JPH06209662A - Artificial soil for sterile plant - Google Patents

Abstract

PURPOSE:To obtain the subject soil, used for germinating, rooting, acclimatizing and raising seedlings of a seed or a redifferentiated tissue under a sterile environment and capable of preventing the root from being deficient in oxygen and nutriments and water from outflowing without damaging the root by aggregating the soil into a granular or a stringy form with a gelatinous supporting material. CONSTITUTION:This artificial soil is obtained by dissolving powder of sodium alginate in water so as to provide 3% concentration, then dropping the resultant solution into a CaCl2 solution prepared at 0.1 M concentration with a syringe, allowing the prepared mixture to stand for 30min, gelatinizing the mixture, forming a granular molded body composed of a gelatinous support having 20-50% voids, subsequently introducing the resultant molded body into a liquid culture medium without containing a phytohormone, permeating the liquid culture medium thereinto, then placing the granular molded body in a culture device and sterilizing the molded body in an autoclave. The artificial soil is used for germinating, rooting, acclimatizing or raising seedlings of a plant seed or a redifferentiated tissue under a sterile environment and capable of preventing the root from being deficient in oxygen and nutriments and water from outflowing to the outside and taking out the plant without damaging the root at all.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aseptic plant artificial soil.

[0002]

2. Description of the Related Art Virus-free plants, meliclonic plants and germinated germinated plants obtained by culturing plant growth points, foliage or seeds under aseptic conditions are agar or gellan gum immediately before soil cultivation. Rooted on a solid medium using a gel support material of, and transplanted to the field, these germ-free plants have roots that are densely expanded in the medium, so the roots are removed when the seedlings are taken out of the container. There was a drawback that the rooting rate in soil decreased because it was damaged or the roots were cut and remained in the medium.

Further, some plants can take out the roots intact, but the medium adheres to the roots, so that when they are transplanted to soil, they have a drawback that they cause the growth of fungi and cause root rot.

Therefore, when transplanting a conventional sterile plant to a field, the seedlings are carefully removed from the container or the container is broken to separate the seedlings from the medium so that the roots are not damaged.
Furthermore, the roots are thoroughly washed with running water to remove the adhered agar, and then transplanted to a sterile artificial soil such as perlite and vermiculite that has been sterilized in advance, and the conditions of light, temperature and humidity are taken for 1 to 4 weeks to produce an artificial environment. Therefore, it took time and effort to put the acclimation process into the natural environment.

However, even if such tedious acclimation is carried out, the roots of the seedlings grown in the gel-like solid medium grow in a water-immersed state, degrading the spontaneous absorption ability of water and nutrients. In addition, since it does not have a certain gas phase as in soil, it is slow to grow and weak to dryness. Many of the easy field transplants can be colonized in natural soil by roots emerging during acclimation, but such plant species are very limited.

Therefore, as a method for carrying out the steps of rooting, acclimation, and raising seedlings with the same support material, and transplanting the cultured seedlings into the field without damaging the roots, a method for acclimatizing and raising seedlings of cultured plants using ceramic fibers as the support material. Was proposed (Japanese Patent Laid-Open No. 3-133)
325). In the acclimation seedling raising method, the growth of fine roots was vigorous from the culturing step, and the rooting was excellent and the acclimation efficiency was higher than the conventional methods.

However, since ceramic fibers are aggregates of inorganic fibers, they tend to elongate in the fiber direction, but growth tends to be hindered because the fibers are strong in the vertical direction. The roots tend to be elongated and elongated, and root tissues such as tuberous roots are difficult to grow.

[0008] Further, since ceramic fibers are inorganic fine fibers, they are basically of the same quality as soil, but in plant seedlings whose roots are edible, the fine fibers are roots. The fibers may be stuck and remain, so it is necessary to completely remove the fibers. However, it is very troublesome to remove the fibers that are entangled in the fine roots and the root tips, and there is a problem that the range of usable plants is limited.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide an artificial soil for aseptic plants which solves the above-mentioned problems.

[0010]

Means for Solving the Problems The present invention is a sterile plant artificial soil used in the process of germination, rooting, acclimation or seedling of plant seeds or regenerated tissues under a sterile environment, which is gel-like. An aseptic plant-made artificial soil, characterized in that it is formed into a granular or string-like shaped body by a support material and the shaped bodies are assembled.

