JP2001190106A - Coating material for seed, and coated seed - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating material for seeds, especially suitably usable, for example, for fine seeds having <=1 mm average seed diameter, and so-called light-favoring seeds, and capable of suppressing the decrease of germination rate, and further to provide the coated seeds. SOLUTION: This coating material for the seeds comprises a diatomaceous earth containing >=10 wt.% particles maintaining >=50% shapes of diatom cells in unbroken state based on the whole diatomaceous earth, and having <=40 μm average particle diameter, and a binder. The coated seeds are obtained by coating the seeds with the coating material for the seeds.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating material for seeds such as flowers and vegetables, and a coated seed. More specifically, for example, a seed coating material and a coated seed that can be used particularly preferably for microscopic seeds having an average seed diameter of 1 mm or less and so-called photophilic seeds that require light as germination conditions. It is about.

[0002]

2. Description of the Related Art Conventionally, for example, in the case of seeds of flowers, vegetables, etc., the seeds are coated with a coating material in order to facilitate sowing (saving of sowing work). ing. However, the germination rate of coated seeds coated with a coating material may be lower than that of uncoated seeds. Therefore, various coated seeds that do not cause a reduction in germination rate have been proposed.

[0003] As a kind of the coated seed which does not cause the reduction of the germination rate as described above, for example, the seed layer expands with water after sowing and watering, so that the coat layer cracks and collapses, and falls off from the seed. There are a "crack type" and a "collapse type" in which a water-soluble binder in the coating material dissolves in water and the coat layer collapses when the coated seed absorbs water. In each of the two types of coated seeds, the seeds are exposed due to the falling off of the coat layer, so that the germination of the seeds is not inhibited.

[0004] As the above-mentioned "crack type" coated seed, for example, Japanese Patent Application Laid-Open No. 3-94604 discloses a coated seed in which a coating layer is formed by a powder or the like comprising a mixture of attapulgite and calcium stearate. . As the above-mentioned “collapse type” coat seed, for example, Japanese Patent Application Laid-Open No. 8-56426 discloses a coat seed in which a coat layer is formed with pyrophyllite and a water-soluble binder.

[0005]

However, for example,
In the case where the average seed diameter of the seed to be coated is 1 mm or less, if the seed is coated using the above-mentioned conventional “crack type” coating material, the seed has a weak water absorption power. However, even if it swells with water, the coat layer does not crack and does not peel off.

On the other hand, when seeds are coated using the above-mentioned conventional “collapse type” coat material, depending on the water conditions after sowing and irrigation, a water-soluble binder involved in the collapse of the coat layer can coat the seed surface. The seeds are suffocated because they are covered, and the seeds cannot be suffocated or illuminated sufficiently. In the case of a coating material that does not use the above-mentioned binder, the strength (compression strength) of the coating layer against external pressure is insufficient, so that the shape as a coated seed cannot be maintained.

For example, when seeds to be coated are so-called photophilic seeds that require light as a germination condition, such as begonia, exacum, lisianthus, petunia seeds, etc., the seeds may be soil. Without being buried inside,
The seeds need to be placed on the ground and sown so that they are exposed to light. However, even when the conventional “crack type” and “collapse type” coating materials are used for micro-seed having an average seed diameter of 1 mm or less, after sowing and watering, the coat layer does not peel off from the seeds. In the case of such photophilic seeds, there is a problem that the seeds are not sufficiently exposed to light, and the germination rate is significantly reduced.

[0008] The present invention has been made in view of the above-mentioned conventional problems.
The present invention is to provide a seed coating material and a coated seed which can be used particularly preferably for micro seeds having a diameter of not more than mm or so-called photophilic seeds and can suppress a decrease in germination rate.

[0009]

Means for Solving the Problems The present inventors have diligently studied a seed coating material and a coated seed in order to achieve the above object. As a result, by coating the seeds with a coating material containing diatomaceous earth having the shape of the diatom cells in a non-destructive state, that is, particles (cell particles) that relatively maintain the original shape of the cells within a specific range, The inventors have found that the above objects can be achieved, and have completed the present invention.

[0010] That is, in the seed coating material of the first aspect of the present invention, in order to solve the above-mentioned problems, the ratio of particles that maintain the shape of non-destructed diatom cells to 50% or more in the entire diatomaceous earth is determined. 10% by weight or more and an average particle size of 40%
It is characterized by including diatomaceous earth having a size of not more than μm and a binder.

[0011] According to the above configuration, the diatomaceous earth contains 10% or more of particles that maintain the shape of the diatom cells in a non-destructive state at 50% or more.
Since it is contained in a proportion of not less than weight%, the shape of the original cell is maintained to some extent. Therefore, by forming a coat layer together with the binder, it is possible to obtain a coated seed having a sufficient compressive strength and an excellent method of disintegration (disintegration) of the coat layer when irrigated after sowing. Can be.

