JPWO2007013219A1 - Iron supply agent for plant for alkaline soil and method for producing the same - Google Patents

Abstract

An object of the present invention is to provide an iron supply agent for a plant for alkaline soil, which can provide an aqueous solution having a high Fe 2+ ion concentration and in which oxidation of Fe 2+ ions is suppressed. The plant iron supply agent for alkaline soil of the present invention comprises an aqueous solution obtained by dissolving ascorbic acid and an iron component. Further, another plant iron supply agent for alkaline soil according to the present invention is obtained by removing water from an aqueous solution obtained by dissolving ascorbic acid and an iron component. These plant fertilizers for alkaline soil are obtained by heating a mixture containing ascorbic acid powder, iron component powder such as FeO powder, and water to dissolve the ascorbic acid powder and iron component powder. It can obtain by the method provided with the melt | dissolution process of obtaining the aqueous solution obtained. The FeO powder to be used is a vacuum after heating a granulated product obtained by granulating iron-containing dust and / or a granulated product obtained by granulating iron-containing dust and a reducing agent. It is preferably obtained by rapid cooling.

Description

The present invention relates to an iron supply agent for plants for alkaline soil and a method for producing the same. More specifically, the present invention relates to an iron supply agent for plants for alkaline soil having a high Fe ²⁺ ion concentration in an aqueous solution state and in which oxidation of Fe ²⁺ ions is suppressed, and a method for producing the same.

It is known that iron is a trace essential element for plants, and when deficient, unique symptoms such as yellowing of leaves and impaired protein synthesis reaction are known. Also, iron is taken up in an ionized state. However, among Fe ions, Fe ³⁺ ions are known to be difficult to obtain a satisfactory effect on plants even if they are supplied. For this reason, the device which supplies iron as Fe2 ⁺ ion conventionally is made | formed. However, Fe ²⁺ ions are easily oxidized to Fe ³⁺ , and it is desired that Fe ²⁺ ions can be stably supplied over a long period of time.
As a composition for supplying iron to this plant, the use of iron powder, converter slag, iron hydroxide and the like has been proposed (for example, see Patent Document 1). Furthermore, a method using a water-soluble inorganic iron salt such as iron sulfate and iron nitrate, a method using an EDTA iron complex with ethylenediaminetetraacetic acid (hereinafter simply referred to as “EDTA”), and the like are known.

JP-A-8-277183

However, most of the iron content eluted from the iron-containing composition described in Patent Document 1 is Fe ³⁺ , and it is considered that it is particularly difficult for plants other than gramineous plants to take up. In addition, Fe ions generated from the water-soluble inorganic iron salt do not easily maintain the Fe ²⁺ state and are easily oxidized to Fe ³⁺ . Furthermore, there is a problem that salt accumulation is caused as in the conventional case. That is, water-soluble inorganic metal salts have long been used as various fertilizers, and the strong acid anions constituting these water-soluble metal salts combine with other elements in the soil to form water-insoluble salts. It has become a problem to accumulate. A water-soluble inorganic iron salt cannot solve this problem. Further, it is substantially trivalent iron that is used as the EDTA iron complex. Moreover, EDTA is a strong chelating agent, and there are concerns about fixing heavy metals in soil to cause soil contamination, and dissolving in groundwater to cause water contamination.

The present invention solves the above-described conventional problems, and has a high Fe ²⁺ ion concentration in an aqueous solution, and the iron supply agent for plant for alkaline soil (hereinafter referred to as “the oxidization of Fe ²⁺ ions”). It is also referred to as “iron supply agent for plants”) and its production method.

The present invention is as follows.
(1) An iron supply agent for plants for alkaline soil, comprising an aqueous solution obtained by dissolving ascorbic acid and an iron component.
(2) The plant iron supply agent for alkaline soil according to (1), wherein the iron component is metallic iron and / or FeO.
(3) The iron supplier for alkaline soil plants according to claim 2, wherein the iron component is FeO.
(4) a said iron component is FeO, and contains a ^{Fe 2+} ions and ^{Fe 3+} ions, in the case where the total of the ^{Fe 2+} ions and the ^{Fe 3+} ions is 100 mass%, the ^{Fe 2+} ions 50 The iron supply agent for plants for alkaline soils according to (1) above, which is -99% by mass.
(5) The iron component is FeO, and the Fe ²⁺ ion concentration of the aqueous solution is measured in a region where the hydrogen ion exponent is 7.0 or more, and then the aqueous solution is left to stand for 120 hours, and again the Fe ²⁺ ion concentration. The ferrous agent for plants for alkaline soil according to (1) above, wherein the concentration after standing is 80% or more of the concentration before standing.
(6) The iron supply agent for plant for alkaline soil as described in said (1) containing a biodegradable binder.
(7) The plant iron supply agent for alkaline soil according to (1) above, which contains a biodegradable extender.
(8) An iron supply agent for alkaline soil plants, wherein water is removed from an aqueous solution obtained by dissolving ascorbic acid and an iron component.
(9) The iron supplier for plants for alkaline soil according to (8) above, wherein the iron component is metallic iron and / or FeO.
(10) The plant iron supply agent for alkaline soil according to (9), wherein the iron component is FeO.
(11) The iron component is FeO, and the aqueous solution obtained by dissolving the plant iron supply agent for alkaline soil contains Fe ²⁺ ions and Fe ³⁺ ions, and the Fe ²⁺ ions and the Fe ³⁺ ions The iron supplier for plants for alkaline soil according to (8) above, wherein the Fe ²⁺ ions are 50 to 99% by mass when the total is 100% by mass.
(12) The iron component is FeO, and the Fe ²⁺ ion concentration of an aqueous solution obtained by dissolving the plant iron supply agent for alkaline soil is measured in a region where the hydrogen ion index is 7.0 or more, and then When the aqueous solution is allowed to stand for 120 hours and when the Fe ²⁺ ion concentration is measured again, the concentration after standing is 80% or more of the concentration before standing, the iron supply for plant for alkaline soil according to (8) above Agent.
(13) The iron supplier for plants for alkaline soil according to (8) above, which contains a biodegradable binder.
(14) The plant iron supply agent for alkaline soil according to (8) above, which contains a biodegradable extender.
(15) An iron supplier for a plant for alkaline soil, characterized in that the matrix is composed of peat and / or clay and is composed of granules containing ascorbic acid and an iron component.
(16) When the total of FeO contained as the peat and / or clay, the ascorbic acid and the iron component is 100% by mass, the ascorbic acid is 1 to 30% by mass, and the FeO is 1 to The iron supply agent for plants for alkaline soil according to the above (15), which is 30% by mass.
(17) It comprises a dissolution step of heating a mixture containing ascorbic acid powder, iron component powder, and water to obtain an aqueous solution obtained by dissolving the ascorbic acid powder and the iron component powder. A method for producing a plant iron supply agent for alkaline soil.
(18) The method for producing an iron supply agent for a plant for alkaline soil according to (17), wherein the iron component powder is iron powder and / or FeO powder.
(19) The method for producing an iron supply agent for a plant for alkaline soil according to (18), wherein the iron component powder is FeO powder.
(20) The method for producing an iron supply agent for a plant for alkaline soil according to (17), further comprising a drying step of removing water from the aqueous solution.
(21) The FeO powder is obtained by vacuum heating a granulated product obtained by granulating iron-containing dust and / or a granulated product obtained by granulating iron-containing dust and a reducing agent. The method for producing an iron supply agent for a plant for alkaline soil according to the above (19), which is FeO powder obtained by vacuum quenching.
(22) A method for producing an iron supply agent for a plant for alkaline soil according to (15) above,
A method for producing an iron supply agent for a plant for alkaline soil, characterized in that the peat and / or clay, ascorbic acid powder, and iron component powder are mixed and then granulated.
(23) The method for producing an iron supplier for an alkaline soil plant according to (22), wherein the iron component powder is iron powder and / or FeO powder.
(24) The method for producing an iron supply agent for a plant for alkaline soil according to (23), wherein the iron component powder is FeO powder.
(25) When the total of the peat and / or clay, the ascorbic acid powder and the FeO powder is 100% by mass, the ascorbic acid powder is 1 to 30% by mass, and the FeO powder is 1 to 30% by mass. %. The method for producing an iron supply agent for a plant for alkaline soil according to (24) above.
(26) The above FeO powder is obtained by vacuum heating a granulated product obtained by granulating iron-containing dust and / or a granulated product obtained by granulating iron-containing dust and a reducing agent. The manufacturing method of the iron supply agent for plants for alkaline soil as described in said (24) which is FeO powder obtained by vacuum quenching.

Water is removed from the aqueous solution obtained by dissolving ascorbic acid and the iron component of the present invention, which is an aqueous solution obtained by dissolving ascorbic acid and the iron component. According to the plant iron supplier for alkaline soil of the present invention, a high Fe ²⁺ ion concentration is obtained particularly when the iron component is FeO. That is, for example, even when water is dissolved in soil, a high Fe ²⁺ ion concentration can be obtained, and iron can be supplied with high probability. In addition, since the obtained Fe ²⁺ ions are effectively suppressed from oxidation, iron can be supplied with high probability. Furthermore, since ascorbic acid is used, there is no environmental impact and it is safe to use.
Further, when the iron component is FeO and has a predetermined Fe ²⁺ ion ratio, iron can be supplied with a particularly high probability.
Furthermore, when the iron component is FeO and the pH is measured in the region of 7.0 or higher, and the Fe ²⁺ ion concentration after standing for a predetermined time is 80% or higher immediately after the start of the measurement, the oxidation is particularly high. And can stably supply Fe ²⁺ ions in the long term.
Moreover, when it contains a biodegradable binder, it can be set as the iron supply agent for plants which has the sustained release property which supplies Fe2 ⁺ stably gradually over a long period of time.
Furthermore, when a biodegradable extender is contained, the Fe ²⁺ supply amount can be easily kept within an appropriate range, and the versatility is excellent.

According to still another iron supply agent for a plant for alkaline soil of the present invention comprising a granule in which ascorbic acid and an iron component are contained in a matrix composed of peat and / or clay, particularly when the iron component is FeO, Oxidation of Fe ²⁺ can be suppressed more reliably, and it can be an iron supplier for plants having a sustained release property that supplies Fe ²⁺ particularly stably and gradually.
Furthermore, when the total of FeO contained as peat and / or clay, ascorbic acid and iron component is 100% by mass, ascorbic acid is 1 to 30% by mass and FeO is 1 to 30% by mass Can be more reliably used as an iron supply agent for plants having sustained release properties.

