JP6794845B2 - Covered seeds, method of producing covered seeds and method of sowing covered seeds - Google Patents

Description

The present invention relates to coated seeds, a method for producing coated seeds, and a method for sowing coated seeds.

With the aging of agricultural workers, it is important to save labor in agricultural work. For example, in paddy rice cultivation, a direct sowing method in which paddy rice seeds are sown directly in a paddy field is becoming widespread for the purpose of saving the trouble of raising seedlings and transplanting. At this time, if various plant seeds including paddy rice seeds are sown directly in the cultivated area, there is an increased possibility that the seeds will be eaten by the birds, causing bird damage. Therefore, in particular, for paddy rice seeds, an attempt has been made to prevent the floating and outflow of seeds and bird damage in paddy fields by coating the paddy rice seeds with iron powder (for example, Patent Document 1 below). See.).

In paddy rice and corn, direct sowing is performed in order to sow in large quantities efficiently. When directly sowing seeds, pesticides such as disinfectants, insect repellents, and herbicides are necessary in the cultivation process from germination of the directly sown seeds to harvesting, and the application of these pesticides is used as seeds. There is a problem that labor and cost are required to perform the seeding separately. In addition, if these pesticides are supported on seeds for direct sowing, there is an advantage that the pesticides can be applied at the same time as sowing, but when the pesticides are used in direct contact with the seeds, the plants are contaminated by the pesticide components and cultivated. Safety is also a concern when considering that plants can be used as food.

Further, in Patent Document 2 below, for the purpose of effectively controlling pests that damage paddy rice, a coating material containing at least iron powder or a molybdenum compound is treated with a chemical containing at least a fungicide or an insecticide. Has been proposed.

Japanese Unexamined Patent Publication No. 2012-70728 JP 2015-139390 Japanese Unexamined Patent Publication No. 2016-136861

If pesticides such as disinfectants, insect repellents, and herbicides can be combined and supported on coated seeds for direct sowing, it is convenient because the labor of spraying pesticides can be saved only by direct sowing of seeds. .. However, iron powder or seeds coated with a coating containing iron powder as a main component have the following problems.

First, when the seeds are coated with iron powder or a coating containing iron powder as the main component, the seeds are coated with a mixture of iron powder and pesticides such as disinfectants, insecticides and herbicides. It is conceivable that the seeds are coated with iron powder, and then the seeds are coated by supporting a pesticide on the surface of the coating. Here, in the coating with iron powder, water is added in the coating treatment process, divalent iron ions are eluted from the iron powder, and further oxidized to ferric iron ions, and then iron hydroxide is formed. At this time, it is considered that the seeds are adversely affected by the heat generated by the oxidation of iron and the high temperature. In addition, mixed pesticides may also be decomposed by the oxidation of metallic iron and high temperature.

In addition, when the seeds are coated with iron powder or a coating containing iron powder as the main component, it takes about 4 days to cure the seeds until iron hydroxide is sufficiently formed and the seeds are covered with iron rust. .. Since iron powder is metallic iron, it is costly and it takes time to complete the iron powder coating, so that the cost and work load are extremely large. Here, iron powder or an iron powder coating made of iron hydroxide does not have the same effect as pesticides such as sterilization and insect eradication, so that the effects such as sterilization and insect eradication are the only pesticides to be supported. It depends on the effect.

Furthermore, since iron hydroxide has a high ability to adsorb organic substances, even if pesticides such as disinfectants, herbicides, and herbicides are carried on the coating, the carried pesticides are adsorbed on the iron hydroxide. It may not be possible to elute efficiently. In addition, iron powder or seed coating containing iron powder as a main component has a dense structure formed by drying iron hydroxide, so that there are no voids and it is difficult for seeds to breathe oxygen. ..

Further, when the seeds of plants such as paddy rice are coated with iron powder as disclosed in Patent Documents 1 and 2, the metallic iron constituting the iron powder generates heat due to oxidation as described above. It is likely to impair seed growth. In addition, since the iron powder disclosed in Patent Document 1 and Patent Document 2 and the molybdenum compound disclosed in Patent Document 2 are relatively expensive coating materials, iron powder and molybdenum compound can be used. If a covering material as a main component is used, the material cost increases.

Furthermore, when seeds coated with iron powder are directly sown and used continuously for a long period of time, the iron powder used for coating and iron hydroxide generated by the oxidation and hydration of metallic iron accumulate on the soil surface. There is concern that problems such as causing iron excess in plants and reducing the utilization efficiency of phosphoric acid due to the binding of phosphoric acid and iron ions may occur. Therefore, there is a demand for the development of coated seeds for direct sowing, which can be used continuously for a long period of time without excessive supply of metallic iron and can carry pesticides.

Here, Patent Document 3 which discloses the seed coating material discloses that slag is used as the seed coating material, and as an example of the slag, steel slag or steelmaking slag is mentioned. However, the only slag that has been specifically verified in Patent Document 3 is the slag (sewage sludge molten slag) obtained by melting and then cooling sewage sludge, etc., and the steel slag or steelmaking slag is specifically. No verification has been done.

Further, in Patent Document 3, a binder is used to coat the slag. According to the verification by the present inventors, even if the seeds are coated with powdered sewage sludge slag, the sewage sludge molten slag alone does not have the property of solidifying, and is disclosed in Patent Document 3 above. When the sludge is used as a seed coating material, it is necessary to use a substance having a solidifying property such as gypsum as a binder. The iron powder disclosed in Patent Document 1 and the like hardens itself by oxidation, so that the binder is not an essential component. However, in Patent Document 3, the binder is essential, so that the material cost Is worried about the rise.

Furthermore, in the sewage sludge molten slag used in Patent Document 3, there is a possibility that harmful heavy metals derived from sewage may be mixed, and there is a concern that harmful heavy metals may be absorbed and accumulated in germinated plants.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to suppress bird damage and to efficiently grow seeds while further reducing the cost. A method for producing coated seeds, a method for producing coated seeds, and a method for sowing coated seeds.

As a result of diligent studies to solve the above problems, the present inventors have found that steel slag and coal ash produced as a by-product in the steel manufacturing process have a relatively low material cost and a fertilizer effect. Focusing on this, we came up with the idea of coating various seeds with such steel slag or coal ash and then treating the seeds with various chemicals, and completed the present invention.
The gist of the present invention completed based on the above findings is as follows.

(1) It is located on the surface of a predetermined seed, and is located on the surface of the coating layer and a coating layer containing at least one selected from the group consisting of steelmaking slag, blast furnace slag, and coal ash. , A chemical layer containing at least one of a disinfectant, an insecticidal agent, or a herbicide, and the coating layer has a pore ratio of 17 to 50% .
( 2 ) The steelmaking slag includes CaO of 25% by mass or more and 50% by mass or less, SiO _{2 of} 8% by mass or more and 30% by mass or less, MgO of 1% by mass or more and 20% by mass or less, and 1% by mass or more and 25. At least one of Al ₂ O ₃ of mass% or less, Mn of 1 mass% or more and 8 mass% or less, and P ₂ O _{5 of} 0.1 mass% or more and 5 mass% or less, the total is 100 mass%. The coated seed according to ( 1 ), which is contained so as to be as follows.
( 3 ) The coated seed according to (1) or (2) , wherein the steelmaking slag is a converter steelmaking slag or an electric furnace steelmaking slag which is at least one of derinsed slag and decarburized slag.
( 4 ) The blast furnace slag includes CaO of 35% by mass or more and 45% by mass or less, SiO _{2 of} 25% by mass or more and 40% by mass or less, MgO of 2% by mass or more and 15% by mass or less, and 8% by mass or more and 20. The coated seed according to any one of (1) to ( 3 ), which contains at least one of Al ₂ O _{3 of} mass% or less so as to have a total of 100 mass% or less.
( 5 ) The coal ash contains CaO of 1% by mass or more and 10% by mass or less, SiO _{2 of} 40% by mass or more and 75% by mass or less, Fe ₂ O _{3 of 2} % by mass or more and 20% by mass or less, and 15% by mass. The coated seed according to any one of (1) to ( 4 ), which contains at least one of Al ₂ O _{3 of} % or more and 35% by mass or less so as to have a total of 100% by mass or less.
( 6 ) The coated seed according to any one of (1) to ( 5 ), wherein the steelmaking slag is a steelmaking slag that passes through a sieve having a pore size of 600 μm.
( 7 ) The coated seed according to any one of (1) to ( 6 ), wherein the blast furnace slag is a blast furnace slag that passes through a sieve having a pore size of 600 μm.
( 8 ) The coated seed according to any one of (1) to ( 7 ), wherein the blast furnace slag is a blast furnace slag that passes through a sieve having a pore size of 75 μm.
( 9 ) The coated seed according to any one of (1) to ( 8 ), wherein the coal ash is a coal ash that passes through a sieve having a pore size of 75 μm.
( 10 ) The content of the coal ash in the coating layer is more than 0% by mass and 20% by mass or less with respect to the total mass of the coating layer, in any one of (1) to ( 9 ). The coated seeds described.
( 11 ) The coating according to any one of (1) to ( 10 ), wherein the content of the drug is 0.01% by mass to 1% by mass with respect to the dry mass of the seed before coating. seed.
( 12 ) The disinfectant is a dithiocarbamate-based disinfectant, isothianyl, flametopyl, etaboxam, 2-[(2,5-dimethylphenoxy) methyl] -α-methoxy-N-methyl-benzeneacetamide, benomyl, oxolinic. The coated seed according to any one of (1) to ( 11 ), which is one or more selected from the group consisting of acid, probenazole, thiazinyl, pyrochyron and diclosimet.
( 13 ) The insect repellent is one or more selected from the group consisting of organophosphorus insect repellents, clothianidin, nitenpyram, benzlutap, thiamethoxam, dinotefuran, pimetrodin, sulfoxaflor, benfracarb, carbosulfan and cartap hydrochloride. The coated seed according to any one of (1) to ( 12 ).
( 14 ) The coated seed according to any one of (1) to ( 13 ), wherein the herbicide is a paraquat-based herbicide.
( 15 ) The coated seed according to any one of (1) to ( 14 ), wherein the coating layer further contains at least one selected from the group consisting of gypsum, iron powder, cement, and molasses. ..
( 16 ) Any of (1) to ( 15 ) having a drug coating layer made of at least one selected from the group consisting of an organism, ceramics, silica, and zeolite on the surface of the drug layer. The coated seed according to one.
( 17 ) The seeds according to any one of (1) to ( 16 ), wherein the seeds are seeds of a plant cultivated in a flooded state or seeds of a plant cultivated in a non-watered state. Coated seeds.
( 18 ) The coated seed according to ( 17 ), wherein the seed of the plant cultivated in the flooded state is a seed of a gramineous plant.
( 19 ) The coated seed according to ( 18 ), wherein the seed of the Gramineae plant is a paddy rice seed.
( 20 ) The coated seed according to ( 17 ), wherein the seed of the plant cultivated in a non-flooded state is a seed of a gramineous plant, a legume family plant, a Polygonaceae plant, an edible herbaceous plant, or a useful plant. ..
( 21 ) The seeds of the rice family plant are land rice seeds, corn seeds, or wheat seeds, the seeds of the legume family plant are soybean seeds or azuki seeds, and the seeds of the tadashi family plant are The buckwheat seeds, the seeds of the edible herbaceous plant are carrot seeds, tomato seeds, or citrus seeds, and the seeds of the useful plants are turf seeds, grass seeds, green fertilizer plant seeds, or flowering tree seeds. , ( 20 ).
( 22 ) At least one of the coating layer, the drug layer, or the drug coating layer located on the surface of the drug layer further contains an alginic acid compound, any one of (1) to ( 21 ). Covered seeds described in.
( 23 ) The coated seed according to any one of (1) to ( 22 ), wherein the seed is a starch-coated seed.
( 24 ) A step of coating a predetermined seed with a mixture obtained by mixing water with at least one selected from the group consisting of steelmaking slag, blast furnace slag, and coal ash, and coating with the mixture. the seeds, sterilization agent, Jomushizai, or, viewed including the steps of treating with an agent containing at least one herbicide, wherein the steel slag, the blast furnace slag, or a particle of the coal ash A method for producing coated seeds , wherein the diameter is adjusted and the pore ratio of the coating layer formed by the mixture is 17 to 50% .
(25) The method for producing coated seeds according to (24), wherein the steelmaking slag is a steelmaking slag that passes through a sieve having a pore size of 180 μm and does not pass through a sieve having a pore size of 22 μm.
(26) The method for producing coated seeds according to (24), wherein the blast furnace slag is a blast furnace slag that passes through a sieve having a pore size of 75 μm.
( 27 ) The coated seed according to any one of (24) to ( 26 ), wherein the ratio of the water in the mixture is 10% by mass or more and 80% by mass or less with respect to the total mass of the mixture. Production method.
( 28 ) The method for producing coated seeds according to any one of (24) to ( 27 ), wherein the mixture further contains at least one selected from the group consisting of gypsum, iron powder, and cement.
( 29 ) The method for producing coated seeds according to any one of (24) to ( 28 ), wherein the water is water containing 10% by mass or more and 50% by mass or less of molasses.
( 30 ) A method for sowing coated seeds, wherein the coated seed according to any one of (1) to ( 23 ) is directly sown in the cultivation area for cultivating the seed.

