JPH0974919A - Hydrogel-raised seedling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain hydrogel-raised seedlings capable of being easily carried out mechanized transplantation to a field and water control and excellent in strength and flexibility by allowing to have a formed culture medium comprising hydrogel as seedling raising culture medium. SOLUTION: This hydrogel-raised seedling is grown from a formed culture medium comprising hydrogel such as sodium alginate, xanthane gum, etc., having a root-growing hole. The root-growing hole preferably penetrates through the formed culture medium comprising the hydrogel and contains fertilizer component and an antiseptic agent in the formed culture medium.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a plant seedling for transplanting into a field.

[0002]

2. Description of the Related Art Many grains, vegetables, or fruit trees are not directly sown in a field but are sown in a seedling cultivation soil for the purpose of improving yield and workability, and are sprouting and transplanted to a field as seedlings. However, at this time, transplanting machines such as rice transplanters are used. These transplanters grip the roots of the seedlings in the nursery box with the planting arms provided on the planting arms and transplant the seedlings in the field.

Usually, in transplanting seedlings, the roots of the seedlings are transplanted in a state where the seedling raising soil is still attached (so-called "soil seedling"). At this time, the tension of the roots in the seedling cultivation soil, the water content of the seedling cultivation soil, or the state of the planting that grips the seedling cultivation soil, the seedling cultivation soil collapses, and the seedlings cannot be gripped or gripped during planting. There was a defect that the seedlings would fall.

A strong grip to prevent such a situation, especially in the case of seedlings of vegetables with a complicated shape, is liable to be damaged, so that a completely automated mechanical transplantation is not possible and a semi-automatic, ie partial Only mechanization was possible. In addition, in the case of these conventional seedlings, it is difficult to control the water content when the amount of the soil is small, so it is usually dealt with by increasing the amount of the soil, but this makes the seedling heavy and the efficiency of machine transplantation. There is a drawback that it becomes worse.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide the above-mentioned problems of the prior art, that is, an aqueous gel-molded seedling which is easy to machine-transplant and manage water.

[0006]

[Means for Solving the Problems] The aqueous gel molding seedling of the present invention has a molding soil made of an aqueous gel as seedling cultivation soil as described in claim 1.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION If the forming medium of the aqueous gel-forming seedling of the present invention has root-growing holes, the wraparound of roots does not occur, so that the moisture in the forming medium surely reaches the target plant. Since it is supplied, initial growth failure and death do not occur, which is desirable. Here, the wraparound of the root will be described with reference to the drawings. The seed 1 sown on the forming medium (symbol δ in the figure) formed by the aqueous gel germinates and its roots usually invade the forming medium and grow by absorbing water or nutrients therein. However, when the main root could not penetrate into the gel, it grows along the outside of the forming medium as shown in FIG. Since seedlings whose main roots have grown in this way cannot use the water (or nutrients) in the molding medium, initial growth failure and death often occur.

If the root-growing holes are aligned with the root-growing direction and penetrate the soil, air (oxygen)
Is supplied from above and below this root growth hole, and even if the main root grows thicker and blocks the upper part of the root growth hole, oxygen is supplied from the bottom, so the root suffocates in the gel, Alternatively, the growth is inhibited, and the situation in which the seeds die after germination and the initial poor growth are reduced, which is desirable. Note that many of these seedlings whose growth of roots is inhibited will be growth-inhibited or die if the weather changes to dryness after transplanting in the field even if no damage occurs during seedling raising.

If the root-growing hole is equal to or thinner than the plant seed for cultivation, and is thicker than the root thickness at the time of germination, the upper part of the hole is not blocked as described above. It is desirable because sufficient oxygen is supplied to the roots. Here, not only oxygen is directly supplied from the main roots that grow the root-growing holes, but oxygen is also supplied to the lateral roots or gel roots that are diffused in the aqueous gel medium from the root-growing holes in the gel medium. It

Examples of the main gel-forming agent used in the forming soil of the aqueous gel-forming seedling of the present invention include sodium alginate, gellan gum, xanthan gum, locust bean gum, carboxymethyl cellulose, pectin, gelatin, carrageenan, and agar. These can be suitably used alone or in combination.

