted after primary seedling raising and are used for secondary seedling raising, and therefore, the large seedlings can be produced efficiently. Even when seeds are used instead of the seedling 19, the seedling is cultivated from germination to a large seedling, and thus the same effect is obtained. Of course, when the plug seedlings obtained in the first seedling raising are grown as the seedlings 19 of the present example, the seedlings are grown so as to extend upward without using a support or the like. Also, the seedling raising material 23 is provided in each of the plurality of beds 22, so that when the seedlings 19 grow into large seedlings, entanglement of stems and leaves of the seedlings 19 with each other can be prevented. As a result, it is easy to individually manage the growth of the plurality of seedlings 19, and therefore, there are advantages in that the efficiency of growing seedlings is improved, and it is easy to individually handle the grown seedlings when they are moved to another place.

The seedling raising material 23 is set in an upright posture in a state of covering the side surface of the bed 22. Thereby, the roots are prevented from tangling during the growth of the seedling 19. As a result, for example, when the produced seedlings are moved to another place, the seedlings can be easily handled individually. In addition, in the process of raising seedlings, when a disease or the like is confirmed in a specific part of seedlings 19, the seedlings can be easily taken out. The seedling raising material 23 of this example is in an upright posture in a state of covering the side surface of the bed 22, but is not limited to a mode of covering the side surface of the bed 22 as long as it is in an upright posture with respect to the bed 22. For example, it may be disposed on the bed 22. When disposed on the bed 22, the seedling raising material 23 may be placed on the bed 22, or the lower portion of the seedling raising material 23 may be inserted from above the bed 22 and fixed to the bed 22.

The seedling raising material 23 is in the form of a cylinder having 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 irregular shape. However, for example, when a plurality of cylindrical seedling raising materials 23 having the same size are arranged, the cross-sectional shape in the horizontal direction is made square, whereby the seedling producing apparatus 10 can be arranged in the most dense state, that is, flat packing can be performed. This is more preferable because more seedlings 19 can be produced in a limited installation area. Furthermore, the produced seedlings can be stored or distributed in a state of the seedling raising unit 12 or placed in a store front or the like, and can be arranged in a flat-packed manner in a limited installation place. For example, from the viewpoint of planar filling arrangement of a plurality of seedling raising materials having the same size and shape with each other, the shape in the horizontal direction is not limited to a square, and may be a regular triangle or a regular hexagon.

The seedling raising material 23 is an object formed by forming a cellulose acylate film into a cylindrical 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 cylindrical shape having a square cross section and fixing one end and the other end of the folded cellulose acylate film with an adhesive tape, but the forming method is not limited thereto. For example, one end and the other end of the folded cellulose acylate film may be fixed by heat-sealing. Further, it is also possible to prepare 4 rectangular cellulose acylate films and fix the cellulose acylate films to each other in the longitudinal direction to form the seedling raising material 23.

The seedling raising material 23 is formed of cellulose acylate, and therefore has high transparency and light from a light source 26 described later is efficiently irradiated to the seedling 12 and/or the bed 22. Further, since the cellulose acylate film has an appropriate hardness, it can be easily made to stand by itself by forming it into a cylindrical shape without using a support member such as a support frame, and thus the setting of the seedling raising material 23 is simple. Further, since the seedling raising material 23 contains cellulose acylate, the humidity in the hollow portion 23h rises due to the moisture in the seedling raising, and the equilibrium moisture content rises. The raising of the equilibrium moisture content allows the seedling raising material 23 to absorb moisture. The moisture in the hollow portion 23h is reduced by the absorption of the moisture of the seedling raising material, and the equilibrium moisture content of the seedling raising material 23 is reduced to release the moisture. In this way, the humidity change in the hollow portion 23h can be suppressed. As a result, effects such as (1) suppression of condensation on the inner wall 23i (see fig. 2) of the seedling raising material 23, (2) suppression of generation and proliferation of mold and pathogenic bacteria on the seedling 19 and/or the bed 22, (3) suppression of excessive overgrowth and/or excessive blooming of the seedling 19, (4) suppression of discoloration of the leaf of the seedling 19, and (5) reliable maintenance of the mechanism for opening and closing the stomata of the leaf of the seedling 19 can be obtained. Further, since the humidity rise in 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 time when the seedling 19 grows into a large seedling. Therefore, even a young seedling 19 immediately after germination can be continuously used during the period of growing into a large seedling by 1-time seedling raising. Alternatively, the plant can be continuously used even when grown into a large seedling from germination of seeds. Of course, it can be used for 2 seedlings in the case of performing two seedlings of 1 seedling and 2 seedlings.

