JPH0673412B2 - Plant culture medium material - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a novel medium material used for plant cultivation.

BACKGROUND OF THE INVENTION Conventionally, plants such as vegetables and flowers have been cultivated using natural soil, but with the recent development of managed agriculture, plants having certain characteristics instead of natural soil. Cultivation medium materials (hereinafter sometimes simply referred to as “medium materials”) are being used to grow in glass greenhouses and greenhouses under the control of appropriate conditions. As such a cultivation method, hydroponics, gravel cultivation, potted cultivation and the like are known.

The medium material used in such a cultivation method is required to be chemically stable so that substances harmful to the growth of the crop and the human body are not eluted, and further, the medium material is Since it is used for a long time in contact with water, it must be physically stable such that it will not disintegrate due to contact with water. Furthermore, this medium material is generally used repeatedly, and when it is reused, it is used after being washed or disinfected in order to prevent the occurrence of diseases of crops. Therefore, it is necessary that the medium material is one that can be easily washed and disinfected, and that is not physically or chemically changed by such an operation.

From this point of view, as the medium material, sand, pebbles, gravel, lightweight aggregate (light bone or commercial gravel), volcanic gravel and the like have been conventionally used.

However, among these medium materials, natural gravel such as sand, pebbles, and gravel tends to frequently change its chemical and physical properties because its composition is not constant depending on the collection place. Therefore, in order to adjust the soluble components in the gravel and remove the components harmful to the growth of the plant, they can often be used only after pretreatment, and in such a case, considerable labor and labor are required. The problem of cost and expense arises.

In addition, lightweight aggregates (light bones) and volcanic gravel are porous substances, and while used for cultivation, the pores of green algae (such as blue-green algae), pathogenic fungi, molds and microorganisms such as bacteria grow. There is a problem that it becomes a nest and the growth of the crop under cultivation is adversely affected. Further, as described above, the medium material having pores may not be able to completely remove the green algae or microorganisms present in the pores by disinfection and washing for each crop, and such a medium material that is incompletely washed and disinfected. When the continuous cropping is carried out by using, there is a problem that the amount of green algae generated increases as it is repeatedly used, and moreover, diseases are more likely to occur.

In addition, the collection of naturally produced medium materials is being restricted from the viewpoint of environmental damage.

On the other hand, in order to solve the problems of natural culture medium materials, proposals regarding artificial culture medium materials and manufacturing methods thereof have also been made (for example, Japanese Patent Publication Nos. 52-39736, 43-22209, and 43-2).
2210, 43-22211, 43-22212, etc.).

However, since the medium materials described in these publications are all porous, green algae and microorganisms are likely to be generated during use, and the problem that complete cleaning and disinfection is difficult is essential. Will not be resolved.

[Object of the Invention] The present invention aims to provide a novel plant cultivation medium material.

More specifically, the object of the present invention is to provide a novel plant cultivation medium material suitable as a medium material used in a cultivation method such as hydroponic cultivation, gravel cultivation and potted cultivation.

SUMMARY OF THE INVENTION The present invention is an amorphous residue discharged from a coal gasification furnace, having an SiO ₂ content of 65 wt% or less and an Al ₂ O ₃ content of 1% or less.
0% by weight or more, CaO content of 5% by weight or more, consisting of substantially pore-free amorphous particles, and the amount of the amorphous particles passing through a sieve having an opening of 0.60 mm is 20% by weight or less. The plant culture medium material is characterized in that

[Effect of the Invention] Since the medium material of the present invention is composed of amorphous particles having substantially no pores (micropores), the generation of green algae and microorganisms is small. Further, even when the product is reused after being washed and disinfected, green algae and microorganisms can be easily removed. Therefore, it is possible to effectively prevent the occurrence of green algae and diseases during continuous use.

