JP2020010623A - Direct seeding coated seed and direct seeding culture method - Google Patents

Abstract

To provide seeds capable of overcoming shortcomings of both of prior seed coating using iron and seed coating using Bengala and Molybdenum without damaging advantages of both of them.SOLUTION: The inventors have found that, by coating seeds with an iron powder-containing substance, and then coating the seeds with a molybdenum containing substance, it is possible to overcome shortcomings of both of prior seed coating using iron and seed coating using Bengala and Molybdenum without damaging advantages of both of them, thereby achieving and completing the invention. Therefore, the invention provides coated seeds for direct seeding comprising coating of the iron powder-containing substance for coating seeds and coating of the Molybdenum containing substance for coating outside of the coating of the iron powder-containing substance.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a coated seed suitable for direct sowing and a method for direct sowing.

  Conventionally, in rice cultivation, seedlings have been produced from seeds, which have been planted in paddy fields for cultivation. In seedling production, a great deal of labor and time are required in the process of sowing, germinating and raising seedlings.

  There is a demand for labor saving and cost reduction of rice cultivation, and various cultivation methods have been studied and developed. Among them, direct sowing cultivation that does not require seedling production is expected. In direct sowing cultivation, rice is cultivated by sowing seeds directly in rice fields without seedling production. In the past, in direct sowing cultivation, germinated seeds were sown on the soil surface of paddy paddy fields. When sown on the soil surface, oxygen is easily supplied to the seed, and germination and growth are good. However, seeds sown on the surface tend to float in paddy fields. Therefore, in surface sowing, dropping water in a paddy field causes bird damage such as sparrows, which has been a problem.

  In order to solve the above-mentioned problems in direct sowing cultivation, techniques for iron-coding seeds have been developed. Iron-coated seeds are produced by coating seeds with a mixture of iron powder and salts such as plaster of Paris together with moisture. The iron powder coated on the seed surface is fixed to the surface by rusting due to oxidation. Gypsum becomes easy to coat by reacting with water and solidifying. Salts and water also contribute to the oxidation reaction.

  The weight of the iron-coated seed thus produced is increased by iron, so that the seed does not float easily even when sown on the soil surface. Further, since the surface is hardened by the iron coating, bird damage can be prevented. In addition, there are reports that the iron coating can prevent seed-borne infectious diseases.

  However, iron-coated seeds have a disadvantage that they are susceptible to lodging because they are sown on the soil surface. When seeds are sown in the soil to avoid lodging, paddy fields have low oxygen in the soil and harmful sulfides are generated from sulfate ions. .

  On the other hand, it has been found that coating a rice seed with a molybdenum compound can suppress generation of harmful sulfides in flooded direct sowing cultivation (Non-Patent Document 1 and Patent Document 1). By coating the seeds with a molybdenum compound that releases molybdate ions in order to suppress the formation of sulfides, the seedling establishment was improved even when submerged and sown in soil. However, the coating of seeds with a molybdenum compound is not a method having a better seedling establishment effect than the conventional method, and has no effect on causes other than sulfides that inhibit seedling establishment.

WO2011 / 093341

Yoshitaka Hara (National Institute of Agricultural Research, Kyushu Okinawa Agricultural Research Center), Combined effect of molybdenum on seeding in flooded rice paddy using iron and oxygen generating agent-Inhibition of seedling establishment by gypsum and avoidance by molybdenum-, Abstract and Data of Papers to be Presented at the Meeting of the Society. Japanese Journal of Crop Science Volume: 232nd, Page: 118-119, 2011

  An object of the present invention is to provide a seed that overcomes the disadvantages of the conventional iron-coated seeds and the advantages of the vapor-coated seeds without impairing any of them. Iron-coated seeds must be sown on the surface and have the disadvantage that they tend to lodge during the growth process, while the vegetation-coated seeds are vulnerable to bird damage and vulnerable to seed-borne diseases. It is intended to provide a seed that has overcome the above.

  By coating the seeds with an iron powder-containing material and then with a molybdenum-containing material, the present inventor has overcome the disadvantages of both iron-coated seeds and batoli-coated seeds without impairing them. We have found that we can overcome this and completed the present invention.