The equilibrium moisture content is at 25 ℃ and 80% relative humidity. The temperature and the relative humidity correspond to those set as the environment for raising seedlings.

With respect to cellulose acylate, a hydroxyl group of cellulose is esterified by a carboxylic acid and thus has an acyl group. The degree of acyl 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. Thereby, the humidity change of the hollow portion 23h is suppressed to be small. The smaller the degree of acyl substitution, the more the amount of moisture absorbed by the seedling raising material 23, and therefore deformation due to water absorption is likely to occur, but it is preferable to set the degree of acyl substitution of the cellulose acylate constituting the seedling raising material 23 to 2.00 or more, because deformation can be more reliably suppressed. In addition, theoretically, the upper limit of the degree of substitution with acyl groups is 3.00, but it is difficult to synthesize cellulose acylate having a degree of substitution with acyl groups exceeding 2.97. Therefore, the degree of substitution with acyl groups of the cellulose acylate constituting the seedling raising material 23 is set to 2.97 or less.

The degree of acyl substitution of the cellulose acylate contained in the seedling raising material 23 is more preferably in the range of 2.40 to 2.95, and still more preferably in the range of 2.70 to 2.95. It is also known that the degree of substitution with acyl groups is the ratio of esterification of the hydroxyl groups of cellulose with carboxylic acid, i.e., the degree of substitution with acyl groups.

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 acetyl 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, alkenylcarbonyl ester, aromatic carbonyl ester, and aromatic alkylcarbonyl ester of cellulose, each of which may have a further substituted group. Examples thereof include propionyl group, butyryl group, pentanoyl group, hexanoyl group, octanoyl group, decanoyl group, dodecanoyl group, tridecanoyl group, tetradecanoyl group, hexadecanoyl group, octadecanoyl group, isobutyryl group, tert-butyryl group, cyclohexylcarbonyl group, oleoyl group, benzoyl group, naphthylcarbonyl group, cinnamoyl group and the like.

The acyl group of the cellulose acylate constituting the seedling raising material 23 may be only 1 kind, or may be 2 or more kinds, but preferably at least 1 kind is an acetyl group. Since the seedling raising material 23 easily absorbs moisture by the cellulose acylate having an acetyl group, the effect of suppressing the humidity change in the hollow portion 23h can be further improved. Most preferred is cellulose acylate in which all of the acyl groups are acetyl groups, that is, cellulose acylate is more preferably cellulose acetate.

The degree of acyl substitution can be determined by a conventional method. For example, the degree of acetylation (degree of acetyl substitution) may be according to ASTM: the degree of acetylation in D-817-91 (test method for cellulose acetate, etc.) is determined by measurement and calculation. Further, the degree of acylation (degree of substitution with acyl) can also be measured by measuring the distribution thereof by high performance liquid chromatography. As an example of this method, the degree of acetylation of cellulose acetate is measured as follows: the sample was dissolved in methylene chloride, and the degree of acetic acid formation was measured by linear gradient (linear-gradient) from a mixture of methanol and water (methanol: water mass ratio: 8:1) to a mixture of methylene chloride and methanol (methylene chloride: methanol mass ratio: 9:1) as an eluent by means of a column Novapak phenyl (Waters), and was determined by comparing the degree of acetic acid formation with a standard curve based on a standard sample having a different degree of acetic acid formation. These measurement methods can be obtained by referring to the methods described in japanese patent application laid-open No. 2003-201301. When the seedling raising material 23 contains an additive, the measurement of the degree of acetylation of the cellulose acylate is preferably a measurement based on high performance liquid chromatography.