Further, the medium material of the present invention has a good water-retaining property because it has a particle size in a specific range, and is used in various cultivation methods including hydroponic cultivation, gravel cultivation and potted cultivation. It has good properties as a culture medium material.

Furthermore, CaO contained in the medium material of the present invention is eluted by root acid or a culture solution, and has the action of adjusting the pH value of the crop growth environment.

Therefore, the yield of crops is increased by using the medium material of the present invention.

DETAILED DESCRIPTION OF THE INVENTION The medium material of the present invention, that is, the plant cultivation medium material, is an amorphous residue discharged from a coal gasification furnace, and is composed of SiO ₂ , Al ₂
It is composed of amorphous particles containing O ₃ and CaO as main components.

The contents of these components are SiO ₂ of 65% by weight or less (preferably 30 to 60% by weight), Al ₂ O ₃ of 10% by weight or more (preferably 20 to 40% by weight), and CaO. Is 5% by weight or more (preferably 10 to 30% by weight, particularly preferably 10 to 25% by weight). These three components are usually 85
It is contained by weight% or more (preferably 90% by weight or more).

Furthermore, the medium material of the present invention usually contains iron oxide, MgO, and alkali metal oxides (such as Na ₂ O and K ₂ O) in addition to the above three components. When containing these other components, the normal content of these other components is 1 to 15 iron oxides.
% By weight (based on Fe ₂ O ₃ ), 0.5 to 7% by weight of MgO, 0.5 to 7% by weight of alkali metal oxide (based on Na ₂ O), and may also contain a trace amount of TiO ₂ . The total content of these components is usually 15% by weight or less (preferably
10% by weight or less).

The medium material of the present invention is characteristically high in CaO content. Then, in the medium material of the present invention, this CaO not only acts as a component forming the medium material,
It has a function to elute a part of CaO and maintain the pH value in the neutral range. That is, plants, when absorbing nutrients from the soil, secrete root acid from the root to dissolve the sparingly soluble substance and absorb the nutrients, but at this time, the root acid is the medium material of the present invention. Part of CaO in the sample is eluted. The medium material of the present invention has a high CaO content, and has a high unit volume weight as will be described later, so that, for example, Ca per unit volume compared with a lightweight aggregate or the like which is usually used as a medium material.
The elution amount of O becomes very large. As a result, the amount of CaO eluted by the action of root acid or the like is usually 5 times or more as compared with the lightweight aggregate having the same capacity. CaO thus eluted is
It acts to maintain the growing soil environment of plants in the neutral range. Generally, when cultivating a crop, the pH value of the growing soil environment is preferably in a neutral range, and particularly when cultivating a crop vulnerable to an acidic soil such as lettuce, salad vegetables and spinach, the growth environment It is necessary to always maintain the pH value in the neutral range. Therefore, by using the medium material of the present invention, the growing environment does not become extremely acidic, and therefore the living weight of a crop vulnerable to the acidic soil as described above is increased, which works well for growing the crop. .

The action that the pH value of the medium material of the present invention can be adjusted to a neutral range is, for example, the medium material 1 of the present invention.
8.0 ml and 100 ml circulating at a circulation speed of about 100 ml / hour
It can be confirmed by contacting with a 2 wt% aqueous citric acid solution for about 150 hours and then measuring the pH value of the aqueous citric acid solution. That is, the pH value of the 2 wt% citric acid aqueous solution is 4.68, but when the medium material of the present invention and the citric acid aqueous solution are brought into contact with each other as described above, CaO and the like are eluted, so that the pH of this aqueous solution is Value is 6 ~
A value within the range of 7 is displayed.

Further, the CaO thus eluted acts not only to adjust the pH value as described above, but also a part thereof is absorbed in the crop and acts as an element component necessary for the growth of the crop.
Then, it was found that when the medium material of the present invention was used, CaO was absorbed better than when other medium materials were used. The detailed reason for this is unknown at present, but other components contained in the medium material of the present invention act to assist absorption of CaO, and CaO is eluted from a certain volume of the medium material of the present invention. Since there is a large amount of CaO, it is presumed that the two interact and CaO is well absorbed.