As described above, according to the present invention, it is possible to suppress bird damage and efficiently grow seeds while further reducing the cost.

Hereinafter, preferred embodiments of the present invention will be described in detail.

(About coated seeds)
First, the coated seeds according to the embodiment of the present invention will be described in detail.
The coated seed according to the present embodiment is located on the surface of a predetermined seed, and contains a coating layer containing at least one selected from the group consisting of steelmaking slag, blast furnace slag, and coal ash, and the surface of the coating layer. It is located in, and includes a drug layer containing at least one of a disinfectant, an insecticide, or a herbicide.

<About seeds>
In the following, first, the seeds used for the coated seeds according to the present embodiment will be briefly described.
As the seeds used for the coated seeds according to the present embodiment, seeds of a plant cultivated in a flooded state or seeds of a plant cultivated in a state of not being flooded can be used. Here, "seed cultivated in a flooded state" means a seed cultivated in a state where the surface of the soil is submerged in water, and "seed cultivated in a state of not being flooded" means. It means seeds that are cultivated in a state where they are flooded and the surface of the soil is not submerged in water.

Of the above two types of seeds, examples of seeds of plants cultivated in a flooded state include seeds of gramineous plants. The seeds of such grasses are not particularly limited as long as they are cultivated in a flooded state, and any known seeds of grasses can be used. Among the seeds of gramineous plants cultivated in such a flooded state, for example, paddy rice seeds can be mentioned.

Of the above two types of seeds, examples of plant seeds cultivated in a non-flooded state include grass seeds, legume seeds, Polygonaceae seeds, and edible plant seeds. In addition, seeds of useful plants and the like can be mentioned.

The seeds of gramineous plants as described above are not particularly limited as long as they are cultivated in a state of not being flooded, and any known seeds of gramineous plants can be used. Typical examples of the seeds of gramineous plants cultivated in such a non-flooded state include upland rice seeds, corn seeds, wheat seeds and the like.

The seeds of the above-mentioned legumes are not particularly limited as long as they are cultivated in a non-flooded state, and any known legume seeds can be used. Among the seeds of legumes cultivated in such a non-flooded state, for example, soybean seeds, adzuki bean seeds and the like can be mentioned.

The seeds of the Polygonaceae plant as described above are not particularly limited as long as they are cultivated in a state of not being flooded, and any known Polygonaceae plant seed can be used. Among the seeds of Polygonaceae plants cultivated in such a non-flooded state, for example, buckwheat seeds and the like can be mentioned.

The seeds of the above-mentioned edible herbaceous plants are not particularly limited as long as they are the seeds of edible herbaceous plants (so-called vegetables) cultivated without being flooded, and known seeds of edible herbaceous plants should be used. Is possible. Typical seeds of edible plants and plants cultivated in such a non-flooded state include carrot seeds, tomato seeds, sugar beet seeds and the like.

The seeds of the useful plants as described above are not particularly limited as long as they are cultivated in a non-flooded state, and known useful plant seeds can be used. Typical examples of useful plant seeds cultivated in such a non-flooded state include turf seeds, grass seeds, green manure plant seeds, flowering tree seeds and the like. Of these, the green manure plant is a plant that is used as a fertilizer for crops to be cultivated later by cultivating the cultivated plant as it is without harvesting it into the soil. Examples of such green manure plants include sorghum and the like.

In addition, bristles may be present on the surface of various seeds as described above. The presence of bristles on the surface of the seed can lead to a phenomenon in which the adhesion between the coating layer and the seed is weakened, as described in detail below. In order to suppress the possibility of such a phenomenon occurring, the surface of the seeds may be covered with starch by immersing various seeds as described above in an aqueous starch solution. This makes it possible to improve the adhesion between the coating layer and the seed, which will be described later. The concentration of the starch aqueous solution in which the various seeds are immersed as described above (that is, the mass ratio of starch to the total mass of the aqueous solution) is not particularly specified, but is, for example, 40% by mass to 80% by mass. Is preferable. By immersing the various seeds as described above in the starch aqueous solution having such a concentration, it is possible to more reliably improve the adhesion between the coating layer and the seeds.

The seeds applicable to the coated seeds according to the present embodiment have been briefly described above.

<About the coating layer>
Subsequently, the coating layer formed on the surface of the seed as described above will be described in detail.
The coating layer according to the present embodiment formed on the surface of seeds as described above contains at least one selected from the group consisting of steelmaking slag, blast furnace slag, and coal ash. Hereinafter, steelmaking slag, blast furnace slag, and coal ash that can be contained in such a coating layer will be described in detail.

In the coating layer of the coated seeds according to the present embodiment, the main component of the coating material is not iron powder but at least one of steelmaking slag, blast furnace slag, or coal ash. As a result, in the coating layer according to the present embodiment, the iron content as a simple substance of Fe is reduced, so that heat generation unlike iron powder coating does not occur. Therefore, in the coating layer according to the present embodiment, the increase in seed temperature due to the heat generation of iron oxidation during the coating treatment can be suppressed more than in the case of iron powder coating, and the high temperature on the seeds causes it. It is possible to greatly suppress damage. Further, the steelmaking slag, the blast furnace slag and the coal ash used as the main components of the coating layer in the present embodiment are cheaper than the iron powder and can be easily consolidated. Therefore, the coating layer according to the present embodiment is superior to the iron powder coating in terms of both cost and workability.

[About steelmaking slag]
Steelmaking slag produced as a by-product in the steelmaking process has been analyzed and controlled in its composition and contains various fertilizer effective elements such as Ca, Si, Mg, Mn, Fe, and P. Therefore, it has been conventionally used as a fertilizer raw material. It is used. In Japan, as fertilizers made from steelmaking slag, there are fertilizers that belong to the standards of ore siliceous fertilizer, ore phosphate fertilizer, by-product lime fertilizer, and special fertilizer (iron-containing) specified by the Fertilizer Control Law. .. In addition, since steelmaking slag of about 10 million tons is produced annually in Japan alone, steelmaking slag can be obtained at low cost and material cost can be suppressed. Therefore, paddy rice seeds are coated with such steelmaking slag. Also in the coated seeds according to the present embodiment, steelmaking slag can be used as the main component of the coating layer that covers the surfaces of various seeds as described above.

Steelmaking slag contains iron, but is mainly iron oxide. Therefore, it is not necessary to consider the damage to the seeds due to the heat generated by the oxidation of iron, which is a concern in the seed coating with iron powder as in Patent Document 1. Further, the steelmaking slag has a property of solidifying. The porosity between the steelmaking slag particles is much larger than the porosity between the consolidated iron powder particles even in the consolidated state. Due to the large void ratio in the solidified state, in seeds coated with steelmaking slag, oxygen and water required for seed germination and growth are released from the outside of the coating layer as compared with seeds coated with iron powder. It is possible to reach the seeds inside the coating layer more easily.

In addition, seed covering with steelmaking slag can also be applied to the seeds of plants cultivated in a non-flooded state, which is the focus of this embodiment. Regarding the germination of seeds, in the case of directly sown seeds that germinate without being flooded, it is important that water infiltrates the inside of the coating layer and the coating layer itself has a water retention capacity. The coating with steelmaking slag has a large void ratio between the steelmaking slag particles and has a higher water retention capacity than the iron powder coating, so that it is also suitable for germination of seeds cultivated under non-flooded conditions. Therefore, the coating with iron powder as disclosed in Patent Document 1 is mainly limited to rice seeds cultivated in a flooded state (that is, paddy rice seeds), whereas the coating with steelmaking slag is used. Is also applicable to the direct sowing of seeds of any plant grown without flooding.

● Steel-making slag containing a predetermined component The steel-making slag used as the main component of the coating layer according to the present embodiment is CaO of 25% by mass or more and 50% by mass or less, SiO _{2 of} 8% by mass or more and 30% by mass or less. least 1 mass% 20 mass% of MgO, 1% by mass or more and 25 mass% of _Al 2 _O 3, 1 wt% or more and 8 mass% or less of Mn, and, 0.1 mass% to 5% by weight of P It may further contain at least one selected from the group consisting of ₂ O ₅ .

◇ CaO: 25% by mass to 50% by mass
First, Ca will be described.
When the steelmaking slag comes into contact with water, Ca and Si or Al, which will be described later, are eluted and chemically bonded to each other to exhibit hydraulic slag. The present invention utilizes this hydraulic property to attach and consolidate steelmaking slag to various seeds to coat various seeds. Therefore, in the present invention, Ca is an important element. Ca is also an essential fertilizer element for plants. When the Ca content of fertilizer or steelmaking slag is expressed, the content is expressed in terms of oxide CaO. Therefore, the Ca content is hereinafter referred to as CaO.

In the present embodiment, when the CaO content of the steelmaking slag used for coating various seeds is less than 25% by mass, it is possible that a sufficient amount of Ca cannot be eluted to develop hydraulic slag. On the other hand, steelmaking slag having a CaO content of more than 50% by mass is not produced by a normal steelmaking process and is difficult to obtain. In the present embodiment, the steelmaking slag used for coating various seeds preferably can be stably supplied in a large amount, and is preferably produced by a normal steelmaking process. Therefore, in the present embodiment, the CaO content of the steelmaking slag used for coating various seeds is 25% by mass or more and 50% by mass or less. The CaO content of the steelmaking slag is preferably 38% by mass or more and 50% by mass or less.

The CaO content can be measured by, for example, a fluorescent X-ray analysis method.

◇ SiO ₂ : 8% by mass to 30% by mass
Subsequently, Si will be described.
Si, along with Ca and Al, is an element that contributes to the hydraulic limeness of steelmaking slag. Therefore, Si is also an important element in the present invention. Although Si is not an essential element of plants, it is a very important fertilizer effect element especially for rice seeds such as upland rice. Silicic acid (SiO ₂ ) accounts for about 5% of the dry weight of rice plants. In fertilizers and steelmaking slags, when the Si content is expressed, the content is expressed in terms of the oxide SiO ₂ , so the Si content is hereinafter referred to as SiO ₂ .

In the present embodiment, when the content of SiO ₂ of the steelmaking slag used for coating various seeds is less than 8% by mass, it may not be possible to elute a sufficient amount of Si to develop hydraulic slag. .. On the other hand, steelmaking slag having a SiO ₂ content of more than 30% by mass is not produced by a normal steelmaking process and is difficult to obtain. In the present embodiment, the steelmaking slag used for coating various seeds preferably can be stably supplied in a large amount, and is preferably produced by a normal steelmaking process. Therefore, in the present embodiment, the content of SiO ₂ of the steelmaking slag used for coating various seeds is 8% by mass or more and 30% by mass or less. The content of SiO _{2 in} the steelmaking slag is preferably 12% by mass or more and 25% by mass or less.

The content of SiO ₂ can be measured by, for example, a fluorescent X-ray analysis method.

◇ MgO: 1% by mass to 20% by mass
In general, the MgO content of steelmaking slag is considerably lower than the CaO content. This is because steelmaking slag is slag generated mainly by adding lime to hot metal. The Mg contained in the steelmaking slag is mainly due to the Mg eluted from the refractory bricks in the furnace wall of the converter. Mg, together with Ca, Si and Al, is an element related to the hydraulic limeness of steelmaking slag. However, the contribution of Mg to hydraulic lime, such as the difference between the CaO content and the MgO content contained in the steelmaking slag, is smaller than that of Ca. In the present embodiment, since the steelmaking slag used for coating various seeds contains 25% by mass or more of CaO, it is considered that the hydraulic slag can be basically covered by the CaO contained in the steelmaking slag. However, the presence of MgO can be expected to better exhibit hydraulic limeness. In fertilizers and steelmaking slags, when the Mg content is expressed, the content is expressed in terms of the oxide MgO, so the Mg content is hereinafter referred to as MgO.

Here, steelmaking slag having an MgO content of less than 1% by mass does not occur in a normal steelmaking process. On the other hand, in the steelmaking slag generated in the refractory repair of the converter, the MgO content is close to 20% by mass. However, steelmaking slag having an MgO content of more than 20% by mass does not occur. In the present embodiment, the steelmaking slag used for coating various seeds preferably can be stably supplied in a large amount, and is preferably produced by a normal steelmaking process. Therefore, in the present embodiment, the MgO content of the steelmaking slag used for coating various seeds is preferably 1% by mass or more and 20% by mass or less. The MgO content of the steelmaking slag is more preferably 3% by mass or more and 10% by mass or less.

The MgO content can be measured by, for example, a fluorescent X-ray analysis method.

◇ Al ₂ O ₃ : 1% by mass to 25% by mass
Subsequently, Al will be described.
Al, along with Ca and Si, is an important element for the hydraulic limeness of steelmaking slag. In fertilizers and steelmaking slags, when the Al content is expressed, the content is expressed in terms of the oxide Al ₂ O ₃ , so the Al content is hereinafter referred to as Al ₂ O ₃ .