The seedling raising material 23 may contain an additive. The additive is a plasticizer, and in this example, the plasticizer is also included. As the plasticizer, various known plasticizers can be used. Examples thereof include triphenyl acetate (TPP), diphenyl diphenylphosphate (BDP), ester derivatives of sugar, and ester oligomers, and the seedling raising material 23 of the present embodiment contains (contains) an ester derivative or ester oligomer of sugar. As the additive, the seedling raising materials 23 may contain, in addition to the plasticizer, an ultraviolet absorber, fine particles as a so-called matting agent that prevents the seedling raising materials 23 from adhering to each other, and the like.

The seedling raising material 23 preferably has a thickness of 200g/m ² D is not less than 1500g/m ² Moisture permeability in the range of d or less. Has a moisture permeability of 200g/m ² D is higher than, compared to less than 200g/m ² In the case of d, a large increase in the humidity of the hollow portion 23h during seedling raising can be more reliably suppressed. The water vapor permeability is 1500g/m ² D or less, compared with more than 1500g/m ² In the case of d, the standing posture can be maintained for a longer time. The moisture permeability is preferably 300m ² D is not less than 1300g/m ² D is not more than 400m, more preferably ² D is not less than 1200g/m ² D or less.

As a means for increasing the moisture permeability to 200g/m ² The method of d or more includes using an ester derivative and/or an ester oligomer of a sugar as a plasticizer, and reducing the amount of the plasticizer to a thickness of 200 μm or less. And, as a means for reducing the moisture permeability to 1500g/m ² D or less, the amount of the plasticizer is increased to make the thickness 40 μm or more.

The light source unit 16 is used to irradiate light to the bed 22 and/or the seedling 19. The light source unit 16 is used to irradiate light to the bed 22 before germination in the case of germination from seeds. 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 the plurality of light sources 26, and in this example, each light source 26 is provided on a lower surface that is an opposing surface opposing the plurality of seedling raising units 12. The controller 28 has a 1 st function of adjusting the amount of light emitted from each of the plurality of light sources 26 and a 2 nd function of controlling on/off of each of the plurality of light sources 26. The irradiation amount of light to the seedling 19 or the bed 22 can be adjusted by the function 1. The function 2 allows the timing and time of light irradiation to be adjusted according to the type and/or growth degree of the seedling 19. Thus, the light source 26 irradiates the seedling 19 or the bed 22 with light controlled by the controller 28. From this seedling 19 grows, in the case of seeds, germinates. The distance from the light source 26 to the seedling raising unit 12 is set to about 100mm in this example, but is not limited to this example.

The chamber 13 houses the seedling raising unit 12, the light source 26 and the support plate 27 of the light source unit 16, and the container 17, and has a temperature and humidity controller 31. The temperature and humidity regulator 31 regulates the growth environment of the seedling 19 by regulating the temperature and humidity inside the chamber 13. The temperature inside the chamber 13 is not particularly limited, but is preferably within a range of 10 ℃ to 40 ℃. In this example, the temperature was set to 20 ℃ to confirm that the temperature varied within a range of 17.5 ℃ to 22.5 ℃. The humidity inside the chamber 13 is not particularly limited, and is preferably a relative humidity within a range of 50% to 80%. In this example, the control is in the range of 40.5% to 91%. In addition, when the seedling raising unit 12 is installed outdoors or the like without a roof and the chamber 13 is not used, an upper member 23t (refer to fig. 2) made of the same material as or a different material from the seedling raising material 23 may be provided on the seedling raising material 23.

The seedlings 19 are cultured by supplying water 21 to the seedlings 19, irradiating light, and controlling temperature and humidity (a seedling culture step). In the seedling raising method of this example, since the seedling raising material 23 is used, the seedling 19 grows into a large seedling in 1 seedling raising step.

The seedling raising means 18 will be described in further detail with reference to fig. 2. The circle-equivalent diameter in the horizontal cross section of the hollow portion 23H is designated as Dcm, and the height from the bed 22 is designated as H1 cm. H1/D, which is the division of the height H1cm of the material 23 by the circle-equivalent diameter Dcm, is preferably in the range of 0.5 to 10.0, and is set to, for example, 3.5 in this example. When H1/D is 0.5 or more, the seedling 19 is reliably lengthened in the standing posture as compared with the case where H1/D is less than 0.5. Further, the raising posture of the seedling raising material 23 during the seedling raising can be maintained more reliably by setting the H1/D to 10.0 or less. H1/D is more preferably in the range of 1.0 to 8.0 inclusive, and still more preferably in the range of 1.5 to 6.0 inclusive. The circle-equivalent diameter D (unit: cm) is the diameter of a circle C drawn to have the same area as the hollow 23h surrounded by the seedling raising material 23 shown in FIG. 2B (see FIG. 3).