When sodium alginate or pectin is used, a gel is not formed only by dissolving the simple substance in water. Therefore, it is necessary to add a cross-linking agent containing a cross-linking ion such as calcium such as calcium sulfate for forming the gel. There is. Here, sodium polyphosphate such as sodium tripolyphosphate may be added to the system to adjust the function of the crosslinking agent.

When the main component is such that an aqueous gel is formed by such cross-linking, curing (coagulation) due to these cross-linking proceeds rapidly, and warm water or temperature rise is not required for gel formation. Therefore, the energy cost is low and the time until cooling is not required, so it is possible to use part or most of the seeding plant of the normal seedling raising facility as it is, the work is quick, and its efficiency is It is extremely good.

When using a raw material that requires a high temperature in the gel forming step as described above, the high temperature treatment results in an aseptic condition, but the gel then becomes a hotbed of so-called bad bacteria, which harms plants. In many cases, as a result, diseases of crops are likely to occur and the yield is likely to decrease. Therefore, as a gel-forming agent, room temperature or below (40 at maximum)
It is desirable to use the one that is performed at (° C. or lower).

When carboxymethyl cellulose is used as the main gel-forming agent, it is necessary to add a crosslinking agent such as alum. Further, in the molding soil of the aqueous gel molded seedling of the present invention, if a water retention agent is contained, germination is facilitated even in seeds that require a long time before germination, and sufficient water can be supplied to the seeds. As a result, high germination rate and high yield are desirable. A so-called polymer absorbent (water absorbent) is known as a water retention agent.

Here, if the fertilizer component contributing to the growth of the plant is contained in the forming soil of the aqueous gel forming seedling of the present invention, the effect of fertilization can also be obtained, which is desirable. It should be noted that this fertilizer component may be inorganic fertilizer or organic fertilizer as long as it contributes to the growth of the plant, but it may interfere with the gel formation or may cause the gel to coagulate to hinder the growth of the plant. Need to be excluded.

If the molding soil of the aqueous gel-molded seedling of the present invention contains a preservative, gel spoilage can be prevented, and as a result, the growth of bad bacteria that hinders the growth of plants can be prevented. It is desirable because it can have effects such as prevention of plant diseases. In addition, by mixing the disinfectant in the molding soil made of aqueous gel in advance,
It is possible to omit the seed disinfection process. Similarly, it is possible to mix so-called "pesticides" such as insecticides.

If the shape of the shaped soil is cylindrical, prismatic or regular hexahedron, it can be easily handled by the transplanter. It should be noted that these can be sown in a sheet-shaped medium for germination and then cut into seedlings, but in this case, the roots are often scratched during cutting, which often causes damage. It is desirable to seed after forming the forming medium in an independent state. In addition, the size of the molding medium is different in the amount of water depending on the period from germination to transplantation, or the growth rate of the seedlings.
Adjust according to the result, or if there is a shortage,
It is necessary to supply water.

In the above, all of the seedling cultivation soil is shown to consist of an aqueous gel. However, here, the materials usually used as seedling cultivation soil (such as conventional soil and forced soil) are mixed with the aqueous gel raw material. Similarly, the root portion of seedlings sown and germinated on a normal seedling cultivation soil may be coated with an aqueous gel and molded and used. Also,
Ordinary cultivating soil may be placed in a container made of an aqueous gel (in this case, the shape of the container may be appropriately selected), and the seeds may be seeded and germinated to give a seedling. At this time, the step of disinfecting the bed soil or the step of disinfecting the seeds can be omitted by mixing the disinfectant in the aqueous gel. In addition, a pesticide may be mixed if necessary.

[0019]

【Example】

[Aqueous gel medium] The composition and gelling method of the aqueous gel medium used in Examples and Comparative Examples will be described. In addition, room temperature (22 to 25 ° C.) is used unless otherwise specified.
I went in. (A composition) Table 1 shows the compounding amount of each drug of the A composition.

[0020]

[Table 1]

Gellan gum and dextrin were added to water, and they were dissolved by an autoclave treatment at 120 ° C. for 15 minutes, calcium chloride was added, and the mixture was stirred and naturally cooled to room temperature to obtain an aqueous gel.

(B composition) Table 2 shows the compounding amount of each drug of the B composition.
Shown in

[0023]

[Table 2]

Xanthan gum and locust bean gum were added to water and dissolved by an autoclave treatment at 120 ° C. for 15 minutes, and then naturally cooled to room temperature to obtain an aqueous gel.