Steelmaking slag having an Al ₂ O ₃ content of less than 1% by mass and steelmaking slag having an Al ₂ O ₃ content of more than 25% by mass are not produced by a normal steelmaking process and are difficult to obtain. is there. In the present embodiment, the steelmaking slag used for coating various seeds preferably can be stably supplied in a large amount, and is preferably produced by a normal steelmaking process. Further, if the content of Al ₂ O _{3 in} the steelmaking slag is 1% by mass or more, Al can exhibit hydraulicity together with Ca and Si. Therefore, in the present embodiment, the Al ₂ O ₃ content of the steelmaking slag used for coating various seeds is preferably 1% by mass or more and 25% by mass or less. However, when it is desired to further increase the hydraulic hardness and promote the solidification, in the present embodiment, the content of Al ₂ O ₃ of the steelmaking slag used for coating various seeds is set to 10% by mass or more and 25% by mass or less. It is more preferable to do so.

The content of Al ₂ O ₃ can be measured by, for example, a fluorescent X-ray analysis method.

◇ Mn: 1% by mass to 8% by mass
Next, Mn will be described.
Mn is an element that has a fertilizing effect on plants. Steelmaking slag having a Mn content of less than 1% by mass and steelmaking slag having an Mn content of more than 8% by mass are not produced by a normal steelmaking process and are difficult to obtain. In the present embodiment, the steelmaking slag used for coating various seeds preferably can be stably supplied in a large amount, and is preferably produced by a normal steelmaking process. Therefore, in the present embodiment, the Mn content of the steelmaking slag used for coating various seeds is preferably 1% by mass or more and 8% by mass or less.

The Mn content can be measured by, for example, a fluorescent X-ray analysis method.

◇ P ₂ O ₅ : 0.1% by mass to 5% by mass
Next, P will be described.
P is an essential element of the plant. The fertilizer and steel slag, when denoted the content of P, since the amount contained in terms of P ₂ O ₅ oxide is denoted, for steel slag used in the coating of various seeds in this embodiment Also represents the content as P ₂ O ₅ . P is an element that acts on the root growth point and has an effect on root growth. When P is insufficient, root growth is suppressed. However, steel slag content of P ₂ O ₅ is less than 0.1 wt%, and, steelmaking slag content of P ₂ O ₅ is 5 wt% excess is not generated in the normal steel manufacturing process, It is difficult to obtain. In the present embodiment, the steelmaking slag used for coating various seeds preferably can be stably supplied in a large amount, and is preferably produced by a normal steelmaking process. Accordingly, in the present embodiment, the content of P ₂ O ₅ of steel slag used in the coating of various seed is preferably 5 mass% or less than 0.1 wt%.

The content of P ₂ O ₅ can be measured by, for example, a fluorescent X-ray analysis method.

Since the CaO content of such steelmaking slag is 25% by mass or more and 50% by mass or less, it exhibits alkalinity of about pH 11. Therefore, when birds and beasts contain seeds having a coating layer containing such steelmaking slag in their mouths, the birds and beasts spit out the seeds without swallowing due to the alkalinity of the steelmaking slag. As a result, it becomes possible to suppress feeding damage caused by birds and beasts.

In addition, the seeds coated with such steelmaking slag germinate even though the steelmaking slag is alkaline. The reason why seeds germinate despite being alkaline is that acidic substances capable of chelating iron ions are secreted from the roots, and the alkali caused by the steelmaking slag that covered the seeds is neutralized, resulting in normal germination. It is believed that it is possible. Further, it is considered that the secretion of such an acidic substance causes iron contained in the steelmaking slag to be chelated as iron ions and easily absorbed from the radicles.

● Derinsing slag and decarburizing slag In this embodiment, the steelmaking slag used for coating various seeds is a steelmaking process using a blast furnace and a converter in addition to the steelmaking slag containing the above-mentioned predetermined components. It is also possible to use derinsed slag, decarburized slag, or the like, which is a kind of converter steelmaking slag produced as a by-product. Dephosphorus slag is a slag containing phosphorus that is produced as a by-product by adding lime, iron oxide, etc. as a dephosphorizing agent to the hot metal and blowing a gas such as oxygen in order to remove phosphorus contained in the hot metal. , A type of steelmaking slag. Further, the decarburized slag is a slag produced by blowing oxygen into the hot metal in order to remove carbon contained in the hot metal to make steel, and is a kind of steelmaking slag.

The derinsed slag and decarburized slag as described above also contain the same components as the steelmaking slag containing the above-mentioned predetermined amount of components, but the content is the same as the content of various components in the steelmaking slag. May be different. However, in the case of derinsed slag or decarburized slag, even if a component having a content different from that of the steelmaking slag containing the above-mentioned predetermined amount of the component is present, steelmaking for coating various seeds in the present embodiment. It can be used as a slag.

● Electric furnace steelmaking slag Electric furnace steelmaking slag is not a steelmaking process using a blast furnace and a converter, but a steelmaking slag produced by the ironmaking process using an electric furnace. Such electric furnace steelmaking slag is also a kind of steelmaking slag. General electric furnace steel slag contains CaO of 15% by mass or more and 60% by mass or less, SiO _{2 of} 10% by mass or more and 20% by mass or less, MgO of 2% by mass or more and 10% by mass or less, and 3% by mass or more. In many cases, at least one of Al ₂ O ₃ of 20% by mass or less is contained so that the total is 100% by mass or less. The electric furnace steelmaking slag is used as a steelmaking slag for coating various seeds in the present embodiment even if a component having a content different from that of the steelmaking slag containing the above-mentioned predetermined amount of the component is present. It is possible. By including the electric furnace steelmaking slag in the coating layer, the electric furnace steelmaking slag functions as a binder, and the coating layer can be more reliably consolidated.

In the coating layer according to the present embodiment, the converter steelmaking slag which is at least one of the derinsing slag and the decarburizing slag as described above and the electric furnace steelmaking slag as described above can be used alone. It is also possible to use them in combination as needed.

● Method for measuring the content of each component in steelmaking slag As described above, in the present embodiment, the content of each component in various steelmaking slags used for coating various seeds shall be measured by fluorescent X-ray analysis. Is possible. More specifically, a calibration curve is prepared by measuring in advance the peak intensity of fluorescent X-rays related to the component of interest using a standard sample whose content is known. For a sample whose content is unknown, the content of the component of interest can be specified by measuring the peak intensity of the fluorescent X-ray related to the component of interest and using a calibration curve prepared in advance. ..

The peak of the fluorescent X-ray of interest is not particularly limited, but for example, the fluorescent X-ray peak of Ca, Si, Mg, Al, Fe, Mn, and P may be focused on.

The method for measuring the content of each component in various steelmaking slags is not limited to the above-mentioned fluorescent X-ray analysis method, and other known analysis methods can be appropriately used.

● Particle size of steelmaking slag In the present embodiment, the above-mentioned steelmaking slag adjusted to a predetermined particle size by pulverization or the like can be used as it is for coating various seeds. For crushing these steelmaking slags, known means such as a jaw crusher, a hammer crusher, a rod mill, a ball mill, a roll mill, and a roller mill can be used.

In the present embodiment, the particle size of the steelmaking slag used for coating various seeds is more likely to solidify when the particle size is finer, so it is preferable to make the particle size finer than a predetermined value. As a result of the study by the present inventor, it has been clarified that the steelmaking slag having a particle size adjusted to less than 600 μm tends to have higher adhesion to various seeds and is highly effective. Therefore, it is preferable that the particle size of the steelmaking slag used as the main component of the coating layer according to the present embodiment is less than 600 μm. For example, steelmaking slag is sieved using a sieve having a pore size of 600 μm, and the particle size of the steelmaking slag that has passed through the mesh of the sieve is less than 600 μm. Steelmaking slag with a finer particle size is preferable for improving the adhesion to various seeds, but crushing and classification requires cost and time, so excessive miniaturization is not necessary.

The particle size of the steelmaking slag used for the coating layer is preferably one that passes through a sieve having a pore size of 180 μm and does not pass through a sieve having a pore size of 22 μm. In other words, the particle size of the steelmaking slag used for the coating layer is preferably 22 μm or more and less than 180 μm.

In the case of steelmaking slag that cannot pass through a sieve having a pore size of 180 μm, it may be difficult to cover the seeds because the adhesion to small-sized seeds among various plant seeds is poor. On the other hand, steelmaking slag that passes through a sieve having a pore size of 22 μm has high adhesion to seeds, but increases the risk of dust being sucked into the respiratory organs of workers during seed coating. There is concern that dustproof measures will require costs. Further, there is a concern that the porosity between the steelmaking slag particles becomes small and becomes dense as in the case of iron powder coating, and the permeation of oxygen and water is suppressed. Therefore, it is preferable that the grain size of the steelmaking slag used for seed coating passes through a sieve having a pore size of 180 μm and does not pass through a sieve having a pore size of 22 μm.

When the particle size of the steelmaking slag constituting the coating layer is measured after the fact, the coating layer is peeled from the coated seeds having the coating layer, and the peeled coating layer is transferred to a scanning electron microscope or a transmission electron microscope. It may be measured by a known measuring device such as a microscope.

[About blast furnace slag]
In the steel manufacturing process using a blast furnace that uses natural products such as iron ore, coal, and limestone as raw materials, by-products called slag are generated. By-produced slag is roughly classified into blast furnace slag produced by the ironmaking process in the blast furnace and steelmaking slag produced by the steelmaking process. The steelmaking slag produced as a by-product in the steelmaking process exhibits a strong alkalinity of about pH 11-12, while the blast furnace slag produced as a by-product in the ironmaking process has a pH of about 10 and is weaker in alkalinity than the steelmaking slag. Steelmaking slag and blast furnace slag are both substances that show solidification, although there are differences in the rate of consolidation.

Blast furnace slag produced as a by-product in the steelmaking process has its components analyzed and controlled in the same way as steelmaking slag, and contains various fertilizer effective elements such as Ca, Si, and Mg. Therefore, it is possible to use blast furnace slag as a fertilizer raw material in the same manner as steelmaking slag which has been conventionally used as a fertilizer raw material. Further, as with steelmaking slag, since an extremely large amount of blast furnace slag is produced annually in Japan alone, blast furnace slag can be obtained at low cost and material costs can be suppressed.

Blast furnace slag contains almost no iron. Therefore, it is not necessary to consider the damage to the seeds due to the heat generated by the oxidation of iron, which is a concern in the seed coating with iron powder as in Patent Document 1. Blast furnace slag also has the property of consolidating, as mentioned earlier. The porosity between the blast furnace slag particles is much larger than the porosity between the consolidated iron powder particles, even in the consolidated state. Due to the large void ratio in the solidified state, in seeds coated with blast furnace slag, oxygen and water required for seed germination and growth are released from the outside of the coating layer as compared with seeds coated with iron powder. It is possible to reach the seeds inside the coating layer more easily. Therefore, it is possible to preferably apply seed covering with blast furnace slag to the seeds of plants cultivated in a flooded state.

In addition, seed covering with blast furnace slag can also be applied to seeds of plants cultivated without flooding. Regarding the germination of seeds, in the case of directly sown seeds that germinate without being flooded, it is important that water infiltrates the inside of the coating layer and the coating layer itself has a water retention capacity. Coating with blast furnace slag has a large void ratio between blast furnace slag particles and has a higher water retention capacity than iron powder coating, so it is also suitable for germination of seeds cultivated under non-flooded conditions. Therefore, the coating with iron powder as disclosed in Patent Document 1 is mainly limited to rice seeds cultivated in a flooded state (that is, paddy rice seeds), whereas the coating with blast furnace slag is used. Is also applicable to the direct sowing of seeds of any plant grown without flooding.

Some of the above-mentioned plant seeds are sensitive to the pH of the environment in which the seeds are exposed. For example, legumes have a high pH in the surrounding environment (when they show strong alkalinity). Is more likely to have problems with its growth. Therefore, by using blast furnace slag having a lower pH as the main component of the coating layer, it is possible to further suppress the influence of alkalinity on the seeds as compared with the case of using steelmaking slag, and it is more possible than using steelmaking slag. It is possible to cover many plant seeds.

Further, since such blast furnace slag exhibits weak alkalinity of about pH 10, when birds and beasts contain seeds having a coating layer containing such blast furnace slag in their mouths, because of the alkalinity of the blast furnace slag, birds and animals are seeds. Exhale without swallowing. As a result, it becomes possible to suppress feeding damage caused by birds and beasts.

Furthermore, the seeds coated with such blast furnace slag germinate even though the blast furnace slag is weakly alkaline. The reason why seeds germinate despite being weakly alkaline is that acidic substances such as hydrogen ions and organic acids are secreted from the roots, and the weak alkalinity caused by the blast furnace slag that covered the seeds is neutralized, which is normal. It is considered that various germination is possible.