According to the production method of the present invention including the dissolution step, the plant iron supply agent for alkaline soil according to the present invention consisting of an aqueous solution obtained by dissolving ascorbic acid and an iron component can be stably and reliably obtained. Can do.
Moreover, when the drying process which removes water from aqueous solution is provided, the iron supply agent for plants for alkaline soil of the said other this invention formed by removing water from the aqueous solution obtained by melt | dissolving ascorbic acid and an iron component Can be obtained stably and reliably.
According to still another production method of the present invention including a granulation step, a plant iron supply agent for alkaline soil having a sustained release property using peat and / or clay as a matrix can be stably and reliably obtained. .
Moreover, when the sum total of the FeO powder mix | blended as peat and / or clay, ascorbic acid powder, and an iron component powder is 100 mass%, ascorbic acid powder is 1-30 mass%, and FeO powder is 1-30. When it is the mass%, it can be set as the iron supply agent for plants which has a sustained release property more reliably.
Furthermore, in the production method of the present invention, another production method of the present invention, and still another production method of the present invention, the iron component powder is FeO powder, and this FeO powder is vacuum-quenched after the granulated product is heated in vacuum. In the case of the FeO powder obtained in this way, it is possible to reliably and stably obtain an iron supply agent for plants containing FeO having a particularly high antioxidant property.

It is explanatory drawing which shows the growth condition of the rice of Experimental example 7 using the other iron supply agent for plants which uses a biodegradable extender as a matrix with the growth condition when only a fertilizer is used. Explanatory drawing which shows the growth condition of the above-ground part of the rice of Experimental Examples 9-16 using the other iron supply agent for plants which uses a biodegradable extender as a matrix with the growth condition of Experimental Example 8 using only a fertilizer. It is. It is explanatory drawing which compares and shows the growth condition of the above-ground part of Experimental example 8 using only a fertilizer, and the growth condition of the above-ground part of the rice of Experimental examples 9 and 10. FIG. It is explanatory drawing which compares and shows the growth condition of the above-ground part of Experimental example 8 using only a fertilizer, and the growth condition of the above-ground part of the rice of Experimental examples 11 and 12. FIG. It is explanatory drawing which compares and shows the growth condition of the above-ground part of Experimental example 8 using only a fertilizer, and the growth condition of the above-ground part of the rice of Experimental examples 13 and 14. FIG. It is explanatory drawing which compares and shows the growth condition of the above-ground part of Experimental example 8 using only a fertilizer, and the growth condition of the above-ground part of the rice of Experimental examples 15 and 16. FIG. It is explanatory drawing which shows the growth condition of the root part of the rice of Experimental Examples 9-16 using the other iron supply agent for plants which uses a biodegradable extender as a matrix with the growth condition of Experimental example 8 using only a fertilizer. is there. It is explanatory drawing which compares and compares the growth condition of the above-ground part of Experimental example 8 using only a fertilizer, and the growth condition of the root part of the rice of Experimental examples 9 and 10. FIG. It is explanatory drawing which compares and shows the growth condition of the above-ground part of Experimental example 8 using only a fertilizer, and the growth condition of the root part of the rice of Experimental examples 11 and 12. FIG. It is explanatory drawing which compares and shows the growth condition of the above-ground part of Experimental example 8 using only a fertilizer, and the growth condition of the root part of the rice of Experimental examples 13 and 14. FIG. It is explanatory drawing which compares and shows the growth condition of the above-ground part of Experimental example 8 using only a fertilizer, and the growth condition of the root part of the rice of Experimental examples 15 and 16. FIG.

Hereinafter, the present invention will be described in detail.
[1] Plant Iron Supply Agent for Alkaline Soil The plant iron supply agent for alkaline soil of the present invention (hereinafter simply referred to as “the plant iron supply agent”) is prepared by dissolving ascorbic acid and an iron component. It consists of the aqueous solution obtained by the above.
Another plant iron supplier for alkaline soil of the present invention (hereinafter simply referred to as “the other plant iron supplier”) is water from an aqueous solution obtained by dissolving ascorbic acid and an iron component. It is characterized by being removed. That is, the other iron supply agent for plants is obtained by removing water from the iron supply agent for plants.
Still another plant iron supply agent for alkaline soil of the present invention (hereinafter simply referred to as “this further iron supply agent for plants”) comprises a matrix composed of peat and / or clay, with ascorbic acid and an iron component. It consists of the contained granular material, It is characterized by the above-mentioned.

  The alkaline soil in each of the above inventions is a soil in which 25 ml of distilled water is added to 10 g of air-dried soil, shaken for 1 hour, and the pH of the obtained suspension exceeds 7 when measured. I mean. Accordingly, the alkaline soil includes alkaline soil obtained by alkalizing the original alkaline soil and non-alkaline soil, for example, by fertilization or desertification. Examples of the above-mentioned basic alkaline soil include soil containing various calcareous components such as shell fossil soil, calcareous soil, and sandy soil. These may be used alone or in combination of two or more. Furthermore, a mixed soil of an alkaline soil containing these various calcareous components and a non-alkaline soil, which is an alkaline soil as a whole is also included.

In addition, the “iron component” in each of the above inventions is not particularly limited, and may be an iron compound or metallic iron such as iron powder. The iron compound is not particularly limited, but a compound having divalent iron in the molecule is more preferable. Examples of the iron compound include oxides such as FeO, inorganic salts such as FeSO ₄ , Fe (NO ₃ ) ₂ , and FeCl ₂ , organic salts such as trimethoxy iron, and chelate compounds such as Fe-EDTA and Fe-EDDHA. Is mentioned. As this iron compound, FeO is particularly preferable. Only one iron compound may be used, or two or more iron compounds may be used in combination. Furthermore, metallic iron and one or more iron compounds may be used in combination. The iron component is preferably metallic iron and / or FeO, and more preferably FeO.

(1) Iron supply agent for plants This “ascorbic acid” is an organic acid having a hydroxyl group. This ascorbic acid has no irritating odor, and when an aqueous solution containing ascorbic acid and an iron component is prepared, the Fe ²⁺ ion concentration relative to the ascorbic acid concentration can be increased.

The “aqueous solution” is an aqueous solution obtained by dissolving ascorbic acid and an iron component. That is, the aqueous solution does not contain ascorbic acid that cannot be completely dissolved and an iron component that cannot be completely dissolved. However, this aqueous solution may be a supernatant in a solid-liquid coexisting material containing ascorbic acid that cannot be dissolved and / or an iron component that cannot be dissolved.
Moreover, the solution state in the aqueous solution of ascorbic acid and an iron component is not specifically limited. That is, for example, this aqueous solution can contain an iron ascorbate complex and an ascorbate ion. Among these, it is particularly preferable that an iron ascorbate complex is contained.

  The amount of ascorbic acid dissolved in this aqueous solution is not particularly limited, but usually ascorbic acid per 100 ml of water is 0.05 g or more (preferably 0.5 g to the solubility of ascorbic acid at the temperature of the aqueous solution). On the other hand, the iron component can be blended in an amount of 10 to 25 parts by mass, particularly 20 to 25 parts by mass, with 100 parts by mass of ascorbic acid.

  Moreover, the water which comprises this aqueous solution is not specifically limited, Various water can be used. Highly purified water such as pure water and ion-exchanged water may be used, and water usually used such as tap water, industrial water, agricultural water, and groundwater may be used.

  The method for obtaining this aqueous solution is not particularly limited, but can be obtained by a production method described later. That is, (1) It can be obtained by heating a mixture containing ascorbic acid powder, iron component powder, and water. In addition, (2) It can also be obtained by adding iron component powder to an ascorbic acid aqueous solution in which the entire amount has been dissolved in advance and heating. (3) Further, ascorbic acid powder and iron component powder may be further added to an ascorbic acid aqueous solution in which a predetermined amount has been dissolved in advance and heated. Further, (4) it can be obtained by mixing ascorbic acid powder, iron component powder and water without heating. (5) In addition to the above (1) to (4), when an undissolved ascorbic acid and undissolved FeO are contained, a production method comprising a step of separating them by a method such as filtration can do.

The plant iron supply agent can contain a wood vinegar solution for fungicide. When the wood vinegar is contained, the content of the wood vinegar is preferably 10% by mass or less (usually 5% by mass or more) of the whole iron supply agent for the plant. Furthermore, ultraviolet irradiation can be performed in advance for the same purpose. Although ultraviolet irradiation conditions etc. are not specifically limited, It is preferable to use the ultraviolet-ray with a wavelength of 200-380 nm. Moreover, when performing irradiation, it is preferable to irradiate 72 * 10 < ⁴ > microwatt * s / cm < ² > or more. Furthermore, when storing, it is preferable to store at a low temperature. The temperature is not particularly limited, but is preferably 15 ° C. or lower.
The properties of the plant iron supplier will be described later.

(2) Other iron supply agents for plants This other iron supply agent for plants is obtained by removing water from the aqueous solution.
The above “removal” means an operation of removing a part or all of water from an aqueous solution, but usually the water content with respect to the whole other iron supply agent for plants is 90% by mass or less. In particular, the moisture content is 10% by mass or less (preferably 5% by mass or less) in the case of a solid material, and the moisture content is 60 to 90% by mass (preferably 65 to 85% by mass) in the case of a paste. The other iron supply agent for plants may be a solid material from which substantially all the water has been removed from the aqueous solution, or may be a paste-like material from which a part of the water has been removed from the aqueous solution. Of these, solids are preferred.
The method for removing water is not particularly limited, and means such as reduced pressure heating drying, normal pressure heating drying, non-heating reduced pressure drying, and freeze drying can be used. Of these, drying under reduced pressure is preferred. This is because it is possible to suppress the oxidation of Fe ²⁺ in the process of removing this water. In addition to drying under reduced pressure, drying under a low oxygen partial pressure may be used.

When heating at the time of removing water, the temperature of the aqueous solution is not particularly limited, but is preferably maintained at 120 ° C. or lower. This is because if it exceeds 120 ° C., the Fe ³⁺ ion concentration tends to increase. The temperature of the aqueous solution by this heating is more preferably 100 ° C. or less, still more preferably 90 ° C. or less, and particularly preferably 70 ° C. or less. On the other hand, the lower limit temperature is not particularly limited, and may be any temperature that causes transpiration of water under the pressure when water is removed. For example, the temperature of the aqueous solution is preferably 45 ° C. or higher, more preferably 50 ° C. or higher, further preferably 55 ° C. or higher, particularly preferably 60 ° C. or higher, and particularly preferably 65 ° C. or higher. These upper limit temperature and lower limit temperature at the time of heating can be combined. That is, for example, 45 to 120 ° C is preferable, 50 to 100 ° C is more preferable, and 60 to 70 ° C is still more preferable. Combinations other than these may be used.

  Furthermore, when reducing the pressure when removing water, the pressure is not particularly limited, but is preferably 0.1 to 50 kPa, more preferably 0.1 to 20 kPa, still more preferably 3 to 15 kPa, and particularly preferably 4 to 10 kPa. preferable.

In general, the other iron supply agents for plants can be dissolved in almost all amounts in water having a temperature of 15 ° C. or higher. For example, 0.1 g or more (further 0.1-120 g, especially 0.1-50 g, especially 0.1-15 g) can be dissolved in 100 ml of pure water at a temperature of 25 ° C. The properties of the aqueous solution in which this other iron supply agent for plants is dissolved will be described later.
With respect to the treatment for ascorbic acid, aqueous solution, water, and antifungal treatment in the other iron supply agents for plants, the descriptions in the iron supply agent for plants can be applied as they are.