That is, by using diatomaceous earth in which the original shape of cells is relatively maintained, the water absorption rate of the coat layer and the water retention thereof can be increased. Therefore, when water is irrigated after sowing, the coat layer immediately absorbs water due to the water absorption of the diatomaceous earth itself, and disintegrates and peels off from the seed immediately regardless of the expansion of the seed. As a result, the seeds are exposed and do not inhibit the germination of the seeds. Therefore, according to the above configuration, for example, it is particularly preferably used for minute seeds having insufficient water absorption of the seeds themselves, having an average seed diameter of 1 mm or less, and seeds requiring light as a germination condition. It is possible to provide a coating material that can be used.

[0013] The seed coating material according to the second aspect of the present invention comprises:
In order to solve the above-mentioned problems, the content of diatomaceous earth in a seed coating material is 50% by weight or more.

According to the above configuration, when the content of the diatomaceous earth is within the above range, the coat layer can more reliably absorb water in a range sufficient to cause cracks in the coat layer. For this reason, it is possible to provide a coated seed having more excellent disintegration.

The seed coating material according to the third aspect of the present invention comprises:
In order to solve the above-mentioned problem, in addition to the configuration of claim 1 or 2, the content of the binder in the seed coating material is 15% by weight or less.

According to the above configuration, when the content of the binder is within the above range, it is possible to more reliably generate cracks in the coat layer while maintaining sufficient compressive strength.
Therefore, it is possible to provide a coating material having more excellent compressive strength and disintegration property.

The seed coating material according to the fourth aspect of the present invention comprises:
In order to solve the above problems, the binder is characterized in that it is starch.

According to the above construction, since the binder is starch, the seed surface is covered with a coating material dissolved in water, as seen in the conventional "collapse type" coat layer, and Is not suffocated. That is, by using starch, it is possible to dissolve a part of starch in water to such an extent as to cause cracks in the coat layer by water absorption of the diatomaceous earth itself, irrespective of swelling of the seed itself coated. Therefore, unlike the conventional “crack type” coat layer, the coat layer does not collapse depending on the swelling of the seed being coated, etc. Can be demonstrated. For this reason, it is possible to provide a coating material that can be more suitably used for minute seeds having an average seed diameter of 1 mm or less and seeds requiring light as germination conditions.

According to a fifth aspect of the present invention, there is provided a coated seed coated with the seed coating material according to any one of the first to fourth aspects, in order to solve the above problems. .

According to the above arrangement, the seeds are coated with the coating material to germinate, for example, minute seeds having an average seed diameter of 1 mm or less or seeds requiring light as germination conditions. Without disturbing, and
It is possible to provide a coated seed that is easy to sow.

According to a sixth aspect of the present invention, there is provided a coated seed comprising an inner layer containing a water-absorbing and swelling polymer compound and a seed according to any one of the first to fourth aspects. An outer layer made of a coating material is formed.

According to the above configuration, the water-absorbing and swelling polymer compound promotes water absorption of the coated seeds and also improves the water retention, so that the water absorption rate and the water retaining power of the coated seeds can be increased. For this reason, since the coat layer absorbs water more sufficiently, cracks are easily generated, so that a coat layer having more excellent disintegration properties can be obtained. Also,
Thereby, a decrease in the germination rate can be further suppressed.

According to a seventh aspect of the present invention, there is provided the coated seed according to the fifth or sixth aspect, wherein the average seed diameter of the seed to be coated is 1 mm or less. Features.

According to the above construction, even when the average seed diameter of the seed to be coated is relatively small and it is difficult to sufficiently swell the seed by water absorption, the seed is excellent in disintegration and the germination rate Can provide a coated seed which can suppress the decrease of the amount.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION In the seed coating material of the present invention (hereinafter simply referred to as “coating material”), the ratio of particles which maintain the shape of non-destructed diatom cells to 50% or more in the whole diatomaceous earth is determined. 10% by weight or more and the average particle size is 40μ
m and a binder.

With respect to the diatom cell according to the present invention, the “non-destructive state” refers to a state in which the original shape of the diatom cell, that is, the original shape of the cell is completely maintained and is not damaged at all. The percentage (%) of the shape of the diatom cells in the non-destructive state is determined by, for example, an electron microscope.
It can be confirmed by measuring the cell diameter, volume, cross-sectional area and the like.

As the diatomaceous earth, diatom cells having a predetermined shape collected from the ore deposit are used as they are, or are subjected to processing such as drying, calcination, pulverization, classification, purification, fusion or the like according to a standard method. Thereby, it is processed to have a particle size within a predetermined range. The diatomaceous earth according to the present invention has a diatom cell shape of 5 in a non-destructive state.
Particles kept at 0% or more contain at least 10% by weight of the whole diatomaceous earth.

The present inventors have paid attention to the advantage of selecting diatomaceous earth contained in the coating material at the raw material stage. As the raw material, diatom cells in which the shape of non-destructive diatom cells is maintained at a certain ratio or more are used. It has been found that coated seeds obtained by coating seeds with a coating material containing diatomaceous earth whose shape is relatively retained are excellent in disintegration upon water absorption and can suppress a decrease in germination rate.

