JPH01252233A - Culture medium material for growing plant - Google Patents

Abstract

PURPOSE:To obtain the title culture medium material improved in diffusivity of aqueous liquids such as water and other liquid fertilizers, capable of favorable growing rooting zone, by providing an aqueous liquid-diffusive sheet layer between forms made of inorganic fiber. CONSTITUTION:The objective culture medium material can be obtained by providing an aqueous liquid-diffusive sheet layer 3 between forms 1 and 2 each made of inorganic fiber such as rock wool, glass-wool or ceramic fiber. This culture medium material may, if needed, be incorporated with a hydrophilicity- imparting agent (e.g., alkylpolyoxyethylene ether), pH adjustor, fertilizer, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a culture medium for growing plants, and particularly to a culture medium for growing plants made of inorganic fibers that has improved diffusibility of aqueous liquids such as water and liquid fertilizer.

[Conventional technology]

Until now, natural soil or its granulated forms have often been used as plant growing media, but on the other hand, culture media based on industrially mass-produced artificial materials have also been developed. ing.

As such artificial medium-based culture medium, it is known that in addition to calcined minerals such as vermiculite and perlite, inorganic fibers such as rock wool are used (Japanese Patent Publication No. 41-12,
Publication No. 642). The invention primarily aims at improving soil quality by mixing inorganic fibers into clay soil to increase its ability to adsorb and retain water. Recently, rock wool hydroponics, which uses rock wool molded medium material made by processing rock wool, which is a type of inorganic fiber, into cloaks, cubes, boats, etc., has been attracting attention. Such rock wool molding medium material is made by molding rock wool with a polymer binder such as water-soluble phenol resin or melamine resin, and contains a hydrophilicity imparting agent, a pH adjusting agent, and a roughing agent as necessary. It is.

[Problem to be solved by the invention]

Rockwool hydroponics uses water and rockwool molding medium.
An aqueous liquid such as liquid fertilizer is used by sprinkling or dripping regularly or irregularly, and the aqueous liquid is diffused through the capillary voids formed between the rock wool fibers. However, since the rock wool molding medium material has one-dimensional or two-dimensional fiber orientation, it has the disadvantage that the direction of diffusion of the aqueous liquid is deflected, resulting in areas where the aqueous liquid does not circulate.

An object of the present invention is to provide a plant growing medium material made of inorganic fibers that has improved diffusibility of aqueous liquids such as water and liquid fertilizer.

[Means to solve the problem]

That is, the present invention is a plant growing medium material comprising an aqueous liquid diffusion sheet layer arranged in the middle of an inorganic fiber molded article.

The present invention will be explained in detail below.

Examples of the inorganic fibers used in the present invention include rock wool, glass wool, ceramic fiber, etc., and in particular, blast furnace slag and/or
Or, for example, rock wool rock wool made by melting natural rocks such as basalt, andesite, and diabase in a cupola, electric furnace, etc. and blowing them using centrifugal force and/or fluid pressure such as air or water vapor to make fibers.
(also called slag wool or mineral wool) can be used successfully.

Inorganic fibers such as rock wool are fiber aggregates in which fibers are deposited in layers, and in order to form them into cloaks, cubes, and boards, the fibers are partially bonded using a polymer binder. Examples of the polymeric binder include thermosetting resins such as phenol resins, melamine resins, and urea resins, and thermoplastic resins such as acrylic resins and vinyl acetate resins. Resins are preferred. The amount of polymer binder used is 0.5 to inorganic fiber.
5% by weight, preferably 1 to 3% by weight.

If a large amount of polymeric binder is used, the medium material becomes hard and has increased strength, but it tends to cause poor rooting.

On the other hand, if there is too little, the bonding strength between the fibers will be insufficient, causing them to come apart during processing or crumble when lifted.

In the present invention, the diffusion sheet that forms the aqueous liquid diffusion layer provided between the inorganic fiber molded articles may be made of, for example, natural fibers such as cotton and linen, recycled fibers such as rayon, and/or polypropylene, nylon, polyester, etc. Examples include cheesecloth made by regularly arranging synthetic fibers using an adhesive, heat and pressure, and nonwoven fabrics made by arranging these fibers irregularly or entangling them. It is best to select a diffusion sheet that has a good opening between fibers and a thickness that provides good root coverage.

It is important that the diffusion sheet is placed in the middle of the medium material, and it is particularly preferable to place it in the upper half of the medium material in the thickness direction. If it is placed on the upper end surface or lower layer of the culture medium, the diffusion effect of the aqueous liquid will be halved. The diffusion sheet may be simply inserted between the two divided medium materials, or may be adhered with a suitable adhesive. Although it is sufficient to arrange the diffusion sheets in one layer, two or more layers may be provided as necessary.

The culture medium of the present invention may contain various additives, such as hydrophilicity imparting agents, pH adjusters, fertilizers, etc., as necessary. Examples of the hydrophilicity imparting agent include alkyl polyoxyethylene ether, alkylphenyl polyoxyethylene ether, alkyl carbonyloxy polyethylene, N,N-di(polyoxyethylene)alkanamide,
Fatty acid polyhydric alcohol ester, fatty acid polyhydric alcohol polyoxyethylene ether, fatty acid sucrose ester,
Fatty acid monoglyceride', N, N-di(alkanol)
Nonionic surfactants such as alkanamides, such as ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, glycerin, butanetriol, polyethylene glycol , polypropylene glycol, polybutylene glycol, diglycerin, and the like. The amount of these hydrophilicity imparting agents used is 0.05 to 5% by weight, preferably 0.3 to 1% by weight based on the inorganic fiber.
Weight % is appropriate. If it is less than 0.05% by weight, there is no effect, and if it exceeds 5% by weight, there is no improvement in hydrophilicity.
Economic efficiency decreases.