  The method of using the other iron supply agent for plants is not particularly limited. For example, use methods such as mixing with the soil (in powder form and in a lump form), spreading on the soil (in powder form), and embedding in the soil (in a powder form and in a lump form) can be mentioned.

(3) Matters common to the plant iron supply agent and other plant iron supply agents The aqueous solution in which the plant iron supply agent and the other plant iron supply agent are dissolved in water include Fe ²⁺ ions and When Fe ³⁺ ions are contained, especially when the iron component is FeO, when the total of Fe ²⁺ ions and Fe ³⁺ ions is 100% by mass, Fe ²⁺ ions are 50 to 99% by mass (more preferably 60 to 90% by mass, particularly 70 to 90% by mass). That is, Fe ³⁺ ions are contained in an amount of 1 to 50% by mass (further 10 to 40% by mass, particularly 10 to 30% by mass). That is, an aqueous solution containing Fe ²⁺ at a high concentration can be obtained. However, this Fe ²⁺ ion concentration is a value measured by a measuring method of an example described later. In addition, the Fe ³⁺ ion concentration is obtained by stirring and mixing the iron supply agent in ion-exchanged water at a temperature of 20 ° C. so that the concentration becomes 10 g / liter (about 1.0% by mass) (about 5 minutes stirring), and then Filter with a membrane filter (pore size 1 μm), and immediately after filtration, attach a water quality measurement pack to an ultraviolet / visible light spectrophotometer (manufactured by Shimadzu Corporation, type “UV1240”) and be contained in an aqueous solution. The amount of Fe ²⁺ ions and the total amount of Fe ions were measured and calculated by subtracting the amount of Fe ²⁺ ions from the total amount of Fe ions.

Further, in the aqueous solution in which each of the plant iron supply agent and the other plant iron supply agents is dissolved, particularly when the iron component is FeO, the Fe ²⁺ ion concentration ( mg / liter), and then allowed to stand for 120 hours, and the Fe ²⁺ ion concentration measured again is 80% or more of the Fe ²⁺ ion concentration before standing. That is, it is an iron supplier that can stably hold Fe ²⁺ ions for a long period of time and is excellent in anti-oxidation property that is suppressed from being oxidized to Fe ³⁺ . However, the standing is performed in a dark place at a temperature of 25 ° C. where substantially no ultraviolet rays are applied. This Fe ²⁺ ion content is a value measured by the measurement method of Examples described later.

Moreover, this plant iron supply agent and this other plant iron supply agent can contain a biodegradable binder. By containing a biodegradable binder, the iron supply is gradually released as the binder is decomposed to produce Fe ²⁺ . For this reason, Fe ^<2+> ion can be stably supplied over a long period of time. That is, sustained release properties can be imparted to the plant iron supply agent and the other plant iron supply agents.
As the biodegradable binder, a biodegradable plastic can be used. Examples of biodegradable plastics include polybutylene succinate resins, polylactic acid resins, urea resins, polycaprolactone resins, cellulose resins, starch resins, and polyvinyl alcohol resins. These may use only 1 type and may use 2 or more types together.
The content of the biodegradable binder is not particularly limited, but is 10% by mass or less (more preferably 2 to 7% by mass) when the total amount of the iron supplier for plants and the other iron supplier for plants is 100% by mass. %, Usually 1% by mass or more).

In addition, the plant iron supply agent and the other plant iron supply agents may contain a biodegradable extender. The biodegradable extender is a component other than the binder having biodegradability. Examples of this biodegradable bulking agent include rice husk, snow flora, rice bran, shochu, sake lees, citric acid lees, straw, peat, humus, chicken manure, compost, cow manure and bone meal. These may use only 1 type and may use 2 or more types together. In addition, the biodegradable extender may or may not have a predetermined function for plants. Examples of the component having a predetermined function include components that serve as nutrients for plants.
The content of the biodegradable extender is not particularly limited, but is 50 to 94% by mass (preferably 70 to 94%) when the total amount of the iron supplier for plants and the other iron supplier for plants is 100% by mass. Mass%). If it is this range, even when a trace amount iron supply agent for plants is mixed with a lot of soil, a suitable quantity can be mixed.

  The iron supply agent for plants and the iron supply agent for other plants can contain other components in addition to the biodegradable binder and the biodegradable extender. Other components include lipoic acid, oryza oil, various vitamins, Mn, Zn, Cu, Cr, Si, Mg, Ca, Co, Mo, Ni, B, etc. (for example, metal state, metal oxide) Etc.), and compounds such as S and Cl. These may use only 1 type and may use 2 or more types together. The other components are 10 parts by mass or less when the total of the biodegradable binder and the biodegradable extender contained in the plant iron supplier and the other plant iron supplier is 100 parts by mass. It is preferable to do.

  The method of using the plant iron supply agent and the other plant iron supply agents is not particularly limited. For example, if it is in liquid form, it is sprayed (irrigation to the root of the target plant, etc., foliar spraying, etc.) and immersed (used as a culture solution for hydroponics, soaking the root of the target plant, etc.) , And use methods such as mixing with soil. If it is solid, use it for mixing with soil (powdered or lump), spreading on soil (powdered), filling in soil (powdered or lump) A method is mentioned.

(4) Still other plant iron suppliers using a biodegradable extender as a matrix Still other plant iron suppliers using a biodegradable extender as a matrix include biodegradable extenders. In particular, peat and / or clay are contained. These biodegradable extenders are water-repellent, and when this other plant iron supply is used in alkaline soil, it can be used in other plant iron supplies such as aqueous solutions with high pH from the surroundings. Intrusion is suppressed and the pH is kept low, so that a decrease in solubility of FeO is suppressed, and oxidation of Fe ²⁺ ions is further suppressed. Therefore, Fe ²⁺ ions can be supplied stably over a long period of time. That is, excellent sustained release property can be imparted by the other iron supply agent for plants.

  In addition, this other iron supply agent for plants comprises a granular material in which ascorbic acid and an iron component are contained in a matrix composed of peat and / or clay which is a biodegradable extender having water repellency. The shape of the particles constituting the granular body is not particularly limited, and may be any of a sphere, an ellipsoid, a hemisphere, a cube, a cuboid, a cylinder, a briquette, and the like. Further, the granular body may be a dense body or a porous body. Further, the particle diameter (diameter in the case of a sphere, or maximum pass dimension in the case of other shapes) is preferably 50 mm or less (more preferably 10 mm or less, further preferably 6 mm or less, usually 0.5 mm or more).

Furthermore, in this other iron supply agent for plants using a biodegradable extender as a matrix, the total amount of ascorbic acid, FeO contained as an iron component, and peat and / or clay as biodegradable extenders is 100 mass. %, Ascorbic acid is preferably contained in an amount of 1 to 30% by mass, and FeO is preferably contained in an amount of 1 to 30% by mass. The ascorbic acid content is more preferably 3 to 20% by mass, particularly preferably 7 to 13% by mass, and the FeO content is more preferably 3 to 20% by mass, and particularly preferably 7 to 8% by mass. Thus, reduction in the solubility of FeO is sufficiently suppressed, and be more sufficiently suppressed the oxidation of Fe ²⁺ ions, it can be supplied stably Fe ²⁺ ions over a long period.

As described above, by using a water-repellent biodegradable extender to suppress the contact of iron components such as ascorbic acid and FeO with the external environment, this and other plant iron supply agents can be used in alkaline soil. When this occurs, an increase in pH inside the granular material is suppressed. Thereby, the fall of the solubility of FeO is suppressed. Furthermore, since the oxidation of ascorbic acid by oxygen in the air is also suppressed, the effect of suppressing the oxidation of iron components such as FeO by this ascorbic acid is also obtained, and Fe ²⁺ ions are more stably generated over a long period of time. Can be supplied.

  There is no particular limitation on the method of using the other iron supply agent for plants using the biodegradable extender as a matrix. For example, use methods such as mixing with the soil (in powder form and in a lump form), spreading on the soil (in powder form), and embedding in the soil (in a powder form and in a lump form) can be mentioned.

[4] Method for Producing Plant Iron Supply Agent for Alkaline Soil (1) Method for Producing Plant Iron Supply Agent for Alkaline Soil The production method of the present invention is not particularly limited as described above, and various methods are used. Although it can be used, for example, it comprises a dissolution step of heating a mixture containing ascorbic acid powder, iron component powder, and water to obtain an aqueous solution obtained by dissolving ascorbic acid and the iron component Can do.

  The “ascorbic acid powder” is a powder containing the ascorbic acid as a main component (usually 99% or more in purity), and the purity is not particularly limited. Moreover, when it is a powder form, the particle shape etc. are not specifically limited.

The “iron component powder” is a powder mainly composed of the various iron components. The iron component powder is preferably FeO powder. When the iron component powder is FeO powder, the amount of FeO contained in the FeO powder is not particularly limited, but usually FeO is 50% by mass or more (preferably 65% by mass or more, preferably 100% by mass) with respect to the entire FeO powder. %). As this FeO powder, any FeO powder may be used, and a FeO powder described later (a granulated product obtained by granulating dust containing iron (hereinafter also referred to as “dust”), and / or A granulated product obtained by granulating this dust and a reducing agent, FeO powder obtained by vacuum heating and vacuum quenching), and various commercially available FeO powders can be used. Among these, FeO powder obtained by heating the above-mentioned granulated product in a vacuum and then rapidly cooling in a vacuum is preferable.
As the “water”, any water can be used as described above.

  The charging amount of the iron component powder such as ascorbic acid powder and FeO powder and water in the “mixture” is not particularly limited, but ascorbic acid powder (assuming purity 100%): iron component powder (assuming purity 100%): It is preferably used in a mass ratio of water (assuming purity of 100%) in a ratio of 60 to 90: 7 to 28: 3 to 20, and used in a ratio of 65 to 85:10 to 24: 5 to 17.5. It is more preferable to use at a ratio of 68 to 72:10 to 22:10 to 15.

  In addition to ascorbic acid powder, iron component powder and water, the above mixture may or may not contain other components. When it contains another component, it may be contained in a state dissolved in water, or may be contained in a state not dissolved in water. Examples of other components include methanol and ethanol. By containing these, water can be removed more smoothly even under a reduced pressure environment. Only 1 type may contain these and 2 or more types may contain.

The heating conditions in the “heating” are not particularly limited, but the heating temperature is preferably maintained at 120 ° C. or lower. This is because if it exceeds 120 ° C., the Fe ³⁺ ion concentration tends to increase. The temperature of the aqueous solution by this heating is more preferably 110 ° C. or less, further preferably 105 ° C. or less, and particularly preferably 100 ° C. or less. On the other hand, the lower limit temperature is not particularly limited, and is preferably 40 ° C. or higher, more preferably 50 ° C. or higher, and particularly preferably 60 ° C. or higher. These upper limit temperature and lower limit temperature at the time of heating can be combined. That is, for example, 40 to 120 ° C is preferable, 50 to 110 ° C is more preferable, and 60 to 100 ° C is still more preferable. Combinations other than these may be used. In addition, the pressure conditions in the case of a heating are not specifically limited.
As a result of this heating, more ascorbic acid is dissolved in water, and the dissolved amount of iron components such as FeO is increased accordingly, and the concentration of the target Fe ²⁺ ion or Fe ²⁺ ion complex is considered to be increased.