The ratio of particles maintaining the shape of diatom cells in a non-destructive state of 50% or more to the entire diatomaceous earth is 10% by weight.
The amount is not particularly limited as long as it is above, but it is more preferably 20% by weight or more, and most preferably 50% by weight or more.

The diatomaceous earth according to the present invention has an average particle size of 40
It is not particularly limited as long as it is not more than μm, but it is more preferably in the range of not more than 30 μm,
It is particularly preferable that the ratio is within the range. Average particle size is 40μ
If it exceeds m, processability is poor. For example, if the average seed diameter of seeds to be coated is 1 mm or less, a uniform and sufficient compressive strength coat layer may not be formed.

The average particle size of the diatomaceous earth can be measured by, for example, a laser method or an electric conductivity method (a Coulter counter).

The ratio of the diatomaceous earth to the total amount of the seed coating material (the content of diatomaceous earth in the seed coating material) depends on the combination of the diatomaceous earth used and the binder, or the type and average seed diameter of the seed to be coated. However, it is more preferably at least 50% by weight, further preferably at least 70% by weight, particularly preferably at least 90% by weight. If the ratio of the diatomaceous earth is out of the above range, there is a possibility that a coat layer having a uniform and sufficient compressive strength cannot be formed, or the disintegration after sowing and watering is not sufficient, and the germination rate may be reduced.

As the binder contained in the coating material, specifically, for example, polyvinyl alcohol (PVA),
Polyvinylpyrrolidone (PVP), carboxymethylcellulose (CMC) and its salts, starch, sucrose, cellulose acetate, cellulose acetate propionate, methylcellulose, hydroxypropylcellulose, pullulan, gelatin, etc., but have an adverse effect on seeds The substance is not particularly limited as long as it is a substance that does not exert any effect. Only one kind of these binders may be used, or two or more kinds may be used in combination. Among the binders exemplified above, starch is particularly preferred, and starch having a solubility in water of 50% or less is most preferred.

Specific examples of the starch include corn starch and the like. When starch is used as a binder, the binder does not dissolve in water to the extent that it completely covers the seed surface after sowing and watering. Therefore, without suffocating the seeds, since it is possible to more reliably generate cracks in the coat layer, it is possible to form a coat layer with better disintegrability of the coat layer after sowing and watering,
For example, it is possible to provide a seed coating material more preferably used for a seed having an average seed diameter of 1 mm or less. In particular, when a starch having a solubility in water of 50% or less is used, the coat layer can be more reliably cracked without suffocating the seed.

The solubility of the above-mentioned binder in water is not particularly limited, but a binder having a solubility of 10% or more and 30% or less is more preferable.

The ratio of the binder to the total amount of the seed coating material (content in the seed coating material) depends on the combination of the diatomaceous earth used and the binding material, or the type of seed to be coated and the average seed diameter. However, it is more preferably within a range of 15% by weight or less, and 5.0% by weight to 10% by weight.
More preferably, it is within the range of weight%. If the ratio of the binder is out of the above range, a uniform and sufficiently compressive strength coat layer may not be formed, or the stability of the coated seed during seeding or storage may be impaired.

The binder may be contained in the coating material in any state, such as a powder state, an aqueous solution, a suspension or a dispersion. Note that when the binder is used in the form of an aqueous solution, suspension, or dispersion, the concentration of the aqueous solution or the like may be appropriately set according to the type of the binder.

The coating material according to the present invention may contain, if necessary, other powders other than diatomaceous earth, such as pyrophyllite and kaolin, or phytohormones, in addition to the diatomaceous earth and the binder. Additives (auxiliaries) such as plant nutrients, plant growth regulators, pesticides, disinfectants / disinfectants, oxygen generators, heating agents, fertilizers, coloring agents and repellents to prevent birds from eating. May be included. The content of the additive in the coating material may be set according to various performances to be imparted to the coated seed, and is not particularly limited.

The coating material according to the present invention can be obtained by mixing the diatomaceous earth, the binder and, if necessary, other powders and additives. The method for producing the coating material, that is, the method and order for mixing the above components are not particularly limited.

The coated seed of the present invention has an inner layer containing the water-absorbing swellable polymer compound and, if necessary, the above-mentioned coating material, for example, in the vicinity of the seed, that is, for example, for the seed to be coated. May be formed on the surface or the like. Specific examples of the water-swellable polymer compound according to the present invention include low-substituted hydroxypropylcellulose (L-HPC), cross-linked polyacrylic acid (PAA), and the like. The ratio of the water-absorbing swellable polymer compound used in the inner layer to the entire coating material used in the inner layer is not particularly limited,
More preferably, it is within the range of 20% by weight or less.
More preferably, it is in the range of 15% by weight to 15% by weight.

The thickness of the inner layer may be appropriately determined according to the average seed diameter of the seed to be coated, and is not particularly limited. The formation of the inner layer can be performed prior to the formation of the coat layer (outer layer), for example, in accordance with a coating operation (described later) on the seed with a coat material.