Then, CaO is similar to the dissolution and elution action by the above-mentioned root acid, since it is also eluted by a culture solution used in hydroponic cultivation, gravel cultivation and potted cultivation, by using the medium material of the present invention, It is possible to maintain the pH value of the culture solution in the neutral range. Moreover, this CaO is effectively absorbed by crops.

The culture medium material of the present invention has a unique composition as described above, but the particles are further amorphous, and the amorphous particles are characterized by having substantially no pores. Have That is, when the medium material of the present invention is observed, the particles have substantially no pores and the surface thereof is very smooth. Therefore, unlike the case of conventional hydroponic cultivation using a porous material, microorganisms and green algae are not generated with nests in the pores. Even when microorganisms and green algae are generated, it is presumed that the microorganisms and green algae are present so as to adhere to the surface of the amorphous particles that are the medium material of the present invention, and therefore their growth area Is narrower than the porous particles, and the surface of the particles is smooth, so that the amount thereof is small. In addition, since microorganisms and green algae existing in a state of being attached to the smooth surface of the particles can be easily removed by washing and disinfecting, the growth failure of the crop due to the generation of green algae during continuous cultivation and The occurrence of diseases can be effectively prevented. Furthermore, cleaning and disinfection can be performed in a short time and workability is good.

In addition, the medium material of the present invention has an advantage that the root surface is less likely to be damaged during a replanting crop because the particle surface is smooth as compared with a conventionally used medium material, particularly porous particles. ing. In particular, when the medium material of the present invention is used as a nursery medium material, the amount of the medium material attached to the roots of the seedlings at the time of replanting and planting is small, and the attached medium material can be extremely easily removed by washing with water. Therefore, the thin roots of the terminal part are not damaged, and the growth of the crop after planting is very good.

In the medium material of the present invention, the particle size contributes to adjustment of water retention of the medium material. That is, improving the water permeability,
To increase the amount of air between medium material particles, one with a relatively large particle size is selectively used, while when water retention is required, one with a relatively small particle size is selected and used. can do. A medium material having desired water retention and air content can be prepared by appropriately combining and using one having a large particle diameter and one having a small particle diameter.

Therefore, the culture medium material of the present invention is composed of amorphous particles having a weight of 20% by weight or less that has passed through a sieve having a 0.60 mm mesh. Furthermore, the weight of the passing particles is preferably 10% by weight or less. And, the medium material of the present invention usually has an opening of 4.75 mm.
The amorphous particles have a residual content (non-passage content) of 5% by weight or less (preferably 3% by weight or less). Amorphous particles having such a particle size can be further screened and mixed according to the type of cultivated crop. If the amount of passage through the openings of 0.60 mm is more than 20% by weight, in the case of hydroponics, for example, fine particles flow out into the culture solution, which causes troubles in the hydroponics device.

The unit volume weight of the culture medium material of the present invention is generally higher than the commonly used lightweight aggregates and porous materials such as lapilli. In order for crops to have self-supporting power,
It is necessary that this unit volume weight be somewhat high, and since the unit volume weight of the medium material of the present invention is usually within the range of 1.5 to 2.0 kg / l (preferably 1.5 to 1.8 kg / l), cultivation It becomes possible to give good self-supporting power to the crop.

The medium material of the present invention having such characteristics is produced by using the amorphous residue discharged from the gasification furnace whose main raw material is coal.

