JP2726622B2 - Artificial soil composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soil composition containing bacterial cellulose, which is useful for stably retaining and growing seeds and plants.

[0002]

BACKGROUND OF THE INVENTION Soil is a natural composition that mechanically supports seeds and plants and supplies them with water, nutrients, oxygen and the like.
These are also called natural soils.

[0003] In general, it is recommended to use a sterilized and disinfected natural soil for plant cultivation. because,
This is because there is a possibility that germination and rooting of seeds and growth of a plant body may be inhibited by germs breeding in the soil.

[0004] However, the operation of disinfection requires a large amount of labor and cost, and the remaining disinfectant also has an adverse effect on the growth of plants, the environment, and the like.

[0005] In addition, weeds and parasitic roots in the soil, which are not killed by these disinfections, also have an adverse effect on cultivated plants.

Furthermore, natural soil is easy to dry, and maintaining a suitable wet state for seeds and plants (moisture management) also requires a great deal of labor and cost.

[0007] In the cultivation of plants outdoors, seeds and seeds may vary depending on soil properties such as water retention, drainage and drainage, and location conditions such as the slope of the soil, wind contact with the soil and rainfall. Possibility of plant establishment is low. This is due to phenomena such as seeds and plants flowing out and scattering with earth and sand or rainwater.

In such a case, the particle size, specific gravity, and composition of the soil component are appropriately selected according to the location conditions of the soil and used for cultivation, but no satisfactory results have been obtained.

From the above, replacement of natural soil with artificial soil has been studied.

Conventional artificial soils include foams, sponges, sponges, nonwoven fabrics, woven fabrics, fiber masses, sintered bodies, resin particles, and short fibers made of a polymer material. And the labor required for water management during cultivation.

Further, many of these artificial soils are made of non-biodegradable substances, and it is not preferable to spray the soil on the ground surface from the viewpoint of environmental protection. Similarly, the soil was cultivated using the soil. When transplanting a plant to the ground, it was necessary to separate the soil from the plant.

[0012] These plant isolation operations have damaged the roots of the plants and have resulted in poor colonization rates after transplantation.

[0013] The present inventors have considered such a problem and
"High water retention of the substrate", "Stably hold the seeds,
Stable support of the plant "," Smoothly stretch the roots of the plant, and stably supply water, nutrients, oxygen, etc. " As a result of intensive studies on the development of an artificial soil composition that satisfies the condition of being compatible (being biodegradable), the three-dimensional structure of the bacterial cellulose network enables seeds to be stably retained and high water retention. The present invention was found to be expressed and good root elongation was obtained, and the present invention was completed.

[0014]

That is, the present invention is an artificial soil composition comprising bacterial cellulose.

[0015] The bacterial cellulose referred to in the present invention is:
It is a cellulosic substance (hereinafter referred to as "bacterial cellulose") produced by culturing a microorganism belonging to the genus Acetobacter and having a cellulosic substance-producing ability.

The culturing can be performed by the method reported by the present inventors (for example, the method described in Japanese Patent Application No. 5-331149).

That is, a microorganism belonging to the genus Acetobacter or the like and having bacterial cellulose-producing ability is cultured aerobically,
By adding a carbon source or the like continuously or intermittently, the microorganism produces bacterial cellulose having a network structure of ribbon-like fibrils.

The microorganism to be used may be any microorganism as long as it is a microorganism capable of producing bacterial cellulose, and more specifically, a microorganism of the genus Acetobacter or Ag.
genus Robacterium, Rhizobium, S
genus arcina, genus Pseudomonas, Achr
genus omobacter, genus Alcaligenes, A
genus erobacter, genus Azotobacter, Z
Examples include bacteria and algae belonging to the genus oogle.
Among these, acetic acid bacteria are preferable.
bacter sp. BPR2001 (FERM BP
-4545), Acetobacter xylinu
m ATCC10245, ATCC23768, ATC
C23769, ATCC14851, ATCC1114
2, and ATCC 10821, more preferably B
PR2001 strain (FERM BP-4545) and AT
CC10245 strain.

The carbon sources used for the culture include sucrose, glucose, gluconic acid, fructose, mannitol, sorbitol, galactose, maltose, erythrit, cadonito, glycerin, ethylene glycol, propylene glycol, ethanol, propanol, butanol, acetic acid, Butyric acid, valeric acid and the like are used alone or in combination. Furthermore, starch hydrolyzate, citrus molasses, beet molasses, beet juice, sugarcane juice, fruit juices including citrus fruits and the like containing these can be used.

