JPS6352827A - Algae controlling culture bed made of mineral fiber - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention A1 Object of the Invention [Field of Industrial Application] The present invention relates to an artificial culture medium for plant cultivation, and more specifically, a water-insoluble metal is added to at least the upper surface layer of a mineral fiber aggregate serving as an artificial culture medium. The purpose is to provide a cultivation bed in which harmful algae do not grow on the surface of the medium under cultivation conditions by attaching hydroxide.

(Prior art) Minerals such as rock wool, slag wool, glass wool, etc.
The use of IN accumulations as hydroponic cultivation beds for plants, especially vegetables, has already been widely practiced.

Mineral fiber aggregates are made by melting mineral and inorganic raw materials such as rocks and slag, blowing them away using centrifugal force and fumes, turning them into fibers, and depositing them on a net conveyor with spray adhesive! The cotton is laminated and collected, dried and cured to produce a mat shape, which is then cut into appropriate dimensions to produce artificial cultivation beds in the form of sheets or blocks.

When creating this artificial cultivation bed, modification treatments such as improving water absorption by treatment with a hydrophilic agent or adding and mixing fertilizer components are also carried out.

(Problem to be Solved by the Invention) In hydroponic cultivation using an artificial cultivation bed, it is desirable to ensure that the supplied nutrient solution is always kept at an appropriate level on the cultivation bed. The moist state of the nutrient solution is maintained, causing the growth and growth of green algae, which grow to cover the entire floor surface in a relatively short period of time, and then die and rot, leaving a surface layer that impairs ventilation and liquid permeability. There were problems such as formation, disease and insect damage, which deteriorated the cultivation conditions.

Conventionally, attempts have been made to prevent the generation and growth of algae by covering the surface of the cultivation bed with a light-shielding film or adding algaecides to the nutrient solution, but these efforts have been insufficiently effective. In the case of algaecides, they lacked practicality as they caused problems for the cultivated plants themselves.

Structure of the Invention (Means for Solving Problems) The present invention is based on the knowledge that extremely effective anti-algae properties can be obtained by allowing water-insoluble metal hydroxides to exist in the upper surface layer of the cultivation bed. It is complete.

That is, the gist of the present invention is an antifreeze mineral 41tIi jaw cultivation bed characterized by a small amount of mineral ll1II aggregates (both distributed in the upper surface layer and a reduced amount of water-insoluble metal hydroxide deposited), The insoluble metal hydroxide is precipitated and adhered to the surface of the constituent fibers by neutralization treatment of an aqueous metal salt solution applied to and impregnated in the mineral fiber aggregate, and the water-insoluble metal hydroxide in the above is copper hydroxide. This is an embodiment of the present invention.

The metal hydroxide used in the present invention only needs to be water-insoluble (
Generally, Cu, AI, Fe, Zn, Sn, and (7) hydroxides can be used because they have effective anti-algae properties and are harmless to cultivated plants, but copper hydroxide in particular has bactericidal properties and A1 is preferable because good effects can be obtained with a relatively small amount of use.
By increasing the amount of other metal hydroxides used, substantially the same algae-preventing effect can be obtained.

These metal hydroxides are simply mineral meii as fine powders.
Although it may be attached to the surface of the bulk surface, a more preferable cultivation bed can be obtained if it is used in combination with a hydrophilic adhesive to adhere to the surface of the constituent fibers.

However, the most effective attachment method is to apply a metal salt aqueous solution to the entire or at least the upper surface layer of the mineral fiber aggregate, impregnate it, and then neutralize it, so that the precipitated metal hydroxide is attached to the constituent aim surface. According to this method, a uniform and strong distributed adhesion state can be obtained without reducing the air and liquid permeability of the mineral fiber aggregate.

(Function) Although the mechanism of action of inhibiting the growth of algae such as green algae by the water-insoluble metal hydroxide attached to the upper surface layer of the mineral fiber cultivation bed of the present invention cannot be explained, the bactericidal properties of metals It is thought that the rR light-shielding effect of the hydroxide particle layer may have the effect of inhibiting the growth of gA@.