● Blast furnace slag containing a predetermined component The blast furnace slag having the above characteristics is preferably a blast furnace slag containing the following components. That is, the blast furnace slag, which is the main component of the coating layer according to the present embodiment, contains CaO of 35% by mass or more and 45% by mass or less, SiO _{2 of} 25% by mass or more and 40% by mass or less, and 2% by mass or more and 15% by mass. and following MgO, and 8% by weight to 20% by weight of _Al 2 _{O 3,} at least one of, it is preferred that the total is blast furnace slag containing such that 100% by weight or less.

◇ CaO: 35% by mass to 45% by mass
First, Ca will be described.
When the blast furnace slag comes into contact with water, Ca and Si and Al, which will be described later, are eluted and chemically bonded to each other to exhibit hydraulic slag. The present invention utilizes this hydraulic lime to attach and consolidate blast furnace slag to various seeds to coat various seeds. Therefore, in the present invention, Ca is an important element. Ca is also an essential fertilizer element for plants. When describing the Ca content in fertilizers and steelmaking slag, the content is expressed in terms of oxide CaO. Therefore, the Ca content is also expressed as CaO below for blast furnace slag. And.

In the present embodiment, when the CaO content of the blast furnace slag used for coating various seeds is less than 35% by mass, it is possible that a sufficient amount of Ca cannot be eluted to develop hydraulic slag. On the other hand, blast furnace slag having a CaO content of more than 45% by mass is not produced by a normal steelmaking process and is difficult to obtain. In the present embodiment, the blast furnace slag used for coating various seeds is preferably able to be stably supplied in a large amount, and is preferably produced by a normal ironmaking process. Therefore, in the present embodiment, the CaO content of the blast furnace slag used for coating various seeds is 35% by mass or more and 45% by mass or less. The CaO content of the blast furnace slag is preferably 40% by mass or more and 44% by mass or less.

The CaO content can be measured by, for example, a fluorescent X-ray analysis method.

◇ SiO ₂ : 25% by mass to 40% by mass
Subsequently, Si will be described.
Si, along with Ca and Al, is an element that contributes to the hydraulic limeness of blast furnace slag. Therefore, Si is also an important element in the present invention. Although Si is not an essential element of plants, it is a very important fertilizer effect element especially for rice seeds such as upland rice. Silicic acid (SiO ₂ ) accounts for about 5% of the dry weight of rice plants. In fertilizers and steelmaking slag, when the Si content is expressed, the content is expressed in terms of the oxide SiO ₂ , so the same applies to blast furnace slag below as the Si content as SiO _2. Will be represented.

In the present embodiment, when the content of SiO ₂ of the blast furnace slag used for coating various seeds is less than 25% by mass, it may not be possible to elute a sufficient amount of Si to develop hydraulic slag. .. On the other hand, blast furnace slag having a SiO ₂ content of more than 40% by mass is not produced by a normal steelmaking process and is difficult to obtain. In the present embodiment, the blast furnace slag used for coating various seeds is preferably able to be stably supplied in a large amount, and is preferably produced by a normal ironmaking process. Therefore, in the present embodiment, the content of SiO ₂ of the blast furnace slag used for coating various seeds is 25% by mass or more and 40% by mass or less. The content of SiO _{2 in} the blast furnace slag is preferably 30% by mass or more and 36% by mass or less.

The content of SiO ₂ can be measured by, for example, a fluorescent X-ray analysis method.

◇ MgO: 2% by mass to 15% by mass
Mg, along with Ca, Si and Al, is an element related to the hydraulic limeness of blast furnace slag. However, the contribution of Mg to hydraulic lime, such as the difference between the CaO content and the MgO content contained in the blast furnace slag, is smaller than that of Ca. In the present embodiment, since the blast furnace slag used for coating various seeds contains 35% by mass or more of CaO, it is considered that the hydraulic slag can be basically covered by the CaO contained in the blast furnace slag. However, the presence of MgO can be expected to better exhibit hydraulic limeness. In fertilizers and steelmaking slag, when the Mg content is expressed, the content is expressed in terms of the oxide MgO. Therefore, the MgO content is also expressed as MgO below for blast furnace slag. I will do it.

Here, blast furnace slag having an MgO content of less than 2% by mass and blast furnace slag having an MgO content of more than 15% by mass do not occur in a normal ironmaking process. In the present embodiment, the blast furnace slag used for coating various seeds is preferably able to be stably supplied in a large amount, and is preferably produced by a normal ironmaking process. Therefore, in the present embodiment, the MgO content of the blast furnace slag used for coating various seeds is preferably 2% by mass or more and 15% by mass or less. The MgO content of the blast furnace slag is more preferably 3% by mass or more and 10% by mass or less.

The MgO content can be measured by, for example, a fluorescent X-ray analysis method.

◇ Al ₂ O ₃ : 8% by mass to 20% by mass
Subsequently, Al will be described.
Al, along with Ca and Si, is an important element for the hydraulic limeness of blast furnace slag. In fertilizer and steelmaking slag, when the Al content is expressed, the content is expressed in terms of the oxide Al ₂ O ₃ , so the blast furnace slag is also referred to as Al ₂ O ₃ below. It shall represent the content of Al.

Blast furnace slag content of Al ₂ O ₃ is less than 8 wt%, and blast furnace slag content of Al ₂ O ₃ is 20 mass% excess is not generated in the normal ironmaking process, difficult to obtain Is. In the present embodiment, the blast furnace slag used for coating various seeds is preferably able to be stably supplied in a large amount, and is preferably produced by a normal ironmaking process. Further, if the content of Al ₂ O _{3 in} the blast furnace slag is 8% by mass or more, Al can exhibit hydraulicity together with Ca and Si. Therefore, in the present embodiment, the Al ₂ O ₃ content of the blast furnace slag used for coating various seeds is preferably 1% by mass or more and 25% by mass or less. However, if it is desired to further increase the hydraulic hardness and promote consolidation, the content of Al ₂ O ₃ of the blast furnace slag used for coating various seeds in the present embodiment is set to 10% by mass or more and 25% by mass or less. It is more preferable to do so.

The content of Al ₂ O ₃ can be measured by, for example, a fluorescent X-ray analysis method.

● Blast furnace slow cooling slag and blast furnace granulation slag In this embodiment, the blast furnace slag used for coating various seeds includes blast furnace slag containing the above-mentioned predetermined components, as well as by-products from the steel manufacturing process. It is also possible to use blast furnace slow cooling slag or blast furnace granulated slag, which is a kind of blast furnace slag. Blast furnace slag produced as a by-product from the steel manufacturing process includes blast furnace slow cooling slag and blast furnace granulated slag, which have the same composition but different chemical properties due to differences in manufacturing methods. These two types of slag are a type of blast furnace slag.

The blast furnace slow cooling slag and the blast furnace granulated slag as described above also contain the same components as the blast furnace slag containing the above-mentioned predetermined amount of components, but the content is the same as that of the various components in the blast furnace slag. It may differ from the content. However, in the case of blast furnace slow cooling slag or blast furnace granulated slag, various seeds are coated in the present embodiment even if a component having a content different from that of the blast furnace slag containing the above-mentioned predetermined amount of component is present. It can be used as a blast furnace slag for.

Here, from the viewpoint of the consolidation property of each slag, the blast furnace granulated slag has higher consolidation property than the blast furnace slow cooling slag. Therefore, it is more preferable to use blast furnace granulated slag as the blast furnace slag for coating various seeds in the present embodiment.

Further, by mixing the steelmaking slag that functions as an alkali stimulant with the blast furnace granulated slag, it is possible to further increase the consolidation rate of the coating layer according to the present embodiment and to solidify the coating layer more stably. It becomes. At this time, the amount of steelmaking slag mixed with the blast furnace granulated slag is not particularly specified, but is preferably about 1% by mass to 20% by mass with respect to the total mass of the blast furnace granulated slag, for example. .. Further, the steelmaking slag to be mixed with the blast furnace granulated slag is not particularly specified, and known steelmaking slag produced by the converter steelmaking process, including derinsing slag and decarburized slag, can be used.

● Method for measuring the content of each component in blast furnace slag As described above, in the present embodiment, the content of each component in various blast furnace slags used for coating various seeds shall be measured by fluorescent X-ray analysis. Is possible. More specifically, a calibration curve is prepared by measuring in advance the peak intensity of fluorescent X-rays related to the component of interest using a standard sample whose content is known. For a sample whose content is unknown, the content of the component of interest can be specified by measuring the peak intensity of the fluorescent X-ray related to the component of interest and using a calibration curve prepared in advance. ..

The peak of the fluorescent X-ray of interest is not particularly limited, but for example, the peak of the fluorescent X-ray of Ca, Si, Mg, Al or the like may be focused on.

The method for measuring the content of each component in various blast furnace slags is not limited to the above-mentioned fluorescent X-ray analysis method, and other known analysis methods can be appropriately used.

● Particle size of blast furnace slag In the present embodiment, the above-mentioned blast furnace slag adjusted to a predetermined particle size by crushing or the like can be used as it is for coating various seeds. For crushing these blast furnace slags, known means such as a jaw crusher, a hammer crusher, a rod mill, a ball mill, a roll mill, and a roller mill can be used.

In the present embodiment, the particle size of the blast furnace slag used for coating various seeds is more likely to solidify as the particle size is smaller, so it is preferable to reduce the particle size to a predetermined value or less. As a result of the study by the present inventor, it has been clarified that the blast furnace slag having a particle size adjusted to less than 600 μm tends to have higher adhesion to various seeds and is highly effective. Therefore, the particle size of the blast furnace slag used as the main component of the coating layer according to the present embodiment is preferably less than 600 μm. For example, the blast furnace slag is sieved using a sieve having a pore size of 600 μm, and the particle size of the blast furnace slag that has passed through the mesh of the sieve is less than 600 μm. Blast furnace slag with a finer particle size is preferable in order to improve the adhesion to various seeds, but excessive fineness is not always necessary when crushing and classification require cost and time.

Further, in the present embodiment, the particle size of the blast furnace slag used for the coating layer preferably passes through a sieve having a pore size of 180 μm, more preferably a sieve having a pore size of 75 μm.

In the case of blast furnace slag that cannot pass through a sieve having a pore size of 180 μm, the adhesion to small-sized seeds among various plant seeds is deteriorated, which may make it difficult to cover the seeds. Further, by using the blast furnace slag (hereinafter, also referred to as “blast furnace slag fine powder”) that passes through a sieve having a pore size of 75 μm, it is possible to increase the consolidation speed of the coating layer according to the present embodiment. Even if the particle size of the blast furnace slag is fine, the porosity between the blast furnace slag particles is sufficiently secured, so that the blast furnace slag is not as dense as the iron powder coating, and the permeation of oxygen and water is not suppressed. Therefore, from the viewpoint of solidification, the particle size of the blast furnace slag used for seed coating is preferably one that passes through a sieve having a pore size of 180 μm, and more preferably one that passes through a sieve having a pore size of 75 μm.

When the particle size of the blast furnace slag constituting the coating layer is measured after the fact, the coating layer is peeled from the coated seeds having the coating layer, and the peeled coating layer is transferred to a scanning electron microscope or a transmission electron microscope. It may be measured by a known measuring device such as a microscope.

[About coal ash]
Coal ash (fly ash) is a type of ash produced when coal is burned, and is a substance containing SiO ₂ and Al ₂ O ₃ as main components. Common coal ash contains 40% by mass to 75% by mass of SiO ₂ , 15% by mass to 35% by mass of Al ₂ O ₃ , 2% by mass to 20% by mass of Fe ₂ O ₃ , and 1% by mass. In many cases, at least one of 10% by mass of CaO is contained so that the total is 100% by mass or less, and further, other components such as MgO may be contained. As is clear from such constituents, coal ash contains components similar to steelmaking slag and blast furnace slag, and is a substance that assists consolidation. By incorporating such coal ash into the coating layer, the coal ash functions as a binder, and the coating layer can be more reliably consolidated.

The coal ash contained in the coating layer is preferably coal ash that passes through a sieve having a pore size of 75 μm. In other words, the particle size of the coal ash contained in the coating layer is preferably less than 75 μm. By setting the particle size of the coal ash to less than 75 μm, the solidification rate of the coating layer can be increased, and the coating layer can be consolidated more easily. The smaller the particle size of the coal ash, the more preferable it is. However, since classification requires cost and time, it is not necessary to use excessively fine particles.

The content of coal ash that can be contained in the coating layer is preferably more than 0% by mass and 20% by mass or less with respect to the total mass of the coating layer. If the ratio of coal ash to the total mass of the coating layer exceeds 20% by mass, the ratio of coal ash is too high, which may reduce the degree of solidification and the germination rate of seeds.

● Method for measuring the content of each component in coal ash As described above, in the present embodiment, the content of each component in coal ash used for coating various seeds can be measured by a fluorescent X-ray analysis method. It is possible. More specifically, a calibration curve is prepared by measuring in advance the peak intensity of fluorescent X-rays related to the component of interest using a standard sample whose content is known. For a sample whose content is unknown, the content of the component of interest can be specified by measuring the peak intensity of the fluorescent X-ray related to the component of interest and using a calibration curve prepared in advance. ..