By forming the inner layer as described above,
Since the water-absorbing and swelling polymer compound promotes water absorption of the coated seeds and also improves the water retention, the water absorption rate and the water retention of the coated seeds can be increased. For this reason, a coat layer having more excellent disintegration properties can be obtained. This can further suppress a decrease in the germination rate.

Examples of a granulating apparatus that can be suitably used for coating seeds using the coating material having the above-mentioned configuration include, for example, known rotary pan-type granulators and fluidized-bed type granulators. , But is not particularly limited. About an example of a method of manufacturing a coated seed,
The procedure when using a granulating device will be described below.

First, seeds are put into a granulator, and the above-mentioned coating material prepared in advance is gradually added to the granulator while stirring at a predetermined rotation speed. Then, by stirring the seed and the coating material for a predetermined time, a granulation operation (coating operation) is performed.
I do. Incidentally, the coating material, in addition to the method of preparing and adding after, for example, diatomaceous earth, and, if necessary,
A method of adding or spraying and spraying an aqueous solution, suspension or dispersion of the binder while charging other powders may be used. When the binder is added in the form of powder,
It is preferable to spray water appropriately. Thereby, a coat layer (outer layer) is formed, and a coated seed is manufactured. The rate of addition of the coating material is such that the granulation operation can be easily performed.
Can be adjusted as appropriate by checking.

The coated seed thus obtained is preferably subjected to a drying operation at a temperature that does not cause heat damage to the seed. In addition, the specific method of coating the seed is not limited to the above-described method.

The seed to be coated in the present invention is
Although not particularly limited, for example, microscopic seeds having an average seed diameter of 1 mm or less, further about 0.1 mm to 0.5 mm, and photophilic seeds requiring light as germination conditions are particularly suitable. It is. Specific examples of the seed include petunia, exacum, eustoma, begonia, coleus, snapdragon, and tobacco. Among the seeds exemplified above, petunia, exacum, eustoma and begonia are most preferred.

The amount of the coating material used for the seeds depends on the kind and size of the seeds, various physical properties to be provided by the coated seeds, the desired size of the coated seeds, the method of producing the coated seeds and the method of sowing. What is necessary is just to set and it is not specifically limited. Further, the average particle size of the coated seed is preferably about 1 mm to 3 mm, more preferably about 1.4 mm to 2.0 mm from the viewpoint of handleability at the time of sowing, but is not particularly limited. In the case where the coated seed has an inner layer and an outer layer, the outer layer may be formed on the seed having the inner layer with the above-mentioned thickness so as to have the above average particle size.

The mechanical strength of the coated seed may be determined, for example, in view of the stability of the coated seed during sowing or storage.
It is sufficient if the compressive strength is in the range of 0.7 N or more.
The method for measuring the compressive strength will be described in detail in the examples below.

The method of sowing the coated seeds is not particularly limited. In the case of photophilic seeds that require light as a germination condition for seeds, the coated seeds are not buried in the soil, It is desirable that the seeds are sown so as to be exposed to light.

In the seed coating material according to the present invention, diatomaceous earth contains particles maintaining the shape of diatom cells in a non-destructive state of 50% or more at a ratio of 10% by weight or more in the whole diatomite. The diatomaceous earth retains the original cell shape to some extent. Therefore, by forming a coat layer together with the binder, coated seeds having sufficient compressive strength and excellent disintegration properties can be obtained.

That is, by using diatomaceous earth in which the original shape of the cells is relatively maintained, the water absorption rate of the coat layer and the water retention thereof can be increased. Therefore, when water is irrigated after sowing, the coat layer immediately absorbs water due to the water absorption of the diatomaceous earth itself, and disintegrates and peels off from the seed immediately regardless of the expansion of the seed. As a result, the seeds are exposed and do not inhibit the germination of the seeds. Therefore, according to the above configuration, for example, it is particularly preferably used for minute seeds having insufficient water absorption of the seeds themselves, having an average seed diameter of 1 mm or less, and seeds requiring light as a germination condition. It is possible to provide a coating material that can be used.

When a predetermined amount of starch, preferably starch having a solubility in water of 50% or less, is used as the binder, coated seeds having more excellent disintegration can be obtained. When using starch as a binder, as seen in the above-mentioned conventional “collapse type” coat layer,
The seed surface is covered with the coating material dissolved in water, and the seeds are not suffocated. In other words, by using starch, regardless of the swelling of the coated seeds,
Due to the water absorption of the diatomaceous earth itself, a part of the starch can be dissolved in water to such an extent that the coat layer is cracked. Therefore, unlike the conventional “crack type” coat layer, the coat layer does not collapse depending on the swelling of the seed being coated, etc. Can be demonstrated. In particular, when the starch has a water solubility of 50% or less, more excellent disintegration can be exhibited. For this reason, the average seed diameter is 1 m
It is possible to provide a coating material that can be more suitably used for minute seeds of m or less and seeds that require light as a germination condition.