In addition, inorganic fibers such as rock wool contain alkaline components such as calcium and magnesium, and when soaked in water, the pH of the soaking water increases, making it suitable as a substrate for culture medium for plants that prefer neutral or slightly acidic conditions. It is preferable to add a pH adjuster. Examples of pH adjusters include mineral acids such as sulfuric acid, hydrochloric acid, nitric acid, and phosphoric acid, or their ammonium salts, organic acids such as acetic acid, citric acid, tartaric acid, humic acid, and nitrofumic acid, natural minerals such as zeolite, and peat moss. Examples include humus soil, etc.

Furthermore, it is preferable to add fertilizer to the use of the medium material, for example, pine 1 for raising rice seedlings and medium material for home gardening. As fertilizers, examples of nitrogen fertilizers include ammonium sulfate, ammonium chloride, ammonium nitrate, urea, etc., examples of potassium fertilizers include potassium sulfate, potassium chloride, etc., and examples of phosphate fertilizers include lime superphosphate, ammonium phosphate, etc. etc. can be mentioned. These fertilizers may be single or compound fertilizers. The amount of fertilizer to be mixed is appropriately determined depending on the use of the culture medium.

The density of the culture medium of the present invention is appropriately selected depending on the use, and is usually 50 to 250 kg/m3, preferably 70 to 150 kg/m3.
g/m" is preferable. If it is less than 50 kg/m", the balance between water retention and air permeability is poor, and plant growth is poor. 250
If it exceeds kg/m3, the germination rate will decrease. The shape of the culture medium can be formed into any shape such as a mat, cube, or board. Since the fibers of the culture medium substrate formed in this manner are oriented in the lateral direction of the substrate, if the board is used as a head for growing plants, the substrate may be manufactured with the lateral fibers as they are. However, in mats for raising rice seedlings and cubes for raising seedlings and growing, it is necessary to improve the penetration of the roots. If you cut the horizontal fiber base material to an appropriate thickness and lay it out 90 degrees, the orientation of the fibers will be vertical, so if necessary, you can paste it on paper to use it as a vertical fiber base material. Can be done. The culture medium material may be incised or covered with a plastic film such as black polyester or silver polyurethane, if necessary.

[For production]

The culture medium of the present invention has a diffusion sheet layer for an aqueous liquid such as water or liquid fertilizer in the middle of the culture medium, so that the aqueous liquid infiltrated from the upper end surface of the culture medium in the direction of the line of gravity is absorbed into the capillary voids of the diffusion sheet itself. It is thought that the aqueous liquid is diffused in a direction perpendicular to the line of gravity through the capillary voids formed between the medium material base material and the diffusion sheet, and the diffusion volume of the aqueous liquid is expanded.

〔Example〕

Water-soluble phenol resin (2% solid content based on rock wool) is used as a polymeric binder, and polyoxyethylene nonylphenyl ether (0.5% by weight based on rock wool) is used as a hydrophilicity imparting agent. A mixture of a polymeric binder and a hydrophilicity imparting agent is sprayed onto the
The water-soluble phenol resin was cured by heating to ℃ to produce a base material. This base material is made of vertical fibers with a length of 10 cm and a width of 10 cm.
, was processed into a cube with a height of 5 cIll, divided into two parts 1 and 2 in the height direction, and as shown in Figure 1, plant growing medium material A with rayon cheesecloth 3 sandwiched between them. Manufactured. In addition, a plant growth medium material B was produced in which a nonwoven fabric 3 made of rayon was sandwiched in place of the cheesecloth 3 made of rayon.

For comparison, vertical fibers are 10 cm long, 10 cm wide, and 5 cm high.
Medium material C, which is simply processed into cubes of cm, and medium material E, which is made by overlapping rayon cheesecloth on the two end faces of C, and medium material E, which is made by overlapping rayon nonwoven fabric, are simply divided into two in the height direction. Culture medium material F without sandwiching the diffusion sheet was manufactured.

Next, an aqueous liquid diffusion test was conducted on these culture medium materials.

After sufficiently impregnating each culture medium with an aqueous solution consisting of 250 ml of 0.01N saline, 1.1% dextrin, 15 ml, 5 ml of 0.1% nioxin, and 525 ml of pure water,
% silver nitrate aqueous solution was dripped in 25 ml over 15 minutes. 110
Cut the medium material dried at ℃ for 15 hours at intervals of 8 to 10 m11, integrate the blackened parts (diffused parts of 0°01N silver nitrate aqueous solution), and superimpose them to calculate the diffusion volume of the aqueous liquid. I asked for it. The results are listed in Table 1.

Table 1 Diffusion test results for various culture medium materials [Effects of the invention] The plant growth medium material of the present invention described above has a diffusion sheet 1 perpendicular to the direction of flow of aqueous liquids such as water and liquid fertilizer (perpendicular to the line of gravity).
By disposing ~, the diffusion of the aqueous liquid is significantly improved, and the growth of the rhizosphere can be performed favorably.

[Brief explanation of the drawing]

FIG. 1 is a perspective view M showing a plant growing medium material provided with an aqueous liquid diffusion sheet layer according to an embodiment of the present invention. 1.2- Rock wool culture medium base material divided into two in the height direction, 3------- Diffusion sheet

Claims (1)

[Claims] A plant growing medium material comprising an inorganic fiber molded body and an aqueous liquid diffusion sheet layer arranged in the middle.