  In the manufacturing method of this invention, the process of removing a water-insoluble component can be provided after the said melt | dissolution process. Examples of the water-insoluble component include ascorbic acid powder that cannot be completely dissolved and iron component powder that cannot be completely dissolved. Although the removal method is not particularly limited, it can usually be performed by filtration. That is, a filtration step can be provided. The filtration conditions at this time are not particularly limited. For example, it is preferable to use a membrane filter having a pore size of 10 μm or less (more preferably 5 μm or less, more preferably 3 μm or less) as the filtration filter.

Moreover, when obtaining this other iron supply agent for plants, the drying process which removes water from the said aqueous solution can be further provided after the said melt | dissolution process or after the said melt | dissolution process and the said filtration process. The drying conditions in this drying step are not particularly limited, and natural drying may be performed, but it is preferable to use the above-described removal method and drying conditions. That is, it is preferable to remove water by heating under reduced pressure. By heating and gradually reducing the water content, Fe ²⁺ ion components (Fe ²⁺ complex, etc.) that are water-soluble and excellent in antioxidant properties are concentrated, and other iron supply agents for plants can be obtained. it is conceivable that.

  Furthermore, when obtaining the said other iron supply agent for plants, a refinement | purification process can also be further provided. The purification process is a process for purifying water-soluble components. That is, for example, after extracting water from the aqueous solution, the plant iron supplier obtained by contacting with water to dissolve the dissolvable part, and then extracting and extracting water-insoluble components in the same manner as described above And a re-drying step of removing water from the aqueous extraction solution obtained in this extraction step.

(2) The present invention, which uses a biodegradable extender as a matrix, and another method for producing an iron fertilizer for plants according to the present invention. The method is not particularly limited. For example, peat and / or clay, which is a biodegradable extender having water repellency (usually powder or granules), ascorbic acid powder, and iron component powder are mixed. And can be obtained by granulation.
The mixing method is not particularly limited, and dry blending using a mortar mixer, an omni mixer, or the like may be used, and mixing may be performed using a kneader, a wet pan, or the like. Further, the granulation method is not particularly limited, but it is usually granulated by an extrusion method. Moreover, it is preferable that the mixing and granulation are continuously performed by extrusion molding because the process can be simplified. The temperature for the dry blending and extrusion molding is not particularly limited, and may be room temperature (for example, 15 to 35 ° C.) or may be heated to about 40 to 90 ° C. as necessary.
About this ascorbic acid powder and iron component powder, each description in the manufacturing method of the iron supply agent for plants of the said (1) this invention is applicable as it is. However, when the total of FeO powder blended as peat and / or clay, ascorbic acid powder and iron component powder is 100% by mass, the ascorbic acid powder is 1 to 30% by mass, and the FeO powder is 1 to 30% by mass. Blended.
Still another plant iron supplier can be obtained by mixing and granulating peat and / or clay and the other plant iron supplier. The mixing and granulation at this time can be performed in the same manner as described above.
Moreover, when using the said other iron supply agent for plants, the mass ratio of peat and / or clay, ascorbic acid powder, and FeO powder is the same as the above, and this mass ratio is for other plants. It can adjust by the mass ratio of each ascorbic acid powder and FeO powder used when manufacturing an iron supply agent, and the mass ratio of peat and / or clay, and this other iron supply agent for plants.

(3) Production method of FeO powder In the production method of the present invention and other production methods of the present invention, in particular, when FeO powder is used as the iron component powder, this FeO powder is formed by granulating dust containing iron. FeO powder obtained by vacuum heating a granulated product and / or a granulated product obtained by granulating this dust and a reducing agent is preferable.

The FeO powder, in addition to FeO, usually containing _{CaAl 2 O 4, FeAl 2 O} 4, CaFe 2 Si 2 O 6, CaSi 2 O 5 and at least one mixed oxide of the MgFe ₂ O ₄ To do. These double oxides may contain only 1 type and 2 or more types may contain them. Moreover, 0.5-10 mass% is preferable when content of double oxide makes the whole FeO powder 100 mass%. If it is this range, the iron supply agent excellent in antioxidant property can be obtained.
Furthermore, the particle diameter of the particles constituting the FeO powder is not particularly limited, but may be any FeO powder having a particle diameter of 5000 μm or less and mixed with powders having various particle diameters. Furthermore, porous particles may be included.

The “dust containing iron” is one containing iron (dust collection powder or the like). Examples of the iron component include iron oxide, other iron compounds, and metallic iron. Only 1 type may contain these and 2 or more types may contain. The amount of iron contained in the dust is not particularly limited, but usually 30% by mass or more (more preferably 35 to 90% by mass, still more preferably 40 to 80% in terms of metallic iron when the total amount of dust is 100% by mass. Mass%). The dust may contain other components in addition to iron. Examples of other components include Zn, Ni, Cu, and Mn. These may be a single metal or a compound such as an oxide. Furthermore, these may contain only 1 type and 2 or more types may contain.
The shape of the dust containing iron is not particularly limited, and may be small pieces or a mixture of powder and small pieces, but is usually powder. The average particle size of the powder is not particularly limited, but is preferably 3 to 10 μm.

  Examples of the dust containing iron include forged shot dust collected in the forging process and steelmaking dust such as electric furnace dust, blast furnace dust, converter dust, and cupola dust generated in the steel making process. These may use only 1 type and may use 2 or more types together. In particular, dust from which the chlorine content has been removed by washing in advance (part or all) is preferred. In particular, the chlorine content in the dust is preferably 0.5% by mass or less (more preferably 0.4% by mass or less, and still more preferably 0.3% by mass or less).

The “granulated product” contains iron-containing dust or the dust and a reducing agent. Granulation promotes the reduction or oxidation of Fe ₂ O ₃ , Fe ₃ O ₄ and Fe (single) to FeO during vacuum heating.
The shape of the particles constituting the granulated product is not particularly limited, and may be any of a sphere, an ellipsoid, a hemisphere, a cube, a cuboid, a cylinder, a briquette, and the like. Furthermore, the granulated product may be a dense body or a porous body. Further, the particle diameter (diameter when spherical, shortest dimension when other shapes) is preferably 25 mm or less (more preferably 15 mm or less, still more preferably 10 mm or less, usually 3 mm or more).

The “reducing agent” is a component that reduces an iron compound that has been oxidized to a divalent or higher valence. As the reducing agent, metallic iron, a mixture thereof, carbon, a mixture thereof, or the like can be used. In particular, reducing agents used for iron cutting scraps, iron polishing scraps, iron powder, pig iron and steel, various waste materials (tire scraps, wood waste materials, etc.) and the like are preferable. These may use only 1 type and may use 2 or more types together.
The shape of the reducing agent is not particularly limited. However, since it is preferable that the contact area with dust is large, powder, granules, small pieces, and the like are preferable, and powder is particularly preferable. Further, the average particle size is preferably 200 μm or less (preferably 180 μm or less).
The content of the reducing agent in the granulated product is not particularly limited, but when the dust is 100 parts by mass, it is 100 parts by mass or less (more preferably 90 parts by mass or less, more preferably 80 parts by mass or less, usually 30 parts by mass). Above) is preferable.

  The granulated product usually contains a binder. Although the kind of binder is not specifically limited, Alumina cement is preferable. The blending amount is 3 to 20 parts by mass (more preferably 3 to 15 parts by mass, further preferably 3 to 12 parts by mass) when the iron-containing dust or the total of the dust and the reducing agent is 100 parts by mass. Part). In this range, granulation can be performed smoothly and embrittlement of the granulated product can be suppressed.

By performing the “vacuum heating”, the FeO concentration in the FeO powder can be increased. Although the vacuum degree at the time of performing this vacuum heating is not specifically limited, 0.1-13.3 kPa (more preferably 2.6-13.3 kPa, especially preferably 4.0-6.7 kPa) is preferable. In this range, it is possible to effectively suppress the residual metallic iron and oxidation of FeO to Fe ₃ O ₄ or the like. In addition, in an inert gas atmosphere having an oxygen partial pressure equivalent to the oxygen partial pressure in the vacuum atmosphere, the same heating is performed instead of the vacuum heating, whereby a FeO powder having a high FeO concentration can be obtained.

The heating temperature (measured value obtained by measuring the granulated product itself) during vacuum heating is preferably 600 to 1100 ° C (more preferably 800 to 950 ° C). However, when a granulated product contains a reducing agent, it is preferable to set it as 800 degreeC or more. In this range, an FeO powder having a particularly high FeO content can be obtained, and the dust containing iron can be prevented from melting during the heating process.
The heating time is not particularly limited, but is preferably 30 minutes or longer (more preferably 30 minutes or longer and within 6 hours).
When zinc oxide or the like is contained in the dust, it is reduced to metal zinc, which can be recovered by evaporation under a vacuum of 600 ° C. or higher and about 1.56 kPa. Thereby, the purity of FeO can further be improved.

  The granulated product is usually heated using a heat treatment furnace. The heat treatment furnace is not particularly limited as long as it includes at least a heater and can uniformly heat the granulated product to be charged. Examples of the heat treatment furnace include a roller hearth furnace and a rotary kiln. The granulated product is pulverized by, for example, a stirring means having a stirring blade while moving in the heat treatment furnace. This heat treatment furnace may be provided with a recovery device for recovering metallic zinc or the like produced by the reduction. The amount of granulated product input to the heat treatment furnace is not particularly limited, but considering the heat conduction to the entire granulated product heated in the heat treatment furnace, the average height of the granulated product sprayed on the hearth is usually The input amount is preferably 100 mm or less, particularly 80 mm or less, and more preferably 30 mm or less.

  The “vacuum quenching” can cool the high-temperature FeO powder generated by vacuum heating without being oxidized. The degree of vacuum during the vacuum quenching is not particularly limited, but is preferably 13.3 kPa or less (more preferably 6.7 kPa or less, usually 5.3 kPa or more). Further, the temperature lowering rate is not particularly limited, but is preferably 5 to 150 ° C./min. In this vacuum quenching, it is preferable to cool to 300 ° C. or less (more preferably 200 ° C. or less, particularly preferably 150 ° C. or less).

  In particular, for the purpose of obtaining FeO powder having a higher FeO content, it is preferable to use a granulated product containing metallic iron. The content of metallic iron is preferably 5% by mass or more (more preferably 5 to 85% by mass, still more preferably 8 to 50% by mass) when the total amount of iron contained in the granulated product is 100% by mass. . When this granulated product is used, for example, an FeO powder having an FeO content of 80% by mass or more (more preferably 85% by mass or more, particularly 90% by mass or more) with respect to the total iron content can be obtained.