The peak of the fluorescent X-ray of interest is not particularly limited, but for example, the peak of the fluorescent X-ray such as Ca, Si, Fe, and Al may be focused on.

The method for measuring the content of each component in coal ash is not limited to the fluorescent X-ray analysis method as described above, and other known analysis methods can be appropriately used.

[About other components contained in the mixture for forming a coating layer]
-Gypsum, cement, iron powder, waste sugar honey In addition to at least one of the above-mentioned steelmaking slag, blast furnace slag, or coal ash, the coating layer according to the present embodiment contains gypsum, cement, iron powder, etc. In addition, at least one selected from the group consisting of waste sugar slag may be further contained.

● About gypsum and cement Gypsum and cement are substances that have solidifying properties and function as binders. Therefore, by incorporating at least one of such gypsum or cement in the coating layer, the coating layer can be more reliably consolidated.

Here, general cements are CaO of 62% by mass or more and 67% by mass or less, SiO _{2 of} 19% by mass or more and 24% by mass or less, MgO of 0.5% by mass or more and 3% by mass or less, and 2% by mass. At least one of Fe ₂ O _{3 of} % or more and 6% by mass or less and Al ₂ O _{3 of 2} % by mass or more and 7% by mass or less is contained so as to have a total of 100% by mass or less. There are many.

The content of gypsum or cement that can be contained in the coating layer is 20% by mass or less with respect to the total mass of the coating layer (more specifically, the total mass of steelmaking slag, blast furnace slag, and coal ash). preferable. If the ratio of gypsum or cement to the total mass of the coating layer exceeds 20% by mass, the ratio of gypsum or cement is too high, which may reduce the germination rate of seeds.

The gypsum or cement as described above may be mixed with the coating layer, but it is also possible to coat the coating layer with gypsum or cement.

● About iron powder Iron powder is a substance with a large specific gravity. Therefore, by incorporating iron powder in the coating layer, it is possible to increase the weight of the coated seeds and make it difficult for the seeds to run off. The content of iron powder that can be contained in the coating layer is preferably more than 0% by mass and less than 20% by mass, together with the content of Fe alone derived from steelmaking slag and / or blast furnace slag.

● Molasses Molasses is a dark brown liquid that is produced as a by-product when sugar is refined from squeezed juice such as sugar cane. It contains about 70 to 80% sugar, and also contains minerals and vitamins. In addition, molasses is a by-product and can be obtained at low cost. Molasses in particular contains about 2% of potassium necessary for plant cell growth. Potassium is absorbed from the roots of plants and is a necessary component for the growth of plant cells. Therefore, by including molasses in the coating layer, potassium derived from molasses can be supplied from the coating layer, and it can be expected that the growth of seedlings is further promoted. In addition, since molasses has adhesiveness, by incorporating molasses in the coating layer, it is possible to reinforce the solidification of the coating layer and the stability of adhesion to seeds, and the components contained in the molasses after germination. It is possible to promote the growth of radicles in addition to the fertilizer effect of steelmaking slag and blast furnace slag.

Alginic acid compound The coating layer according to the present embodiment may contain a compound derived from alginic acid (alginic acid compound) such as sodium alginate, calcium alginate, magnesium alginate and the like.

Sodium alginate is a type of polysaccharide contained in algae such as brown algae. When Ca or Mg is added to an aqueous solution of sodium alginate, it has the property of gelling. Since steelmaking slag and blast furnace slag contain Ca and Mg, gelation occurs by adding an aqueous solution of sodium alginate to the surface of steelmaking slag and blast furnace slag, and the seeds of the coating layer containing steelmaking slag and blast furnace slag are formed. It is possible to reinforce the stability of adhesion. In addition, when coated seeds prepared using sodium alginate are directly sown in soil, sodium alginate is decomposed by the action of soil microorganisms to become alginate oligosaccharides. Alginate oligosaccharides have the effect of assisting the absorption of minerals into plant roots by binding with minerals contained in the steelmaking slag of the coating layer, and can be expected to have the effect of promoting the growth of seedlings after germination.

The sodium alginate as described above may partially react with the calcium present in the steelmaking slag and may be present in the coating layer as calcium alginate. Similarly, if magnesium is present in the blast furnace slag, sodium alginate may partially react with magnesium in the blast furnace slag and be present in the coating layer as magnesium alginate. Therefore, when sodium alginate is permeated into the coating layer according to the present embodiment, not only sodium alginate but also calcium alginate and magnesium alginate may be present in the coating layer. Similar to sodium alginate, these calcium alginate and magnesium alginate are also decomposed by the action of soil microorganisms to become alginate oligosaccharides. Alginate oligosaccharides have the effect of assisting the absorption of minerals into plant roots by binding with minerals contained in steelmaking slag and blast furnace slag of the coating layer, and can be expected to have the effect of promoting the growth of seedlings after germination.

[About the porosity of the coating layer]
The porosity of the coating layer containing various steelmaking slags as described above is preferably 17 to 50%. The porosity of the coating layer can be controlled to a desired value by adjusting the particle size of the steelmaking slag contained in the coating layer, and the specific value of the porosity is appropriately set for the seed. It may be adjusted as appropriate. In order to preferably maintain oxygen supply and water retention, the porosity of the coating layer is preferably 20 to 40%, more preferably 20 to 30%.

The porosity of the coating layer can be measured as follows.
First, a seed having a coating layer is embedded in various resins and polished by a known method to prepare a measurement sample. Next, the cross section of the coating layer in the obtained measurement sample is observed with an optical microscope set to a predetermined magnification, and the area of pores occupying the area of the seed coating in the visual field is calculated and used as the porosity. .. The observation is carried out in a plurality of visual fields (for example, about 5 visual fields), and the average value of the porosity obtained in each visual field between the plurality of visual fields is obtained and used as the porosity of the covering layer. Since the coating layer and the drug layer described later have distinctly different particle size homogeneity, it is possible to distinguish between them by microscopic observation. Further, in order to distinguish between the two more reliably, for example, an electron probe microanalyzer (EPMA) can be used. This makes it possible to distinguish between the coating layer and the drug layer by distinguishing the constituent elements of the coating layer and the drug layer.

The coating layer in the coated seed according to the present embodiment has been described in detail above.

<About the drug layer>
It is known that most of the chemicals (pesticides) such as disinfectants, insect repellents, and herbicides, which are organic substances of interest in the coated seeds according to the present embodiment, are strongly alkaline and decompose. Therefore, when carrying a drug such as a disinfectant, an insect repellent, or a herbicide in the drug layer of the coated seed according to the present embodiment, it is important to prevent the drug component from being exposed to strong alkalinity. is there. Here, the steelmaking slag, the blast furnace slag, and the coal ash used as the main components of the coating layer are alkaline at pH 11-12, pH 10-11, and pH 11-12, respectively. Therefore, alkaline and easily decomposed chemicals cannot be mixed with steelmaking slag, blast furnace slag, and coal ash, which are the main components of the coating layer.

Therefore, in the coated seeds according to the present embodiment, the seeds are first coated with a coating layer containing the above-mentioned components, and then a disinfectant, an insect repellent, a herbicide, etc. are applied so as to adhere to the surface of the coating layer. The drug is carried to form a drug layer. This allows these agents, which are harmful to the seed, to be physically blocked by the presence of the coating layer to prevent them from reaching the seed. Further, when the above-mentioned chemicals move toward the seeds in the coating layer, the chemicals are made alkaline by the alkalinity of at least one of the steelmaking slag, the blast furnace slag, or the coal ash contained in the coating layer. It can be decomposed and rendered harmless, and absorption into these harmful drug seeds can be prevented.

When these chemicals are absorbed by seeds, the effect on plant growth is also a problem, but when they are taken into plants, they become residual pesticides and feed on the plants and the crops such as seeds and fruits obtained. There is concern that it will have an adverse effect on humans and various organisms.

Here, even in the seeds coated with iron powder disclosed in Patent Document 1 and the like, in order to avoid direct absorption of the pesticides into the seeds, the seeds are coated with iron powder and then the pesticides are applied to the surface of the coating. It is also conceivable to carry. However, in such a case, the pesticide is only physically blocked from approaching the seed by the coating layer of iron powder, and the seed is detoxified by the chemical such as alkaline decomposition in the coating layer according to the present embodiment. The effect of preventing drug absorption cannot be expected.

In addition, unlike iron powder, steelmaking slag, blast furnace slag, and coal ash used as the main components of the coating layer according to the present embodiment contain disinfectant and insecticidal components derived from various minerals such as quicklime (CaO). Since it is contained, it can exert effects such as sterilization and insect eradication by itself. On the other hand, the effective components for sterilization, insecticide and herbicide of various pesticides as described above are mainly organic substances. Therefore, it can be expected that the effects of sterilization / herbicide / herbicide by organic matter and the effects of sterilization / herbicide by minerals are complementary to each other. Therefore, if the above-mentioned pesticide can be carried on the seeds coated by the coating layer, the effect of at least one of steelmaking slag, blast furnace slag, or coal ash and the effect of the pesticide are complemented. It becomes possible to exert it effectively. Furthermore, in seeds coated with at least one of steelmaking slag, blast furnace slag, or coal ash and carrying pesticides, steelmaking slag, blast furnace slag, and coal ash each contribute to the growth of plant roots after germination. Since it contains elements such as Ca that have a fertilizer effect, it can be expected that the fertilizer effect will further promote the growth of plants after germination, in addition to the sterilization and insecticidal effects.

On the other hand, in seeds coated with iron powder and carrying pesticides, the sterilization / insecticidal effect is the effect of pesticides alone. In addition, the eluted iron ions have no fertilizing effect on the roots after germination, and the iron hydroxide generated from the eluted iron ions covers the surface of the roots after germination, resulting in root growth and water absorption. Harmful because it inhibits mineral absorption.

As described above, seeds coated with at least one of steelmaking slag, blast furnace slag, or coal ash and carrying pesticides are sterilized by at least one of steelmaking slag, blast furnace slag, or coal ash. It can be expected that the insecticidal effect and fertilizer effect and the sterilization / insecticidal / herbicidal effect of the carried pesticide are combined to exert complementary and synergistic effects.

Hereinafter, the drug layer according to the present embodiment having the above-mentioned characteristics will be described in more detail.

In the coated seeds according to the present embodiment, a chemical layer containing at least one of a disinfectant, an insect repellent or a herbicide is provided on the upper layer of the coating layer as described above. These chemicals supported on the surface of the coating layer as a chemical layer realize the medicinal effect of the corresponding chemical on the soil in which the coated seeds are sown or the coated seeds themselves.

◇ About disinfectant The disinfectant that can be supported as a drug layer is not particularly limited as long as it can be used for seeds used as a material for coated seeds, and various known disinfectants. Can be used. Examples of such disinfectants include dithiocarbamate-based disinfectants such as thiuram, isothienyl, flametopyl, etaboxam, 2-[(2,5-dimethylphenoxy) methyl] -α-methoxy-N-methyl-benzeneacetamide. , Benomyl, oxolinic acid, probenazole, thiazinyl, pyrochyron and diclosimet.

◇ Insect repellent The insect repellent that can be supported as a drug layer is not particularly limited as long as it can be used for seeds used as a material for coated seeds, and various known insect repellents. Can be used. As such an insect repellent, for example, it is selected from the group consisting of organophosphorus insect repellents such as fenitrothion, clothianidin, nitenpyram, benzultap, thiamethoxam, dinotefuran, pimetrodin, sulfoxaflor, benfracarb, carbosulfan and cartap hydrochloride. One or more can be mentioned.

◇ About herbicides The herbicides that can be supported as a drug layer are not particularly limited as long as they can be used for seeds used as materials for coated seeds, and various known herbicides should be used. Is possible. Examples of such herbicides include paraquat-based herbicides such as paraquat dichloride.

In addition to the above herbicides, carbamate compounds such as esprocarb, pyribuchicarb, benchocurve, and molinate, acidamide compounds such as etobenzanide, cafentrol, tenylchlor, butacrol, pretilachlor, bromobutide, and mephenacet, and dinitroaniline compounds such as triflularin. , Azim sulfuron, imazosulfuron, ethoxysulfuron, cyclosulfamron, halosulfuron methyl, pyrazosulfuron ethyl, flucetosulfuron, propyrisulfuron, benzulfuron methyl, sulfonylurea compounds such as thifensulfuron methyl, pyrimisulfan, etc. Symphonanilide compounds, diazine compounds such as bentazone, oxadiazone, oxadiargyl, pyracronyl, pyrazoxifene, pyrazolate, pyraflufenethyl, benzophenap and other diazole compounds, dimetamethrin, simethrin, promethrin and other triazine compounds, tefryl. Triketone compounds such as trione and mesotrione, urea compounds such as cumyllon and dimulon, bipyridium compounds such as diquat and paracoat, pyrimidyloxybenzoic acid compounds such as bispyrivac sodium salt, pyriminobacmethyl and penoxslam, 2,4 -D, MCPA, Kizarohop, Chromeprop, Sihalohop, Sihalohopbutyl, Haroxyhop, Clozinahop and other phenoxy acid compounds, Isoxaflutor and other isoxazole compounds, Imazetapill and other imidazolinone compounds, Butamiphos and other organic phosphorus compounds Use one or more selected from the group consisting of compounds, aromatic carboxylic acid compounds such as dicamba, indanophan, oxadichromephone, calfentrazone ethyl, quinocramine, pyriphthalide, fentrazamide, benzobicyclon, pentoxazone, and benfresate. Is possible.