  That is, the present invention provides an iron coating layer containing an iron powder, which covers seeds, and an outer coating containing a molybdenum-containing material and / or a tungsten-containing material that supplies oxo anions, which coats the outside of the iron coating layer. A coated seed for direct sowing, comprising:

  The present invention also provides the coated seed for direct sowing, wherein the outer coating layer is a mixture of the iron oxide-containing material, molybdenum trioxide and polyvinyl alcohol.

  The present invention also provides the coated seed for direct sowing, wherein the seed is a seed of a Poaceae plant.

  Further, the present invention provides a direct sowing method, wherein the seed is coated with an iron powder-containing material, and the iron-coated seed is coated with a molybdenum-containing material and / or a tungsten-containing material that supply an oxoanion. Provided is a method including an outer coating step of coating, a step of drying the outer-coated seed, and a step of sowing the steam-dried seed in soil.

  Further, the present invention provides the above direct sowing method, wherein the molybdenum-containing material and / or tungsten-containing material that supplies the oxo anion is a mixture of an iron oxide-containing material, molybdenum trioxide, and polyvinyl alcohol.

  Further, the present invention provides the above direct sowing cultivation method, wherein the seed is a seed of a Poaceae plant.

  ADVANTAGE OF THE INVENTION According to the coating seed for direct sowing of this invention, the shortcoming of both iron coating and a vegetation coating is overcome, soil sowing is possible, it is strong in lodging, high germination rate, strong in bird damage, and derived from seed. The present invention can provide seeds for direct sowing that are resistant to the disease. Further, according to the direct sowing method of the present invention, an inexpensive and simple direct sowing cultivation method can be provided by the effect of the seed.

FIG. 1 is a cross-sectional view schematically illustrating a coated state of a coated seed for direct sowing of the present invention. The photograph which shows an example of the drying process in manufacture of the coating seed for direct sowing of this invention. The photograph which shows an example of the coating seed for direct sowing of this invention. The figure which shows one aspect at the time of sowing the coating seed for direct sowing in a paddy field in the direct sowing cultivation method of this invention. The figure which shows one aspect at the time of seeding the soil of the coating seed for direct sowing of this invention. The photograph which shows the germination state of the coating seed for direct sowing of the present invention.

  In the coated seed 1 for direct sowing of the present invention, the seed 2 is covered with an iron coating layer 3 containing a substance containing iron powder. Further, the coated seed 1 for direct sowing of the present invention is coated on the outside of the iron coating layer 3 with an outer coating layer 4 containing a molybdenum-containing material and / or a tungsten-containing material that supplies oxo anions. FIG. 1 is a cross-sectional view schematically showing a coated state of a coated seed for direct sowing of the present invention.

  In the present invention, the term “coating” refers to coating with any material formed on the surface of a seed or the like. For example, an iron coating and a molybdenum coating refer to a coating formed by a material containing iron and molybdenum, respectively. The coating layer refers to a layer formed by coating. Covering refers to covering an arbitrary material on the surface of a seed or the like.

  The seed used for the coated seed for direct sowing of the present invention can be a seed of any plant. The seed can be, in particular, the seed of a crop grown in flooded conditions, such as a paddy field. For example, the seed can be a grass family plant such as rice, barley and wheat, a legume plant such as soybeans and red beans, a polygonal plant such as buckwheat, and a cruciferous plant such as rape and cabbage.

  The seed used for the coated seed for direct sowing of the present invention can be a seed in any germinated state. In direct sowing cultivation, seeds subjected to germination treatment are often used for the purpose of shortening the time from seed sowing to germination. The seed used for the coated seed for direct sowing of the present invention can also be a seed that has been subjected to germination treatment such as soaking germination treatment. For example, in the case of rice, seeds (soaked in well water of 15 to 16 ° C. for 3 days) can be used as seeds (dry rice) so that the integrated temperature of the daily average temperature is about 45 ° C. The seed used for the coated seed for direct sowing of the present invention can also be used after the seed soaked as described above is wet or once dried.

  In the coated seed for direct sowing of the present invention, the above-mentioned seed is coated with a substance containing iron powder. The iron powder-containing material used in the coated seed for direct sowing of the present invention can be an iron powder-containing material used for a known iron coating technique in direct sowing cultivation. The type of iron powder is reduced iron powder, which is obtained by heating and reducing high-grade iron oxide. As the iron powder, iron powder of any size used in the art can be used, for example, iron powder having a small particle size of 100 μm or less can be used. As the iron powder used in the present invention, commercially available iron powder for agricultural use can be used, for example, S91 iron powder which is an iron powder for coating of JFE Steel, DSP317 iron powder of Dowa Iron Powder Industry, and Tetsugen for agricultural use. Iron powder and iron powder for agriculture of Daitetsu Industries can be used.