  Dust containing the iron component constituting the granulated product containing metallic iron as described above [(1) and (5)] and a combination of this dust and a reducing agent [(2), (3) and (below) 4)]: (1) only forged shot dust collection powder, (2) mixture of forged shot dust collection powder and metal iron (iron powder, etc.), (3) electric furnace dust and metal iron (iron powder, etc.) (4) a mixture of blast furnace dust and metallic iron (iron powder, etc.), (5) only converter dust, and the like. These may use only 1 type and may use 2 or more types together.

Hereinafter, the present invention will be specifically described by way of examples.
[1] Production of FeO powder Fe 80% by mass (hereinafter abbreviated as%), Zn 0.02%, Ca 0.01%, Mn 0.06%, Si 0.06%, etc. are contained, and the average particle size is 100 μm. It was granulated into a cylindrical shape having a diameter of 8 mm and a length of about 20 mm using 82% of forged shot dust collection powder, 10% of iron powder having an average particle size of 75 μm, 5% of alumina cement, and 3% of bentonite. The obtained granulated product was heated in a vacuum heating tank (roller hearth furnace) at 800 ° C. for 30 minutes, then at 850 ° C. for 30 minutes, and then at 900 ° C. for 1 hour.
Next, vacuum quenching is performed in a vacuum quenching bath at a cooling rate of 20 ° C./min to 400 ° C., and the atmosphere in the vacuum cooling bath is replaced with nitrogen, and further cooling is performed at a cooling rate of 13 ° C./min. The temperature was lowered to room temperature to obtain FeO powder.
When FeO contained in this FeO powder was quantified by a calibration curve prepared in advance by an X-ray diffraction method using a mixed powder obtained by mixing a reagent FeO powder and a silicon powder at a predetermined ratio, the content was 90 mass. %Met.

[2] Stability of Fe ²⁺ ions in aqueous iron ascorbate Examples 1-3
(1) Correlation between pH of iron ascorbate aqueous solution and Fe ²⁺ ion concentration 2.5 g of ascorbic acid was dissolved in 500 ml of distilled water to prepare an ascorbic acid aqueous solution. Thereafter, 1.0 g of the FeO powder produced in the above [1] was added to this aqueous solution, stirred for 30 minutes, and then filtered to remove impurities. Thereafter, 20 milliliters were taken from the filtered aqueous solution and put into five containers, and the pH of the aqueous solution in four of these containers was adjusted to 7.0, 8. Adjusted to 0 and 9.0. In addition, pH of the ascorbic acid aqueous solution which was not adjusted pH was 3.4.

With respect to the three types of ascorbic acid aqueous solutions having different pHs prepared as described above, the Fe ²⁺ ion concentrations were measured at the time of aqueous solution preparation or pH adjustment, and after 24 hours, 48 hours, and 120 hours. In addition, the pH of each aqueous solution was also measured. The Fe ²⁺ ion concentration was measured by phenanthroline spectrophotometry based on JIS K0102. In this measurement, the work was always performed in a room where direct sunlight was not inserted. The results are listed in Table 1.

According to the results in Table 1, it can be seen that in any of Experimental Examples 1 to 3, the pH tends to decrease with time, and the Fe ²⁺ ion concentration is maintained at a high concentration. Ascorbic acid is oxidized under alkaline conditions to dehydroascorbic acid, which is thought to reduce the pH of the aqueous solution, and lowering the pH increases the solubility of FeO, and more FeO dissolves in water. In addition, the ascorbic acid having reducibility suppresses the oxidation of Fe ²⁺ to Fe ³⁺ , and these synergistic effects maintain the Fe ²⁺ ion concentration at a high concentration even when the initial pH is high. Conceivable.

(2) Fe ²⁺ ion concentration when adjusting the pH of the aqueous solution after 120 hours in the above (1) Experimental Examples 4 to 6
For each of the three types of aqueous solutions having different initial pH values in (1) above, after 120 hours have elapsed, the lowered pH is adjusted to an approximate value to the initial pH with an aqueous sodium hydroxide solution, and the respective Fe ²⁺ ion concentrations are adjusted. It was measured. Further, since the pH of each aqueous solution whose pH was adjusted decreased again in 24 hours, the pH was again adjusted to a value approximate to the initial pH with an aqueous sodium hydroxide solution, and each Fe ²⁺ ion concentration was measured. This pH adjustment and measurement of each Fe ²⁺ ion concentration were repeated three times. The results are listed in Table 2.

The values of pH and Fe ²⁺ ion concentration in the first and second pH adjustments in Experimental Examples 4 to 6 are values at the time of pH adjustment (initial values) / values after 24 hours from pH adjustment. In the third pH adjustment, only the initial value was measured.

According to the results in Table 2, when the pH is repeatedly adjusted to the alkaline region, the Fe ²⁺ ion concentration tends to decrease as the pH increases, but the pH decreases with time, and the Fe ²⁺ ion concentration is sufficiently high. It can be seen that the tendency to maintain is the same as in the case of (1) above.

[3] Production and evaluation of plant iron supply agent for alkaline soil (Part 1)
Experimental Example 7
(1) Plant iron supply agent for alkaline soil (A)
10% ascorbic acid (purity 99.8% or more), 7.5% FeO powder produced in [1] above, and 82.5% peat processing soil improver (trade name, manufactured by Nippon Fertilizer Co., Ltd.) "Kumiai hyhumin special name A") was mixed and granulated by extrusion molding to produce a substantially spherical iron supplier for plants for alkaline soil (A) having a particle diameter of 3 to 6 mm.

(2) Evaluation of plant iron supply agent for alkaline soil (A) Growth of rice In each of the five cultivation pots, the following seedling culture soil was introduced and germinated using a petri dish (variety: sunny Japan ) Was planted 3 days after germination and grown using an artificial meteorometer, and the growth promoting action and effects of the plant growth promoter (A) were evaluated.
Fertilizer (manufactured by Chisso Asahi Fertilizer Co., Ltd., trade name “Long Total 70”) is added to 100 parts by mass (hereinafter abbreviated as “part”) of shell fossil soil containing approximately 70% by mass of CaCO ₃ . 1 part was blended.
Seedling culture soil (b); 100 parts of the fossil shell soil was mixed with 1 part of the fertilizer and 0.1 part of the iron supply agent for plants (A).
Seedling culture soil (c): 100 parts of the fossil shell soil was mixed with 1 part of the fertilizer and 1 part of the plant iron supply agent (A).
The artificial meteorological instrument (manufactured by Nippon Medical Instrumentation, model “LH-100S”) is operated by adjusting sunshine for 14 hours (illuminance is 1500 lux, temperature is 25 ° C.) and night is 10 hours (temperature is 20 ° C.). did. In addition, water was only replenished by evaporation. That is, operating conditions were set to simulate growth of upland rice in alkaline soil.

(B) Evaluation Results FIG. 1 is an explanatory view of an image obtained by digital photography 10 days after germination of the growth status of each seedling in the rice growth of (A) [(a in FIG. ), (B) and (c) show the results when the above seedling-growing soils (a), (b) and (c) are used, respectively. ]. According to this explanatory diagram, in the case of (b) using the plant iron supply agent for alkaline soil (A), only the fertilizer was blended even though the blending amount was as small as 0.1 part. It can be seen that the seedlings are taller than (a) and are growing smoothly. Moreover, in (c) which the compounding quantity of the plant iron supply agent (A) for alkaline soil is 1 part, it turns out that the seedling is taller than (b), and it is growing especially smoothly.
In addition, there was also a clear difference in the color tone of each seedling, and the green color of the seedling was stronger in the order of (a) to (b), particularly (c). This suggests that the amount of chlorophyll is higher.

[4] Manufacture and evaluation of plant iron supply agent for alkaline soil (Part 2)
Experimental Examples 8-16
(1) Plant iron supply agent for alkaline soil (B)
The plant iron supply agent for alkaline soil (A) produced in the above [3] and (1) is passed through a sieve having an aperture of 1.0 mm, and the plant iron supply agent for alkaline soil having a particle size of 1.0 mm or less ( B) was obtained.
(2) Plant iron supply agent for alkaline soil (C)
Ascorbic acid (purity 99.8%) 800 g and 2 liters of water were put into a stainless steel beaker and stirred at room temperature (20 ° C.) to dissolve ascorbic acid in water. Thereafter, 100 g of the FeO powder produced in the above [1] was added, and stirring was further continued for 30 minutes. Subsequently, this FeO powder dispersion liquid was filtered using a filter paper, and the filtrate was dried for 72 hours by a drier adjusted to 90 ° C. Thereafter, the obtained paste-like material is cooled to room temperature to form a lump, which is sufficiently pulverized in a mortar, and then passed through a sieve having an opening of 1.0 mm, for alkaline soil having a particle size of 1.0 mm or less. A plant iron supplier (C) was produced.

(2) Evaluation of plant iron supply agent for alkaline soil (A) Growth of rice Rice (cultivar: Nihonbare) rice planted with the following seedling culture soil in each cultivation pot and germinated using a petri dish 20 seeds per pot. The cocoons were embedded in the soil at a depth of about 0.5 cm from the surface. Then, it was made to grow using an artificial meteorograph, and the action and effect of promoting the growth of the above-mentioned plant iron supply agent (A) and the above-mentioned plant iron supply agents (B) and (C) were evaluated.

  The seedlings were grown using an artificial meteorograph (manufactured by Nippon Medical Instrument Co., Ltd., model “LH-100S”). The artificial weather apparatus was operated by adjusting the sunshine to 14 hours (the illuminance was 1500 lux, the temperature was 25 ° C.) and the night was adjusted to 10 hours (the temperature was 20 ° C.). Moreover, what added 50 ml distilled water with respect to 300 ml of shell fossil soil was made into the field capacity, and it irrigated so that the total weight of a pot and the content was maintained at 400 g every day throughout a growth period. Furthermore, thirteen pots were randomly repositioned every day throughout the growing period so that illumination (sunshine) was evenly illuminated.

Experimental Example 8: 1 g of fertilizer (manufactured by Chisso Asahi Fertilizer Co., Ltd., trade name “Long Total 70”) was blended with the fossil shell fossil soil in the pot to prepare a seedling culture soil.
Experimental Example 9: In the shell fossil soil in the pot, 1 g of the fertilizer and the iron fertilizer for plants for alkaline soil (A) (in Table 1, “A” in the column of type and “granule” in the column of property). The same shall apply hereinafter.) 0.1 g was blended to prepare a seedling culture soil.
Experimental Example 10: 1 g of the above fertilizer and the above-mentioned ferrous fertilizer for plants for alkaline soil (B) (in Table 1, “B” in the column of type and “powder” in the property column). The same applies hereinafter.) 0.1 g was blended to prepare a seedling culture soil.
Experimental Example 11: 1 g of the above fertilizer and 1.0 g of the above-mentioned fertilizer for plant for alkaline soil (A) were blended in the shell fossil soil in the pot to obtain a seedling culture soil.
Experimental Example 12: 1 g of the above fertilizer and 1.0 g of the above-mentioned fertilizer for plants for alkaline soil (B) were blended with the fossil shell soil in the pot to obtain a seedling culture soil.
Experimental Example 13: 1 g of the above fertilizer and 2.0 g of the above-mentioned fertilizer for plants for alkaline soil (A) were blended with the fossil shell soil in the pot to obtain a seedling culture soil.
Experimental Example 14: 1 g of the above fertilizer and 2.0 g of the above-mentioned fertilizer for plant for alkaline soil (B) were blended with the fossil shell fossil soil in the pot to obtain a seedling culture soil.
Experimental Example 15: 1 g of the above fertilizer and the above-mentioned ferrous fertilizer for plants for alkaline soil (C) (referred to as “C” in the column of type and “powder” in the column of property in Table 1). The same applies hereinafter.) 0.1 g was blended to prepare a seedling culture soil.
Experimental Example 16: 1 g of the above fertilizer and 1.0 g of the above-mentioned fertilizer for plants for alkaline soil (C) were blended with the fossil shell soil in the pot to obtain a seedling culture soil.