The above-mentioned compounds of the disinfectant, the insect repellent, and the herbicide are all known compounds, and commercially available preparations can be used, or they can be produced by a known production method.

In the present embodiment, the above-mentioned agent is usually a mixture of an active ingredient and an inert carrier, and if necessary, a surfactant or other formulation auxiliary agent is added to a powder, a flowable agent, or water. It is preferable to use those formulated in Japanese preparations, granule wettable powders, aqueous solvents, granular aqueous solvents and the like. Further, a preparation in which the elution of the active ingredient is controlled may be used.

Examples of the inert carrier used in the formulation include solid carriers and liquid carriers.
Examples of solid carriers include clays (kaolin dray, diatomaceous soil, bentonite, fubasami clay, acidic white clay, etc.), synthetic silicon hydroxide-containing talc, ceramics, and other inorganic minerals (serisite, quartz, sulfur, activated charcoal, calcium carbonate, water). Fine powders and granules such as Japanese silica), chemical fertilizers (sulfur-an, phosphorus-an, glass-an, urea, salt-an, etc.), and synthetic resins (polypropylene, polyacrylonitrile, polymethylmethacrylate, polyethylene terephthalate, etc.) , Nylon resin such as Nylon-6, Nylon-11, Nylon-66, Polyamide resin, Polyvinyl chloride, Polyvinylidene chloride, Vinyl chloride-propylene copolymer, etc.).
Examples of the liquid carrier include water, alcohols (methanol, ethanol, isopropyl alcohol, butanol, hexanol, benzyl alcohol, ethylene glycol, propylene glycol, phenoxyethanol, etc.), ketones (acetone, methyl ethyl ketone, cyclohexanone, etc.), and aromatics. Hydrocarbons (toluene, xylene, ethylbenzene, dodecylbenzene, phenylxysilyl ethane, methylnaphthalene, etc.), aliphatic hydrocarbons (hexane, cyclohexane, kerosene, light oil, etc.), esters (ethyl acetate, butyl acetate, myristic acid, etc.) Isopropyl, ethyl oleate, diisopropyl adipate, diisobutyl adipate, propylene glycol monomethyl ether acetate, etc.), nitriles (acetoyl, isobutyronitrile, etc.), ethers (diisopropyl ether, 1,4-dioxane, ethylene glycol dimethyl ether, etc.) Diethylene glycol dimethyl ether, diethylene glycol monomethyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, 3-methoxy-3-methyl-1-butanol, etc.), acid amides (N, N-dimethylformamide, N, N-dimethylacetamide, etc.) ), Halogenized hydrocarbons (dioxide, trichloroethane, carbon tetrachloride, etc.), sulfoxides (dimethyl sulfoxide, etc.), propylene carbonate and vegetable oils (soybean oil, cottonseed oil, etc.).

Examples of the surfactant include nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl aryl ethers and polyethylene glycol fatty acid esters, and anions such as alkyl sulfonates, alkyl benzene sulfonates and alkyl sulfates. Surfactants can be mentioned.

Other pharmaceutical auxiliary agents include fixing agents, dispersants, coloring agents, stabilizers, etc., specifically casein, gelatin, sugars (temple, arabic gum, cellulose derivatives, alginic acid, etc.), lignin derivatives, bentonite, synthetic. Water-soluble polymers (polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acids, etc.), PAP (isopropyl acid phosphate), BHT (2,6-di-tert-butyl-4-methylphenol), BHA (2-tert-butyl) A mixture of -4-methoxyphenol and 3-tert-butyl-4-methoxyphenol) and the like.

◇ About the content of the drug Here, in the coated seed according to the present embodiment, the content of at least one of the above-mentioned disinfectant, insect repellent or herbicide is the dry mass of the seed before coating. It is preferably 0.01% by mass to 1% by mass. By setting the content of the drug to 0.01% by mass to 1% by mass, the sterilization / herbicide effect and fertilizer effect of the coating layer and the sterilization / herbicide / herbicide effect of the drug layer are complementary. In addition, it is possible to realize it more reliably while combining them synergistically. If the content of the drug is less than 0.01% by mass, the sterilizing, insecticidal, and herbicidal effects of the supported drug may not be sufficiently exhibited, which is not preferable. On the other hand, when the content of the drug exceeds 1% by mass, it may not be possible to suppress the transfer of the carried drug to the seed even when the coating layer according to the present embodiment is provided. Therefore, it is not preferable. In the coated seed according to the present embodiment, the content of at least one of the above-mentioned disinfectant, insect repellent or herbicide is more preferably 0 with respect to the dry mass of the seed before coating. It is 0.05% by mass to 0.5% by mass.

In addition, the drug layer according to the present embodiment may contain an alginic acid compound as described above in addition to the drug components as described above.

The drug layer in the coated seed according to the present embodiment has been described in detail above.

<About the drug coating layer>
In the coated seed according to the present embodiment, in addition to the coating layer and the drug layer, a drug coating layer located on the surface of the drug layer may be provided. Such a drug coating layer allows substances necessary for seed germination and growth, such as water and oxygen, to permeate the seed side, and at least one of the above-mentioned disinfectant, insect repellent or herbicide supported on the drug layer. Is a layer that allows seeds to permeate into the cultivated area where they are cultivated.

Further, by providing such a drug coating layer, it is possible to prevent at least one of the above-mentioned disinfectant, insect repellent or herbicide supported on the drug layer from diffusing into the cultivated area at one time. , The medicinal effect of at least one of the above-mentioned disinfectant, insect repellent or herbicide can be maintained for a longer period of time.

As the material of the drug coating layer, any known material can be used as long as the drug coating layer has a structure having a pore diameter sufficient for the movement of water, oxygen, the above-mentioned drug and the like. is there. Examples of such materials include organic substances such as urethane, ceramics, silica, zeolite, and the like, and these materials can be used in combination.

Here, the amount of the chemical coating layer adhered is preferably 20% by mass to 100% by mass with respect to the dry mass of the seed before coating. By setting the adhesion amount of the drug coating layer to 20% by mass to 100% by mass, it is possible to suppress the diffusion of the above-mentioned drug carried on the drug layer for a longer period of time without hindering the germination and growth of seeds. It becomes. When the amount of the chemical coating layer adhered is less than 20% by mass, the chemical layer cannot be sufficiently retained, and it is difficult to realize an appropriate degree of diffusion of the chemical layer into the cultivated area. May become. On the other hand, when the amount of the chemical coating layer adhered exceeds 100% by mass, the coating layer and the chemical coating layer containing at least one selected from the group consisting of steelmaking slag, blast furnace slag, and coal ash. The thickening of the and may suppress the germination of seeds. The amount of the drug coating layer adhered is more preferably 40% by mass to 80% by mass.

In the drug coating layer according to the present embodiment, the alginic acid compound as described above may be retained in the voids of the material as described above.

The drug-coated layer in the coated seed according to the present embodiment has been briefly described above.

(About the manufacturing method of coated seeds)
Subsequently, the method for producing coated seeds according to the present embodiment will be described in detail.
In the method for producing coated seeds according to the present embodiment, a predetermined seed is coated with a mixture obtained by mixing at least one selected from the group consisting of steelmaking slag, blast furnace slag, and coal ash with water. The steps include treating the seeds coated with such a mixture with an agent containing at least one of a disinfectant, an insecticide, or a herbicide.

<About the step of coating seeds with a mixture>
In the step of coating seeds with a mixture, a predetermined seed is coated with a mixture obtained by mixing at least one selected from the group consisting of steelmaking slag, blast furnace slag, and coal ash with water.

Here, the mass ratio of water in the mixture (that is, the mass ratio of water to the total mass of the mixture) is preferably 10% by mass or more and 80% by mass or less. When the mass ratio of water in the mixture is less than 10% by mass, the adhesion of the slag or the like to the seed surface becomes poor, and there is a high possibility that coating becomes difficult. On the other hand, when the mass ratio of water in the mixture exceeds 80% by mass, the proportion of water is too high, and there is a high possibility that the surface of the seed cannot be covered with the slag or the like. Therefore, the mass ratio of water in the mixture is preferably 10% by mass or more and 80% by mass or less. In order to stably succeed in seed coating using slag or the like, it is more preferable that the mass ratio of water is 25% by mass or more and 50% by mass or less.

Moreover, at least one of gypsum, iron powder, and cement may be mixed with the said mixture. When at least any one of gypsum, iron powder or cement is added to the mixture, it is preferable that the mass ratio of each component does not exceed the content as mentioned above.

Here, when the seed is coated with slag or the like, as mentioned earlier, there is a possibility that the bristles existing on the seed surface weaken the adhesion of the coating layer to the seed surface. In order to solve this phenomenon, the seeds may be soaked in an aqueous starch solution in advance and then coated with slag or the like. Here, the concentration of the starch aqueous solution (that is, the mass ratio of starch to the total mass of the aqueous solution) is preferably 40% by mass to 80% by mass. By immersing the seeds in an aqueous starch solution and then coating the seeds with slag or the like, the ratio of the mass of one seed to the mass of the coating layer can be increased to about 1: 0.6 to 1: 2. It is possible.

Next, a method of coating the plant seeds as described above with the mixture as described above will be described. By preparing a mixture as described above in advance and mixing the mixture with the plant seeds described above, the surface of the seeds used can be coated with slag or the like to form a coating layer on the surface of the seeds. It is also possible to mix the above slag and the like with water and seeds together. The method of mixing the mixture and the seed is not particularly limited. In the case of processing a large amount, for example, it is possible to mix using a rotary granulator and coat the seeds with the above-mentioned slag or the like.

It is also possible to further coat the seeds having a coating layer formed with slag or the like with gypsum from the outside. By double-coating the seeds with slag and gypsum, the adhesion to the seeds due to the coating of slag or the like can be enhanced. As a method of coating the seeds on which the coating layer is formed with gypsum from the outside, for example, the coated seeds coated with slag or the like and dried are immersed in a water suspension of gypsum, taken out, and dried at room temperature. It can be executed by using the method. The concentration of the water suspension of gypsum is preferably, for example, 20% by mass to 60% by mass.

The amount of seeds covered with the above slag or the like is not particularly limited. More preferably, when the mass of the seed is 1, it is preferable to coat the seed with the above-mentioned slag having a mass of about 0.1 to 2. Usually, the coating amount realized only by mixing seeds with a mixture of slag or the like and water falls within the above range. However, when the surface of the seed is not completely covered with the slag or the like, it is preferable to mix the seed with the mixture of the slag or the like and water again.

Further, in order to enhance the solidification of the slag, calcium sulfate, quicklime, slaked lime, etc. are added to either slag, etc., a mixture of slag, etc. and water, or a mixture of slag, etc., water, and seeds. That is also effective.

◇ Water used in the production of coated seeds Here, when the seeds are coated with a mixture of slag and water, the water is mixed with the slag, etc., but in addition to pure water, tap water and groundwater Although it is possible to use water for agriculture, it is more preferable to use water containing waste sugar honey. By using water containing molasses, the stickiness of molasses can be used to reinforce the solidification of the coating layer and the stability of adhesion to seeds, and the components contained in molasses are the components of the slag after germination. Growth can be further promoted in addition to the fertilizer effect of slag.

When the mass ratio of molasses contained in water containing molasses is less than 10% by mass with respect to the total mass, the effect of reinforcing the solidification of the coating layer made of slag or the like and the adhesion stability to seeds is obtained. It becomes difficult to express clearly. On the other hand, when the mass ratio of molasses contained in water containing molasses exceeds 50% by mass with respect to the total mass, slag or the like and water containing this molasses are mixed to produce slag or the like. It becomes a lump and it becomes difficult to adhere to the seeds. Therefore, the mass ratio of molasses contained in water containing molasses is preferably 10% by mass or more and 50% by mass or less with respect to the total mass.

◇ Surface treatment of coated seeds using an aqueous solution of sodium alginate As mentioned earlier, gelation is performed by adding an aqueous solution of sodium alginate to the surface of a coating layer containing at least one of steelmaking slag, blast furnace slag, and coal ash. , And it becomes possible to reinforce the stability of adhesion of the coating layer containing slag and the like to the seeds.

