JP3029352B2 - Biodegradable nursery pot - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a seedling pot for agricultural and horticultural use. More specifically, the present invention relates to a biodegradable seedling raising pot requiring degradability.

[0002]

2. Description of the Related Art In recent years, with the advancement of agricultural techniques, a method from seeding to raising seedlings is performed in a controlled facility such as a vinyl house, and after obtaining excellent seedlings, they are transplanted to an actual field. Is to be performed. Conventionally, most pots used for this purpose are made of a resin having no biodegradability, such as vinyl chloride or polyethylene. Since these are not biodegradable, the seedlings need to be pulled out from the pot and transplanted, which is not only complicated in operation but also has a problem of planting damage at the root part in particular, and improvement has been desired.

[0003] Attempts to apply biodegradable materials to the field of agriculture and horticulture are disclosed in JP-A-51-57533 and JP-A-54-123.
453, JP-A-2-6689, JP-A-2-28613
Are disclosed. JP-A-51-57533 discloses that
The present invention relates to an implantable flowerpot made of a material obtained by mixing cellulose such as sawdust with a non-biodegradable material such as polyethylene, nylon, and epoxy resin.
JP-A-54-123453 discloses a method of using a copolymer composed of an aliphatic polyester and an aliphatic polyamide as a material for a plant pot which decomposes and disappears. JP-A-2-6689 uses a composite of cellulose and chitosan. In this case, it is described that biodegradability can be controlled by the molecular weight and the amount of chitosan. JP-A-2-28613 discloses a method in which a film of a polyhydroxybutyric acid / polyhydroxyvaleric acid copolymer is formed on the surface to improve the water resistance and strength of a pot of plant fiber such as paper to form a composite. Have been.

[0004] Many reviews on biodegradable polymers suggest that aliphatic polyester compounds may be applied to pots for agricultural and horticultural use, but specific examples have been reported. Absent. Polym by Gillett
ers and Ecological Probe
ms (1973) (Plenum Press, Ne)
w York), page 74, reports the results of pot burying tests using polycaprolactone.
Destruction of the shape has been progressing since about six months.

[0005]

The pot for raising seedlings aimed at by the present invention is used for cultivation of tomato, cucumber, cabbage, Chinese cabbage, lettuce, eggplant, houseplants, trees and the like.
After obtaining seedlings grown under controlled conditions of about 20 ° C in a vinyl house for two weeks to one month, and transplanted to the actual field, the containers decompose in about one month, The condition must be met without adversely affecting the tension and not inducing unwanted illness. As described above, there has been a demand for a pot in which the biodegradability of the container is controlled. However, the conventional method has a problem that the biodegradability is slow (see the method of Gillet et al., JP-A-51-57533, JP-A-54-1979). 123453), it is difficult to control the thickness (JP-A-2-6689), or the strength is not sufficient (JP-A-2-28613).
Was not known.

[0006]

For this purpose, the present inventors have studied the use of an aliphatic polyester compound having the best biodegradability as the material of the pot or a modified product thereof. As a result, we know that mainly the pot volume and the pot thickness have a great effect on the growth of the seedlings and the crops after transplanting, and obtain a sophisticated seedling pot by limiting the thickness and shape to a certain range. The goal was achieved.

That is, the present invention provides: (1) a film thickness of 50 μm to 200 μm and a diameter of 3 to 10 c
A pot for raising seedling, which is a cylindrical or square container having a length of 3 to 10 cm and a length of 3 to 15 cm in a cylindrical or square shape, the material of which is a biodegradable aliphatic polyester compound or a modified product thereof. 2) The modified product is obtained by adding one aliphatic polyester compound.
Seedling pot characterized by being a polymer modified with 0% by weight or less of a diisocyanate compound (3) A fungicide is contained (1) (2)
(4) The seedling pot according to the above (1) to (3), wherein the material contains activated carbon and / or carbon black.

