JP2022064141A - Culture soil for paddy rice cultivation, and paddy rice cultivation method using the same - Google Patents

Abstract

To provide culture soil for paddy rice cultivation which does not drastically reduce taste (preferably can maintain taste) while improving yield of rice, and a paddy rice cultivation method capable of easily cultivating paddy rice in which taste is not drastically reduced while yield of rice is improved without requiring any special water-level adjustment or the like.SOLUTION: Culture soil for paddy rice cultivation includes porous bodies having sedimentation property. Further, the porous bodies of the culture soil for paddy rice cultivation have 0.4 or more of specific gravity. A paddy rice cultivation method includes cultivating of paddy rice by using the culture soil for paddy rice cultivation.SELECTED DRAWING: None

Description

The present invention relates to hilling soil for paddy rice cultivation and a paddy rice cultivation method using the same, and more particularly to a hilling soil for paddy rice cultivation containing a specific porous body and a paddy rice cultivation method using the same.

The development of mechanized technology in paddy rice cultivation has contributed to the reduction of direct working hours of farmers, the cost reduction of rice cultivation, and the increase of yield. However, in recent years, the increase in yield has stagnated. One reason for this is thought to be the decline (simplification) of paddy field management labor due to the aging of farmers. Originally, by applying the original fertilizer with livestock manure compost after harvesting paddy rice, the soil fertility (the ability to grow the plants of the land) is restored, and the yield is expected to increase in the next fiscal year. However, in recent years, agricultural workers have been aging, and livestock manure compost, which is heavy and cumbersome to handle, has been avoided, and the amount of compost used in paddy fields has decreased to about one-fourth in 30 years. Therefore, it is said that the number of soils with reduced soil fertility or poor nutritional balance is increasing, and the increase in yield per unit area of paddy rice is slowing down.

In general, it has been pointed out that the high use of nitrogen fertilizers (eg, compost and chemical fertilizers) to increase yields increases the protein content in brown rice. It is known that when the protein content in brown rice is high, the taste of rice is deteriorated.

Therefore, silicon (Si) -containing fertilizers are attracting attention in order to increase the yield. It is known that the higher the silicon content in the foliage, the more the rice leaves stand upright and the better the light receiving condition. Furthermore, when the development of stem and leaf cells is promoted during the growth of rice, the tissue becomes stronger, which can be expected to reduce damage caused by pests and collapse. Further, since the oxidizing power of the root is improved, there are advantages such as prevention of root rot.
However, since it is said that the amount of silicon absorbed by paddy rice reaches about 10 times that of nitrogen and about 20 times that of phosphoric acid, in reality, the silicon deficiency in soils with reduced soil fertility, which has been increasing in recent years, is serious. Since it is said that the amount of silicic acid required to produce 100 kg of brown rice is about 20 kg, the use of silicon-containing fertilizer is considered indispensable.

Patent Document 1 discloses a paddy rice cultivation method in which an aqueous solution containing potassium silicate is brought into contact with at least a part of paddy rice, and when the paddy rice cultivation method is used, the yield of rice is improved while maintaining the taste. It is shown that this can be done (see Claim 1, [0004] to [0006], [0016] to [0017] of Patent Document 1).

Patent Document 2 discloses paddy rice seedling hilling containing a vitreous foam and at least one other material, and the paddy rice seedling hilling has an appropriate weight (about 40% of granulated hilling of the same capacity). It is shown that it is easy to carry, is hard to be washed away, is suitable for sowing work by a sowing machine, enables sound seedling raising, and contributes to environmental conservation because it uses recycled materials derived from glass (Patent Document 2 Summary, Claims). 1. See [0009], [0013], [0058], etc.).

Japanese Unexamined Patent Publication No. 2014-212703 Japanese Unexamined Patent Publication No. 2012-165657

Patent Document 1 discloses that the yield is improved while maintaining the taste of rice by using an aqueous solution containing potassium silicate, but the water level adjustment of the paddy field in the paddy field cultivation method is complicated. .. For example, it is necessary to lower the water level of the paddy field so that the ground is exposed, and then supply an aqueous solution containing potassium silicate to the paddy field about two weeks later (Patent Document 1, Claim 3, [0013], [ 0015] to [0016]).