Therefore, the amount of adhesion is determined experimentally, but it was necessary that the amount of adhesion be about 10a+g or more per 100d of surface within a range of at least 11II11 from the upper surface of the mineral-like aS stack. Of course, with this level of adhesion concentration, minerals! It may be distributed and adhered to the entire fiber aggregate.

(Example) Twelve cube blocks with a side of 10 cm obtained by cutting rock wool (bulk specific gravity 80/m") were prepared, and copper sulfate, aluminum sulfate, and iron sulfate were each mixed at 1°3.5
% aqueous solution was sprayed onto the upper surface of the block using an air spray gun, and then impregnated with 5% calcium hydroxide.
An aqueous solution was sprayed to deposit each metal hydroxide in a layer of about 1 to 3 mm on the upper surface of the block, followed by washing with water and drying to obtain 12 test blocks.

Each block was mixed with culture medium (nitrogen 1100pp, phosphorus 30pp
After immersion in potassium 30 ppm+, potassium 30 ppm
Place the lower part in a culture solution vat with a liquid depth of 201I11, and add 0.05 (1 (fresh weight)) of green algae to the surface of the book.
was sprayed and cultured for 21 days from June 10, 1986 in a greenhouse with a culture solution temperature of 23±3°C and a room temperature of 2B±10°C, and the results shown in the table below were obtained.

As a comparative example, culture was performed using the same rock wool block as in the example and under the same conditions as in the example. Comparative Example 1)
The table below also shows the results of a similar culture test (Comparative Example 2) in which the surface of the green algae was covered with a black synthetic resin nonwoven fabric to shield it from light after it was destroyed in Comparative Example 1 (Comparative Example 2).

A B C Comparative example 1 ' 100 3
4 Examples Copper hydroxide Aluminum hydroxide Iron hydroxide A: Gold FA oxide adhesion amount (metal 111 (1/A block top area 100a/)B
: Green algae flourishing area percentage (%) C: Green algae 5PAD value* *Chlorophyll amount measurement value (Minolta Chlorophyll Meter) Furthermore, even after 50 days when the culture w1 period was further extended by about 30 days, the amount of copper hydroxide adhesion remained as shown in the above table. 32a+g or above, no algae growth was observed, and for aluminum hydroxide and iron hydroxide, the above table shows 126111 (for + hydroxide, the algae overgrowth area is 5
0% or less, and its 5PAD value was also 20 or less, indicating effective algae-proofing properties.

From the above culture test results, it is clear that the culture bed of the present invention, which has a water-insoluble metal hydroxide adhering surface layer, has an excellent effect of inhibiting the growth of green algae, especially in the case of copper hydroxide. A remarkable effect was obtained that could completely prevent the growth of green algae.

C1 Effects of the Invention As mentioned above, the cultivation bed made of algae-proof mineral fiber H of the present invention not only has the aeration and liquid permeability, shape retention, and corrosion resistance of the mineral fiber aggregate, but also has no adverse effects on cultivated plants. Good cultivation conditions can be maintained for a long period of time with effective algal growth prevention and growth suppressing effects, so not only Haginai but also flowers, 11! It is extremely excellent as a hydroponic artificial medium for seeding and raising seedlings of leaf plants, etc., and for transplanting hydroponics, and it is also extremely easy to introduce water-insoluble metal hydroxides, reducing the production cost of cultivation beds. is also very small.

Claims (1)

[Claims] 1), distributed in at least the upper surface layer of the mineral fiber aggregate,
A cultivation bed made of algae-proof mineral fiber, characterized by having a water-insoluble metal hydroxide attached thereto. 2) The anti-algae treatment according to claim 1, wherein the water-insoluble metal hydroxide is precipitated and adhered to the surface of the constituent fibers by neutralization treatment of an aqueous metal salt solution applied to and impregnated with the mineral fiber aggregate. Cultivation bed made of natural mineral fiber. 3) The algae-proof mineral fiber cultivation bed according to claim 1 or 2, wherein the water-insoluble metal hydroxide is copper hydroxide.