Hereinafter, the seedling raising pot of the present invention will be described in detail. As the material of the polymer used for the seedling raising pot of the present invention, a biodegradable aliphatic polyester compound or a modified product thereof is used. Specifically, poly-3-hydroxybutyric acid, 3-hydroxybutyric acid and 3-hydroxyvaleric acid are used. , Copolymers of 3-hydroxybutyric acid and 4-hydroxybutyric acid, or those produced by microorganisms such as polyesters, which are collectively referred to as poly-3-hydroxyalkanoic acids, polylactic acid, polyglycolic acid, and polypropylic acid. Polyhydroxycarboxylic acids produced by a synthetic method such as lactone, polybutyrolactone, polycaprolactone and the like can be mentioned.

Further, a polyester produced by condensation polymerization of an aliphatic dibasic acid and an aliphatic diol as described below can also be used. That is, aliphatic dibasic acids include succinic acid, adipic acid, sebacic acid, decanedicarboxylic acid, etc., and aliphatic diols include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, and the like. , 10-decandione and the like.

The above aliphatic polyester compound is preferably modified with 10% by weight or less of a diisocyanate compound to change biodegradability and mechanical strength. Examples of the diisocyanate compound used for this purpose include 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1,12-diisocyanatododecane,
Examples include isophorone diisocyanate and 4,4′-diisocyanatodiphenylmethane.

This reforming is carried out by using a solvent having no active hydrogen such as benzene, toluene, xylene, dichloromethane,
1,2-dichloroethane, chloroform, ethyl acetate,
The reaction can be carried out using ethyl lactate, ethyl lactate, dioxane, tetrahydrofuran, dimethylformamide, dimethylsulfoxide, or the like, but may be carried out with heating and melting without solvent. The reaction temperature is preferably from room temperature to about 200 ° C.

The method for producing the seedling raising pot of the present invention will be described. A film made of the above material is cut into a desired size, and a method of forming a target shape by using an adhesive or by means of heat melting, or by a method such as an injection molding method. There is no particular limitation.

Next, the dimensions and the shape will be described. The most important dimension is the thickness. As described above, between 2 weeks and 1 month is a period for raising seedlings. At this time, the shape is maintained firmly, and after transplanting to the actual field, it is decomposed in about 1 month and the shape is maintained. It is necessary that there is nothing. For this purpose, 200 μm or less, preferably 150 μm
The thickness must be from m to 20 μm, and when it exceeds 200 μm, it has been confirmed that a steady increase in root mass and leaf number after transplantation is prevented and growth inhibition occurs. If it is less than 20 μm, there is a problem in strength and handling. The height of the pot is preferably 3 to 12 cm. Also, the diameter or one side is 3-10c
m is preferably a cylindrical or square container of 3 to 7 cm. These are used to secure the amount of soil necessary for growth from germination to transplantation, and to grow seedlings before the pot is decomposed. It is the size that is adopted so as not to cause inhibition. A cylindrical shape is most preferable in terms of handling, disassembly, and manufacturing, but may be a square shape, and furthermore, they may be slightly deformed, in other words, may have a volume of the above-described dimensions. . It is better to make a drain hole on the bottom, but it is not necessary.

Polymer by James Gillett
s and EcologicalProblems
(1973) (Plenum Press), p. 73, reports the results of a soil embedding test of a container using polycaprolactone, but the shape has finally collapsed after 6 months, and this is used for a seedling pot. It is considered impossible to do so. However, the present inventors have found that polycaprolactone can be sufficiently used by limiting its thickness and size.

Plants that can use the seedling raising pot of the present invention include tomato, cucumber, eggplant, cabbage, Chinese cabbage,
Lettuce, long onion, broad beans, pak choi, parsley, etc.
Under controlled conditions of about 0 ° C. to 30 ° C., horticultural crops such as vegetables for which seedlings need to be obtained, and anemones, calendulas that require transplanting within one or two months after sowing, regardless of crops, Flowers such as Nemophila, Kikyo, Rhodanse, Calseolaria, Papaver rhododendron, Trichogneum japonicum, and Knapweed can be mentioned. .
By using the above crops and flowers, sufficient strength can be maintained until transplantation even in the markets of seedlings and flowers.