The coated seed according to the present invention is coated with the above-mentioned coating material. Thereby, for example, a minute seed having an average seed diameter of 1 mm or less,
It is possible to provide a coated seed that does not inhibit germination of seeds that require light as germination conditions and that is easy to sow.

[0054]

Example: Ease of granulation of coated seeds (processability)
The compressive strength, disintegration, and germination rate were measured by the following methods.

[Workability] The ease of granulation was evaluated in four steps according to the judgment of the operator as follows. When the granulation process is easy, ◎, when the granulation process is possible, ○, when the granulation process is possible, but the coating material does not easily adhere to the seed,
A case where a plurality of seeds were aggregated and granulated was evaluated as Δ, and a case where granulation was impossible was evaluated as ×.

[Compressive Strength] The compressive strength of the coated seeds was measured using a Kiya type compression strength meter (manufactured by Kiya Seisakusho) under predetermined conditions. That is, the coated seeds were compressed under predetermined conditions, and the load applied to the coated seeds at the time when the coated seeds were crushed was defined as the compressive strength (unit: N).

[Disintegration] The coated seeds were allowed to stand on a filter paper soaked in water for a certain period of time, and the size of cracks formed after water absorption was visually observed and compared, and evaluated in the following four grades. That is, ◎ when a relatively large crack has occurred, ○ when the crack has occurred, を when the size of the crack is relatively small, and when there is a tendency to cause a crack, but when the crack does not occur. Was evaluated as “Poor”, and when no change was observed in the coat layer after water absorption, or when the coat layer collapsed by water absorption without generating cracks, it was evaluated as ×. In addition, when not measuring, it displayed with "-".

[Germination rate] The germination rate of the coated seeds was measured by conducting a germination test. First, the cell is 51
Two cell trays were filled with peat moss and vermiculite in predetermined amounts at a weight ratio of 1: 1 and then crushed to obtain soil. Coat seeds were sown on this cultivated soil at a rate of 1 grain / cell. Next, bottom surface water absorption was performed until the maximum water capacity was reached. Thereafter, while appropriately irrigating the above cell tray, "the cell tray is allowed to stand at 20 ° C. and 3000 lux for 12 hours, and then left at 15 ° C. and no light for 12 hours".
Was repeated for 30 days. And
The germination rate (%) was measured 30 days after sowing.

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1 As diatomaceous earth, 95% by weight of diatomaceous earth A containing 60% by weight of particles maintaining the shape of diatom cells in a non-destructive state of 50% or more, and 5% by weight of corn starch as a binder were used. By mixing, the coating material according to the present invention was prepared. The average particle size of the diatomaceous earth A was 12.7 μm.

Next, eustoma was selected as seeds to be coated, and coated seeds were produced using the above coating material. That is, a predetermined amount of seed was put into a 50 cm-diameter inclined rotary pan type granulator, and the coating material was gradually added to the granulator while stirring at a rotation speed of about 30 rpm. Then, a granulation operation was performed by appropriately stirring the seed and the coating material for a predetermined time while spraying water. Thereafter, a drying operation was performed under predetermined conditions to obtain a coated seed according to the present invention. Seed diameter of uncoated seed (hereinafter referred to as original seed) was about 0.3 mm, and coated seed diameter was about 1.6 mm.

The processability, compressive strength,
Disintegration and germination rate were measured by the above methods. In addition, the germination rate of the original seed was measured in the same manner to confirm whether the germination of the seed was inhibited by the coating material. Tables 1 and 2 show the measurement results and the like.

Example 2 A coating material according to the present invention was prepared in the same manner as in Example 1 except that diatomaceous earth A and corn starch were changed to 90% by weight and 10% by weight, respectively. A coated seed according to the present invention was obtained. Workability, compressive strength, disintegration,
And the germination rate was measured by the above method. Table 1 shows the measurement results and the like.

Example 3 The same operation as in Example 1 was carried out except that diatomaceous earth A and corn starch in Example 1 were changed to 85% by weight and 15% by weight, respectively. A coated seed according to the present invention was obtained. Workability, compressive strength, disintegration,
And the germination rate was measured by the above method. Table 1 shows the measurement results and the like.

Example 4 The same operation as in Example 1 was carried out except that diatomaceous earth A was 80% by weight, corn starch was 10% by weight, and pyrophyllite was added as a powder in an amount of 10% by weight. Then, the coated material according to the present invention was prepared, and the coated seed according to the present invention was obtained. The processability, compressive strength, disintegration, and germination rate of the obtained coated seed were measured by the above methods. Table 1 shows the measurement results and the like.

Example 5 The same operation as in Example 1 was carried out except that diatomaceous earth A, corn starch were 10% by weight, and pyrophyllite 20% by weight in Example 1 were added. And a coated seed according to the present invention was obtained. The processability, compressive strength, disintegration, and germination rate of the obtained coated seeds,
It was measured by the above method. Table 1 shows the measurement results and the like.