The seedlings were grown as described above, photographed after 54 days from direct sowing of the pods, and the seedlings were harvested. Prior to harvesting, the plant heights of 20 seedlings in each pot were measured. Further, the SPAD value (the green density which is an index of the amount of chlorophyll) was measured using a chlorophyll meter (model “SPAD-502” manufactured by Minolta Co., Ltd.). Sift the root soil at the time of harvest, then dry for 7 days, then sift the root soil again, wipe out almost the whole amount, then take a picture, and also dry the above-ground dry weight and root dry weight (root dry weight) And the total weight).
The results are shown in Table 3 and FIGS.
In addition, about the plant height and SPAD value of a seedling, the average value and standard deviation of 20 seedlings of each pot were described.

(B) Evaluation Results According to Experimental Examples 9 and 10, except for the SPAD value of Experimental Example 10, the results are better than Experimental Example 8 in which the plant iron supplier is not administered (FIG. 2). 3, 7, and 8). Further, in Experimental Examples 9 and 10, growth promotion is not sufficient as compared with Experimental Examples 11 to 14, and it is understood that administration of a larger amount of plant iron supply agent is desirable.

  According to Experimental Examples 11 and 12, the above-ground dry weight and root dry weight are equivalent (see FIGS. 2, 3 and 9), but in Experimental Example 12, the dispersion of SPAD values is small (standard deviation value is low) and stable. is doing. That is, it is presumed that the amount of iron dissolved in the soil is higher when administered as a powder than a granule, and it is easy to contact with the roots of each seedling equally and the variation among seedlings is reduced. On the other hand, according to Experimental Examples 13 and 14, the above-ground dry matter weight and SPAD value are similar, but in Experimental Example 14, the plant height is slightly lower than in Experimental Example 13. This may be because, even in the same dose of 2 g, iron is excessively dissolved and slightly excessive in Experimental Example 14 which is a powder. However, it does not appear to exhibit necrosis, which is iron overload (see FIGS. 2 and 5). Moreover, in Experimental Examples 11 and 12, although the dosage is half that of Experimental Examples 13 and 14, the above-ground dry weight is almost equal, and the root dry weight is lower in Experimental Examples 11 and 12 where the dosage is smaller. Many are excellent (see FIG. 7). This suggests that the dose of the plant iron supply agent (B) is excessive at 2 g.

In Experimental Example 16, both the plant height and the SPAD value are the best among the experimental examples (see FIGS. 2 and 6). In Experimental Example 15 in which the dose of the plant iron supply agent (C) is 1/10 compared to Experimental Example 16, plant height, SPAD value, above-ground dry weight, and root dry weight are all compared to Experimental Example 16. (See FIGS. 2, 6, 7 and 11). Therefore, it is presumed that the supply of iron is not sufficient with the dose of Experimental Example 15. On the other hand, in Experimental Example 16, no iron overload is observed, and therefore, when the iron supply agent for plants (C) is administered in a larger amount, growth may be further promoted.
In Example 15, although the SPAD value is low, the plant height, the above-ground dry weight and the root dry weight are sufficient and excellent. This means that in Example 15, the growth of roots is equivalent to that in Example 16, although the dose is 1/10 of Example 16. That is, it is presumed that iron is preferentially used for the growth of the root part and then used for the growth of the above-ground part.

It should be noted that the present invention is not limited to the description of the above-described embodiments, and can be variously modified embodiments within the scope of the present invention. For example, a mixture obtained by mixing ascorbic acid powder and iron component powder, adding a small amount of water to the mixture, and then removing the water can be used as an iron supply agent for plants for alkaline soil. In this case, the amount of water relative to the ascorbic acid powder is not particularly limited, but usually the water is 5 to 20 parts by mass, more preferably 5 to 15 parts by mass with respect to 100 parts by mass of the ascorbic acid powder. On the other hand, the iron component powder can be blended in an amount of 10 to 25 parts by mass, particularly 20 to 25 parts by mass, when the ascorbic acid powder is 100 parts by mass.
About said ascorbic acid powder and iron component powder, the said description is applicable as it is. Moreover, the moisture content in the solid substance or paste-like substance obtained by using a small amount of water as described above can be set to the same level as the other iron supply agents for plants. Further, the water removal method can be the same as that for the other iron supply agent for plants, and drying under reduced pressure is preferable. Moreover, the temperature at the time of heating when removing water and the pressure at the time of reducing the pressure when removing water can be the same as those of the other iron supply agents for plants.

  The plant iron supply agent for alkaline soil of the present invention is widely used in the field of agriculture and forestry. That is, for example, it is widely used for production of agricultural products, hydroponics, production of horticultural plants, maintenance of vegetation in parks and golf courses, maintenance of forests, and the like. Moreover, it is useful as a plant growth promoter especially in the field of production of various agricultural products. It can also be used to solve food problems by growing plants on barren lands around the world and to improve the global environment by promoting absorption of carbon dioxide.

The present invention is as follows.
(1) and ascorbic acid powder, and FeO powder, by heating a mixture comprising water, Ri Do from an aqueous solution obtained by the ascorbic acid powder and FeO powder is dissolved,
The FeO powder is 50% by mass or more of FeO with respect to the entire FeO powder,
The FeO powder is characterized that you containing _{CaAl 2 O 4, FeAl 2 O} 4, CaFe 2 Si 2 O 6, at least one mixed oxide of CaSi ₂ O ₅ and MgFe ₂ O ₄ Plant iron supply for alkaline soils.
(2) When Fe ²⁺ ions and Fe ³⁺ ions are contained, and the total of the Fe ²⁺ ions and the Fe ³⁺ ions is 100% by mass, the Fe ²⁺ ions are 50 to 99% by mass, and When the Fe ²⁺ ion concentration is measured in a region where the hydrogen ion index is 7.0 or more, and then the aqueous solution is allowed to stand for 120 hours, and the Fe ²⁺ ion concentration is measured again , the concentration after standing still 80% or more of the concentration before placement,
The mixture includes ascorbic acid powder, FeO powder, and water in a mass ratio of 60 to 90: 7 to 28: 3 to 20,
The FeO powder is vacuum-cooled after vacuum heating of a granulated product obtained by granulating iron-containing dust and / or a granulated product obtained by granulating iron-containing dust and metallic iron. FeO powder obtained by
The iron supply agent for plants for alkaline soil according to (1), wherein the iron content contained in the dust containing iron is 30% by mass or more in terms of metallic iron when the total dust is 100% by mass.
(3) heating a mixture containing ascorbic acid powder, FeO powder and water to remove water from the aqueous solution obtained by dissolving the ascorbic acid powder and the FeO powder;
The FeO powder is 50% by mass or more of FeO with respect to the entire FeO powder,
The FeO powder, alkali, characterized by containing the _{CaAl 2 O 4, FeAl 2 O} 4, CaFe 2 Si 2 O 6, at least one mixed oxide of CaSi ₂ O ₅ and MgFe ₂ O ₄ Iron supply agent for soil plants.
(4) The said iron removal agent for plants for alkaline soil as described in said (3) performed at 120 degrees C or less.
(5) The removal is performed at 120 ° C. or lower,
When an aqueous solution obtained by dissolving this alkaline soil for plant for iron supply agent, which contains the ^{Fe 2+} ions and ^{Fe 3+} ions, and the total of the ^{Fe 2+} ions and the ^{Fe 3+} ions is 100 mass%, the Fe ²⁺ ions is 50 to 99 wt%, and the Fe ²⁺ ion concentration of the aqueous solution obtained by dissolving this alkaline soil for plant for iron supply agent, the hydrogen ion exponent measures 7.0 or more areas Then, when the aqueous solution was allowed to stand for 120 hours and the Fe ²⁺ ion concentration was measured again , the concentration after standing was 80% or more of the concentration before standing,
The mixture includes ascorbic acid powder, FeO powder, and water in a mass ratio of 60 to 90: 7 to 28: 3 to 20,
The FeO powder is vacuum-cooled after vacuum heating of a granulated product obtained by granulating iron-containing dust and / or a granulated product obtained by granulating iron-containing dust and metallic iron. FeO powder obtained by
The iron supply agent for plants for alkaline soil according to (3) above, wherein the amount of iron contained in the iron-containing dust is 30% by mass or more in terms of metallic iron when the total amount of dust is 100% by mass.
(6) It consists of a granular material containing ascorbic acid powder and FeO powder in a matrix made of peat,
The FeO powder is 50% by mass or more of FeO with respect to the entire FeO powder,
The FeO powder, alkali, characterized by containing the _{CaAl 2 O 4, FeAl 2 O} 4, CaFe 2 Si 2 O 6, at least one mixed oxide of CaSi ₂ O ₅ and MgFe ₂ O ₄ Iron supply agent for soil plants.
(7) A method for producing an iron supply agent for a plant for alkaline soil according to (1 ) above,
A heating step of heating a mixture containing ascorbic acid powder, FeO powder, and water to obtain an aqueous solution obtained by dissolving the ascorbic acid powder and FeO powder;
The FeO powder is 50% by mass or more of FeO with respect to the entire FeO powder,
The FeO powder, alkali, characterized by containing the _{CaAl 2 O 4, FeAl 2 O} 4, CaFe 2 Si 2 O 6, at least one mixed oxide of CaSi ₂ O ₅ and MgFe ₂ O ₄ The manufacturing method of the iron supply agent for plants for soil.
(8) The mixture includes ascorbic acid powder, FeO powder, and water in a mass ratio of 60 to 90: 7 to 28: 3 to 20,
The FeO powder is vacuum-cooled after vacuum heating of a granulated product obtained by granulating iron-containing dust and / or a granulated product obtained by granulating iron-containing dust and metallic iron. FeO powder obtained by
The amount of iron contained in the iron-containing dust is 30% by mass or more in terms of metallic iron when the entire dust is 100% by mass,
The granulated product has a particle size of 25 mm or less,
The degree of vacuum in the vacuum heating is 0.1 to 13.3 KPa and the heating temperature is 600 to 1100 ° C.,
The degree of vacuum in the vacuum quenching is 5.3 to 13.3 KPa, and the plant iron supply agent for alkaline soil according to (7), which is cooled to a temperature of 300 ° C. or less at a temperature decrease rate of 5 to 150 ° C./min. Production method.
(9) A method for producing a ferrous iron additive for alkaline soil according to (3 ) above,
A dissolution step of heating a mixture containing ascorbic acid powder, FeO powder, and water to obtain an aqueous solution obtained by dissolving the ascorbic acid powder and FeO powder;
A drying step of removing water from the aqueous solution,
The FeO powder is 50% by mass or more of FeO with respect to the entire FeO powder,
The FeO powder, alkali, characterized by containing the _{CaAl 2 O 4, FeAl 2 O} 4, CaFe 2 Si 2 O 6, at least one mixed oxide of CaSi ₂ O ₅ and MgFe ₂ O ₄ The manufacturing method of the iron supply agent for plants for soil.
(10) The said removal is a manufacturing method of the iron supply agent for plants for alkaline soil as described in said (9) performed at 120 degrees C or less.
(11) The removal is performed at 120 ° C. or lower,
The mixture includes ascorbic acid powder, FeO powder, and water in a mass ratio of 60 to 90: 7 to 28: 3 to 20,
The FeO powder is vacuum-cooled after vacuum heating of a granulated product obtained by granulating iron-containing dust and / or a granulated product obtained by granulating iron-containing dust and metallic iron. FeO powder obtained by
The amount of iron contained in the iron-containing dust is 30% by mass or more in terms of metallic iron when the entire dust is 100% by mass,
The granulated product has a particle size of 25 mm or less,
The degree of vacuum in the vacuum heating is 0.1 to 13.3 KPa and the heating temperature is 600 to 1100 ° C.,
The degree of vacuum in the vacuum quenching is 5.3 to 13.3 KPa, and the plant iron supply agent for alkaline soil according to (9) is cooled to a temperature of 300 ° C. or less at a temperature decrease rate of 5 to 150 ° C./min. Production method.