It is necessary that the seedlings growing in the seedling pots and after transplanting do not induce unwanted diseases. Normal,
It is necessary to spray a fungicide when a disease occurs, such as tomatoes, which tend to cause disease, which takes time and labor. By adding a fungicide to the seedling pot of the present invention, the fungicide is released little by little with the decomposition of the seedling pot, exhibits a sustained release bactericidal effect, prevents the occurrence of mold, and prevents the disease of seedlings. It can also save time and labor in work, and give good results in work hygiene.

The types of fungicides that can be contained in the seedling raising pot of the present invention include thiabendazole, daconil,
A mildewproofing agent such as lidomill or a copper compound is suitable, but a small-granular or powdery one is preferable because it must be added to the polymer. Also, even if it is something other than that,
If it is soluble in a polymer or a solvent, it can be added. The amount of fungicide to be added is 1% based on the polymer
It is about. It is necessary that the bactericide added to the polymer has a sufficient bactericidal effect and does not cause phytotoxicity. For this purpose, the germicide is added to the weight of the polymer at 1%.
% Or less, preferably 0.1% to 0.5%. Alternatively, an insecticide, a planting agent and the like can be added to the material for forming the pot of the present invention, in addition to the bactericide.

Activated carbon and / or carbon black can be added to the seedling raising pot of the present invention for the purpose of shading in order to protect the roots from light. In addition, a biodegradable coloring agent or the like can be added. As a coloring agent to be added, black is desirable in order to expect soiling of the seedling pot and a high light-shielding effect until transplantation, but if it is biodegradable,
There is no particular limitation. Activated carbon added to the polymer and / or
Alternatively, carbon black needs to exhibit a sufficient light-shielding effect within a range that does not reduce the strength of the added polymer. For this purpose, the total amount of activated carbon and / or carbon black is preferably 10% or less, preferably 0.5 to 8.0%, based on the weight of the polymer.

[0019]

EXAMPLES The present invention will be described more specifically with reference to examples.

Examples 1 to 10 Poly-3-hydroxybutyric acid / poly-3 derived from microbial fermentation synthesis
-Hydroxyvaleric acid copolymer (hereinafter referred to as Poly (3HB)
-3HV), a polycaprolactone by chemical synthesis, a modified product of polybutylene adipate / hexamethylene diisocyanate (hereinafter abbreviated as PBA (modified product)). Was processed into a seedling pot. The soil was preliminarily sterilized with chlorpicrin and mixed in the ratio of humus to soil: 3, and a fertilizer equivalent to 0.9% of the sterilized soil was added.
Fertilizer is Chissofosca (N: P: K = 13: 12: 1)
0) was used. The soil was packed in seedling pots, and three pots were sown for each pot. The result when tomato is selected as an example is shown. The cultivar used was Mizuhide tomato (production site: Gunma Prefecture), and the seeding depth was 1.5 cm. Two weeks after sowing, thinning was performed so that each pot had one seedling. The germination rate was 100%. Three weeks after sowing, the whole seedling pot was transplanted into the soil so that the pot was completely buried in the soil.

At this time, there was no large growth difference between the seedling pots of the examples. In addition, each seedling pot maintained sufficient strength and shape, and the working efficiency at the time of transplantation was very good. Normal seedlings may stop growing for 3 days to 1 week after transplanting due to planting damage, etc., but the seedlings transplanted together with the seedling pot also showed good growth after transplantation. Also, after transplantation,
The seedlings grew well, and no disease or phytotoxicity occurred during the experiment, but mold generation was observed in the pot without the fungicide.

Four weeks after transplantation, the decomposition state of each pot,
A final survey was conducted on the growth of the seedlings. All the tests were performed in a greenhouse. The results are shown on the next page. In addition,
Five test pots were used for each test plot of nursery pots, and the results were average values of each pot. Seedlings were grown in a normal polyvinyl chloride pot, removed at the time of transplantation and transplanted.