At the time of culturing, these carbon sources can be continuously or intermittently supplied to the culture solution.

Examples of the nitrogen source include ammonium salts such as ammonium sulfate, ammonium chloride and ammonium phosphate, and organic or inorganic nitrogen compounds such as nitrate, urea and peptone.

As the inorganic salts, phosphates, magnesium salts, calcium salts, iron salts, manganese salts, cobalt salts, molybdates, red blood salts, chelating metals and the like are used.

When an auxotrophic mutant that requires an amino acid or the like for its growth is used, it is necessary to supplement the required organic nitrogen nutrient.

As the organic trace nutrients, amino acids, vitamins, fatty acids, nucleic acids, and peptone, casamino acid, yeast extract, soybean and the like containing these substances can be used.

The cultivation can be carried out at a temperature in the range of 10-50 ° C.

The pH during the culture can be used as long as it is within the range of 3-7. When adjusting the pH,
Any alkali and acid can be used. For example, alkalis such as sodium hydroxide, potassium hydroxide, and sodium carbonate, and acetic acid, citric acid, hydrochloric acid,
Acids such as sulfuric acid and nitric acid can be used.

[0027] The culture method may be any of static culture, aeration-agitation culture and shaking culture.

In the case of static culture, pellicle-like (gel-like) bacterial cellulose is obtained, and in the case of aeration-agitation culture or shaking culture, particles and fibrous bacterial cellulose are obtained. Can be

It is preferable to supply oxygen at a concentration suitable for the microorganism used. For example, oxygen is supplied into the culture as air having an oxygen concentration of 5 to 100%.

The supply amount may be any condition as long as the culture of the microorganism is not hindered.

When the bacterial cellulose produced by this method is isolated, washing with water, dehydration under pressure, washing with a dilute acid, washing with an alkali, treatment with an organic solvent, bleaching agents such as sodium hypochlorite and hydrogen peroxide, etc. , Lysozyme and other cell lysing enzymes, sodium lauryl sulfate, deoxycholic acid and other surfactants, and heating and washing in the range of room temperature to 200 ° C., alone or in combination. Can remove impurities.

Further, depending on the purpose of use, the bacterial cellulose may be used as it is without removing impurities of the bacterial cellulose after completion of the culture.

The bacterial cellulose referred to in the present invention may be a single substance composed of only cellulose, or may contain other polysaccharides, for example, those containing a heteropolysaccharide having β-1,4 as a main chain, and β-1,4. Those containing glucans such as 3 and β-1, 2 may be mixed together by hydrogen bonding or the like. The constituent components other than glucose in the case of the heteropolysaccharide are hexoses such as mannose, fructose, galactose, xylose, arabinose, rhamnose, and glucuronic acid, pentoses, and organic acids.

The bacterial cellulose thus obtained forms a network-like three-dimensional microfibril structure,
Very high water retention.

[0035] The soil composition of the present invention comprising these bacterial celluloses can be germinated and rooted by supplying moisture while stably maintaining the seeds in the composition. Also, with respect to the plant, the root is entangled with the bacterial cellulose fibers in the composition, so that the plant adheres to the composition (stably supports), and supplies water, nutrients, oxygen, etc. stably. While growing.

These can be carried out by sowing seeds (in the composition) or directly transplanting a plant or a part thereof (stems, buds, leaves and roots) in the same manner as in ordinary cultivation.

Further, the composition of the present invention can be used for water,
It can also be used for the main purpose of supplying nutrients and oxygen, and these embodiments are also included in the scope of the present invention.

[0038] In these embodiments, for example, the composition of the present invention is used as a support for growing grass in a golf course, and water, nutrients and oxygen are supplied. Supporting, supplying water, nutrients and oxygen by the composition of the present invention, and covering the cut end of the stem of a plant in a bouquet with the composition of the present invention to supply water, nutrients and oxygen, and the like. , But not limited thereto.

In the artificial soil composition of the present invention, the bacterial cellulose produced by the microorganism as described above may be used as it is. However, by further performing a defibration treatment to loosen the entanglement between the fibers, In some cases, the effects of the present invention can be enhanced.