Patent Document 2 discloses that if paddy rice seedling cultivation soil containing a vitreous foam is used, it is possible to easily carry the seedlings, to grow healthy seedlings, and to contribute to environmental conservation. It does not disclose or teach the yield and taste of the rice that is planted in the rice planting and cultivated in paddy rice. The inventors of the present application used the vitreous foam used in the examples of Patent Document 2 (a glass foam corresponding to the description in JP-A-11-236232, which has substantially only independent foam). When I raised the seedlings and planted them in the paddy field, I noticed that the paddy rice seedling cultivation soil that had been transferred to the paddy field together with the seedlings did not settle in the water and flowed out of the paddy field together with the outflow of water. Therefore, it is clear that the paddy rice seedling cultivation soil described in Patent Document 2 can be used for the seedling raising period, but cannot be used for paddy rice cultivation in paddy fields.

Therefore, while improving the yield of rice, the soil for paddy rice cultivation that does not significantly reduce the taste (preferably the taste can be maintained, preferably the taste can be improved), and any special cultivation method (for example, specific water level adjustment, etc.) ) Is required, and there is a demand for a paddy rice cultivation method that improves the yield of rice and does not significantly reduce the taste (preferably the taste can be maintained, preferably the taste can be improved).

As a result of diligent studies, the present inventors grow seedlings using paddy rice cultivation soil containing a specific porous body, and the seedlings are used as paddy fields with the paddy rice cultivation soil attached to the roots of the seedlings. It was found that when planted, it increased the yield of rice but did not significantly reduce the taste. Furthermore, the present invention was completed by finding that the soil for paddy rice cultivation does not flow out in the paddy field and that special water level adjustment or the like is not required during the paddy field cultivation period.

The present specification includes the following embodiments.
1. 1. Cultivated soil for paddy rice cultivation, including a porous body with sedimentation.
2. 2. The soil for paddy rice cultivation according to 1 above, wherein the porous body has a specific density of 0.4 or more.
3. 3. The soil for paddy rice cultivation according to 1 or 2 above, wherein the porous body contains an inorganic substance.
4. The soil for paddy rice cultivation according to any one of 1 to 3 above, wherein the porous body contains a foam containing silicon dioxide as a main component.
5. The soil for paddy rice cultivation according to 4 above, wherein the foam contains foam glass.
6. The soil for paddy rice cultivation according to any one of 1 to 5 above, wherein the size of the porous body is 30 mm or less.
7. The soil for paddy rice cultivation according to any one of 1 to 6 above, wherein the porous body has pores of 0.1 to 1000 μm.
The soil for paddy rice cultivation according to any one of 1 to 7 above, which comprises 8.5 to 30% by volume of a porous body.
9. A method for cultivating paddy rice, which comprises cultivating paddy rice in a paddy field using the soil for paddy rice cultivation according to any one of 1 to 8 above.
10. The paddy rice cultivation method according to 9 above, which comprises cultivating paddy rice by entwining the cultivation soil for paddy rice with the roots of the paddy rice.
11. Growing paddy rice seedlings using paddy rice hilling;
Planting seedlings in paddy fields with soil for paddy rice cultivation;
9. The method for cultivating paddy rice according to 9 or 10 above, which comprises growing seedlings in a paddy field and cultivating paddy rice.
12. The paddy rice cultivation method according to 11 above, which comprises sowing paddy on hilling for paddy rice cultivation and growing paddy rice seedlings.
13. The paddy rice cultivation method according to 11 or 12 above, which comprises growing paddy rice seedlings using paddy rice cultivation soil and entwining the roots of the seedlings with the paddy rice cultivation soil.
14. The paddy rice cultivation method according to any one of 11 to 13 above, which comprises planting seedlings in a paddy field together with soil for paddy rice cultivation using a rice transplanter.

When the soil for paddy rice cultivation according to the embodiment of the present invention is used, the yield of rice is improved and the taste is not significantly deteriorated (preferably the taste can be maintained, more preferably the taste can be improved). Furthermore, when the paddy rice cultivation method of the embodiment of the present invention is used, the yield of rice is improved and the taste is not significantly deteriorated without requiring any special cultivation method (for example, water level adjustment) (for example, water level adjustment). Paddy rice can be cultivated, preferably maintaining the taste and more preferably improving the taste).

In one embodiment of the present invention, there is provided a soil for paddy rice cultivation, which comprises a porous body having a sedimentation property.
In the present specification, "cultivated soil for paddy rice cultivation" refers to soil (or potting soil) for cultivating paddy rice, and is not particularly limited as long as paddy rice can be cultivated. The paddy hilling soil can be used not only for raising seedlings of paddy rice in the nursery, but also for cultivating paddy rice in the paddy field. The hilling for paddy rice cultivation can be used for the entire paddy field, but it is preferable to selectively use it in the part of the paddy field where the seedlings of paddy field are planted.