In detail, this amorphous residue is supplied as a residue generated when producing synthesis gas by partial oxidation of coal.
Examples of the method for producing synthesis gas include the Rurugi method, the Winkler method, the Copper's Toschek method and the Otto-Rumen method, and the KDV method, the Lulurgi sladding method, the Shinzan method, the WH method, the U gas method, the HYGAS method, Examples of coal gasification methods include coal technology research method, pressurized fluidized hydrogenation gasification method, hybrid method, HTW method, BIGAS method, Shell (Shell Coppers) method, Saalberg-Otto method, Sumitomo method and Texaco method. it can. Especially the Copper's Tocheck method,
Emissions from coal gasifiers such as the Otto-Rumen method, Lurugis sladding method, Shell (Shell Coppers) method and Texaco method that perform partial oxidation of coal in a gasifier at a temperature above the softening point of coal. It is preferable to use the residue.

For example, in the Texaco method, coal is charged as a water slurry into a coal gasification furnace, heated under pressure to a temperature above the softening point of the ash (generally 1300 to 1500 ° C), and partially oxidized. At this time, a molten or semi-molten residue is produced, and usually this residue is cooled with water or the like, then crushed if necessary, further classified, and discharged from the coal gasification furnace.

Coal gasification methods such as the Texaco method are described in detail in "Chemical Economy" August and September 1981.

The composition of the residue generated by partial oxidation of coal is somewhat different depending on the type of coal used as a raw material, but in the present invention, it is generated during partial oxidation of coal such as coal gasification regardless of the type of coal. The residue can be used. Examples of coal used include Canadian coal, Australian coal, American coal, South African coal and Chinese coal.

The residue thus discharged from the gasification furnace is amorphous.
Therefore, no specific peak is observed even when X-ray diffraction is performed.

Generally, the content of SiO _{2 in} the amorphous residue as described above is 65% by weight or less (preferably in the range of 30 to 60% by weight), and the content of Al ₂ O ₃ is 10% by weight or more (preferably 20 to 40%). %), And the CaO content is 5% by weight or more (preferably 10 to 30% by weight, particularly preferably 10 to 25% by weight), and usually a small amount of iron oxide, MgO, alkali metal oxide And TiO _{2 and the} like.

In addition, the absolute dry specific gravity of such amorphous residue is usually 2.3 to 3.0.
Within the g / cm ³ range.

The residue generated during such partial oxidation of coal is
Particularly useful applications have not been developed, and most are used for landfills. Therefore, the use of the above residue as a raw material of the culture medium material of the present invention achieves the purpose of providing a novel culture medium material as described above, and at the same time, effectively enables the industrial waste resource which has not been conventionally used effectively. It will provide a way to utilize.

The culture medium material of the present invention can be produced by pulverizing the amorphous residue discharged from such a coal gasification furnace or the like, and further classifying it. Then, by utilizing the amorphous residue discharged from the coal gasification furnace, since the amorphous residue is the one discharged by treating the coal at a very high temperature as described above, substantially microorganisms, Since it does not contain bacteria and pathogens, the medium material does not bring microorganisms, bacteria and pathogens into the culture solution. Further, it is possible to always supply a stable quality medium material with little variation in the composition of the components.

Further, since the above-mentioned amorphous residue is usually black, there is also an advantage that by using this, it effectively acts to maintain the temperature of the medium or the culture solution in the low temperature period from autumn to spring. Since the particles are usually glossy, they can be suitably used as a medium material for ornamental plants such as a medium material used in a transparent pot for gardening.

The culture medium material of the present invention can be used in the same manner as the culture medium material conventionally used as a culture medium material in various cultivation methods such as hydroponic cultivation, gravel cultivation and potted cultivation as described above.

The medium material of the present invention is preferably used by itself without being mixed with other medium materials, whereby the excellent characteristics of the medium material are sufficiently exhibited, and it is preferable that the characteristics of the medium material of the present invention are not impaired. It is also possible to use it by mixing it with the conventionally used medium materials such as sand, pebbles, gravel, lightweight aggregate and lapilli.

It can also be used as a modifier for the conventionally used culture medium material. For example, it can be used for applications such as adding a small amount of the medium material of the present invention to a lightweight medium material to adjust the unit volume weight.