Hereinafter, the present invention will be described in detail.
[1] Plant iron supply agent for alkaline soil The plant iron supply agent for alkaline soil can be composed of an aqueous solution obtained by dissolving ascorbic acid and an iron component.
Further, alkaline soil for plant for iron supply agent may be ascorbic acid, iron components, and which is formed by removing water from the aqueous solution obtained is dissolved. That is, it is obtained isosamples removing water from the alkali soil for plant for iron supply agent.
Further plants for iron supply agent for alkaline soil can be a matrix consisting of peat and / or clay, as the ascorbic acid and iron component consists granules which are contained.
Then, the plant iron supply agent for alkaline soil of the present invention (hereinafter simply referred to as “the plant iron supply agent”) heats a mixture containing ascorbic acid powder, FeO powder, and water, An aqueous solution obtained by dissolving ascorbic acid powder and FeO powder,
The FeO powder is 50% by mass or more of FeO with respect to the entire FeO powder,
The FeO powder is characterized by containing the _{CaAl 2 O 4, FeAl 2 O} 4, CaFe 2 Si 2 O 6, at least one mixed oxide of CaSi ₂ O ₅ and MgFe ₂ O _4.
Another plant iron supply agent for alkaline soil according to the present invention (hereinafter simply referred to as “the other plant iron supply agent”) is obtained by heating a mixture containing ascorbic acid powder, FeO powder, and water. Water is removed from the aqueous solution obtained by dissolving the ascorbic acid powder and the FeO powder,
The FeO powder is 50% by mass or more of FeO with respect to the entire FeO powder,
The FeO powder is characterized by containing the _{CaAl 2 O 4, FeAl 2 O} 4, CaFe 2 Si 2 O 6, at least one mixed oxide of CaSi ₂ O ₅ and MgFe ₂ O _4. That is, the other iron supply agent for plants is obtained by removing water from the iron supply agent for plants.
Still another plant iron supply agent for alkaline soil of the present invention (hereinafter simply referred to as “this further iron supply agent for plants”) contains a peat matrix containing ascorbic acid powder and FeO powder. Made of granular material,
The FeO powder is 50% by mass or more of FeO with respect to the entire FeO powder,
The FeO powder is characterized by containing the _{CaAl 2 O 4, FeAl 2 O} 4, CaFe 2 Si 2 O 6, at least one mixed oxide of CaSi ₂ O ₅ and MgFe ₂ O _4.

The “iron component” is not particularly limited, and may be an iron compound or metallic iron such as iron powder. The iron compound is not particularly limited, but a compound having divalent iron in the molecule is more preferable. Examples of the iron compound include oxides such as FeO, inorganic salts such as FeSO ₄ , Fe (NO ₃ ) ₂ , and FeCl ₂ , organic salts such as trimethoxy iron, and chelate compounds such as Fe-EDTA and Fe-EDDHA. Is mentioned. As this iron compound, FeO is particularly preferable. Only one iron compound may be used, or two or more iron compounds may be used in combination. Furthermore, metallic iron and one or more iron compounds may be used in combination. The iron component is preferably metallic iron and / or FeO, and more preferably FeO.

The “aqueous solution” is an aqueous solution obtained by heating a mixture containing ascorbic acid powder, FeO powder, and water to dissolve the ascorbic acid powder and the FeO powder . That is, it is an aqueous solution not containing ascorbic acid that cannot be completely dissolved and FeO that cannot be completely dissolved. However, this aqueous solution may be a supernatant in a solid-liquid coexisting material containing ascorbic acid that cannot be dissolved and / or FeO that cannot be dissolved.
Moreover, the dissolved state in the aqueous solution of ascorbic acid and FeO is not specifically limited. That is, for example, this aqueous solution can contain an iron ascorbate complex and an ascorbate ion. Among these, it is particularly preferable that an iron ascorbate complex is contained.

How to obtain this solution can be heated with (1) Ascorbic acid powder, and FeO powder, and water, a mixture containing. In addition, (2) FeO powder can be added to an ascorbic acid aqueous solution in which the entire amount has been dissolved in advance and heated. Moreover, (3) Ascorbic acid powder and FeO powder may be further added to an ascorbic acid aqueous solution in which a predetermined amount has been dissolved in advance and heated. Further, (4) it can be obtained by mixing ascorbic acid powder, FeO powder and water without heating. (5) In addition to the above (1) to (4), when an undissolved ascorbic acid and undissolved FeO are contained, a production method comprising a step of separating them by a method such as filtration can do.

(4) Other iron fertilizers for plants using a biodegradable extender as a matrix Iron fertilizers for plants using a biodegradable extender as a matrix include peat and / or biodegradable extenders. Or clay can be contained. These biodegradable extenders are water-repellent, and when the plant iron supply agent is used in alkaline soil, the intrusion into the plant iron supply agent such as an aqueous solution having a high pH from the surroundings is suppressed, and the pH is reduced. Since it keeps low, the fall of the solubility of FeO is suppressed and the oxidation of Fe ^<2+> ion is also suppressed more. Therefore, Fe ²⁺ ions can be supplied stably over a long period of time. That is, excellent sustained release can be imparted by the plant iron supplier.

Further, this other iron supply agent for plants comprises a granular material in which ascorbic acid powder and FeO powder are contained in a matrix made of peat which is a biodegradable extender having water repellency. The shape of the particles constituting the granular body is not particularly limited, and may be any of a sphere, an ellipsoid, a hemisphere, a cube, a cuboid, a cylinder, a briquette, and the like. Further, the granular body may be a dense body or a porous body. Further, the particle diameter (diameter in the case of a sphere, or maximum pass dimension in the case of other shapes) is preferably 50 mm or less (more preferably 10 mm or less, further preferably 6 mm or less, usually 0.5 mm or more).

Furthermore, in this other iron supply agent for plants using a biodegradable extender as a matrix, the total of ascorbic acid, FeO contained as an iron component and peat as a biodegradable extender is 100% by mass. Moreover, it is preferable that 1-30 mass% of ascorbic acid is contained, and 1-30 mass% of FeO is contained. The ascorbic acid content is more preferably 3 to 20% by mass, particularly preferably 7 to 13% by mass, and the FeO content is more preferably 3 to 20% by mass, and particularly preferably 7 to 8% by mass. Thus, reduction in the solubility of FeO is sufficiently suppressed, and be more sufficiently suppressed the oxidation of Fe ²⁺ ions, it can be supplied stably Fe ²⁺ ions over a long period.

[4] Manufacturing method of plant iron supply agent for alkaline soil (1) Manufacturing method of plant iron supply agent for alkaline soil of the present invention The manufacturing method of the present invention comprises ascorbic acid powder, FeO powder, water, And a dissolution step of heating the mixture containing the aqueous solution obtained by dissolving the ascorbic acid powder and the FeO powder .

The “ FeO powder” is a powder containing the FeO as a main component. The amount of FeO contained in this FeO powder is usually 50% by mass or more (preferably 65% by mass or more and may be 100% by mass) of FeO with respect to the entire FeO powder. As this FeO powder, any FeO powder may be used, and a FeO powder described later (a granulated product obtained by granulating dust containing iron (hereinafter also referred to as “dust”), and / or A granulated product obtained by granulating this dust and a reducing agent, FeO powder obtained by vacuum heating and vacuum quenching), and various commercially available FeO powders can be used. Among these, FeO powder obtained by heating the above-mentioned granulated product in a vacuum and then rapidly cooling in a vacuum is preferable.
As the “water”, any water can be used as described above.

The amount of ascorbic acid powder, FeO powder and water charged in the “mixture” is not particularly limited, but ascorbic acid powder (assuming purity 100%): FeO powder (assuming purity 100%): water (purity 100%) (Assuming) it is preferably used in a ratio of 60 to 90: 7 to 28: 3 to 20, more preferably in a ratio of 65 to 85:10 to 24: 5 to 17.5, 68 to It is particularly preferable to use at a ratio of 72:10 to 22:10 to 15.

In addition to ascorbic acid powder, FeO powder and water, the above mixture may or may not contain other components. When it contains another component, it may be contained in a state dissolved in water, or may be contained in a state not dissolved in water. Examples of other components include methanol and ethanol. By containing these, water can be removed more smoothly even under a reduced pressure environment. Only 1 type may contain these and 2 or more types may contain.

The conditions for the “heating” are not particularly limited, but the heating temperature is preferably maintained at 120 ° C. or lower. This is because if it exceeds 120 ° C., the Fe ³⁺ ion concentration tends to increase. The temperature of the aqueous solution by this heating is more preferably 110 ° C. or less, further preferably 105 ° C. or less, and particularly preferably 100 ° C. or less. On the other hand, the lower limit temperature is not particularly limited, and is preferably 40 ° C. or higher, more preferably 50 ° C. or higher, and particularly preferably 60 ° C. or higher. These upper limit temperature and lower limit temperature at the time of heating can be combined. That is, for example, 40 to 120 ° C is preferable, 50 to 110 ° C is more preferable, and 60 to 100 ° C is still more preferable. Combinations other than these may be used. In addition, the pressure conditions in the case of a heating are not specifically limited.
By this heating, more ascorbic acid is dissolved in water, and the amount of FeO dissolved is increased accordingly, and the concentration of the target Fe ²⁺ ion or Fe ²⁺ ion complex is considered to be increased.