In the present specification, "paddy rice" means rice cultivated in a paddy field, and more specifically, for example, rice cultivated in a paddy field filled with water. In the present specification, the rice is generally referred to as paddy rice and is cultivated in a paddy field, and the paddy rice is not particularly limited as long as the hilling soil for paddy rice cultivation according to the embodiment of the present invention can be used.

Such "rice" includes two subspecies, the Japanese type (subsp. Japonica Kato) and the Indian type (subsp. Indica Kato). The Japanese type is cultivated in relatively high latitude areas such as Japan, the Korean Peninsula, Taiwan, and northern China, as well as Brazil and California in the United States. The rice grains are round and short, and are sticky when cooked. The Indian type is usually called indica rice, Thai rice, Nankinmai, etc. in Japan, mainly in low latitude areas such as Southeast Asia, Africa, the southern part of the United States, and the Mediterranean coast represented by the Lombardia region of Italy. Cultivated.
Rice includes various varieties, such as Koshihikari, Hitomebore, Hinohikari, Akitakomachi, Nanatsuboshi, Haenuki, Kinuhikari, Masigura, Asahi no Yume, Yumepirika and the like. As long as the paddy rice cultivation soil of the embodiment of the present invention can be used, the rice varieties are not particularly limited.

In the present specification, the "paddy field" refers to a cultivated land in which a ridge is formed around the paddy field to allow water to be filled, and the paddy field cultivation soil according to the embodiment of the present invention is used. As long as paddy rice can be cultivated, there are no particular restrictions.

In the embodiment of the present invention, the porous body (also referred to as a porous material) is a material having many pores, and is an organic substance that can hold and / or permeate water and can be a fertilizer. And / or an inorganic substance can be retained, and the soil for paddy rice cultivation, which is the object of the present invention, is not particularly limited as long as it can be obtained.

In the embodiment of the present invention, it is preferable that the porous body has a sedimentation property.
As for the sedimentation property of the porous body, as described in Examples, 100 mL of the porous body is placed in 1 L of distilled water, and after 24 hours, the porous body floats or sinks in the distilled water. It can be evaluated by visually observing whether or not it is present.
When 50% or more of the porous body is submerged in distilled water after 24 hours, it is considered to have sedimentation property. In this case, by using the soil for paddy rice cultivation according to the embodiment of the present invention, it is advantageous that the yield of rice is improved and the taste is not significantly deteriorated (preferably the taste can be maintained, more preferably the taste can be improved). Has a great effect.

The specific gravity of the porous body is preferably 0.4 or more, more preferably 0.6 to 1.2, still more preferably 0.6 to 1.1, and 0.7 to 0.7. It is particularly preferably 1.0.
The specific gravity can be measured according to the method described in JIS Z8807.
By using the soil for paddy rice cultivation in which the specific gravity of the porous body is 0.4 or more, the yield of rice is improved and the taste is not significantly deteriorated (preferably the taste can be maintained, more preferably the taste is improved). It can have the advantageous effect of being able to.

In the embodiment of the present invention, the porous body preferably has water permeability.
The permeability of the porous body is evaluated by measuring the time required for 200 mL of distilled water to pass through a rectangular parallelepiped massive porous body of about 5 × about 5 × about 5 cm, as described in Examples. Can be done. If at least one portion of 200 mL of distilled water passes through the foam glass within 24 hours, it is considered to be water permeable. In this case, by using the soil for paddy rice cultivation according to the embodiment of the present invention, it is advantageous that the yield of rice is improved and the taste is not significantly deteriorated (preferably the taste can be maintained, more preferably the taste can be improved). Has a great effect.

Examples of the porous body include inorganic substances such as diatomite, zeolite, pumice stone, rubble, silica gel, and foamed glass. The porous body preferably contains an inorganic substance. When the porous body contains an inorganic substance, the porous body can maintain its morphology for one year, and the porous body can exert its effect for one year.

The porous body preferably contains a foam containing silicon dioxide as a main component (for example, foamed stone, foamed glass, etc.), and more preferably contains foamed glass. When the porous body contains a foam containing silicon dioxide as a main component, since silicon dioxide has substantially the same component as soil, there is little risk of returning to the soil and unnecessarily contaminating the soil.