This is a method of adding an aqueous solution of sodium alginate to the surface of the coating layer. For example, by spraying or sprinkling an aqueous solution of sodium alginate on the surface of the coating layer containing slag or the like, alginic acid is added to the surface of the coating layer. There is a method of infiltrating an aqueous sodium solution. It is also possible to immerse the seeds having the coating layer containing slag or the like in the sodium alginate aqueous solution for a short time while being careful not to peel off the coating layer. When the concentration of the sodium alginate aqueous solution is less than 0.5% by mass with respect to the total mass of the aqueous solution, the concentration of sodium alginate is too low, so that gelation does not occur firmly and the coating layer is applied to the seeds. The effect of reinforcing the stability of adhesion may not be exhibited. Further, when the concentration of the sodium alginate aqueous solution exceeds 5% by mass with respect to the total mass of the aqueous solution, the gel becomes too strong and germination may be suppressed. Therefore, the concentration of the sodium alginate aqueous solution added to the surface of the coating layer containing slag or the like is preferably 0.5% by mass or more and 5% by mass or less with respect to the total mass of the aqueous solution. The amount of the sodium alginate aqueous solution when the sodium alginate aqueous solution is sprayed or sprinkled may be an amount that moistens the entire surface of the coating layer.

<Steps to treat seeds coated with mixture with chemicals>
In the method for producing coated seeds according to the present embodiment, the seeds coated with the mixture as described above are treated with an agent containing at least one of a disinfectant, an insect repellent, or a herbicide. The drug treatment step will be described in detail below.

In the drug treatment step according to the present embodiment, a drug containing at least one of a disinfectant, an insect repellent, or a herbicide on the surface of the seed coated with the mixture (that is, the surface of the coating layer). May be supported in contact with each other.

Further, in the chemical treatment step according to the present embodiment, a predetermined spreading agent is attached to the surface of the seeds coated with the mixture, and then the disinfectant is applied to the seeds to which the spreading agent is attached. An insect repellent or an agent containing at least one of the herbicides may be supported in contact.

Further, in the drug treatment step according to the present embodiment, a drug mixture containing a predetermined spreading agent and at least one of a disinfectant, an insect repellent, or a herbicide is prepared in advance and coated with the mixture. Such drug mixture may be attached to the surface of the seeds.

By using any of the above methods, an agent containing at least one of a disinfectant, an insect repellent, or a herbicide is supported on the surface of the coating layer, including an alkaline and easily decomposed pesticide. It can be used as a drug layer.

Here, the above-mentioned spreading agent is not particularly limited, and any known spreading agent can be used. Examples of such spreading agents include liquid paraffin, polyoxyethylene nonylphenyl ether, calcium lignin sulfonate, gypsum, starch, sodium alginate and the like.

Here, when carrying a drug containing at least one of a disinfectant, an insect repellent, or a herbicide, the amount of the drug used can be adjusted so that the content of the drug is within the above range. preferable.

Further, the alginic acid compound can be introduced into the drug layer by infiltrating the surface of the drug layer formed as described above with an aqueous solution of sodium alginate in the same manner as in the case of the coating layer.

<Steps to form a drug coating layer>
Further, in the method for producing coated seeds according to the present embodiment, the surface of the coated seed on which the above-mentioned drug layer is formed is treated with the above-mentioned material to form a drug-coated layer on the surface of the drug layer. It may be formed.

Here, the method of forming the drug coating layer on the surface of the drug layer is not particularly limited, and may be carried out in the same manner as the method of forming the coating layer on the surface of the seed. That is, a mixture containing at least one material selected from the group consisting of an organism, ceramics, silica, and zeolite and water was prepared and obtained in the same manner as in the method for forming a coating layer. The mixture may be used to treat coated seeds with a drug layer.

Further, by infiltrating the surface of the drug coating layer formed as described above with an aqueous solution of sodium alginate in the same manner as in the case of the coating layer, the alginate compound can be supported on the drug coating layer.

In the above description, the composition of slag or the like is shown as the composition before being mixed with water. In order to confirm the composition of the slag after mixing with water, the slag may be recovered in a state where the water is evaporated and dried, and the composition of the recovered slag may be examined. As described above, the composition of the slag before coating and the composition of the slag after coating are almost the same.

Seeds coated with a coating layer containing slag or the like can be used for direct sowing after being air-dried, for example, in a well-ventilated place. It is preferable to sow as soon as possible after the coating, because the coating deteriorates the air permeability and suppresses the respiration of the seeds. If possible, it is preferable to sow within 4 days after coating.

However, it is also possible to store the coated seeds and use them for direct sowing for up to about half a year after coating.

As described above, it is possible to easily and inexpensively produce coated seeds using at least one of steelmaking slag, blast furnace slag, and coal ash.

(About sowing method of covered seeds)
Subsequently, the method of sowing the coated seeds as described above will be briefly described.
In the method of sowing coated seeds according to the present embodiment, the coated seeds as described above are directly sown in the cultivation area for cultivating the seeds.

Here, the sowing method of the coated seed is not particularly limited, and a known sowing method suitable for cultivation of the plant used for the coated seed may be adopted.

Hereinafter, the coated seeds, the method for producing the coated seeds, and the method for sowing the coated seeds according to the present invention will be specifically described with reference to Examples and Comparative Examples. The examples shown below are merely examples of the coated seeds, the method for producing coated seeds, and the method for sowing coated seeds according to the present invention, and the methods for producing coated seeds, coated seeds, and coated seeds according to the present invention. The sowing method is not limited to the following examples. The rice seeds in this example shown below are paddy rice seeds.

(Example 1)
Steelmaking slag having the composition shown in Table 1 below was pulverized and coated with rice seeds and corn seeds using a slag having passed through a sieve having a pore size of 600 μm and iron powder having passed through a sieve having a pore size of 600 μm.

Specifically, a mixture of steelmaking slag and water and a mixture of iron powder and water were prepared, and these mixtures were attached to the surfaces of rice seeds and corn seeds, respectively. Then, the rice seeds and corn seeds to which the mixture was attached were dried to form a coating layer on the seed surface.

Subsequently, the chiuram wettable powder, which is a disinfectant (dithiocarbamate-based disinfectant), was applied to the rice seeds and corn seeds having these coating layers to the rice seeds and corn seeds before coating the coating layer. The surface of each coating layer was powdered so as to be 0.1% by mass with respect to each dry mass to form a drug layer. As a result, coated rice seeds and coated corn seeds supporting thiuram as a drug layer were obtained. Liquid paraffin was used as a spreading agent for powder coating.

Filter paper is laid on a 90 mm diameter plastic petri dish, and each petri dish is covered with steelmaking slag and has chiuram-supported rice seeds and corn seeds, and iron powder-coated rice seeds and corn that carry chiuram. Twenty seeds were placed on each seed, distilled water was added, and the seeds were allowed to stand at 28 ° C. for a germination test. As a control, similar germination tests were conducted in parallel for uncoated rice seeds and corn seeds. The results of the obtained germination test are shown in Table 2 below.

From the results of germination rate in Table 2, rice seeds and corn seeds coated with steelmaking slag and supported with thiuram had high germination rates as well as uncoated seeds. However, rice seeds and corn seeds coated with iron powder and supported with thiuram had a low germination rate. This low germination rate is considered to be due to the effect of high temperature caused by heat generation due to oxidation of metallic iron.

(Example 2)
50 seeds of rice seeds and corn seeds coated with steelmaking slag and carrying chiuram as a disinfectant, which were prepared in Example 1 above, were dispersed and arranged on a plastic plate, and the plastic plates were arranged. It was placed outdoors under the condition that it was covered with an enclosure so that it would not be affected by the wind. Two weeks later, the number of seeds left uneaten by the bird was counted, and the seed survival rate was calculated. As a control, similar tests were performed in parallel for uncoated rice seeds and corn seeds. The results of the obtained residual rate are shown in Table 3 below.

As is clear from Table 3 above, it was found that both rice seeds and corn seeds coated with steelmaking slag and carrying a disinfectant had a higher residual rate than uncoated seeds and could not be eaten by birds. It was.

(Example 3)
Regarding the rice seeds and corn seeds coated with steelmaking slag and carrying thiuram, and the rice seeds and corn seeds coated with iron powder and carrying thiuram, which were prepared in Example 1 above, thiuram in the plant body. The content was measured.

Specifically, filter paper is laid on a 90 mm diameter plastic petri dish, and each petri dish is covered with steelmaking slag and covered with chiuram-bearing rice seeds and corn seeds, and iron powder to support chiuram. 20 seeds of rice seeds and 20 seeds of corn were placed, distilled water was added, and the mixture was allowed to stand at 28 ° C. for 2 days. Various seedlings that had absorbed water and swollen before germination were collected, and after carefully removing the seed coat to which the coating was attached, the surface of the plant inside the seed coat was washed with pure water. Then, the adhering water on the surface of the plant was removed, and the mass of the plant after removing the adhering water was measured. Each of the 20 specimens of plants was combined, homogenized, and then the thiuram of the liquid extracted with acetonitrile was analyzed by a solid-phase extraction-high performance liquid chromatograph mass spectrometry (LCMS) method. The thiuram content per plant mass obtained is shown in Table 4 below.

As is clear from Table 4 above, rice seeds and corn seeds coated with steelmaking slag and carrying chiuram were coated with iron powder and compared with rice seeds and corn seeds carrying chiuram inside the seed coat. The amount of slag contained in the plant body of corn was small. This has the effect of physically blocking the access of thiuram to the seeds for both coating with steelmaking slag and coating with iron powder, while steelmaking for rice and corn seeds coated with steelmaking slag. It is considered that thiuram was decomposed by the alkalinity of slag, and the absorption of thiuram into the plant was further suppressed.

(Example 4)
The blast furnace granulated slag having the composition shown in Table 5 below was pulverized and prepared by passing through a sieve having a pore size of 75 μm. Using water containing 20% by mass of molasses, a mixture of such blast furnace granulated slag and water containing molasses was prepared, and this mixture was attached to the surfaces of rice seeds, corn seeds and soybean seeds, respectively. I let you. Then, the rice seeds, corn seeds and soybean seeds to which the mixture was attached were dried to form a coating layer on the seed surface.

Subsequently, the coated rice seeds, the coated corn seeds, and the coated soybean seeds were coated with thiuram wettable powder, which is a disinfectant (dithiocarbamate-based disinfectant), before the coating layer was coated with the rice seeds and corn. A drug layer was formed by coating the surface of each coating layer with 0.1% by mass based on the dry mass of seeds and soybean seeds. As a result, coated rice seeds, coated corn seeds and coated soybean seeds carrying thiuram as a drug layer were obtained. Liquid paraffin was used as a spreading agent for powder coating.

A 90 mm diameter plastic chalet is covered with filter paper, and each chalet is covered with coated rice seeds, coated corn seeds and coated soybean seeds coated with blast furnace granulated slag, and coated with blast furnace granulated slag to support chiuram. Twenty 20 seeds each of rice seeds, coated slag seeds and coated soybean seeds were placed, distilled water was added, and the seeds were allowed to stand at 28 ° C. for a germination test. As a control, similar germination tests were conducted in parallel for uncoated rice seeds, corn seeds and soybean seeds. The results of the germination test obtained are shown in Table 6 below.

From the results of germination rate in Table 6, rice seeds, corn seeds and soybean seeds coated with blast furnace granulated slag and carrying chiuram are the same as uncoated seeds and seeds only coated with blast furnace granulated slag. In addition, the germination rate was high. Therefore, it was found that all plant seeds coated with blast furnace granulated slag and carrying a disinfectant had a good germination rate.

(Example 5)
Coated rice seeds, coated corn seeds and coated soybean seeds coated with blast furnace granulated slag prepared in Example 4 above, and coated rice seeds, coated corn seeds and coated with blast furnace granulated slag and carrying chiuram. Fifty soybean seeds were dispersed and arranged in a plastic plate, and the plastic plates were placed in the field under the condition of being covered with an enclosure so as not to be affected by the wind. Two weeks later, the number of seeds left uneaten by the bird was counted, and the seed survival rate was calculated. As a control, similar tests were performed in parallel for uncoated rice seeds, corn seeds and soybean seeds. The results of the obtained residual rate are shown in Table 7 below.

As shown in Table 7, rice seeds, corn seeds and soybean seeds coated with blast furnace granulated slag and carrying a disinfectant have a higher residual rate than uncoated seeds and are eaten by birds. I found that I couldn't.

(Example 6)
The blast furnace granulated slag having the composition shown in Table 5 above was pulverized and prepared by passing through a sieve having a pore size of 75 μm. In addition, rice seeds harvested in paddy fields where stupid seedling diseases occur frequently were prepared. Using a mixture containing 20% by mass of waste sugar honey and the above-mentioned blast furnace granulated slag, the blast furnace granulated slag was attached to the surface of rice seeds collected in a paddy field with frequent occurrence of fool seedling disease. Then, the rice seeds to which the mixture was attached were dried to form a coating layer on the seed surface.

Subsequently, the benomil wettable powder, which is a disinfectant, was added to the coated rice seeds so as to be 0.1% by mass based on the dry mass of the rice seeds before coating the coating layer. The surface was powdered to form a drug layer. As a result, coated rice seeds carrying benomyl as a drug layer were obtained. Benomyl is a fungicide capable of killing the causative bacteria of sapling disease. When powdered, a mixed solution containing polyoxyethylene nonylphenyl ether and calcium lignin sulfonate was used as a spreading agent.