(C composition) Table 3 shows the compounding amount of each drug of the C composition.
Shown in

[0026]

[Table 3]

Gellan gum, dextrin, xanthan gum and locust bean gum are added to water,
These were dissolved by an autoclave treatment for 15 minutes, and then naturally cooled to room temperature to obtain an aqueous gel.

(D composition) Table 4 shows the amount of each drug of the D composition.
Shown in

[0029]

[Table 4]

After adding agar to water and dissolving it by autoclaving at 120 ° C. for 15 minutes, the mixture was naturally cooled to room temperature to obtain an aqueous gel.

(E composition) Table 5 shows the compounding amount (parts by weight) of each drug of E composition.

[0032]

[Table 5]

The above components were mixed, dissolved by stirring, and allowed to stand to obtain an aqueous gel. In addition, in Table 5, the Mamako inhibitor is an agent that facilitates stirring at the time of preparation by addition to suppress the uneven solidification of the gel (so-called "Mamako"). In this example, stone powder (100 ~ 250
(Mesh) was used (hereinafter the same).

As the water retention agent, a graft starch-based water-absorbing polymer was used as a polymer absorbent, and as a preservative, an organic nitrogen / sulfur-based preservative was used. The MS culture in Fig. 5 is Murashige & Scoog.
This is an abbreviation for Skoog) medium, and this MS is used as a fertilizer component.
Medium was added.

(F composition) Table 6 shows the blending amount of each drug of F composition.
Shown in

[0036]

[Table 6]

Carboxymethyl cellulose and alum were added to water and dissolved by stirring to form an aqueous gel.

(G composition) Table 7 shows the blending amount of each drug of G composition.
Shown in

[0039]

[Table 7]

Pectin, calcium chloride and sodium tripolyphosphate were added to water and dissolved by stirring to form a gel, which was made into an aqueous gel.

(H composition) Table 8 shows the blending amount of each drug of H composition.
Shown in

[0042]

[Table 8]

Gelatin was added to water, dissolved in an autoclave at 120 ° C. for 15 minutes, and then naturally cooled to room temperature to obtain an aqueous gel.

(I composition) Table 9 shows the blending amount of each drug of I composition.
Shown in

[0045]

[Table 9]

Carrageenan and potassium chloride were added to water, dissolved in an autoclave at 120 ° C. for 15 minutes, and then naturally cooled to room temperature to obtain an aqueous gel.

[Examples 1 to 9] A produced as described above
A cylindrical block having a diameter of 3 cm and a height of 4 cm was cut out from the aqueous gel having the composition to the composition K. A hole having a diameter of 0.5 cm and a depth of 0.5 cm is formed in the center of these upper surfaces (FIG. 1A).
reference. Hereinafter, such a shape will be referred to as "a perforated soil block α"), and 100 seeds (Example 1 to Example 9) sown with one tomato seed will be prepared, and these will be heated to 25 ° C. When germinated for 2 weeks and then raised, the respective germination rates were as shown in Table 10.

[0048]

[Table 10]

When the root growth of these plants was observed, all the seedlings grew in the forming soil as shown in FIG. 1 (b), and there was no so-called root wraparound. It was

[Examples 10 to 27] The same perforated soil block α as that used in Examples 1 to 9 was formed from the aqueous gels of the compositions A to K prepared as described above, and the blocks were respectively formed. 100 seeds sown one by one sugar beet seed (Examples 10 to 18), 100 seeds sown one corn seed in a similar manner (Examples 19 to 27)
When they were produced and germinated by keeping them at 25 ° C for 2 weeks and raising seedlings, the germination rate of sugar beet in Examples 10 to 18 was 94 to 97%, and the germination rate of corn in Examples 19 to 27 was 96 to 100. %Met. The root growth of these plants was observed, and none of them had so-called wraparound.