The size of the porous body is, for example, 30 mm or less, for example, 25 mm or less, for example, 20 mm or less, for example, 15 mm or less, for example, 10 mm or less, for example, 7 mm or less. The size of the porous body is, for example, 30 mm or less, for example, 25 mm or less, for example, 20 mm or less, for example, 0.5 mm or more, for example, 1 mm or more, for example, 2 mm or more. It is 3 mm or more. The size of the porous body is indicated by whether or not the sieve can pass through a sieve having an opening of X mm.

The pore diameter of the porous body is, for example, 0.1 to 1000 μm, preferably 0.3 to 500 μm, more preferably 0.6 to 100 μm, and particularly preferably 1 to 50 μm. ..

In the embodiment of the present invention, the foamed glass means a glass having a large number of pores, and in one example, it can be produced by firing a mixture of crushed glass and a foaming agent. The method for producing foam glass will be described in detail.

First, glass that is a raw material for foam glass (hereinafter referred to as "raw material glass") is crushed. The type of raw material glass is not particularly limited as long as the soil for paddy rice cultivation according to the embodiment of the present invention can be obtained, and examples thereof include soda-lime glass, borosilicate glass, and aluminosilicate glass. As the raw material glass, waste glass derived from a cathode ray tube, a liquid crystal display, a plasma display, or the like may be used. The method for crushing the raw material glass is not particularly limited, and the raw glass can be crushed using a commercially available vibration mill or the like. The particle size of the pulverized glass (hereinafter referred to as “crushed glass”) is not particularly limited, but it is preferably small so that the pulverized glass and the foaming agent described later are uniformly mixed. In one example, it is preferable to perform particle size selection using a sieve having an opening of 500 μm or less after pulverizing the raw material glass so that the particle size of the pulverized glass is 500 μm or less.
In the present specification, "the particle size is X μm or less" means that the sieve passes through a sieve having an opening of X μm.

Next, the pulverized glass and the foaming agent are mixed. The type of foaming agent is not particularly limited as long as the soil for paddy rice cultivation according to the embodiment of the present invention can be obtained, but for example, a material containing Si 3N _{4 , CaCO 3, and CaCO 3 ( for} example, a shell) is used. be able to. Such a foaming agent generates gas at a temperature at which the glass softens, and as a result, a large number of pores are formed inside the glass to produce foamed glass. The content of the foaming agent is not particularly limited, but is preferably 0.1 to 5% by mass, and particularly preferably 0.2 to 2.0% by mass. When the content is as described above, foaming occurs more sufficiently, and foamed glass having higher strength can be obtained, which is preferable.
The foaming agent preferably contains calcium carbonate (preferably as a main component).
The foaming agent preferably contains shells (preferably as the main component).

Next, the mixture of crushed glass and foaming agent is fired. As long as the soil for paddy rice cultivation according to the embodiment of the present invention can be obtained, the firing temperature and firing time are not particularly limited, and are appropriately set according to the type of glass or foaming agent so that the glass foams appropriately. can do. The firing temperature is, for example, 600 to 1150 ° C. Further, for example, it is 700 to 1100 ° C. The firing temperature is preferably 800 to 1000 ° C. for soda-lime glass. At such a firing temperature, the glass is softened more sufficiently to form pores more appropriately, and a more preferable foamed glass can be produced. The firing time is 1 to 60 minutes in one example, 3 to 25 minutes in one example, and preferably 5 to 20 minutes. With such a firing time, foaming occurs more sufficiently, and a more preferable foamed glass can be produced.

The produced foam glass may be used as a lump, or may be crushed. The particle size of the foamed glass after pulverization is not particularly limited, but is, for example, 30 mm or less, for example, 25 mm or less, for example, 20 mm or less, for example, 15 mm or less, for example, 10 mm or less. For example, it is 7 mm or less.

The soil for paddy rice cultivation according to the embodiment of the present invention preferably contains 2 to 30% by volume of a porous body, more preferably 5 to 28% by volume of a porous body, and more preferably 8 to 25% by volume of a porous body. It is even more preferable to contain a porous body, and it is particularly preferable to contain a porous body of 10 to 23% by volume.
When the soil for paddy rice cultivation according to the embodiment of the present invention contains 2 to 30% by volume of a porous body, the soil for paddy rice cultivation according to the embodiment of the present invention has less outflow due to water and is mixed with the soil. Has the advantageous effect of being able to make it smaller.