  The iron powder-containing material used in the coated seed for direct sowing of the present invention may be a material of iron powder alone or a mixture with a material other than iron powder. In the conventional iron coating technology, an iron powder-containing material obtained by mixing calcined gypsum with iron powder is used as an oxidation accelerator for iron powder. In this iron coating technique, iron powder rusts on the surface of the seed, and the rust plays a role of glue. In conventional iron coating technology, calcined gypsum is used as an oxidation promoter to cause rust. The iron coating with the iron powder content used in the present invention can also be used as a mixture of iron powder and calcined gypsum, whereby the oxidation can be started by adding water when coating the seed with the coating. it can. The material mixed with the iron powder can be any material and can be in any amount. For example, in the case of an iron powder-containing material in which calcined gypsum is mixed with iron powder, it can be used in any ratio with reference to a conventional iron coating technique. For example, 0.1% to 40%, for example 1% to 30%, 5% to 25% and 10% to 20% of calcined gypsum can be mixed with respect to the weight of the iron powder. Usually, calcined gypsum is mixed at about 10% by weight with respect to iron powder, and may be increased to about 40% when iron powder is coarse and hard to adhere to seeds. Conversely, when iron powder is fine, The mixture may be reduced to about 1%.

  Iron powder can be applied to seeds in a manner similar to conventional iron coating techniques. The iron powder can be coated, for example, as described in “Iron-Coated Direct Sowing Manual 2010 (edited by National Agriculture and Food Technology Research Institute Kinki Chugoku-Shikoku Agricultural Research Center)”. For example, when a mixture of iron powder and plaster of Paris is coated on a seed, a mixture of 0.5 weight of iron powder and 0.1 weight of plaster of Paris is coated per 1 weight of seed. The coating ratio of seed to iron powder can be from seed: iron powder = 1: 0.1 to 1: 1, such as 1: 0.3 to 1: 0.7, such as 1: 0.5 and 1: 0.6.

  To coat the seeds with iron powder, for example, a mixer can be used. First, seeds are put into a mixer, and the mixer is rotated. Next, the iron powder (or mixture) is charged into the mixer. The iron powder is put into the mixer several times (for example, three times) so that it is sufficiently mixed. Further, while rotating the mixer, water is sprayed using an atomizer or the like so that the iron powder is appropriately moistened. Rotate while spraying water until the powdery material no longer adheres to the seeds. When the material is sufficiently adhered, an iron coating is formed on the surface of the seed. After the iron coating, there is no need to coat the finished plaster of Paris as with a conventional iron coating, and the outer coating of the next step can be substituted.

  The iron-coated seed may be subsequently subjected to the following outer coating or may be dried once. Seeds coated with water as described above generate heat by oxidizing iron powder (reduced iron) on the surface. Therefore, if the seeds are left after coating, they will die due to heat generation. In order to prevent this, drying is performed while releasing heat. For example, heat may be dissipated by putting an iron-coated seed in a seedling box or the like and spreading it thinly. When using a seedling box, as shown in FIG. 2, approximately 1 kg of iron-coated seeds may be spread in one seedling box to dissipate heat. If the iron powder on the surface of the seeds is not sufficiently oxidized and the iron coating layer may be broken, the seeds spread in a seedling box or the like may be sprinkled again to promote oxidation. When the seeds are dried so that the seeds do not die due to heat, the iron-coated seeds become brown and rusted. In addition, the iron-coated seeds can be dried in this state or stored in a low-temperature storage, so that the seeds can be stored for a long period of time while maintaining the germination rate.

  Seeds coated as described above are subsequently subjected to the following outer coating.