When H1/D is in the range of 0.5 to 10.0, the height H1 (unit; cm) is preferably in the range of 10 to 70cm, for example, 30cm in the present example. By setting the height H1 to 10cm or more, the seedling 19 can be more reliably lengthened in the standing posture. By setting the height H1 to 70cm or less, the standing posture of the seedling raising material 23 during the raising of seedlings can be maintained more reliably. The height H1 is more preferably in the range of 15cm to 50cm, and still more preferably in the range of 20cm to 40 cm.

When H1/D is in the range of 0.5 to 10.0, the circle-equivalent diameter D is preferably in the range of 5 to 40cm, for example, 8.5cm in the present example. By setting the equivalent circle diameter D to 5cm or more, the standing posture of the seedling material 23 during seedling can be maintained more reliably than in the case of less than 5 cm. When the equivalent circle diameter D is 40cm or less, the area occupied by the seedling material 23 and thus the area occupied by the seedling raising unit 12 can be reduced, and therefore a target planting number of large seedlings can be reliably secured. The circle-equivalent diameter D is more preferably in the range of 7cm to 30cm, and still more preferably in the range of 8cm to 20 cm.

The thickness T of the seedling raising material 23 is preferably in the range of 20 μm to 200 μm, and is 100 μm in this example. By having a thickness of 20 μm or more, the setting is simpler than in the case of less than 20 μm, and the standing posture can be maintained more reliably during the growth period of the grown-up seedling. When the thickness T is 200 μm or less, the seedling raising material 23 is easily bent when it is formed into a cylindrical shape and is less likely to be broken when it is bent, as compared with the case where it is larger than 200 μm. The thickness T is preferably 30 μm to 150 μm, and particularly preferably 40 μm to 130 μm.

T/H1, which divides the thickness T (unit; μm) by the height H1, is preferably 5.0X 10 ^-5 Above and 2.0X 10 ^-3 Within the following ranges. The passing T/H1 is 5.0 multiplied by 10 ^-5 Above, as compared to less than 5.0X 10 ^-5 In the case of (2), it is easy to set in the standing posture, and the seedling raising material 23 is moderately widened in accordance with the widening of the upper leaves in the course of growing into a large seedling, and the standing posture can be maintained more reliably during growth. The passing ratio of T/H1 is 2.0 multiplied by 10 ^-3 In comparison with a ratio of 2.0X 10 ^-3 In the larger case, the seedling raising material 23 does not excessively inhibit the widening of the upper leaves during the course of raising into large seedlings, and therefore, larger seedlings of higher quality with moderately widened upper leaves can be obtained.

In the seedling raising step, the seedling 19 is preferably grown to a height of 50% to 150% with respect to the height H1, in this example, to a height of 130%. In addition, the height of the seedling is the height from the bed 22, and is denoted by a symbol H2 in FIG. 2. By growing the seedling 19 to a height of 50% or more with respect to the height H1, a large seedling suitable for planting can be grown more reliably. By growing the seedlings 19 to a height of 150% or less with respect to the height H, leaf entanglement between the seedlings 19 and leaf sagging and/or lodging above the seedlings 19 can be suppressed as compared with the case where the height H exceeds 150%, and as a result, transplanting can be facilitated and a large seedling of good quality can be obtained.