The hilling for paddy rice cultivation according to the embodiment of the present invention can generally include materials contained in the hilling for paddy rice cultivation. Examples of such materials include soil (red soil, clayey soil (rice field), humus soil, etc.), compost (taihi), organic substances, fertilizer, and the like, and the soil for paddy rice cultivation according to the embodiment of the present invention can be exemplified. As long as it can be obtained, there are no particular restrictions.
As the hilling soil for paddy rice cultivation according to the embodiment of the present invention, for example, commercially available hilling soil can be used. https://www.yaki-akatsuchi.com/product_category/farmers-items/), Matsusaka Kosan Co., Ltd. Seedling cultivation soil sunbide and lightweight sunbide (https://www.matsusaka-kosan.co.jp/agriculture/index) .php) etc. can be exemplified.

The present invention can provide a paddy rice cultivation method including cultivating paddy rice in a paddy field using the paddy rice cultivation soil according to the embodiment of the present invention.
As long as the paddy field cultivation soil of the embodiment of the present invention can be used and paddy rice is cultivated in a paddy field, the paddy rice cultivation method is not particularly limited.
The paddy rice cultivation method of the embodiment of the present invention can be carried out by using a usual paddy rice cultivation method other than using the paddy rice cultivation soil of the embodiment of the present invention without requiring a special step. It does not require any special cultivation method (for example, water level adjustment), improves the yield of rice, and does not significantly reduce the taste (preferably the taste is maintained, and more preferably the taste is improved). , Paddy rice can be cultivated.

The method for cultivating paddy rice according to the embodiment of the present invention preferably includes cultivating paddy rice by entwining the soil for cultivation for paddy rice with the roots of the paddy rice. By entwining the paddy rice cultivation soil with the paddy rice root, the paddy rice root and the paddy rice cultivation soil come into closer contact, and the paddy rice is a useful material such as water and fertilizer held by the paddy rice cultivation soil. Cultivating paddy rice that can absorb ingredients more efficiently, improve the yield of rice, and do not significantly reduce the taste (preferably maintain the taste, more preferably improve the taste). Can be done.

The paddy rice cultivation method of the embodiment of the present invention
Growing paddy rice seedlings using paddy rice hilling;
Planting seedlings in paddy fields with soil for paddy rice cultivation;
It is preferable to include growing seedlings in paddy fields and cultivating paddy rice.
Since the paddy rice seedlings are grown using the paddy rice cultivation soil of the embodiment of the present invention and the seedlings are planted in the paddy field together with the paddy rice cultivation soil, the paddy rice cultivation soil is used from the time of cultivating the seedlings. It can be cultivated for a long period of time, and even after being planted in paddy fields, the paddy rice can continue to be used effectively with the water, fertilizer, etc. held by the soil for paddy rice cultivation, improving the yield of rice. However, paddy rice can be cultivated without significantly reducing the taste (preferably maintaining the taste and more preferably improving the taste).

In the paddy rice cultivation method of the embodiment of the present invention, it is preferable to include paddy on the paddy rice cultivation soil to grow paddy rice seedlings. Since paddy is sown on the paddy rice cultivation soil to grow paddy rice seedlings, the paddy rice is cultivated using the paddy rice cultivation soil from the time of germination, so that it can be cultivated using the paddy rice cultivation soil for a longer period of time. Therefore, paddy rice can be cultivated without significantly reducing the taste (preferably maintaining the taste and more preferably improving the taste) while improving the yield of rice.

In the paddy rice cultivation method of the embodiment of the present invention, it is preferable to include growing paddy rice seedlings using the paddy rice cultivation soil and entwining the roots of the seedlings with the paddy rice cultivation soil. By growing paddy rice seedlings, the roots of the seedlings are entwined with the soil for paddy rice cultivation, so the roots with water and the soil for paddy rice cultivation are entwined in a natural and natural manner, making it more reasonably and more efficiently for cultivation of paddy rice. The retained water, fertilizer, etc. are absorbed by the paddy rice to cultivate the paddy rice without significantly reducing the taste (preferably maintaining the taste and more preferably improving the taste) while improving the yield of rice. be able to.