  Iron-coated seeds are further covered by an outer coating. The outer coating used in the present invention comprises molybdenum-containing and / or tungsten-containing materials that supply oxo anions. It is known that oxygen in the soil of paddy paddy fields is insufficient, and if this condition continues, sulfides, which are harmful to plants, are generated from sulfate ions, which inhibit seedling establishment. This sulfide formation can be suppressed by molybdate ions and tungstate ions. Therefore, if molybdenum-containing and / or tungsten-containing materials that supply these oxo anions are included in the outer coating, seedling establishment can be stabilized by suppressing sulfide formation. In addition, since the oxo anion is directly provided in soil and moisture by having a coating for supplying oxo anion to the outside, sulfide generation in soil can be efficiently suppressed.

  The molybdenum-containing material and / or tungsten-containing material used for the direct-seeding coated seed of the present invention can be a material used for a known molybdenum-containing material and / or tungsten-containing coating technique in direct sowing cultivation.

  The molybdenum-containing material can be a substance that can supply molybdate ions. The molybdenum-containing material is desirably, for example, metallic molybdenum (simple substance), molybdenum oxide (molybdic anhydride), molybdic acid and its salt, molybdophosphoric acid (phosphomolybdic acid) and its salt, and molybdosilicic acid (silicomolybdic acid) and its salt. Inexpensive and commercially available products include metal molybdenum, molybdenum oxide, molybdic acid, calcium molybdate, magnesium molybdate, ammonium molybdophosphate (ammonium phosphomolybdate), potassium molybdophosphate (potassium phosphomolybdate), ammonium molybdate, It can be one or more selected from sodium molybdate, potassium molybdate, molybdophosphoric acid, sodium molybdophosphate (sodium phosphomolybdate) and molybdosilicic acid. The molybdenum content can be, for example, molybdenum trioxide. Molybdenum trioxide is inexpensive among molybdenum compounds, and can sufficiently suppress generation of sulfide ions. Molybdenum is also a trace element in plants. Therefore, it is also used as a fertilizer and is preferably contained in soil.

  The tungsten-containing material is preferably, for example, metal tungsten, tungsten oxide (tungstic anhydride), tungstic acid and its salt, tungstophosphoric acid (phosphotungstic acid) and its salt, and tungstosilicic acid (silicotungstic acid) and its salt. At low cost and commercially available, it may be one or more selected from slightly soluble metal tungsten, tungsten oxide, tungstic acid, ammonium paratungstate and ammonium tungstophosphate (ammonium phosphotungstate).

  The amount of the molybdenum-containing material and / or the tungsten-containing material that supplies the oxo anion is preferably an amount that does not adversely affect plants and can suppress generation of sulfide ions that damage plants. For example, the molybdenum-containing material and / or tungsten-containing material that supplies the oxoanion may be metal molybdenum, molybdenum oxide, molybdic acid, calcium molybdate, magnesium molybdate, ammonium molybdophosphate, potassium molybdophosphate, metal tungsten, tungsten oxide, tungstate. , Ammonium paratungstate, or ammonium tungstophosphate (ammonium phosphotungstate), in terms of molybdenum or tungsten, 0.01 to 10 mmol, for example, 0.02 to 1 mmol, 0.05 to 0.1 mmol per 1 g of dry weight of seed. Can be the amount of

  The molybdenum-containing and / or tungsten-containing material providing the oxo anions used in the outer coating of the present invention may be a molybdenum-containing or tungsten-containing material, or may be a mixture with other materials. You may.

  The outer coating can contain any material for adhering the coating material to the seed surface, for example. Also, any material that makes the coated layer less likely to collapse when the coated seeds are immersed in water can be included. In addition, it is possible to contain a material that makes the surface of the coated seed easier to adjust to water and thereby makes the coated seed more easily adhere to the soil.

For example, the outer coating can contain polyvinyl alcohol. The polyvinyl alcohol used for the outer coating is, for example, polyvinyl alcohol which is a particulate solid and has a saponification degree of 78 mol% or more. By containing such polyvinyl alcohol in a solid state, the material can be easily adhered to the seed surface, and the disintegration of the seed due to water can be suppressed. The degree of saponification of the polyvinyl alcohol can be from 90 mol% to 98 mol%, for example from 93 mol% to 98 mol% or from 95 mol% to 98 mol%. The degree of saponification (mol%) of polyvinyl alcohol refers to the ratio of each saponified vinyl acetate repeating unit to a hydroxyl group when saponifying polyvinyl acetate to produce polyvinyl alcohol. Further, the degree of polymerization of polyvinyl alcohol is not particularly limited. For example, the degree of polymerization can be 1000 to 5000, 1500 to 3500, 1500 to 2500 or 1700 to 2400. The degree of polymerization of polyvinyl alcohol refers to the number of vinyl acetate repeating units constituting a polymer chain when polyvinyl alcohol is produced by saponifying polyvinyl acetate.