When the seedlings 19 were grown using the seedling raising material 23 having the above-described structure, the following results were obtained as compared with the case where the seedlings 19 were grown using a seedling raising material formed of a polyethylene terephthalate (hereinafter, referred to as PET) film. The shape and size of the seedling raising material formed of a PET film are the same as those of the seedling raising material 23. The following SPAD value "SPAD" is an abbreviation for the practical utility of the large-scale operation soil/crop analysis system in the agricultural and forestry, aquatic product, agricultural and silkworm horticulture bureau, and the SPAD value is an index of the chlorophyll amount developed by SPAD. The SPAD value was measured at the front end portion of the largest leaf (largest leaf) among the obtained plural leaves of the seedling 19. The number of roots described below counts the number of adventitious roots occurring on the surface of rockwool as the seedbed 22. The adventitious root is a spindly root growth that occurs when the main root is not developed, and occurs when the surface is excessively wet.

(1) The maximum leaf length (length of the longest leaf among a plurality of leaves) in the obtained seedling was 32.3cm, which is longer than 29.3cm in the case of the seedling raising material formed of a PET film, with a significant difference. Namely, the growth of each leaf was excellent and better.

(2) The SPAD value measured by the chlorophyll meter SPAD-502Plus manufactured by KONICA MINOLTA, INC. was 47.6, which is a significant difference, compared with 37.5 in the case of the seedling raising material formed of a PET film. Namely, chlorophyll was more abundant, and was better.

(3) The number of roots was 8.0, which was a significant difference from 28.2 plants when the seedling raising material formed of a PET film was used. That is, it is preferable that the adventitious roots are not excessively numerous and the surface of the medium is maintained at a level not excessively wet.

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

The solution film-forming apparatus 50 includes a casting unit 55, a roll dryer 56, and a winder 57 in this order from the upstream side. The casting unit 55 includes a belt 61 formed in an endless shape, a pair of rollers 62 which travel in the longitudinal direction while supporting the belt 61 on the circumferential surface, a blower 63, a casting die 64, and a peeling roller 65. At least one of the pair of rollers 62 rotates in the circumferential direction, and the wound conveyor belt 61 continuously travels in the longitudinal direction by the rotation. The casting die 64 is disposed above one of the pair of rollers 62 in this example, but may be disposed above the belt 61 between one and the other of the pair of rollers 62.

The belt 61 is a support for the casting film 66 described later, and has a length of 55m to 200m, a width of 150cm to 500cm, and a thickness of 1.0mm to 2.0mm, for example.

The casting die 64 causes the supplied dope 52 to continuously flow out from the outflow port 64a opposed to the belt 61. By continuously flowing out the dope 52 to the running belt 61, the dope 52 is extended upstream of the belt 61, forming a casting film 66 on the belt 61.

The pair of rollers 62 includes a temperature controller (not shown) for adjusting the temperature of the peripheral surface. The temperature of the casting film 66 is adjusted via the belt 61 by the roller 62 whose circumferential surface temperature is adjusted. In the case of a so-called dry gelation method in which drying is accelerated to cure (gel) by heating the casting film 66, the temperature of the peripheral surface of the roll 62 may be set in a range of, for example, 15 ℃ to 35 ℃. In the case of the so-called cooling gelation method in which the casting film 66 is cooled and solidified, the temperature of the peripheral surface of the roll 62 may be set in a range of-15 ℃ to 5 ℃. In this embodiment, a dry gelation method is adopted.

The air blower 63 is used to dry the formed casting film 66. The blower 63 is disposed opposite to the conveyor 61. The air blower 63 promotes drying of the casting film 66 by sending gas to the casting film 66. The gas to be sent is air heated to 100 ℃ in the present embodiment, but the temperature is not limited to 100 ℃ and the gas is not limited to air. By the drying by the air blower 63, the casting film 66 is gelled more rapidly. Further, by the gelation, the casting film 66 becomes conveyable hardness.

The puddle 52 reaching the belt 61 from the casting die 64 may be provided with a decompression chamber (not shown) upstream in the traveling direction of the belt 61, so-called build-up (bead). The decompression chamber sucks the ambient gas in the upstream side region of the discharged paste 52 to decompress the region.

After the casting film 66 is solidified on the belt 61 to an extent capable of being conveyed in the roller dryer 56, it is peeled from the belt 61 in a state of containing a solvent. The peeling roller 65 is used to continuously peel the casting film 66 from the belt 61. The peeling roller 65 supports, for example, the cellulose acylate film 51 formed by peeling from the belt 61 from below, and holds the peeling position PP at which the casting film 66 is peeled from the belt 61 fixed. The peeling method may be any of a method of pulling up the cellulose acylate film 51 from the downstream side, a method of rotating the peeling roller 65 in the circumferential direction, and the like.