Next, examples and comparative examples of the present invention will be shown.

[Example 1] Amorphous residue discharged from a coal gasifier was washed with water to obtain coarse particle residue, which was then classified using a sieve having an opening of 1.70 mm.
The fine particles that passed through the sieve were excluded, and the particles that did not pass through the sieve were used as the medium material.

The unit volume weight (measured by JIS-A1104) of the medium material used (that is, amorphous residue) was 1.63 g / cm ³ , and the absolute dry specific gravity (measured by JIS-A1135) was 2.59 g / cm ^3. It was Also,
Electron microscope (JXA-50A, JEOL Ltd.)
When the particles were observed at a magnification of 5,000 times, the surface of the particles was smooth, and no crystal precipitation or pores were observed.
Furthermore, the existence of crystals could not be confirmed from the result of X-ray diffraction.

The particle size distribution of the used culture medium material (amorphous residue particles) is shown in Table 1, and the chemical composition is shown in Table 2.

The culture medium materials used in the examples of the present invention are as described above.

The above medium materials are used for domestic hydroponic cultivation (Japan Aluminum Co., Ltd.)
Made in a vegetable cultivation bed and sowed with salad vegetables, radish (daikon radish) and spinach (forage grass) seeds, and hydroponically grown in a greenhouse using a standard culture solution (garden preparation). Cultivated (first work).

In the above hydroponic culture, salad vegetables, radishes and spinach, the seeding date is November 25, both from the seeding date
Harvested on day 43.

Incidentally. The component analysis was performed according to the method specified in JIS-M-8852.

[Comparative Example 1] In Example 1, a commercially available porous lightweight aggregate was washed with water instead of the amorphous residue particles as a medium material, and then particles having a particle diameter of less than 1 mm were excluded by sieving. Salad vegetables, radishes, and spinach were cultivated in the same manner except that was used (first crop).

The composition of the porous lightweight aggregate used is also shown in Table 2. The unit volume weight of this porous lightweight aggregate (commercially available product) is
The specific gravity was 0.85 g / cm ³ , and the absolute dry specific gravity was 1.30 g / cm ³ .

The biomass (yield) and yield ratio (relative biomass when the biomass harvested in Comparative Example 1 described below is 100) of the salad vegetables, radishes and spinach harvested in Example 1 and Comparative Example 1 are third. Shown in the table.

As is clear from Table 3 above, the crops hydroponically cultivated using the medium material of the present invention had a higher yield ratio (biological weight) than those cultivated using lightweight aggregate.

[Example 2] The medium material after cultivating the salad vegetables, radish and spinach in Example 1 was thoroughly washed and used as the medium material for hydroponics, and the same procedure as in Example 1 was performed. Hydroponics was performed (second crop).

The seeding date for radish and leek is January 9th. However, the radish was harvested 35 days after the seeding date, and the leek was harvested 44 days after the seeding date.

[Comparative Example 2] Radish and leeks were prepared in the same manner as in Example 2 except that the lightweight aggregate after cultivating salad vegetables, radish and spinach in Comparative Example 1 was thoroughly washed and used as a medium material for hydroponics. Was hydroponically grown (second crop).

Table 4 shows the germination rate, fresh weight, yield ratio (relative value when the biomass harvested in Comparative Example 2 is 100) and the occurrence of green algae of radishes and leeks cultivated in Example 2 and Comparative Example 2. Show.

As is clear from Table 4 above, in Example 2, the generation of green algae was small, and the germination rate and growth were good. On the other hand, in Comparative Example 2, a large amount of green algae was generated, and thus the germination rate was low and the growth was poor.

[Example 3] In Example 2, the medium material after cultivating the radish and leeks was thoroughly washed and used as the medium material for hydroponic cultivation, and in the same manner as in Example 2, hydroponic cultivation of the radish was performed. Was performed (the third work).