The present invention will be described in detail below. The molded product of the present invention has a granular or string-like shape, and the particle size of the granular molded product and the diameter of the string-shaped molded product are not particularly limited, but when they are assembled, the porosity is in the range of 20 to 50%. It is preferable that the size is Porosity is 2
When it is less than 0%, the air permeability is lowered, which is not preferable, and when the porosity exceeds 50%, it is not preferable because it is too dry or it is difficult to absorb nutrients. More preferably, it is 25 to 40% from the viewpoint of the growth of the sterile plant and the ease of separating the root of the sterile plant and the artificial soil.

As the gelling support material for forming the artificial soil in the present invention, all gelling medium support materials generally used for culturing plants or microorganisms can be used. Among them, it is preferable to use alginate, gellan gum, agarose, agar, and gelatin from the viewpoint of moisturizing property and physical stability and mechanical strength after molding, and particularly from the viewpoint of moldability and root growth, alginate. , Gellan gum, and agar are preferably used.

In the method for forming artificial soil in the present invention, the steps are slightly different depending on whether an alginate or a polysaccharide having a carboxyl group such as gellan gum is used as a gelling support material, or not. Each method will be described below.

First, the case where a polysaccharide having a carboxyl group is used as the gel support material will be described. Polysaccharides having a carboxyl group are generally Ca, A
It is known to form a strong gel by forming a salt with a divalent metal cation such as l, Ba or Cu.
Here, the production method using alginate will be described in detail, but gellan gum is also produced in the same process.

First, sodium alginate powder was added.
Dissolve in water to a concentration of 0.5-10%, then 0.
Injecting the previously prepared sodium alginate solution into a salt solution of a divalent metal cation such as CaCl ₂ solution adjusted to a concentration of 05 to 0.5 M, and leaving it for 10 minutes to 1 hour,
A gel is formed when sodium replaces calcium.
At this time, when it is desired to form a granular form, a sodium alginate solution is dropped and injected from above the CaCl ₂ solution to cause gelation with the size of the droplet. In addition, if you want to form a string, add sodium alginate solution to CaCl ₂
When directly injected into the solution, a string-like gel having a diameter corresponding to the thickness of the injection port is formed.

When it is desired to prepare the artificial soil having a high porosity, a large gel can be prepared. At this time, when a large gel is to be prepared with a granular gel, a high-concentration sodium alginate solution is prepared. , By forming large droplets by increasing the solution viscosity. On the other hand, when it is desired to make a large-sized string-like gel, the size of the injection port for injecting the sodium alginate solution into the CaCl ₂ solution is increased.

Next, the constant volume of the granular and / or string-like gel molded by such a method is adjusted so that the concentration of each component is twice as much as that of the usual use, and the same volume of the plant liquid as the gel is used. It is put into the medium and stirred to allow the medium components to penetrate into the gel for completion.

Furthermore, when the artificial soil is used in a sterile environment, a series of manufacturing steps may be carried out in a sterile facility such as a clean bench after sterilizing the above materials.
It is easier to sterilize the sterile soil in a general room and then sterilize it using a sterilizer such as an autoclave.

Next, the case where a gel supporting material other than a polysaccharide having a carboxyl group is used as the gel supporting material will be described. It is known that agarose, agar, gelatin, etc., simple polysaccharides having no substituents such as carboxyl groups, and / or proteinaceous gel-like support materials are gelated by heating once and then cooling. There is. Here, the production method using agar will be described in detail, but the same steps are also performed when agarose or gelatin is used.

The method for producing the artificial soil using agar is as follows:
Agar is added to a liquid medium for plants prepared to have twice the concentration of each component to a concentration of 0.8 to 10%, heated to dissolve the agar once, and cooled to 10 ° C or less in advance. It is completed by pouring it into cold water. At this time, the method of forming into a granular shape or a string shape conforms to the method using alginate. In addition, the method of adjusting the porosity is adjusted based on the same principle as in the case of alginate.

Furthermore, when the artificial soil is used in a sterile environment, after sterilizing the above-mentioned materials, a series of manufacturing steps are carried out in a sterile facility such as a clean bench.
A method in which the sterile soil is prepared in a general room and then sterilized by using a sterilizer such as an autoclave like alginate cannot be used because the gel is dissolved by reheating.