In the paddy field cultivation method of the embodiment of the present invention, it is preferable to include planting seedlings in the paddy field together with the soil for paddy rice cultivation using a rice transplanter. In the embodiment of the present invention, the seedlings grown using the paddy rice cultivation soil can be planted in the paddy field by using a rice transplanter, and at that time, the seedlings are planted in the paddy field together with the paddy rice cultivation soil. It is preferable to include. Even in the case of rice planting that requires manpower, the paddy rice cultivation method of the present invention can save labor by using a rice transplanter and does not require any special work. Furthermore, by planting seedlings in paddy fields together with paddy field cultivation soil, it is possible to reduce the risk of damaging the roots of the seedlings entwined with the paddy rice cultivation soil. Since it can be automatically placed within the reach of rice paddies, the soil for paddy rice cultivation can be effectively used in paddy fields.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but these Examples are merely one aspect of the present invention, and the present invention is not limited to these examples.

The materials used in this example, the paddy rice cultivation method, etc. are shown below.
Hinohikari was used as a cultivar.
As the soil for paddy rice, JA Mii's exclusive soil (soil for firing black soil) was used.
Each of the following foam glasses 1 to 5 as a porous body was mixed with the paddy rice hilling at a ratio of 10% by volume or 30% by volume to prepare the paddy rice cultivation soil of Examples 1 to 10. Foam glass 6 was prepared for comparison.
JA Mii's exclusive soil (black soil firing soil) itself was prepared as the soil for paddy rice cultivation in Comparative Example 1.
The seeds (paddy) were soaked in hot water at 60 ° C. for about 10 minutes to disinfect them.
The foamed glass 1 to 6 are shown in Table 1 below, which contains 0.28 g of nitrogen, 0.28 g of phosphoric acid, and 0.28 g of potassium per 1 kg of JA mii-dedicated hilling.

Production of Foam Glass Specifically, the production of foam glass 1 to 6 was carried out as follows.
The foam glass 1 will be described. First, soda-lime glass was crushed so that the particle size was 0.5 mm or less. 1.2% by weight of the foaming agent CaCO3 was added and mixed well. The mixture was fired at a temperature of 900 ° C. for 8 minutes to obtain foamed glass. This foamed glass was pulverized so that the particle size was 1 mm or less to obtain foamed glass 1.
Foamed glasses 2 to 6 were manufactured using the same method as that for foamed glass 1, except that the foaming agents and firing conditions shown in Table 1 were changed.

Relative Density The Relative Density was measured according to the method described in JIS Z8807.

100 mL each of the precipitating foamed glass 1 to 6 was added to a container containing 1 L of distilled water and allowed to stand for 24 hours, and the state of the foamed glass in water was observed.
Most of the foamed glasses 3 and 5 settled on the bottom surface of the container immediately after being added to the distilled water, and most of them remained settled even after 24 hours.
As for the foam glass 6, the majority floated on the surface of the water immediately after being added to the distilled water, and even after 24 hours, the majority remained floating on the surface of the water.
The evaluation criteria for sedimentation are as follows.
Excellent: After 24 hours, 90% or more of the foamed glass particles have settled on the bottom surface of the container.
Possible: After 24 hours, 50% or more of the foamed glass particles have settled on the bottom surface of the container.
Impossible: After 24 hours, 50% or more of the foamed glass particles did not settle on the bottom surface of the container.

The lumpy foamed glass before pulverization for obtaining the water-permeable foamed glass 1 to 6 was shaped into an approximately rectangular parallelepiped of about 5 × about 5 × about 5 cm. The lumpy foamed glass for obtaining the foamed glass 1 to 3 was almost the same, and the lumpy foamed glass (3) for obtaining the foamed glass 3 was investigated as a representative. The lumpy foamed glass for obtaining the foamed glass 4 to 5 was almost the same, and the lumpy foamed glass (5) for obtaining the foamed glass 5 was investigated as a representative. As for the foamed glass 6, a lumpy foamed glass (6) for obtaining the foamed glass 6 was examined.
On the other hand, we prepared a commercially available funnel with legs attached to an inverted square cone-shaped body that can accommodate those shaped lump foam glasses. The shaped lump foam glass was placed in the main body portion of the funnel, and the gaps between the four sides of the lump foam glass and the funnel main body were sealed with a silicon filler. The upper and lower surfaces of the lump foam glass were not sealed with a silicon filler. Allowed to stand for about 2 days to allow the silicone filler to dry completely. The funnel was filled with 200 mL of distilled water, and the presence or absence of water permeation from the lower part of the funnel was visually observed.
In the lump foam glass (5), water permeability was immediately observed from the central portion of the lump foam glass (5). 200 mL of distilled water almost passed through in 24 hours. No water permeability was observed between the funnel and the silicone filler.
On the other hand, in the lump-shaped foamed glass (3) and (6), no water permeability could be observed even after 24 hours had passed.
The evaluation criteria for water permeability are as follows.
Yu: After 24 hours, all the water passed through the lump foam glass.
Possible: After 24 hours, some water passed through the lump foam glass.
No: After 24 hours, no water passed through the lump foam glass.