Coated rice seeds coated with blast furnace granulated slag, coated rice seeds coated with blast furnace granulated slag and carrying benomil, and uncoated rice seeds as a control were applied to the paddy soil where rice is being cultivated. , 100 seeds each were directly sown at 10 cm intervals and cultivated for 25 days under flooded conditions. From the cultivation results, the seedling standing rate, which is the ratio of the number of seedlings that stood from each of the 100 seeds that were directly sown, and how many of the seedlings that stood up became the legginess seedlings that are characteristic of stupid seedling disease. The shown growth rate of seedlings was calculated. The results of the obtained seedling standing rate and legginess rate are shown in Table 8 below.

As is clear from the results in Table 8 above, in the uncoated rice seeds, the seedling standing rate was 20% because the directly sown rice seeds were eaten by birds or floated on water and washed away. there were. Among such uncoated rice seeds, the rate of saplings due to stupid seedling disease was as high as 70%.

On the other hand, coated rice seeds coated with blast furnace granulated slag and rice seeds coated with blast furnace granulated slag and carrying benomil were not eaten by birds and did not float on water and run off. Therefore, the seedling standing rate was 60% and 65%, which were higher than the seedling standing rate of uncoated seeds. In addition, the rate of legginess seedlings was 30% for coated rice seeds coated with blast furnace granulated slag, which was lower than 70% for uncoated rice seeds. It is considered that such a result suppresses the action of the causative bacteria of sapling disease to some extent due to the alkalinity caused by lime and the like contained in the blast furnace granulated slag. Furthermore, in rice seeds covered with blast furnace granulated slag and carrying benomyl, the rate of long seedlings decreased to 5%.

(Example 7-Comparison of steelmaking slag and sewage sludge molten slag)
The steelmaking slag having the composition shown in Table 1 was crushed and passed through a sieve having a pore size of 600 μm, and the sewage sludge molten slag having the composition shown in Table 9 below was crushed and passed through a sieve having a pore size of 600 μm. It was used to coat rice seeds and corn seeds, respectively.

Steelmaking slag has the property of solidifying when mixed with water and dried. However, the sewage sludge molten slag cannot be consolidated by itself even if it is mixed with water and dried. Therefore, after adding gypsum, the mixture of sewage sludge molten slag, gypsum and water was dried, and the sewage sludge molten slag was consolidated.

Specifically, a mixture of steelmaking slag and water and a mixture of sewage sludge molten slag, gypsum and water were prepared. The mixing ratio of the steelmaking slag and water was 2: 1 in terms of mass ratio. For sewage sludge molten slag and gypsum, sewage sludge molten slag and gypsum were mixed at a mass ratio of 80:20, and then a mixture of sewage sludge molten slag and gypsum and water were mixed at a mass ratio of 2: 1.

A mixture using the above two types of slag was attached to the surfaces of rice seeds and corn seeds, respectively. Then, the rice seeds and corn seeds to which the mixture was attached were dried to form a coating layer on the seed surface.

Subsequently, the chiuram wettable powder, which is a disinfectant (dithiocarbamate-based disinfectant), was applied to the rice seeds and corn seeds having these coating layers on the rice seeds and corn seeds before coating the coating layer. The surface of each coating layer was powdered so as to be 0.1% by mass with respect to each dry mass to form a drug layer. As a result, coated rice seeds and coated corn seeds supporting thiuram as a drug layer were obtained. Liquid paraffin was used as a spreading agent for powder coating.

Each of the obtained coated seeds was embedded in a resin, polished, and then the cross section of the coated layer was observed with an optical microscope. The porosity of the coating layer in each coating seed was determined with reference to the area of pores occupying the area of the coating observed in the cross section of this coating. The results obtained are shown in Table 10 below.

As mentioned earlier, for both steelmaking slag and sewage sludge molten slag, approximately the same size passing through a 600 μm sieve was used for seed coating. However, as is clear from Table 10 above, the porosity of the coating layer made of steelmaking slag was larger than the porosity of the coating layer made of sewage sludge molten slag. It is considered that this is because the porosity of the coating layer made of sewage sludge molten slag was smaller than that of the coating layer made of steelmaking slag because gypsum was added for consolidation.

The content of thiuram in the plant was measured for rice seeds and corn seeds coated with these steelmaking slags and carrying thiuram, and rice seeds and corn seeds coated with sewage sludge molten slag and carrying thiuram. ..

Specifically, filter paper is laid on a 90 mm diameter plastic petri dish, and each petri dish is covered with steelmaking slag and then supported with chiuram, and rice seeds and corn seeds, and sewage molten sludge and then chiuram. 20 seeds of rice seeds and 20 seeds of slag were placed on the petri dish, distilled water was added, and the seeds were allowed to stand at 28 ° C. for 2 days. Various pre-germination pups that absorbed water and swollen were collected. First, the pH of the coating was measured by bringing the pH test paper into contact with the coating. The measurement results of the pH of the coating are shown in Table 11 below.

Subsequently, after carefully removing the seed coat to which the coating was attached, the surface of the plant inside the seed coat was washed with pure water. Then, the adhering water on the surface of the plant was removed, and the mass of the plant after removing the adhering water was measured. Each of the 20 specimens of plants was combined, homogenized, and then the thiuram of the liquid extracted with acetonitrile was analyzed by a solid-phase extraction-high performance liquid chromatograph mass spectrometry (LCMS) method. The thiuram content per plant mass obtained is shown in Table 12 below.

As is clear from Table 12 above, rice seeds and corn seeds coated with steelmaking slag and supported with thiuram were compared with rice seeds and corn seeds coated with sewage molten sludge and supported with thiuram. , The amount of thiuram contained in the plant inside the seed coat was small. This has the effect of physically blocking the access of thiuram to seeds for both coating with steelmaking slag and coating with sewage sludge molten slag, while for rice and corn seeds coated with steelmaking slag. It is probable that thiuram was decomposed by the alkalinity of the steelmaking slag, and the absorption of thiuram into the plant was further suppressed. In particular, since steelmaking slag has a high porosity, a relatively large amount of alkaline water has entered the pores, and in the process of moving thiuram in this alkaline water, it is decomposed by alkalinity and is decomposed in the plant body. It is probable that the thiuram content in the slag was reduced. On the other hand, sewage sludge molten slag has a lower porosity than steelmaking slag and a lower pH than steelmaking slag, so when thiuram passes through the coating, decomposition does not proceed and thiuram is detected in the plant. It is possible that

Although preferred embodiments of the present invention have been described in detail above, the present invention is not limited to such examples. It is clear that anyone with ordinary knowledge in the field of technology to which the present invention belongs can come up with various modifications or modifications within the scope of the technical ideas described in the claims. , These are also naturally understood to belong to the technical scope of the present invention.

Claims (30)

A coating layer located on the surface of a given seed and containing at least one selected from the group consisting of steelmaking slag, blast furnace slag, and coal ash.
A drug layer located on the surface of the coating layer and containing at least one of a disinfectant, an insect repellent, or a herbicide.
Equipped with a,
Coated seeds , the porosity of the coating layer is 17-50% . The steelmaking slag includes CaO of 25% by mass or more and 50% by mass or less, SiO _{2 of} 8% by mass or more and 30% by mass or less, MgO of 1% by mass or more and 20% by mass or less, and 1% by mass or more and 25% by mass or less. Al ₂ O ₃ of 1 mass% or more and 8 mass% or less, and P ₂ O _{5 of} 0.1 mass% or more and 5 mass% or less, the total is 100 mass% or less. The coated seed according to claim 1, which is contained as described above. The coated seed according to claim 1 or 2 , wherein the steelmaking slag is a converter steelmaking slag or an electric furnace steelmaking slag which is at least one of derinsed slag and decarburized slag. The blast furnace slag contains CaO of 35% by mass or more and 45% by mass or less, SiO _{2 of} 25% by mass or more and 40% by mass or less, MgO of 2% by mass or more and 15% by mass or less, and 8% by mass or more and 20% by mass or less. The coated seed according to any one of claims 1 to 3 , which contains at least one of Al ₂ O ₃ of the above so as to have a total of 100% by mass or less. The coal ash contains CaO of 1% by mass or more and 10% by mass or less, SiO _{2 of} 40% by mass or more and 75% by mass or less, Fe 2O _{3 of 2} % by mass or more and 20% by mass or less, and 15% by mass or more and 35. The coated seed according to any one of claims 1 to 4 , which contains at least one of Al ₂ O _{3 of} mass% or less so as to have a total of 100 mass% or less. The coated seed according to any one of claims 1 to 5 , wherein the steelmaking slag is a steelmaking slag that passes through a sieve having a pore size of 600 μm. The coated seed according to any one of claims 1 to 6 , wherein the blast furnace slag is a blast furnace slag that passes through a sieve having a pore size of 600 μm. The coated seed according to any one of claims 1 to 7 , wherein the blast furnace slag is a blast furnace slag that passes through a sieve having a pore size of 75 μm. The coated seed according to any one of claims 1 to 8 , wherein the coal ash is a coal ash that passes through a sieve having a pore size of 75 μm. The coated seed according to any one of claims 1 to 9 , wherein the content of the coal ash in the coating layer is more than 0% by mass and 20% by mass or less with respect to the total mass of the coating layer. The coated seed according to any one of claims 1 to 10 , wherein the content of the drug is 0.01% by mass to 1% by mass with respect to the dry mass of the seed before coating. The disinfectant is a dithiocarbamate disinfectant, isothianyl, flametopil, etaboxam, 2-[(2,5-dimethylphenoxy) methyl] -α-methoxy-N-methyl-benzeneacetamide, benomyl, oxolinic acid, probenazole. The coated seed according to any one of claims 1 to 11 , which is one or more selected from the group consisting of thiazinyl, pyroquilon and diclosimet. The insect repellent is one or more selected from the group consisting of organophosphorus insect repellents, clothianidin, nitenpyram, benzultap, thiamethoxam, dinotefuran, pimetrodin, sulfoxaflor, benfracarb, carbosulfane and cartap hydrochloride. Item 2. The coated seed according to any one of Items 1 to 12 . The coated seed according to any one of claims 1 to 13 , wherein the herbicide is a paraquat-based herbicide. The coated seed according to any one of claims 1 to 14 , further comprising at least one selected from the group consisting of gypsum, iron powder, cement, and molasses. The method according to any one of claims 1 to 15 , wherein the surface of the drug layer has a drug coating layer made of at least one selected from the group consisting of an organism, ceramics, silica, and zeolite. Covered seeds. The coated seed according to any one of claims 1 to 16 , wherein the seed is a seed of a plant cultivated in a flooded state or a seed of a plant cultivated in a non-watered state. The coated seed according to claim 17 , wherein the seed of the plant cultivated in the flooded state is a seed of a gramineous plant. The coated seed according to claim 18 , wherein the seed of the Gramineae plant is a paddy rice seed. The coated seed according to claim 17 , wherein the seed of the plant cultivated in a non-flooded state is a seed of a gramineous plant, a legume family plant, a Polygonaceae plant, an edible herbaceous plant, or a useful plant. The seeds of the Gramineae plant are upland rice seeds, corn seeds, or wheat seeds.
The seeds of the legumes are soybean seeds or adzuki bean seeds.
The seeds of the Polygonaceae plant are buckwheat seeds,
The seeds of the edible herbaceous plant are carrot seeds, tomato seeds, or sugar beet seeds.
The coated seed according to claim 20 , wherein the seed of the useful plant is a turf seed, a grass seed, a plant seed for green manure, or a flowering tree seed. The coated seed according to any one of claims 1 to 21 , wherein at least one of the coating layer, the drug layer, or the drug coating layer located on the surface of the drug layer further contains an alginic acid compound. .. The coated seed according to any one of claims 1 to 22 , wherein the seed is a seed coated with starch. A step of coating a predetermined seed with a mixture obtained by mixing at least one selected from the group consisting of steelmaking slag, blast furnace slag, and coal ash with water.
A step of treating the seeds coated with the mixture with an agent containing at least one of a disinfectant, an insect repellent, or a herbicide.
Only including,
A method for producing coated seeds , wherein the particle size of the steelmaking slag, the blast furnace slag, or the coal ash is adjusted so that the porosity of the coating layer formed by the mixture is 17 to 50% . The method for producing coated seeds according to claim 24, wherein the steelmaking slag is a steelmaking slag that passes through a sieve having a pore size of 180 μm and does not pass through a sieve having a pore size of 22 μm. The method for producing coated seeds according to claim 24, wherein the blast furnace slag is a blast furnace slag that passes through a sieve having a pore size of 75 μm. The method for producing coated seeds according to any one of claims 24 to 26 , wherein the ratio of the water in the mixture is 10% by mass or more and 80% by mass or less with respect to the total mass of the mixture. The method for producing coated seeds according to any one of claims 24 to 27 , wherein the mixture further comprises at least one selected from the group consisting of gypsum, iron powder, and cement. The method for producing coated seeds according to any one of claims 24 to 28 , wherein the water is water containing 10% by mass or more and 50% by mass or less of molasses. A method for sowing coated seeds, wherein the coated seeds according to any one of claims 1 to 23 are directly sown in a cultivation area for cultivating the seeds.