In the case of the dry gelation method, the stripping from the belt 61 is performed, for example, in a range where the solvent content of the casting film 66 is 3 mass% or more and 100 mass% or less, and is performed at 100 mass% in the present embodiment. In the case of the cooling gelation method, for example, the solvent content of the casting film 66 is preferably in a range of 100 mass% or more and 300 mass% or less. In the present specification, the solvent content (unit;%) is a value based on a dry weight, and specifically, a percentage obtained by { x/(y-x) } × 100 is given when x represents the mass of the solvent and y represents the mass of the cellulose acylate film 51 for which the solvent content is obtained.

As above, the casting unit 55 forms the cellulose acylate film 51 from the dope 52. The casting of the dope 52 and the peeling of the casting film 66 are repeated by the circulating travel of the belt 61.

The roll dryer 56 is used for drying the formed cellulose acylate film 51, and includes a plurality of rolls 73 and an air conditioner (not shown). Each roller 73 supports the cellulose acylate film 51 on the circumferential 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 dried while being supported and conveyed by the rollers 73. The winder 57 is used to wind the long cellulose acylate film 51, and the cellulose acylate film 51 is wound in a roll shape by this winder 57. Further, between the casting unit 55 and the roll dryer 56, a tenter (not shown) may be provided which extends the cellulose acylate film 51 in the width direction. A cutter (not shown) may be provided between the roll dryer 56 and the winder 57, for example, and the side portions of the cellulose acylate film 51 may be continuously cut off by the cutter. The cellulose acylate film 51 is cut into a rectangular shape and then formed into a cylindrical shape as described above, thereby producing the seedling raising material 23.

Examples of the present invention and comparative examples thereof are shown below.

Examples

[ example 1] to [ example 22]

A cellulose acylate film 51 having a width of 1340cm was produced by a solution film-forming apparatus 50, and was wound up by a length of 2000m by a winder 57. Seedling raising materials 23 were produced from the respective cellulose acylate films 51 by the foregoing method, and 18 seedling raising units 12 each using the respective seedling raising materials 23 were prepared. Tomato seedlings 19 were grown in each seedling raising means 12, and examples 1 to 11 were provided.

The formulation of cement 52 is as follows. The solid component described below is a solid component constituting the cellulose acylate film 51.

The 1 st component of the solid component is cellulose acylate, and in table 1, the column of "substance" of the "1 st component" is described as "cellulose acylate". All the acyl groups in the cellulose acylate are acetyl groups, and the viscosity average degree of polymerization is 320.

The 2 nd component of the solid content is a or B shown in the column "2 nd component" in table 1. A is an ester derivative of sugar, specifically, a benzoate ester of sucrose (manufactured by DKS co.ltd. B is an ester oligomer, specifically an oligomer having an ester of adipic acid and ethylene glycol as a repeating unit (number average molecular weight of 1000 by a terminal functional group quantitative method). The "amount of the 2 nd component" in table 1 is the mass of the 2 nd component assuming that the mass of the cellulose acylate is 100, and the "PHR" in table 1 is an abbreviation indicating parts by mass per 100 parts of the resin (per rounded resin). The 3 rd component of the solid component is fine particles of silica, which is R972 manufactured by NIPPON AEROSIL co.

The cement 52 was produced by the following method. First, the solid components, component 1 and component 2, and the solvent, which is a mixture of methylene chloride and methanol, were charged into a closed vessel, and the solvent was dissolved in component 1 and component 2 by stirring in the closed vessel while keeping the temperature at 40 ℃. The solid component 3 was dispersed in a mixture of methylene chloride and methanol, and the obtained dispersion was added to the above-mentioned closed vessel containing the solution in which the solid components 1 and 2 were dissolved, to thereby disperse the solid components. The dope 52 thus obtained was left to stand, filtered through filter paper while maintaining the temperature at 30 ℃, and then subjected to defoaming treatment to be used for casting in the solution film-forming apparatus 50.