Example 6 The same operation as in Example 1 was carried out except that diatomaceous earth A and corn starch in Example 1 were changed to 80% by weight, corn starch was added to 10% by weight, and kaolin was added as a powder in an amount of 10% by weight. The coated material according to the present invention was prepared and the coated seed according to the present invention was obtained. The processability, compressive strength, disintegration, and germination rate of the obtained coated seed were measured by the above methods. Table 1 shows the measurement results and the like.

Example 7 The same operation as in Example 1 was carried out except that diatomaceous earth A, corn starch were 10% by weight, and kaolin 20% by weight in Example 1 were added, and the present invention was carried out. A coated material was prepared, and a coated seed according to the present invention was obtained. The processability, compressive strength, disintegration, and germination rate of the obtained coated seed were measured by the above methods. Table 1 shows the measurement results and the like.

Example 8 First, diatomaceous earth A 90% by weight
And 90% by weight of a mixture consisting of 10% by weight of corn starch and L-H as a water-absorbing and swellable polymer compound
PC was mixed at a ratio of 10% by weight to prepare an inner layer coating material according to the present invention. Next, diatomaceous earth A90
The outer layer coating material according to the present invention was prepared by mixing 10% by weight of corn starch with 10% by weight of corn starch.
The average particle size of the diatomaceous earth A was 12.7 μm.

After coating the inner layer coating material on the seed surface, coated seeds were produced using the outer layer coating material. That is, a predetermined amount of seeds (Eustoma) is put into an inclined rotary pan type granulator having a diameter of 50 cm, and the number of rotation is about 30.
While stirring at rpm, the above-mentioned inner layer coating material was gradually added. Then, while appropriately spraying water, the seeds and the inner layer coating material were stirred for a predetermined time to perform a granulation operation. Next, the outer layer coating material was gradually added to the granulator. Then, a granulation operation was performed by appropriately stirring the seed and the coating material whose surfaces were coated with the inner layer coating material for a predetermined time while spraying water. Thereafter, a drying operation was performed under predetermined conditions to obtain a coated seed according to the present invention. The seed diameter in a state where the inner layer was covered was 0.8 mm, and the coated seed diameter was about 1.6 mm.

The processability, compressive strength,
Disintegration and germination rate were measured by the above methods. Table 1 shows the measurement results and the like.

Example 9 First, diatomaceous earth A 90% by weight
And 90% by weight of a mixture of 10% by weight of corn starch and PAA as a water-swellable polymer compound
Was mixed so as to be 10% by weight to prepare an inner layer coating material according to the present invention. Next, the outer layer coating material according to the present invention was prepared by mixing 90% by weight of diatomaceous earth A and 10% by weight of corn starch. The average particle size of the diatomaceous earth A was 12.7 μm. Example 8 was carried out using the above-mentioned inner layer coating material and outer layer coating material.
The same operation as described above was performed to obtain a coated seed according to the present invention.

The processability, compressive strength, and
Disintegration and germination rate were measured by the above methods. Table 1 shows the measurement results and the like.

Example 10 Diatomaceous earth A in Example 1
To 99% by weight, and the same operation as in Example 1 was carried out, except that 1% by weight of PVA was used instead of corn starch as a binder, to prepare a coating material according to the present invention and a coating material according to the present invention. The seed was obtained. The processability, compressive strength, and germination rate of the obtained coated seed were measured by the above methods. Table 1 shows the measurement results and the like.

Example 11 Diatomaceous earth A in Example 1
99.9% by weight, and the same operation as in Example 1 was carried out except that 0.1% by weight of PVA was used instead of corn starch as a binder, to prepare a coating material according to the present invention and A coated seed according to the invention was obtained. The processability, compressive strength, and germination rate of the obtained coated seed,
It was measured by the above method. Table 1 shows the measurement results and the like.

[Example 12] Diatomaceous earth A in Example 1
Is 99% by weight, and CMC-Na (carboxymethylcellulose-
The same operation as in Example 1 was carried out except that 1% by weight of sodium) was used, to prepare a coating material according to the present invention and obtain a coated seed according to the present invention. The processability, compressive strength, and germination rate of the obtained coated seed were measured by the above methods. Table 1 shows the measurement results and the like.

[Example 13] Diatomaceous earth A in Example 1
To 99.9% by weight, and the same operation as in Example 1 was carried out except that 0.1% by weight of CMC-Na was used instead of corn starch as a binder, to prepare a coating material according to the present invention. Thus, a coated seed according to the present invention was obtained. The processability, compressive strength, and germination rate of the obtained coated seed were measured by the above methods. Table 1 shows measurement results
Shown in

[Example 14] Diatomaceous earth A in Example 1
To 99% by weight, and the same operation as in Example 1 was carried out, except that 1% by weight of PVP was used instead of corn starch as a binder, to prepare a coating material according to the present invention and a coating material according to the present invention. The seed was obtained. The processability, compressive strength, and germination rate of the obtained coated seed were measured by the above methods. Table 1 shows the measurement results and the like.