Table 2 below shows the hilling for paddy rice cultivation of Examples 1 to 10 and the hilling for paddy rice cultivation of Comparative Example 1. The mixing ratio of the foamed glass and the JA Mii exclusive soil is% by volume. Since the foamed glass 6 does not have sedimentation property, it floats on water and flows out, and it is clear that it cannot be used in paddy rice cultivation soil. Therefore, it was not investigated as paddy rice cultivation soil. ..

Paddy rice cultivation method The paddy rice cultivation method used in the present specification is shown below. The method is similar to the paddy rice cultivation method generally used in Japan.
A nursery box (capacity: 4 L, width 580 mm × length 280 mm × height 30 mm, 96 holes having a diameter of 2.45 mm is provided on the bottom surface) was prepared. Using a sowing machine (seed sowing machine), the soil for paddy rice cultivation of Examples 1 to 10 and Comparative Example 1 was planted in a nursery box after bed soil (after being spread in the nursery box) and then with paddy (Hinohikari). Furthermore, it was covered with soil for paddy rice cultivation (covering the paddy). Seeds were sown, for example, in late May. More specifically, it was held on May 17th or 20th.
During the seedling raising period, irrigation was performed twice a day (water was poured).
After confirming the germination of seeds, the seedling raising box was covered with a lawn cloth to prevent sunburn.
The seedlings were raised for about one month from sowing, more specifically, for 35 days or 32 days. The properties of the obtained seedlings are shown in Table 3 below.

The properties of the seedlings were evaluated by the average length of the seedlings, the color of the seedlings, and the tension of the roots of the seedlings.
The length of the seedling was measured by measuring the length of the above-ground part of the seedling using a ruler. The color of the seedlings was visually evaluated. The root tension was visually evaluated. ○ means good, △ means normal, and × means bad. In all cases where the proportion of foamed glass was 10% by volume, the length of the seedlings was about 10 cm, the color of the seedlings was yellowish green, and the root tension was good. In all cases where the proportion of foamed glass was 30% by volume, the length of the seedlings was about 8.5 cm, the color of the seedlings was yellowish green, and the root tension was normal. No significant difference was observed between the seedlings and the comparative examples (without using foamed glass).

In winter, the following sludge compost was applied to paddy fields in advance at 500 kg per roll.
The amount of sludge compost is 2.9% by mass of nitrogen, 5.5% by mass of phosphoric acid, 0.5% by mass of potassium, 5.9% by mass of lime, 0.9% by mass of bitter soil, and 40.4% by mass of organic matter per 20 kg. , Contains 28.6% by mass (pH 7.8) of water.
The paddy field was sprayed with a herbicide before planting. Each of the above-mentioned seedlings was planted in the above-mentioned paddy field, for example, in late June, more specifically on June 21, using a rice transplanter. Hereinafter, the cultivation plot in which the seedlings grown using the paddy rice cultivation soil of Examples 1 to 10 are planted is referred to as an implementation plot, and the cultivation plot in which the seedlings grown using the paddy rice cultivation soil of Comparative Example 1 are planted. Is also called a comparison zone.
After that, during the period from rice planting to harvesting, damage confirmation observations such as snail damage and windthrow damage were carried out.
Approximately three and a half months after rice planting, for example, in early October, more specifically, on October 13, rice was harvested using a combine harvester. In the implementation group and the comparison group, 10 strains were arbitrarily cut by hand at a location about 15 m from the southern end where there was little collapse, and used as a sample for measuring the average number of rice plants and the average amount of paddy.

Evaluation of average number of standing rice and average amount of paddy The hand-cut rice of Examples 1 to 10 and Comparative Example 1 described above was dried by hanging for 10 days, and then threshed by hand. The number of standings and the mass of paddy were measured. Among each of the 10 strains, the average value of each of the 8 strains excluding the maximum value and the minimum value was taken as the average value of the target number of rice plants (plants / strain) and the amount of paddy (g / strain).
The results are shown in Table 4 below.

Evaluation of taste Using a far-infrared analyzer, the amylose, protein, water content, and fatty acid content of each of the white rice of Examples 1 to 10 and Comparative Example 1 were measured, and the taste was calculated using the taste equation. % Is mass%. The results are shown in Table 5.