[0022]

The artificial soil of the present invention has an appropriate gas phase due to its higher porosity than that of a normal solid medium, prevents oxygen deficiency of roots, and promotes healthy growth. Further, since the nutrients and water are retained in the formed granular body and / or string-like body and do not unnecessarily flow out to the outside, the roots are not soaked in water and the spontaneous absorption ability is improved. Furthermore, when transplanting seedlings in a natural environment, they can be taken out without damaging the roots, and the porosity can be set freely by adjusting the size and shape, so it is appropriate depending on the plant species and the stage of growth. Can be raised under various conditions. It is considered that, due to the above-mentioned actions, a high seedling survival rate can be obtained in a wide variety of plant species.

[0023]

【Example】

Example 1 Sodium alginate powder was dissolved in water to a concentration of 3%. 500m of this sodium alginate solution
1 was adjusted to a concentration of 0.1 M and dropped into the CaCl ₂ solution from above using a 50 ml syringe.
It was allowed to stand for a minute to form a granular gel. Next, 500 ml of MS (Murashige and Scoob) liquid medium containing no plant hormone was prepared, and the above-prepared granular gel was put into this liquid to be permeated.

The granular artificial soil prepared by the above method was placed in a culture vessel and sterilized by an autoclave. The porosity of the granular artificial soil prepared at this time was about 34%. After transplanting 5 symbidiums obtained by preculturing for 4 weeks into this artificial soil, 23 ° C, 5,000 lux, 14
After culturing under time illumination for 6 weeks, the moss was directly transplanted to a pot containing moss without acclimation, and cultivation was continued in a greenhouse. Four weeks later,
When the condition of the seedlings was observed, all 5 seedlings were alive and grew normally.

Example 2 Sodium alginate powder was dissolved in water to a concentration of 5%, and 500 ml of sodium alginate solution was added.
50m in CaCl ₂ solution adjusted to a concentration of 0.1M
Direct injection was performed using a 1-syringe and left for 30 minutes to form a string-like gel. The MS medium was then infiltrated by the same method as in Example 1 to prepare a string-shaped artificial soil. The porosity of the string-like artificial soil created at this time was about 49%. Five Cymbidium obtained by preculturing for 4 weeks were transplanted to this artificial soil, and the culture was continued under the same conditions as in Example 1 for the same period, and directly transplanted into a pot containing water moss without acclimation. The cultivation was continued in the greenhouse. After 4 weeks, the condition of the seedlings was observed, and it was found that all 5 plants were alive and grew normally.

[0026]

Industrial Applicability The artificial soil of the present invention has a proper gas phase because it uses a shaped body of a specific shape, and prevents root oxygen deficiency and promotes normal growth. Further, since the nutrients and water are retained in the molded body and do not unnecessarily flow out to the outside, the roots are not soaked in water and the spontaneous absorption ability is improved. Furthermore, even when transplanting seedlings in a natural environment, the roots can be taken out without damaging the roots at all, and the porosity can be set freely by adjusting the size and shape when molding, so plant species and the stage of growth Can be grown under appropriate conditions. Furthermore, if the nutrient concentration of the medium is made low, it is possible to use the bacteria without propagating even in a natural environment, and it is possible to further promote the growth of seedlings.

Claims (5)

[Claims] 1. A sterile plant artificial soil used in the process of germination, rooting, acclimation or seedling raising of a plant seed or a regenerated tissue under a sterile environment, which is granular or string-shaped by a gel support material. An artificial soil for aseptic plants, which is formed into a compact and is then assembled. 2. The aseptic plant-made artificial soil according to claim 1, which is formed into a granular shape and / or a string shape so that the porosity is 20 to 50%. 3. The aseptic plant-made artificial soil according to claim 1, which is formed into a granular shape and / or a string shape so that the porosity is 25 to 40%. 4. The aseptic plant-made artificial soil according to claim 1, wherein alginate, gellan gum, agarose, agar and gelatin are used as the gel support material. 5. The aseptic plant-made artificial soil according to claim 1, wherein alginate, gellan gum, and agar are used as the gel support material.