For example, the outer coating can contain a whisk. Benga is iron oxide (Fe ₂ O ₃ ), which can make the coated surface adapt to water and make it easier to sink, thereby allowing the seeds to adhere to the soil. In addition, although the weight can be increased, the coated seed for direct sowing of the present invention has an iron coating and therefore has a sufficient weight.

  As the outer coating used in the present invention, for example, a commercially available metal material (Morishita Bengal Kogyo Co., Ltd.) can be used. The weight material used for the outer coating of the present invention may be, for example, a weight material (0.1 times the weight). The weight of the material is 0.1 times the weight of the seeds, and 0.5% of the weight of the molybdenum trioxide and 1% of the weight of the polyvinyl alcohol (0.1 times the weight of the materials). Including.

  The outer coating can be applied to the seed in a manner similar to the iron coating technique described above. When 0.1 weight of the above-mentioned weight material is coated on the seed, for example, 0.1 weight of the weight material can be coded for 1 weight of the seed. The ratio of seed to outer coating can be seed: outer coating = 1: 0.001-1: 1, such as 1: 0.01-1: 0.7, such as 1: 0.1-1: 0.5.

  The outer coating can be applied to the seed in a manner similar to conventional iron coating techniques. For example, first the seeds with the outer coating iron coated are put into a mixer and the mixer is rotated. The material of the outer coating (such as a mixture containing molybdenum trioxide) is then charged to the mixer. The material of the outer coating is put into the mixer in several portions (eg, three times) to ensure thorough mixing. Further, while rotating the mixer, water is sprayed using an atomizer or the like so that the iron powder is appropriately moistened. Rotate while spraying water until the powdery material no longer adheres to the seeds. The outer coated seeds are subsequently subjected to a drying step. After the outer coating, there is no need to coat the final plaster of Paris as with a conventional iron coating, and the outer coating can be substituted.

  The outer coated seeds are once dried. Drying may be performed, for example, for one day. Drying may also be for a period of several months. The seeds coated with water as described above generate heat by oxidizing iron powder (reduced iron) on the surface of the inner iron coating. Therefore, if the seeds are left after coating, they will die due to heat generation. In order to prevent this, heat may be radiated by placing the seeds coated on the outside in a seedling box or the like and spreading them thinly. For example, as shown in FIG. 2, about 1 kg of seeds may be spread in one seedling box to dissipate heat. On the other hand, drying does not require complete drying. The coating may be moist and may only be dried to the extent that the coating is not broken.

  According to the above procedure, the coated seed for direct sowing of the present invention can be produced. FIG. 3 is a photograph showing an example of the direct-seeded coated seed of the present invention produced by the above procedure.

  The produced coated seed for direct sowing can be directly sowed after the production. In addition, the produced coated seed for direct sowing can be stored for a long period of time while maintaining the germination rate by drying in this state or storing in a low-temperature storage.

  The present invention further provides a direct sowing cultivation method. In the direct sowing method of the present invention, the seed is coated with an iron powder as described above, and the iron-coated seed is coated with a molybdenum-containing material and / or a tungsten-containing material that supplies an oxoanion. The method includes an outer covering step, a drying step for drying the outer-coated seeds, and a step of sowing the dried seeds in soil.

  The iron coating step, the outer coating step, and the drying step can be performed as described for the preparation of the coated seed for direct sowing described above.

  Next, the dried seeds are sown in soil such as a paddy field. Seeding can be performed by any means known in the art, and for example, can be sowed in the same procedure as conventional direct weight sowing. For example, the coated seeds for direct sowing of the present invention are seeded as described in “Rice Paddy Vegetables Direct Sowing Manual” 2016 (Kyushu Okinawa Agricultural Research Center, Agriculture and Food Technology Research Organization). be able to.