The defibration treatment is carried out by adding pellicle-shaped (gel-like) bacterial cellulose obtained by a static culture method or particulate or fibrous bacterial cellulose obtained by an aeration stirring culture method or a shaking culture method to a state containing water. It can be performed by mechanical shearing force using a rotary disintegrator, a mixer, a homogenizer, or the like.

The bacterial cellulose used in the soil composition of the present invention has been described above, but the composition of the present invention may further contain a fertilizer.

Any of these fertilizers that can promote seed germination / rooting and plant growth can be used, such as nitrogen fertilizer, phosphate fertilizer and potassium fertilizer.

Further, the composition of the present invention may contain a microorganism having a bacterial cellulose-producing ability and a medium.

In these compositions, the microorganisms produce bacterial cellulose and the bacterial cellulose fibril-like fibers holding or supporting the seeds and plants can further grow.

Plants can be more firmly supported by the growth of bacterial cellulose fibers.

The microorganisms contained in the composition of the present invention include:
Any microorganism may be used as long as it is a microorganism capable of producing bacterial cellulose as described above.

The amount of the microorganism to be contained is as follows:
10 ⁰ to 10 ¹⁰ cells per mL, preferably 10
³ to 10 ⁸ cells.

As the medium to be contained, an ordinary medium can be used.

Furthermore, the composition of the present invention can contain any coloring agent, physiologically active substance, plant hormone, and the like.

Examples of the colorant include cellulose dyes such as Congo Red.

The composition of the present invention containing a coloring agent has excellent aesthetic appearance and is suitable for cultivation of a plant for indoor ornamental use.

Examples of the physiologically active substance and plant hormone include sibberellin, auxin, β-indoleacetic acid and the like, and the composition of the present invention containing these can grow plants more favorably.

The amount of bacterial cellulose contained in the composition of the present invention is 0.01% to 100%, preferably 0.05% to 30%, more preferably 0.1% to 100% in the composition. 15%.

The above-mentioned amounts will be appropriately set by those skilled in the art in consideration of the types of seeds and plants to be retained, cultivation conditions, location conditions, and the like.

The composition of the present invention can be used for both indoor cultivation and outdoor cultivation.

In indoor cultivation, Japanese radish,
It can be suitably used in cultivation of vegetables, flowers, seedlings, etc. such as honeysuckers and cherry tomatoes, and can be transplanted with the composition as it is after cultivation.

The implanted composition of the present invention is degraded by microorganisms and does not adversely affect the environment.

In outdoor cultivation, it can be used in the same manner as natural soil or the earth, but in particular, soil under conditions where the seed and plant establishment rate is low (sloping soil, strong windy soil and soil with high rainfall). Etc.) By coating the surface with the composition of the present invention, stable plant cultivation becomes possible.

In order to coat the soil surface with the composition of the present invention, for example, the composition of the present invention may be directly laid as a sheet, spread on the soil surface, or prepared to have a low viscosity. It can be performed by a method such as spraying things.

The coating layer of the composition of the present invention formed on the surface of the soil can stably hold the seed until germination and rooting, and can stably support and grow the plant until it is sufficiently rooted in the soil. .

These coating layers also have the effect of preventing the drying of the soil surface and the outflow and scattering of soil surface particles, and are gradually decomposed and dissolved by the action of microorganisms, light, rain and the like.

The conditions for forming these coating layers on the soil surface may be appropriately set by those skilled in the art in consideration of the amount and type of seeds and plants to be cultivated, the location conditions of the soil, and the like.

Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.

[0064]

【Example】

(Example 1) Soil area 5 on a house roof with a slope of 40%
A cultivation bed having a size of 0 cm × 50 cm was set up and filled with Kanuma soil so as to be parallel to the inclination of the roof.

3 g (dry weight) of bacterial cellulose and 500 alfalfa seeds, which had been defibrated by a rotary mixer, were suspended in 1 L of water to prepare a composition of the present invention. This composition was sprayed on the soil surface to form a coating layer. The germination rate was observed two weeks later, and the growth was measured one month later. Simply add 500 alfalfa seeds to water 1
The germination rate and growth rate were measured in the same manner using the suspension in L as a blank.

However, these two cultivation beds are arranged side by side so as to be in contact with each other, and there is no difference in conditions of sunshine time, rainfall and the like. The experiment was conducted in Kawasaki City, Kanagawa Prefecture in early April. Table 1 shows the results.

[0067]

[Table 1]

From the results shown in Table 1, the composition of the present invention stably retained seeds and germinated them even on sloped land.
In addition, the support after germination was excellent, and good growth was obtained.