The seeding date of the radish was February 27, and 25 days after that, it was harvested.

[Comparative Example 3] In Comparative Example 2, the lightweight aggregate after cultivating radish and leeks was thoroughly washed and used as a medium material for hydroponic culture, and hydroponics of radish was carried out in the same manner as in Example 3. Cultivated (third crop).

Table 5 shows the fresh weight of the radishes harvested in Example 3 and Comparative Example 3 and the occurrence of green algae 4 days, 10 days and 14 days after the seeding.

As is clear from Table 5 above, when the medium material of the present invention is used, even if the medium material is continuously used, it is possible to easily remove the green algae and the like adhering to the surface of the particles by washing. Occurrence can be suppressed. In contrast, the lightweight aggregate used in the comparative example is presumed to have insufficient cleaning in the micropores because it has micropores,
Therefore, as the number of times of use increased, green algae began to be generated at an early stage, and the amount of generation was significantly increased.

The effects of such generation of green algae are prominently manifested as a decrease in the number of radishes harvested (due to a lower germination rate) and a lower fresh weight.

[Example 4] The amorphous residue particles used in Example 1 were mixed with a fixed volume (18.0 ml,
29 g), and this was filled in a small permeable tube (glass filter).

Separately, 100 ml of a 2 wt% citric acid aqueous solution (pH value 4.56) was prepared, and this aqueous solution was mixed with the amorphous residue particles filled in the test tube for 167 hours at a circulation rate of 103 ml / hour with a circulation rate of 103 ml / hour. Contacted.

The pH value of the citric acid aqueous solution after 167 hours and the amounts of CaO and MgO eluted in the aqueous solution were measured.

[Comparative Example 4] A pH value of an aqueous citric acid solution was obtained in the same manner as in Example 4 except that the same amount (18.0 ml, 16 g) of the lightweight aggregate used in Example 1 was used instead of the amorphous residue particles. In addition, the amounts of CaO and MgO eluted in this aqueous solution were measured.

The measurement results in Example 4 and Comparative Example 4 are shown in Table 6.

As is clear from Table 6, when the same volume is used, CaO and M of the amorphous residue particles used as the medium material of the present invention.
The elution amount of gO was larger when CaO and MgO were used when the lightweight aggregate was used. Therefore, the pH value of the citric acid aqueous solution was increased due to the difference in the elution amount.

In Example 5 Example 4, in place of 2 wt% aqueous solution of citric acid, the formulation of hydroponic fertilizer _{(NP 2 O 3 -K 2 O} -MgO-MnO-B 2 O 3 ratio:
10-7-28-4-0.1-0.1, Ube Industries, Ltd., trade name: Ube hydroponic fertilizer No. 1) 0.1 wt% aqueous solution (pH value: 5.2) was used, and the circulation time was 254 hours. Except for the above, the changes in pH value of the above aqueous solution due to the elution of components such as CaO were examined in the same manner.

[Comparative Example 5] In Example 5, except that the lightweight aggregate used in Comparative Example 1 was used instead of the amorphous residue, the variation of the pH value of the aqueous solution due to the elution of the components such as CaO was similarly performed. Examined.

The results in Example 5 and Comparative Example 5 are shown in Table 7.

As is clear from Table 7, even when an aqueous solution of hydroponic fertilizer was used instead of the aqueous solution of citric acid, a similar tendency was observed in the action of adjusting the pH value of the aqueous solution by elution of CaO and the like.

[Example 6] The amorphous residue particles used in Example 1 were closed at the bottom with a / 5000.
Fill the Wagner pot. A standard culture solution (EC2.4) prepared from the hydroponic fertilizer (Ube hydroponic fertilizer No. 1) and lime nitrate (Ube hydroponic fertilizer No. 2) described in Example 5 by planting lettuce seedlings in this Wagner pot. Once a day, fill the Wagner pot to fill it up and
Left for hours. After 1 hour, the bottom plug was removed and the aqueous solution was discharged.