Evaluation by Eating Comparison Rice cooked using each of the paddy rice cultivation soils of Examples 1 to 10 and Comparative Example 1 was cooked and compared by eating with 13 panelists. The eating comparison was carried out so that the panelists could not understand the correspondence between Examples 1 to 10 and Comparative Example 1 and rice. As evaluation items, 13 panelists evaluated whether they felt "delicious", "clean", "soft", "mochimochi", "firm", or "scented". When I felt like that, I cast one vote. Thirteen panelists can cast as many votes as they like, and there is no limit to the number of votes. The "rice yield" of the yield was taken into consideration. Therefore, the evaluation items are 7 items.
One point was given to the top two for each item.
"Delicious" was 1 point in Examples 1, 8 and 9.
"Refreshing" was 1 point in Examples 1, 6, 7, and 9.
"Soft" was 1 point in Examples 2, 3 and 5.
As for "mochimochi", Examples 8 and 10 and Comparative Example 1 scored 1 point.
"Solid" was 1 point in Examples 6 and 9.
Examples 1 and 9 scored 1 point for "good fragrance".
The "yield amount" was 1 point in Examples 5 and 9.
Example 9 was the best with 5 points, Example 1 was the second best with 3 points, and Examples 6 and 8 were the third best with 2 points.

No significant difference could be found when growing seedlings from paddy, whether the soil for paddy rice cultivation of Examples 1 to 10 was used or the soil for paddy rice cultivation of Comparative Example 1 was used. In all cases, the length of the seedlings, the color of the seedlings, the tension of the roots of the seedlings, etc. were almost the same.

When seedlings were planted in paddy fields and paddy rice was cultivated with the soil for paddy rice cultivation of Examples 1 to 10 attached to the roots, the yield could be increased with almost no deterioration in taste. In particular, in Examples 9, 1, 6 and 8, the yield was increased by 10% or more as compared with the case of using the paddy rice cultivation soil of Comparative Example 1, and the result of eating comparison was more delicious. rice field.

When the soil for paddy rice cultivation according to the embodiment of the present invention is used, the yield of rice is improved and the taste is not significantly deteriorated (preferably, the taste can be maintained). Further, when the paddy rice cultivation method of the embodiment of the present invention is used, the yield of rice is improved and the taste is not significantly deteriorated (preferably, the taste can be maintained) without requiring any special water level adjustment or the like. , Paddy rice can be easily cultivated.

Claims (14)

Cultivated soil for paddy rice cultivation, including a porous body with sedimentation. The hilling for paddy rice cultivation according to claim 1, wherein the porous body has a specific density of 0.4 or more. The hilling for paddy rice cultivation according to claim 1 or 2, wherein the porous body contains an inorganic substance. The hilling for paddy rice cultivation according to any one of claims 1 to 3, wherein the porous body contains a foam containing silicon dioxide as a main component. The hilling for paddy rice cultivation according to claim 4, wherein the foam contains foam glass. The hilling for paddy rice cultivation according to any one of claims 1 to 5, wherein the size of the porous body is 30 mm or less. The hilling for paddy rice cultivation according to any one of claims 1 to 6, wherein the porous body has pores of 0.1 to 1000 μm. The hilling for paddy rice cultivation according to any one of claims 1 to 7, which contains 5 to 30% by volume of a porous body. A method for cultivating paddy rice, which comprises cultivating paddy rice in a paddy field using the soil for paddy rice cultivation according to any one of claims 1 to 8. The paddy rice cultivation method according to claim 9, which comprises cultivating paddy rice by entwining the cultivation soil for paddy rice with the roots of the paddy rice. Growing paddy rice seedlings using paddy rice hilling;
Planting seedlings in paddy fields with soil for paddy rice cultivation;
The paddy rice cultivation method according to claim 9 or 10, which comprises growing seedlings in a paddy field and cultivating paddy rice. The paddy rice cultivation method according to claim 11, which comprises sowing paddy on hilling for paddy rice cultivation and growing paddy rice seedlings. The paddy rice cultivation method according to claim 11 or 12, which comprises growing paddy rice seedlings using paddy rice cultivation soil and entwining the roots of the seedlings with the paddy rice cultivation soil. The paddy rice cultivation method according to any one of claims 11 to 13, which comprises planting seedlings in a paddy field together with soil for paddy rice cultivation using a rice transplanter.