In the manufacturing method of this invention, the process of removing a water-insoluble component can be provided after the said melt | dissolution process. Examples of the water-insoluble component include ascorbic acid powder that does not completely dissolve and FeO powder that does not completely dissolve. Although the removal method is not particularly limited, it can usually be performed by filtration. That is, a filtration step can be provided. The filtration conditions at this time are not particularly limited. For example, it is preferable to use a membrane filter having a pore size of 10 μm or less (more preferably 5 μm or less, more preferably 3 μm or less) as the filtration filter.

(2) Method for producing plant iron supplier for alkaline soil using biodegradable extender as matrix The method for producing plant iron supplier using biodegradable extender as matrix is not particularly limited. It can be obtained by mixing and granulating peat and / or clay, which is a biodegradable extender (usually powder or granules), having ascorbic acid and FeO powder.
The mixing method is not particularly limited, and dry blending using a mortar mixer, an omni mixer, or the like may be used, and mixing may be performed using a kneader, a wet pan, or the like. Further, the granulation method is not particularly limited, but it is usually granulated by an extrusion method. Further, it is preferable that the mixing and granulation are continuously performed by extrusion molding because the process can be simplified. The temperature for the dry blending and extrusion molding is not particularly limited, and may be room temperature (for example, 15 to 35 ° C.) or may be heated to about 40 to 90 ° C. as necessary.
About ascorbic acid powder and FeO powder, each description in the manufacturing method of the iron supply agent for plants of the said (1) this invention is applicable as it is. However, when the total of peat and / or clay, ascorbic acid powder and FeO powder is 100% by mass, 1 to 30% by mass of ascorbic acid powder and 1 to 30% by mass of FeO powder are blended.
Still another plant iron supplier can be obtained by mixing and granulating peat and / or clay and the other plant iron supplier. The mixing and granulation at this time can be performed in the same manner as described above.
Moreover, when using the said other iron supply agent for plants, the mass ratio of peat and / or clay, ascorbic acid powder, and FeO powder is the same as the above, and this mass ratio is for other plants. It can adjust with the mass ratio of each ascorbic acid powder and FeO powder used when manufacturing an iron supply agent, and the mass ratio of peat and / or clay, and this other iron supply agent for plants.

The FeO powder, in addition to FeO, containing _{CaAl 2 O 4, FeAl 2 O} 4, CaFe 2 Si 2 O 6, at least one mixed oxide of CaSi ₂ O ₅ and MgFe ₂ O _4. These double oxides may contain only 1 type and 2 or more types may contain them. Moreover, 0.5-10 mass% is preferable when content of double oxide makes the whole FeO powder 100 mass%. If it is this range, the iron supply agent excellent in antioxidant property can be obtained.
Furthermore, the particle diameter of the particles constituting the FeO powder is not particularly limited, but may be any FeO powder having a particle diameter of 5000 μm or less and mixed with powders having various particle diameters. Furthermore, porous particles may be included.

Experimental Example 8: 1 g of fertilizer (manufactured by Chisso Asahi Fertilizer Co., Ltd., trade name “Long Total 70”) was blended with the fossil shell fossil soil in the pot to prepare a seedling culture soil.
Experimental Example 9: In the shell fossil soil in the pot, 1 g of the fertilizer and the iron fertilizer for plants for alkaline soil (A) (in Table 1, “A” in the column of type and “granule” in the column of property). The same applies hereinafter.) 0.1 g was blended to prepare a seedling culture soil.
Experimental Example 10: 1 g of the above fertilizer and the above-mentioned ferrous fertilizer for plants for alkaline soil (B) (in Table 1, “B” in the column of type and “powder” in the property column). The same applies hereinafter.) 0.1 g was blended to prepare a seedling culture soil.
Experimental Example 11: 1 g of the above fertilizer and 1.0 g of the above-mentioned fertilizer for plant for alkaline soil (A) were blended in the shell fossil soil in the pot to obtain a seedling culture soil.
Experimental Example 12: 1 g of the above fertilizer and 1.0 g of the above-mentioned fertilizer for plants for alkaline soil (B) were blended with the fossil shell soil in the pot to obtain a seedling culture soil.
Experimental Example 13: 1 g of the above fertilizer and 2.0 g of the above-mentioned fertilizer for plants for alkaline soil (A) were blended with the fossil shell soil in the pot to obtain a seedling culture soil.
Experimental Example 14: 1 g of the above fertilizer and 2.0 g of the above-mentioned fertilizer for plant for alkaline soil (B) were blended with the fossil shell fossil soil in the pot to obtain a seedling culture soil.
Experimental Example 15: 1 g of the above fertilizer and the above-mentioned ferrous fertilizer for plants for alkaline soil (C) (referred to as “C” in the column of type and “powder” in the column of property in Table 1). The same applies hereinafter.) 0.1 g was blended to prepare a seedling culture soil.
Experimental Example 16: 1 g of the above fertilizer and 1.0 g of the above-mentioned fertilizer for plants for alkaline soil (C) were blended with the fossil shell soil in the pot to obtain a seedling culture soil.

In addition, for example, a mixture obtained by mixing ascorbic acid powder and FeO powder, adding a small amount of water to the mixture, and then removing the water can be used as an iron supply agent for plants for alkaline soil. . In this case, the amount of water relative to the ascorbic acid powder is not particularly limited, but usually the water is 5 to 20 parts by mass, more preferably 5 to 15 parts by mass with respect to 100 parts by mass of the ascorbic acid powder. On the other hand, the FeO powder can be blended in an amount of 10 to 25 parts by mass, particularly 20 to 25 parts by mass when the ascorbic acid powder is 100 parts by mass.
About said ascorbic acid powder and FeO powder, the said description is applicable as it is. Moreover, the moisture content in the solid substance or paste-like substance obtained by using a small amount of water as described above can be set to the same level as the other iron supply agents for plants. Further, the water removal method can be the same as that for the other iron supply agent for plants, and drying under reduced pressure is preferable. Moreover, the temperature at the time of heating when removing water and the pressure at the time of reducing the pressure when removing water can be the same as those of the other iron supply agents for plants.

Claims (26)

A plant iron supply for alkaline soil, comprising an aqueous solution obtained by dissolving ascorbic acid and an iron component. The plant iron supply agent for alkaline soil according to claim 1, wherein the iron component is metallic iron and / or FeO. The iron supplier for plant for alkaline soil according to claim 2, wherein the iron component is FeO. A said iron component is FeO, and contains a ^{Fe 2+} ions and ^{Fe 3+} ions, in the case where the total of the ^{Fe 2+} ions and the ^{Fe 3+} ions is 100 mass%, the ^{Fe 2+} ions 50 to 99 mass The plant iron supply agent for alkaline soil according to claim 1, which is%. The iron component was FeO, and the Fe ²⁺ ion concentration of the aqueous solution was measured in a region where the hydrogen ion index was 7.0 or more, and then the aqueous solution was allowed to stand for 120 hours, and the Fe ²⁺ ion concentration was measured again. In the case, the iron supply agent for plants for alkaline soil according to claim 1, wherein the concentration after standing is 80% or more of the concentration before standing. The plant iron supply for alkaline soil according to claim 1, comprising a biodegradable binder. The plant iron supply agent for alkaline soil according to claim 1, comprising a biodegradable extender. An iron supply agent for alkaline soil plants, wherein water is removed from an aqueous solution obtained by dissolving ascorbic acid and an iron component. The iron supplier for plant for alkaline soil according to claim 8, wherein the iron component is metallic iron and / or FeO. The iron supplier for plants for alkaline soil according to claim 9, wherein the iron component is FeO. A said iron component is FeO, aqueous solution obtained by dissolving this alkaline soil for plant for iron supply agent containing the ^{Fe 2+} ions and ^{Fe 3+} ions, the sum of the ^{Fe 2+} ions and the ^{Fe 3+} ions 100 The iron supplier for an alkaline soil plant according to claim 8, wherein the Fe ²⁺ ion is 50 to 99% by mass when the mass is% by mass. The iron component is FeO, and the Fe ²⁺ ion concentration of an aqueous solution obtained by dissolving the plant iron supply agent for alkaline soil is measured in a region where the hydrogen ion index is 7.0 or more. The plant iron supply for alkaline soil according to claim 8, wherein the concentration after standing is 80% or more of the concentration before standing when the Fe ²⁺ ion concentration is measured again after standing for a period of time. The plant iron supply for alkaline soil according to claim 8, comprising a biodegradable binder. The plant iron supply agent for alkaline soil according to claim 8, which contains a biodegradable extender. An iron supply agent for plants for alkaline soil, characterized in that it comprises a granular material containing ascorbic acid and an iron component in a matrix composed of peat and / or clay. When the total of the peat and / or clay, the ascorbic acid and the FeO contained as the iron component is 100% by mass, the ascorbic acid is 1 to 30% by mass, and the FeO is 1 to 30% by mass. The plant iron supply agent for alkaline soil according to claim 15. It comprises a dissolution step of heating a mixture containing ascorbic acid powder, iron component powder, and water to obtain an aqueous solution obtained by dissolving the ascorbic acid powder and the iron component powder. The manufacturing method of the iron supply agent for plants for alkaline soils. The said iron component powder is an iron powder and / or FeO powder, The manufacturing method of the iron supply agent for plants for alkaline soil of Claim 17. The method for producing an iron supplier for an alkaline soil plant according to claim 18, wherein the iron component powder is FeO powder. The manufacturing method of the iron supply agent for plants for alkaline soil of Claim 17 provided with the drying process which removes water from the said aqueous solution. The FeO powder is vacuum-cooled after a vacuum heating of a granulated product obtained by granulating iron-containing dust and / or a granulated product obtained by granulating iron-containing dust and a reducing agent. The method for producing an iron supply agent for an alkaline soil plant according to claim 19, wherein the FeO powder is obtained by FeO powder. It is a manufacturing method of the iron supply agent for plants for alkaline soil according to claim 15,
A method for producing an iron supply agent for a plant for alkaline soil, characterized in that the peat and / or clay, ascorbic acid powder, and iron component powder are mixed and then granulated. The method for producing an iron supplier for an alkaline soil plant according to claim 22, wherein the iron component powder is iron powder and / or FeO powder. The method for producing an iron supplier for an alkaline soil plant according to claim 23, wherein the iron component powder is FeO powder. When the total of the peat and / or clay, the ascorbic acid powder and the FeO powder is 100% by mass, the ascorbic acid powder is 1 to 30% by mass, and the FeO powder is 1 to 30% by mass. The manufacturing method of the iron supply agent for plants for alkaline soils of Claim 24. The FeO powder is vacuum-cooled after a vacuum heating of a granulated product obtained by granulating iron-containing dust and / or a granulated product obtained by granulating iron-containing dust and a reducing agent. The method for producing an iron supply agent for a plant for alkaline soil according to claim 24, wherein the FeO powder is obtained by the above process.