Example 2 A bacterial cellulose pellicle obtained by stationary culture of a microorganism belonging to the genus Acetobacter or the like was washed, and the composition of the present invention containing 0.6% (% by weight) of bacterial cellulose was washed. Obtained. The composition was placed on the bottom of a plastic container having a diameter of 9 cm and a height of 15 cm, and water was added from above to sufficiently impregnate the composition with water, and then excess water was removed. This is cultivation bed A. However, the composition was 3.0 m in a plastic container.
It was used in such an amount as to have a thickness of m or 10.0 mm. Fifty seeds of Japanese radish seeds were uniformly seeded on the cultivation bed A on the composition, the surroundings of the plastic container were shielded from light by a cardboard box, and left at room temperature. On the third and sixth days after sowing, 10 radish radishes that germinated and grew were extracted, and their plant height was measured to determine the degree of growth. Similarly, the diameter 9
3.0 cm on the bottom of a 15 cm high plastic container
The cultivation bed B on which absorbent cotton having a thickness of mm or 10.0 mm was placed was cultivated under the same conditions, and the growth rate was measured. Table 2 shows the results.

[0070]

[Table 2]

From the results shown in Table 2, it can be seen that the Japanese radish cultivated on the composition of the present invention (cultivation bed A) grew better than that cultivated on absorbent cotton (cultivation bed B).

In order to obtain good growth of the Japanese radish, the absorbent cotton required a thickness of 10.0 mm.
The composition of the present invention sufficiently supported and grown the Japanese radish at a thickness of 3.0 mm.

In the cultivation system using absorbent cotton, the main root of the Japanese radish was localized in the surface layer without penetrating deep into the absorbent cotton, and the amount of lateral roots (root hair) was small, and the root was easily pulled out.

In the cultivation system using the composition of the present invention, a large number of lateral roots are generated at the same time as the main roots are spread radially in the surface layer of the composition, and the root cap (growth point) of the lateral roots is included in the composition. Had penetrated and was strongly adhered to the composition. Furthermore, these stretched roots were intertwined with the roots of distant individuals as well as the roots of adjacent individuals and integrated.

Regarding moisture control, the composition of the present invention was kept in a sufficiently wet state without replenishing water for 6 days, whereas absorbent cotton was used every other day to prevent the surface from drying. An appropriate amount of water had to be replenished.

Example 3 BPR2001 strain (FERM)
Bacterial cellulose produced by aeration and agitation culture of BP4545) was suspended in water to prepare a 3.0% (% by weight) suspension, thereby preparing an artificial soil composition of the present invention. Diameter 9
cm, 10cm on the bottom of a 15cm high plastic container
Were pierced at five places, and a nonwoven fabric made of PP having a basis weight of 80 was laid. Here, the above-mentioned artificial soil composition was cast, and the thickness was 40 mm.
A mm cultivation bed A was prepared. Similarly, as a control,
The cultivation bed B was prepared by placing vermiculite so as to have a thickness of 40 mm.

[0077] Beconia Listida (List)
The stem of ida) was cut into 50 cm lengths and used as cuttings. Three cuttings were inserted per cultivation bed, and after sufficient watering, they were placed in a half-shade room to supply water to such an extent as to prevent the cultivation bed from drying. Rooting status was observed for 1-3 weeks. Table 3 shows the results.

[0078]

[Table 3]

In the table,-means no rooting, + means rooting (the number of + indicates the degree of development). In the system using the composition of the present invention, rooting was observed on the 10th day, and thereafter, it was well developed. Rooting was observed about 2 weeks after the start of cultivation in the control line, and the development thereafter was also poor.

These are the results of an experiment conducted in an unconditioned room in early May.

[0081]

According to the present invention, stable support of seeds and plants is possible even under difficult conditions. A small amount of the composition can sufficiently retain water and supply it to the plant.

Claims (7)

(57) [Claims] 1. An artificial soil composition comprising bacterial cellulose. 2. The composition of claim 1, further comprising water. 3. The composition according to claim 1, further comprising a fertilizer. 4. The composition according to claim 1, further comprising a microorganism belonging to the genus Acetobacter or the like. 5. The composition according to claim 4, further comprising a culture medium. 6. A method for retaining seeds using the composition according to claim 1. 7. A method for supporting a plant or a fragment thereof by the composition according to any one of claims 1 to 5.