  Specifically, seeding can be performed according to the following procedure. First, the rice field is plowed without water, and after about four weeks, the paddy is flooded and roughed, and the next day is planted. Two days later, the coated seed for direct sowing of the present invention is sowed. Water is dropped on the day before sowing, and the seed is sowed with a sowing machine. When seeding a rice field, the seed is sown with a groove in the soil as shown in FIG. Seeding can be performed at an arbitrary seeding interval. For example, 5 to 15 seeds are sown at horizontal intervals of 30 cm, which is a specification of a general sowing machine. The amount of seeds to be sown may be increased or decreased in consideration of the germination rate and the rate of rice standing. For example, in the case of rice, about 7 to 8 grains at 70% rice standing rate, and about 10 grains at 50% rice standing rate are considered appropriate fishing.

  After sowing, leave the soil naturally without actively covering the soil. When the seeds are not sufficiently dried and remain moist, the seeds are preferably sown directly within one hour. During this time, the seed temperature will not rise during sowing and the quality of the seed will not decrease. When sown in a rice field, the temperature of the seeds rises, the quality of the seeds does not decrease, and the germination rate does not decrease. Next, after sowing, the water is flooded for 2 days, and the water is naturally drained to control the water fall for 10 days.

  ADVANTAGE OF THE INVENTION According to the coating seed for direct sowing of this invention, since it has the weight more than an iron coding, a seed does not float in water. Also, since the advantages of the iron coating are not compromised, a hard iron coating can prevent bird damage. In addition, due to the effect of the iron coating, it also has the effect of being resistant to seed-borne diseases. In addition, since it has the advantages of the conventional vapor coating, the establishment of seedlings is stabilized without being affected by sulfide. Furthermore, since the germination rate does not decrease even when seeded in the soil, seeding in the soil instead of on the surface sowing enables the growth that is strong against lodging.

(1. Production of coated seed for direct sowing)
Seed paddy for rice action was coated in the following procedure.

Materials The iron powder used was S91 iron powder for coating (JFE Steel).
As the calcined gypsum, a commercially available product was used.
As the molybdenum-containing material, a metal material (metal material 0.1 times heavy weight, Morishita Benzara Kogyo Co., Ltd.) was used. This material is a material obtained by mixing a molybdenum compound for suppressing the formation of iron oxide (ferric oxide), sulfide, and polyvinyl alcohol as an adhesive for attaching these to seeds. 0.1% by weight of benmori material is used to mix bengar (iron oxide) at 0.1% by weight of seed weight, molybdenum trioxide at about 0.5% by weight of seed weight, and polyvinyl alcohol at 1% by weight of benga weight. That is, it is blended in a ratio of 1 kg of bun, 10 kg of molybdenum trioxide and 10 g of polyvinyl alcohol per 10 kg of weighing material, and used for 100 kg of seeds.

Method Seeds (dry paddy) were soaked in well water at 15-16 ° C for 3 days. The integrated temperature of soaking was 45-48 ° C. 2 kg of iron powder (0.5 times the weight of dry rice) and 200 g of calcined gypsum (0.1 times the weight of iron powder) were previously mixed to prepare a mixture.

  4 kg of seeds were put into a concrete mixer (Maze Taro), and the mixer was rotated. Next, a mixture of iron powder and calcined gypsum was charged into a mixer. The mixture was charged into the mixer in three portions to ensure thorough mixing. In addition, water was appropriately sprayed using a backdrop moving jet. It was rotated while spraying water until the powdery material disappeared. All mixtures were coated on the seeds.

  Next, the above-mentioned iron powder-coated seeds were further coated with a weight material. Specifically, 400 g of a weight material was put into a concrete mixer containing the iron powder-coated seeds. Wet material was put into the mixer in three portions so that it could be mixed well. In addition, water was appropriately sprayed using a backdrop moving jet. It was rotated while spraying water until the powdery material disappeared. All mixtures were coated on the seed. The finished coated seed is shown in FIG. The image of the finished seed is as shown in FIG.

  Next, the molybdenum-coated seeds were dried. As shown in FIG. 2, molybdenum-coated seeds were spread on a seedling box and dried. One bowl of seeds was spread in one seedling box. 4 kg of seeds could be spread over about 11 or 12 seedling boxes. The seeds were dried overnight. Due to this overnight drying, the coating reached practical strength. It was also estimated that the drying could be for several months.

(2. Seeding of coated seeds for direct sowing)
The molybdenum-coated seeds were sown according to the following procedure. Specifically, the rice field was tilled without water, and after about four weeks, the paddy was flooded and the paddy was shaved, and the planting allowance was replaced the next day. Two days later, the molybdenum-coated seeds were sown.