The dope 52 of 30 ℃ is cast from the casting die 64 to form a casting film 66. Air of 100 ℃ was blown by an air blower 63 to the casting film 66 immediately after the formation, and the dried casting film 66 was peeled from the belt 61 by a peeling roller 65. The temperature of the conveyor belt 61 at the peeling position PP was 10 ℃. The casting film 66 is peeled after 120 seconds has elapsed after the formation. The solvent content of the casting film 66 at the peeling position PP is 100 mass%. The stripping was carried out with a tension of 150N/m. The tension is a force per 1m width of the casting film 66. The formed cellulose acylate film 51 is taken into a roll dryer 56 and dried while being conveyed in a state of being given a tension in the longitudinal direction by a plurality of rolls 73. The tensile force applied in the longitudinal direction was 100N/m. This tension is a force per 1m width of the cellulose acylate film 51. The roll dryer 56 has a 1 st zone on the upstream side and a 2 nd zone on the downstream side, the 1 st zone being set to 80 ℃ and the 2 nd zone being set to 120 ℃. The cellulose acylate film 51 was conveyed for 5 minutes in zone 1 and 10 minutes in zone 2. The solvent content of the cellulose acylate film 51 wound up by the winder 57 was 0.3% by mass.

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

In examples 1 to 21, seed culture soil was filled in a plug for seeding, peach tree YOKE (TAKI & co., LTD) was seeded, the seed was cultivated for 16 days to germinate, and the seed was transplanted as a seedling 19 into a seedbed 22 of a seedling-raising tool 18. The 18 seedling raising units 12 using the seedling raising material 23 were arranged side by side in one chamber 13, and each seedling 19 was grown for 14 days in this state.

In example 22, the foregoing peach tree YOKE is sown in the seedbed 22 of each of the 18

seedling raising tools

18, and 18 seedling raising units 12 are arranged side by side in one chamber 13. In this state, germination and seedling were carried out. The growth period was 30 days. Other conditions of example 22 were the same as in 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. Maintenance of upright posture

When the standing posture of the seedling raising material 23 is maintained during the growth of the seedling 19, the seedling 19 can be grown upward and grown to a large size. 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 seedlings which have maintained the standing posture during the above-mentioned seedling raising period, and are qualified. D is unqualified.

A; when the seedling is finished, the change of the seedling in the setting can not be confirmed

B; at the end of the nursery, wrinkling and/or deformation was observed very slightly, but the erect posture was maintained and was able to be reused.

C; at the end of the seedling raising, wrinkling and/or deformation were observed, and the standing posture was maintained although the reuse was impossible.

D; in the course of seedling raising, wrinkling and deformation were observed, and self-standing was not observed in the course of seedling raising.

2. Height of the produced seedlings

At the end of the nursery, the height of the seedlings 19 was measured. The results are shown in the column "height of seedling" in Table 1 and are reported in cm. In addition, the heights of the 18 seedlings 19 grown were measured in each example, and the average value of these heights was defined as the height of the seedling shown in Table 1. When the height is more than 15cm, the seedlings grow into big seedlings capable of being planted, and the seedlings are judged to be qualified. The height is more than 25cm, and the device is particularly suitable for field planting. If the height is less than 15cm, it is necessary to perform secondary seedling culture before field planting, and the seedling is determined to be unqualified due to low production efficiency.

3. Ease of transplanting seedlings

After completion of the seedling raising, the obtained seedlings 19 were used for the planting work and evaluated according to the following criteria. P is qualified, F is unqualified.

P; the adjacent seedlings 19 are not entangled with each other, and it is easy to individually handle a plurality of seedlings 19.

F; the adjacent seedlings 19 are entangled with each other, and it takes time to individually treat a plurality of seedlings 19.

4. Quality of the seedlings

When seedlings obtained by growth were planted in a field, the state after planting was visually observed, and evaluation according to the following criteria was performed as quality evaluation of the seedlings. In Table 1, A to C are passed, and D is failed. A; from the upper part of the seedling to the whole, the leaves are more and moderately wider, and the stem is solid and self-standing. B; several leaves depend downwardly from the upper part of the seedling, but are also substantially free-standing without support. C; the leaves of the seedling hang downward and the upper part bends downward from the middle part of the stem. D; the seedling is lodged or cannot stand up. The lower leaves were particularly found to be yellow.