Example 15 Diatomaceous earth A in Example 1
99.9% by weight, and the same operation as in Example 1 was carried out except that 0.1% by weight of PVP was used instead of corn starch as a binder, to prepare a coating material according to the present invention and A coated seed according to the invention was obtained. The processability, compressive strength, and germination rate of the obtained coated seed,
It was measured by the above method. Table 1 shows the measurement results and the like.

[Example 16] Diatomaceous earth A in Example 1
To 80% by weight and corn starch to 20% by weight, the same operation as in Example 1 was performed to prepare the coating material according to the present invention and obtain the coated seed according to the present invention. The processability, compressive strength, and germination rate of the obtained coated seed were measured by the above methods. Table 1 shows the measurement results and the like.

[Example 17] Diatomaceous earth A in Example 1
To 70% by weight and corn starch to 30% by weight, the same operation as in Example 1 was performed to prepare the coating material according to the present invention and obtain the coated seed according to the present invention. The processability, compressive strength, and germination rate of the obtained coated seed were measured by the above methods. Table 1 shows the measurement results and the like.

Example 18 Diatomaceous earth A in Example 1
Was 60% by weight, corn starch was 10% by weight, and 30% by weight of pyrophyllite was added as a powder.
The same operation as in Example 1 was performed to prepare the coating material according to the present invention, and to obtain the coated seed according to the present invention.
The processability, compressive strength, disintegration, and germination rate of the obtained coated seed were measured by the above methods. Table 1 shows the measurement results and the like.

[Example 19] Diatomaceous earth A in Example 1
Example 1 except that 60% by weight of corn starch and 10% by weight of corn starch were added, and 30% by weight of kaolin was added as a powder.
The same operation as described above was performed to prepare the coating material according to the present invention, and to obtain the coated seed according to the present invention. The processability, compressive strength, disintegration, and germination rate of the obtained coated seed were measured by the above methods. Table 1 shows the measurement results and the like.

Example 20 As diatomaceous earth, diatomaceous earth B containing 20% by weight of particles maintaining the shape of diatom cells in a non-destructive state of 50% or more instead of 95% by weight of diatomaceous earth A in Example 1 was used. 10% by weight corn starch
Except for using, the same operation as in Example 1 was performed to prepare the coating material according to the present invention and obtain the coated seed according to the present invention. The average particle size of the diatomaceous earth B is 32.1 μm.
m. Workability, compressive strength,
And the germination rate was measured by the above method. Table 1 shows the measurement results and the like.

Comparative Example 1 Diatomaceous earth A9 in Example 1
The same operation as in Example 1 was carried out except that pyrophyllite was used at 90% by weight and corn starch was used at 10% by weight instead of 5% by weight to prepare a coating material for comparison and a coating material for comparison. The seed was obtained. The processability, compressive strength, disintegration, and germination rate of the obtained comparative coated seed,
It was measured by the above method. Table 2 shows the measurement results and the like.

Comparative Example 2 Diatomaceous Earth A9 in Example 1
Instead of 5% by weight, kaolin was used at 90% by weight and corn starch was changed to 10% by weight, and the same operation as in Example 1 was carried out to prepare a coating material for comparison and a coated seed for comparison. Obtained. The processability, compressive strength, disintegration, and germination rate of the obtained comparative coated seed were measured by the above methods. Table 2 shows the measurement results and the like.

Comparative Example 3 Diatomaceous Earth A9 in Example 1
Instead of 5% by weight, the shape of the non-destructed diatom cells
Diatomaceous earth C containing 60% by weight of particles maintained at 0% or more
The same operation as in Example 1 was carried out except that 90% by weight and corn starch were used at 10% by weight to prepare a coating material for comparison and obtain a coated seed for comparison. The average particle size of the diatomaceous earth C was 74 μm. The processability, compressive strength, disintegration, and germination rate of the obtained comparative coated seed were measured by the above methods. Table 2 shows the measurement results
Shown in

Comparative Example 4 Diatomaceous Earth A9 in Example 1
Instead of 5% by weight, 90% by weight of diatomaceous earth D in which the shape of the diatom cells in the non-destructed state is almost completely destroyed and the shape is not substantially contained is used. %, The same operation as in Example 1 was performed to prepare a coating material for comparison, and to obtain a coated seed for comparison. The average particle size of the diatomaceous earth D was 5 μm. The processability, compressive strength, disintegration, and germination rate of the obtained comparative coated seed were measured by the above methods. Table 2 shows the measurement results and the like.

[0089]

[Table 1]

[0090]

[Table 2]

As is clear from the measurement results in Tables 1 and 2, the coating materials according to the present invention all show a germination rate of 60% or more, and coat the seeds without inhibiting the germination of the seeds. You can see that it can be done. That is, according to the present invention, for example, a seed coating material that can be particularly preferably used for micro seeds having an average seed diameter of 1 mm or less and seeds that require light as a germination condition, and It can be seen that seeds can be provided.

[0092]

As described above, the seed coating material according to the first aspect of the present invention has a shape of diatom cells in a non-destructive state of 50%.
% Of the diatomaceous earth in the diatomaceous earth is 10% by weight or more and the average particle diameter is 40 μm or less, and a binder.