The above-mentioned injection and discharge operations were repeated to cultivate lettuce pebbles.

The lettuce cultivation period is from February 4 to March 10.
In addition, the cultivation was repeated twice using a Wagner pot.

[Comparative Example 6] In Example 6, instead of the amorphous residue particles, Comparative Example 1
The lettuce pebbles were cultivated in the same manner except that the lightweight aggregate used in 1. was used.

Comparative Example 7 In Example 6, instead of the amorphous residue particles, silica sand (average particle diameter: 3.2 mm, unit volume weight: 1.65 g / cm ³ , CaO content rate:
The lettuce was cultivated in the same manner except that 0.8% by weight) was used.

Table 8 shows the growth amount of lettuce grown by gravel cultivation in Example 6 and Comparative Examples 6 and 7 per Wagner pot, the content rate of calcium components in the lettuce (calculated as CaO), and the green algae generation status. Note that the growth amount and the content rate of the calcium component are the average values of two consecutive lettuce harvested.

As is clear from Table 8, the amorphous residue particles can be favorably used as a medium material in cultivating pebbles. That is, the amount of lettuce grown by pebbles cultivation using the medium material of the present invention was larger than that of pebbles cultivation using lightweight aggregate and silica sand. Further, the problem that a large amount of green algae is generated, which is a problem when using the lightweight aggregate, has been solved. Furthermore, the calcium component eluted in the culture solution is
It was well absorbed in the cultivated lettuce.

[Example 7] The amorphous residue particles used in Example 1 were placed in a nursery pot having a hole in the bottom, and seeds of tomato, lettuce and cucumber were sown, and the pot was then fed with standard liquid fertilizer (1/4 concentration). Were placed in a shallowly stretched pat and germinated in a glass greenhouse.
The seeding date is December 15.

Comparative Example 9 Tomatoes, lettuce and cucumber were raised in the same manner as in Example 7 except that the lightweight aggregate used in Comparative Example 1 was used instead of the amorphous residue particles.

Comparative Example 10 Tomatoes, lettuce and cucumber were raised in the same manner as in Example 7 except that field soil (soil using granite as a base material (sand loam soil)) was used in place of the amorphous residue particles. I did.

Table 9 shows the living body weight ratios of the seedlings raised in Example 7 and Comparative Examples 9 and 10 described above. In addition, in Table 9, the living body weight ratio is expressed by setting the living body weight of seedlings obtained by cultivating each crop in Comparative Example 10 (field soil) to 100%.

However, tomato is the weight ratio of the seedlings 45 days after sowing, lettuce is the weight ratio of the seeds after 25 days, and cucumber is the weight ratio of the seeds after 30 days.

As is clear from Table 9, by using the medium material of the present invention, seedlings grow well in tomato, lettuce and cucumber. Furthermore, when measuring the fresh weight of crops, it is necessary to wash away the medium material attached to the roots, but seedlings raised using the medium material of the present invention are most easily washed with water. The material could be removed.

Therefore, when planting seedlings of crops in hydroponic beds,
The time required for washing with water could be shortened, and the roots were less damaged.

Claims (3)

[Claims] 1. An amorphous residue discharged from a coal gasification furnace, wherein the content of SiO ₂ is 65% by weight or less, the content of Al ₂ O ₃ is 10% by weight or more, and the content of CaO is A plant cultivation medium comprising 5% by weight or more of substantially pore-free amorphous particles, and the amount of the amorphous particles passing through a sieve having an opening of 0.60 mm is 20% by weight or less. material. 2. The plant culture medium material according to claim 1, wherein the residual amount of the amorphous particles on a sieve having an opening of 4.75 mm is 5% by weight or less. 3. The unit volume weight of the plant cultivation medium material is 1.
The plant cultivation medium material according to claim 1, which is in the range of 5 to 2.0 kg / l.