Example 1 Poly (3HB-3HV) 50 None 2 Poly (3HB-3HV) 50 Daconyl 0.23 Poly (3HB-3HV) Type of polymer Film thickness Type of disinfectant (μm) (%) 50 Thiabendazole 0.2 4 Poly (3HB-3HV) 100 None 5 Polycaprolactone 50 None 6 Polycaprolactone 50 Daconyl 0.27 Polycaprolactone 50 Thiabendazole 0.28 PBA (Modified) 50 None 9 PBA (Modified) 50 Daconyl 0.2 10 PBA (modified) 50 Thiabendazole 0.2 Comparative Example 1 Poly (3HB-3HV) 200 None

Growth condition (compared to "Control") ：: No adverse effect on growth. +: Slight adverse effects on growth are observed. ++: An adverse effect on growth is clearly observed. Root mass 3.0: Root mass is large. 2.0: Root mass is slightly small. 1.0: Very low root mass. Degradation index of polymer (after 4 months) 5.0: Completely degraded. 4.0: Almost disassembled and the outer shape is not stopped. 3.0: Decomposition has progressed well, but the outer shape is observed. 2.0: Decomposition is progressing, but the outer shape remains clearly. 1.0: Almost no decomposition or only the vicinity of the bottom is decomposed.

[0025]

[Table 1]

[0026]

[Table 2]

[0027]

[Table 3]

In the case of using a biodegradable pot without a fungicide, growth before transplantation is slightly inferior. This is considered to be due to the occurrence of mold only in the pots in this area, which adversely affected the growth of the seedlings. One week after transplanting, the seedlings in the pot without the fungicide almost caught up with the growth of the control seedlings. This indicates that the control at the time of transplanting had a slightly slower growth due to root planting damage, whereas the one using the biodegradable seedling growing pot grew smoothly because there was no planting damage. It is considered that the difference between the two has disappeared.
Comparative Example 1 having a film thickness of 200 μm and no addition of a bactericide had poor degradability from the time of transplantation to the final examination, and at any time,
Growth was poor. The degree of decomposition of the pot to which the fungicide was added was the same as that of the pot without the fungicide, and the addition of the fungicide suppressed the occurrence of mold and produced good results for the growth of seedlings.

Example 11 The same pot as that used in Example 3 was used for cutting and bud of chrysanthemum, and transplanted one month later. The strength until transplantation was sufficient, and the work efficiency at the time of transplantation was improved. The seedlings after transplanting grew smoothly, and no disease or chemical damage occurred.

Example 12 The same pot as that used in Example 6 was sowed with periwinkle seeds. One month later, excellent seedlings were obtained and transplanted.
The strength until transplantation was sufficient, and the work efficiency at the time of transplantation was good. There was no mold generation, and the seedlings grew smoothly and flowered even after transplantation. No illness or phytotoxicity occurred.

Examples 13 and 14 Types of Polymer Film Thickness Additive Additive (μm) (%) Example 13 Poly (3HB-3HV) 70 Activated Carbon 5.0 Example 14 Polycaprolactone 70 Carbon Black 5.0 Example Pots were prepared in the same manner as in Nos. 1 to 10, and morning glory seeds were sown on the prepared soil. One month later, excellent seedlings were obtained and transplanted. The strength until transplantation was sufficient, and the work efficiency at the time of transplantation was good. The occurrence of mold was small, and the seedlings grew smoothly and flowered even after transplantation. No illness or phytotoxicity occurred.

[0032]

The seedling raising pot of the present invention maintains sufficient strength from seeding to transplantation after the seedlings are grown, since the biodegradability is finely controlled after transplantation and does not adversely affect rooting. By using this, excellent seedlings can be obtained, and the seedlings grow well after transplantation. The work efficiency at the time of transplantation is improved, and the problems of work complexity and planting damage of the seedling are improved. In addition, by containing a fungicide in the material of the pot, the disease can be suppressed.

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Claims (4)

(57) [Claims] A film having a thickness of 50 to 200 μm and a diameter of 3 to 50 μm;
10cm or side is 3-10cm, height is 3-15c
seedling pot having a cylindrical or square shape in the range of m and made of a biodegradable aliphatic polyester compound or a modified product thereof. 2. The seedling raising pot according to claim 1, wherein the modified product is a polymer obtained by modifying an aliphatic polyester compound with 10% by weight or less of a diisocyanate compound. 3. The seedling pot according to claim 1, wherein a fungicide is contained in the material. 4. The seedling pot according to claim 1, wherein the material contains activated carbon and / or carbon black.