  The seeder used was Kubota's EP4-TC. When sowing the seeds in the rice fields, the seeds were sown with grooves in the soil as shown in FIG. The seeder was fitted with components on the float of the equipment so that a groove with a depth of 10 mm was formed in the rice field.

  In the rice field, 10 seeds were sowed in 4 rows at intervals of 30 cm in width, which is a specification of the seeding machine. Seeding was performed at an interval of 24 cm in the traveling direction of the seeding machine. FIG. 5 is a diagram showing a sowing interval of seeds when sowing a rice field.

  The water was dropped on the day before sowing, and the seeds were sown with a sowing machine. After sowing, the soil was left naturally without actively covering the soil. Seeds were sown directly within one hour. During this time, the seed temperature did not rise at the time of sowing and the quality of the seed did not decrease. When sown in a rice field, the temperature of the seeds increased and the quality of the seeds did not decrease, and the germination rate did not decrease.

  After sowing, the plant was flooded for 2 days, allowed to fall naturally, and managed for 10 days. At this point, sufficient germination was confirmed, as shown in FIG. In addition, a clear increase in the germination rate was observed as compared with the conventional wet-coated seeds.

  After that, the rice was managed in the same manner as in the normal rice cultivation. Thereafter, the seeds did not easily fall down as in the case of the iron-coated seeds, and there was no occurrence of poor seedling establishment.

(3. Results)
According to the coated seed for direct sowing of the present invention, sufficient germination and seedling establishment could be confirmed even though the seed was sown in the soil and flooded in the direct sowing cultivation method.

  In the direct sowing method using the coated seed for direct sowing of the present invention, bird damage caused by sparrows and the like was not confirmed. On the other hand, in a paddy field directly sown with conventional wet-coated seeds, some parts did not germinate due to bird damage such as sparrows.

  Furthermore, in a paddy field directly sown with conventional wet-coated seeds, the seeds near the water source were washed away due to the influence of the water flow during flooding. For this reason, in the conventional wet-coated seeds, no germination was observed near the water source, and there were places where the seeds washed away solidified and germinated around the water source. On the other hand, in the direct sowing cultivation method using the coated seed for direct sowing of the present invention, the seeds were not washed away, and germination was stably observed even near the water source.

  In this direct sowing cultivation method, since seeding was performed in soil, there was no problem of lodging like surface sowing. For this reason, it is considered that the problem of lodging, which had been surface-sown in conventional iron-coated seeds, can be solved by the direct-seeded coated seeds of the present invention.

  Furthermore, the direct sowing cultivation method is considered to have an excellent effect of the iron coating, such as being resistant to seed-related diseases, as compared to conventional vegetation-coated seeds.

  The coated seed for direct sowing of the present invention can be suitably used in direct sowing cultivation in paddy fields and the like.

1 ・ ・ ・ Coated seed
2 ・ ・ ・ Seeds
3 ... Iron coating
4 ・ ・ ・ Outer coating
5 ... Soil
6 groove

Claims (6)

An iron coating layer containing an iron powder-containing material for coating the seeds,
An outer coating layer containing a molybdenum-containing material and / or a tungsten-containing material for supplying oxo anions, which coats the outer surface of the iron coating layer;
A coated seed for direct sowing, comprising:   2. The coated seed for direct sowing according to claim 1, wherein the outer coating layer is a mixture of the iron oxide-containing material, molybdenum trioxide, and polyvinyl alcohol.   3. The coated seed for direct sowing according to claim 1, wherein the seed is a seed of a gramineous plant. Direct sowing cultivation method,
An iron coating step of coating the seed with an iron powder-containing material,
An outer coating step of coating the iron-coated seed with a molybdenum-containing material and / or a tungsten-containing material that supplies oxo anions;
Drying the outer coated seeds,
Sowing the dried seeds in soil,
A method that includes   5. The direct sowing method according to claim 4, wherein the molybdenum-containing material and / or tungsten-containing material that supplies the oxo anion is a mixture of the iron oxide-containing material, molybdenum trioxide, and polyvinyl alcohol. 3. The direct sowing cultivation method according to claim 1, wherein the seed is a seed of a gramineous plant.