Comparative examples 1 and 2

Seedling was carried out under the same conditions as in example 1 except that the seedling raising material 23 was not used as comparative example 1. In comparative example 1, since the seedling raising material 23 was not used, the column of "seedling raising material" in table 1 is indicated as "-" except for the column of "presence or absence". In comparative example 2, a polyethylene terephthalate (hereinafter, referred to as PET) film was formed into a cylindrical shape similar to the seedling raising material 23, and was used as the seedling raising material, and seedlings were raised under the same conditions as in example 1. The PET film used was a film obtained by TORAY INDUSTRIES, LUMIRROR (registered trademark) T60#100 (thickness: 100 μm) manufactured by INC.

The maintenance of the upright posture of the seedling raising material, the height of the seedling obtained by growth, the ease of transplanting the obtained seedling, and the post-planting quality of the obtained seedling were evaluated by the same methods and criteria as in the examples. In comparative example 1, no seedling raising material was used, and therefore, the maintenance of the standing posture of the seedling raising material was not evaluated. Therefore, in the column "maintenance of standing posture" in table 1, "-" indicating no evaluation is described. The evaluation results are shown in table 1.

Description of the symbols

10 seedling apparatus for producing

12 seedling raising unit

13 chamber

16 light source unit

17 Container

18 seedling raising tool

19 seedling (Miao)

21 water

22 seedbed

23 seedling raising material

Hollow part of 23h

23i inner wall

23t Upper part

26 light source

27 supporting plate

28 controller

31 temperature and humidity regulator

50 solution film making device

51-cellulose acylate film

52 mucilage

55 casting unit

56-roller dryer

57 coiling machine

61 conveyor belt

62 roller

63 blower

64 casting die

64a outflow opening

65 strip roller

66 cast film

73 roller

C circle

Equivalent diameter of D circle

Distance D1

H1 height of seedling raising material from seedbed

Height of H2 seedling

PP stripping position

Thickness of T

In the X row direction

Direction of Y line

Upward Z plumb

Claims

1. A seedling raising material comprising a cellulose acylate,

the seedling raising material is cylindrical, is arranged in a standing posture relative to the seedbed, is internally provided with a hollow part through which the seedlings from the seedbed penetrate, and supports the seedlings from the periphery by the seedling raising material during the seedling raising process,

h1 is in the range of 10cm to 50cm when the height from above the seedbed is H1cm,

the cellulose acylate has an acyl substitution degree in the range of 2.00 or more and 2.97 or less, and has an acetyl group,

the seedling raising material has a weight of 200g/m ² D is not less than 1500g/m ² Moisture permeability in the range of d or less.

2. A seedling raising material according to claim 1,

when the circle-equivalent diameter in the horizontal cross section of the hollow portion is Dcm, H1/D is in the range of 0.5 to 10.0.

3. A seedling raising material according to claim 2,

the circle-equivalent diameter is in the range of 5cm or more and 40cm or less.

4. A seedling raising material according to any one of claims 1 to 3, which is provided in a state of covering a side surface of the bed.

5. A seedling raising tool is provided with:

seedbed, and

a seedling raising material as set forth in any one of claims 1 to 4.

6. A seedling raising unit is provided with:

seedlings and seeds of

A seedling raising implement according to claim 5.

7. A method for producing a seedling, comprising:

an installation step of installing a cylindrical seedling raising material having a hollow portion through which a seedling from a bed is inserted, in a standing posture with respect to the bed, and supporting the seedling from the periphery by the seedling raising material during the seedling raising process, and

a seedling raising process step of carrying out seedling raising,

h1 is in the range of 10cm to 50cm when the height of the seedling raising material from above the bed is H1cm,

the seedling raising material contains cellulose acylate having an acyl substitution degree in a range of 2.00 or more and 2.97 or less and having an acetyl group,

8. The method for producing a seedling according to claim 7,

9. The method for producing a seedling according to claim 7 or 8, wherein,

the seedling raising step is configured to grow the seedling to a height of 50% or more and 150% or less with respect to the height of the seedling material from the seedbed.