[Examples 28 to 45] Further, the columnar block having the composition A to the composition K has a hole having a diameter of 0.5 cm and a hole penetrating from the center of the upper surface to the lower surface (Fig. 2).
(A), hereinafter referred to as "foraminous soil block β") was prepared, and seeds of sugar beet or corn were sown and germinated in the same manner as in Examples 10 to 27, and seedlings were raised,
A germination rate similar to that of Examples 10 to 18 or Examples 19 to 27 was obtained (Examples 28 to 45). The condition of the germinated seedlings was as shown in Fig. 2 (b), and there was no so-called root wraparound. Although the through holes of this perforated soil block β are slightly smaller than these seeds,
The elasticity of the aqueous gel can be used for seeding as shown in FIG. 2 (a).

[Examples 46 to 63] With respect to the columnar blocks of A composition to K composition, a diameter of 0.3 cm was further added to the hole bottom of the perforated soil block α similar to that used in Examples 1 to 18. The perforated soil block γ (see FIG. 3 (a)) having a stepped portion having a through hole reaching the lower surface of No. 3 was produced, and seeds of sugar beet or corn were sown in the same manner as in Examples 10 to 27 to germinate. As a result, germination rates similar to those of Examples 10 to 18 or Examples 19 to 27 were obtained (Examples 46 to 63). The condition of the germinated seedlings is as shown in Fig. 3 (b), and none of the so-called root wraps occurred.

In the perforated soil block γ having a step, the diameter of the hole above the step indicated by reference numeral γ1 in FIG. 3 (a) is smaller than the seed size of the target plant, and
By making the portion of the hole below the step γ1 smaller than the size of the seed and thicker than the thickness of the main root after germination, it is possible to sow easily without hindering the growth of the target plant. .

In the seedlings of Examples 1 to 63 described above, the seedlings were sown in a seedling-growing soil made of an aqueous gel as described above. In this case, water necessary for germination and growth of seedlings was supplied from the aqueous gel. Therefore, there is no need for watering after seeding,
Therefore, water management is virtually unnecessary.

[Transplantation Test] Next, a transplantation test was conducted.
The seedlings of the above Examples 1 to 63 were subjected to a transplanting test to a field by a vegetable transplanter manufactured by Yanmar, and all of them could be easily mechanically transplanted, and obstacles such as collapse of the seedling cultivation soil part during the transplantation did not occur. It was

[0056]

The strength of the invention is higher than that of ordinary soil, and
Since the water-soluble gel having flexibility is used as the seedling cultivation soil, it can withstand grasping by the transplanter by planting, and as a result, mechanized transplantation to the field is easy and there is no failure. Usually (when using seedlings according to the related art), many plants need to be irrigated immediately after transplantation. However, in the case of the seedlings according to the present invention, irrigation immediately after transplantation is performed due to the large amount of water in the seedling cultivation soil. It is possible to omit it, and even if the weather changes to dry after transplanting, there is little death due to water in the transplanted seedling cultivation soil at the same time.

[Brief description of drawings]

FIG. 1 (a) is a view showing an example of a seeded perforated forming medium. (B) It is a figure which shows the state which (a) germinated and became a seedling.

FIG. 2 (a) is a view showing another example of the seeded perforated forming medium. (B) It is a figure which shows the state which (a) germinated and became a seedling.

FIG. 3 (a-1) is a view showing an example of a perforated forming medium having seeded step portions. (A-2) It is a figure showing the sectional view of (a-1). (B) It is a figure which shows the state which (a) germinated and became a seedling.

FIG. 4 is a view showing a state in which seeds sown in a forming medium have germinated and roots have wraparounded.

[Explanation of symbols]

 1 Seed α Perforated forming medium β Perforated forming medium γ Perforated forming medium γ1 Step δ Forming medium

Claims (7)

[Claims] 1. A water-based gel molding seedling, which comprises a water-based gel molding soil as a nursery soil. 2. The molding soil made of an aqueous gel, which is the seedling raising soil, has root-growing holes.
The aqueous gel-molded seedling described in. 3. The aqueous gel-molded seedling according to claim 2, wherein the root-growing hole penetrates a molded soil made of an aqueous gel. 4. The aqueous gel-molded seedling according to claim 1, wherein the molding soil comprises a gel-forming agent that does not require heating. 5. The aqueous gel molding seedling according to any one of claims 1 to 4, wherein the molding soil has a fertilizer component. 6. The aqueous gel-molded seedling according to any one of claims 1 to 5, wherein the molded soil has an antiseptic agent. 7. An aqueous gel-molded seedling, which comprises a nursery medium for molding grown with an aqueous gel.