Therefore, the diatomaceous earth contains particles maintaining the shape of the diatom cells in the non-destructive state at 50% or more at a ratio of 10% by weight or more, so that the shape of the original cells is maintained to some extent. For this reason, by forming a coat layer together with the binder, it has sufficient compressive strength, and
After seeding, an effect of obtaining a coated seed excellent in the manner of disintegration (disintegration) of the coat layer when irrigated is obtained.

That is, by using diatomaceous earth in which the original shape of cells is relatively maintained, the water absorption rate of the coat layer and the water retention thereof can be increased. Therefore, when water is irrigated after sowing, the coat layer immediately absorbs water due to the water absorption of the diatomaceous earth itself, and disintegrates and peels off from the seed immediately regardless of the expansion of the seed. As a result, the seeds are exposed and do not inhibit the germination of the seeds. Therefore, according to the above configuration, for example, it is particularly preferably used for minute seeds having insufficient water absorption of the seeds themselves, having an average seed diameter of 1 mm or less, and seeds requiring light as a germination condition. This has the effect of providing a coating material that can be cured.

The seed coating material according to the second aspect of the present invention comprises:
As described above, the content of diatomaceous earth in the seed coating material is 50% by weight or more.

Therefore, when the content of the diatomaceous earth is within the above range, the coat layer can more reliably absorb water in a range sufficient to cause cracks in the coat layer. For this reason, it is effective in providing a coat seed with more excellent disintegration.

The seed coating material according to the third aspect of the present invention comprises:
As described above, in addition to the configuration according to claim 1 or 2,
The content of the binder in the seed coating material is 15% by weight or less.

[0098] Therefore, when the content of the binder is within the above range, cracks can be more reliably generated in the coat layer while maintaining sufficient compressive strength. Therefore, there is an effect that a coating material having more excellent compressive strength and disintegratability can be provided.

The seed coating material according to the fourth aspect of the present invention comprises:
As described above, the binder is configured to be starch.

Therefore, since the binder is starch, the seed surface is covered with the coating material dissolved in water and the seeds are suffocated, as seen in the conventional “collapse type” coat layer. Nothing. That is, by using the starch, it is possible to dissolve a part of the starch in water to such an extent that the coat layer is cracked by the water absorption of the diatomaceous earth itself, regardless of the swelling of the coated seed itself. Therefore, unlike the conventional “crack type” coat layer, the coat layer does not collapse depending on the swelling or the like of the seed being coated. Can be demonstrated. For this reason, fine seeds having an average seed diameter of 1 mm or less,
There is an effect that a coating material that can be more suitably used for seeds that require light as germination conditions can be provided.

The coated seed according to the fifth aspect of the present invention is configured to be coated with the seed coating material according to any one of the first to fourth aspects as described above.

Therefore, when the seeds are coated with the coating material, for example, the average seed diameter is 1 mm.
The following effects can be obtained: coated seeds that do not inhibit germination of the following minute seeds and seeds that require light as germination conditions and that can be easily sown are provided.

[0103] The coated seed of the invention according to claim 6 comprises, as described above, an inner layer containing a water-absorbing swellable polymer compound;
An outer layer made of the seed coating material according to any one of claims 1 to 4 is formed.

Therefore, the water-absorbing and swelling polymer compound promotes the water absorption of the coated seeds and also improves the water retention, so that the water absorption rate and the water retaining power of the coated seeds can be increased. For this reason, since the coat layer absorbs water more sufficiently, cracks are easily generated, so that a coat layer having more excellent disintegration properties can be obtained. In addition, this has an effect that a decrease in the germination rate can be further suppressed.

As described above, the coated seed of the invention according to the seventh aspect has a configuration in which the average seed diameter of the seed to be coated is 1 mm or less, in addition to the configuration according to the fifth or sixth aspect.

Therefore, even when the average seed diameter of the seed to be coated is relatively small and it is difficult to sufficiently swell the seed by water absorption, the seed is excellent in disintegration, and
This has the effect of providing a coated seed capable of suppressing a decrease in the germination rate.

Claims (7)

[Claims] A diatomaceous earth in which the ratio of particles maintaining the shape of diatom cells in a non-destructive state of 50% or more to the entire diatomaceous earth is 10% by weight or more and the average particle diameter is 40 μm or less, A seed coating material comprising: 2. The seed coating material according to claim 1, wherein the content of diatomaceous earth in the seed coating material is 50% by weight or more. 3. The seed coating material according to claim 1, wherein the content of the binder is 15% by weight or less.
Or a seed coating material according to item 2. 4. The seed coating material according to claim 1, wherein the binder is starch. 5. A coated seed, which is coated with the seed coating material according to any one of claims 1 to 4. 6. A coated seed comprising an inner layer containing a water-absorbing swellable polymer compound and an outer layer comprising the seed coating material according to any one of claims 1 to 4. . 7. The coated seed according to claim 5, wherein the average seed diameter of the seed to be coated is 1 mm or less.