JP7141036B2 - Rice production method - Google Patents

Description

The technical field of the present specification relates to rice production methods.

Plasma technology has applications in the fields of electricity, chemistry, and materials. Inside the plasma, ultraviolet rays and radicals are generated in addition to charged particles such as electrons and ions. It has been found that these have various effects on living tissue, including sterilization of living tissue.

For example, Patent Literature 1 discloses a technique for sterilizing microorganisms in water by irradiating water with plasma. Moreover, the plasma device of Patent Document 1 can irradiate plasma into water without causing current to flow in the water.

JP 2009-183867 A JP 2014-195450 A

By the way, in Patent Document 2, when yeast is irradiated with a large amount of atmospheric pressure plasma, the number of viable yeast cells decreases, but when yeast is irradiated with a small amount of atmospheric pressure plasma, the number of viable yeast cells increases. It is stated that In this way, studies have been conducted on the possibility of activating and killing yeast by irradiating with plasma. However, the effects of plasma on other organisms are not necessarily clear.

By the way, rice is mainly consumed as edible rice in Japan. Rice suitable for sake brewing (sake rice) represented by Yamada Nishiki is used for sake brewing. In addition, while domestic rice consumption is on the decline, rice exports are on the rise. On the other hand, in Japan, where the declining birthrate and aging population are rapidly progressing, the number of producers is steadily decreasing, and maintaining productivity is becoming a problem. Under such circumstances, improvement of rice production technology is desired.

The technology of the present specification has been made to solve the problems of the conventional technology described above. That is, the object is to provide a method for producing rice in which the growth of rice is promoted using atmospheric pressure plasma.

The method for producing rice according to the first aspect comprises irradiating rice seeds with non-equilibrium atmospheric pressure plasma to promote germination and growth of rice, wherein the first predetermined For a period of time, physical water absorption is performed to cause the rice seeds to absorb water, and then physiological water absorption is performed to cause the seeds to absorb water at a temperature higher than the physical water absorption temperature for a second predetermined period of time, and the physical water absorption and the physiological water absorption are performed. A rice production method in which seeds are irradiated with a laser for a predetermined short period of time.

In this rice production method, the growth of rice can be promoted. Also, a first group of rice whose seeds have been irradiated with plasma and a second group of rice whose seeds have not been irradiated with plasma can be prepared. In this case, the first group of rice can be harvested early. Therefore, two types of groups with different harvest times can be set, and farmers can intentionally extend the harvest period.

Provided herein is a method of producing rice that aims to promote rice growth using atmospheric pressure plasma.

Figure 1. A is a sectional view showing the configuration of the first plasma generator, and FIG. B is a diagram showing the shape of the electrode. Figure 2. A is a sectional view showing the configuration of the second plasma generator, and FIG. B is a diagram showing the shape of the electrode. FIG. 4 is a diagram for explaining the execution timing of the plasma irradiation process in the first embodiment; FIG. 3 is a diagram for explaining a method of irradiating rice seeds with atmospheric pressure plasma in the first embodiment. FIG. 10 is a diagram for explaining the experimental procedure of Experiment A; 10 is a graph showing the relationship between the irradiation time of atmospheric pressure plasma and the germination rate of rice in Experiment A. FIG. FIG. 10 is a diagram for explaining the experimental procedure of Experiment B; FIG. 10 is a photograph showing how rice germinated in Experiment B. FIG. 1 is a graph (No. 1) showing the relationship between the timing of atmospheric pressure plasma irradiation and the coleoptile length of rice in Experiment B. FIG. 2 is a graph (Part 2) showing the relationship between the timing of atmospheric pressure plasma irradiation and the coleoptile length of rice in Experiment B. FIG. FIG. 10 is a diagram for explaining the experimental procedure of Experiment C; Fig. 10 is a schematic diagram showing the structure of seedlings in Experiment C; 10 is a graph showing the length of leaf sheaths of seedlings in Experiment C. FIG. FIG. 10 is a diagram for explaining the experimental procedure of Experiment D; 10 is a graph showing the number of days of leaf age in Experiment D. FIG. 10 is a graph showing the number of days from sowing to heading in Experiment D. FIG. 4 is a graph showing the yield of brown rice in Experiment D. FIG.

Hereinafter, specific embodiments will be described with reference to the drawings, taking a rice production method as an example. Note that the dimensions and the like of the plasma generator are examples, and numerical values outside the illustrated numerical ranges may be used.

(First embodiment)
A first embodiment will be described. In the rice production method of the first embodiment, rice seeds are directly irradiated with atmospheric pressure plasma. Therefore, first, a plasma irradiation apparatus for irradiating plasma will be described.

1. Plasma device 1-1. First plasma generator Fig.1. A is a sectional view showing a schematic configuration of the plasma generator P10. Here, the plasma generator P10 is a first plasma generator that ejects plasma in dots. Figure 1. B is shown in FIG. FIG. 3B is a diagram showing details of the shape of electrodes 2a and 2b of the plasma generator P10 of A. FIG.

The plasma generator P10 has a housing portion 10, electrodes 2a and 2b, and a voltage application portion 3. As shown in FIG. The housing part 10 is made of a sintered body made of alumina (Al ₂ O ₃ ). The shape of the housing portion 10 is cylindrical. The inner diameter of the housing part 10 is 2 mm or more and 3 mm or less. The thickness of the housing part 10 is 0.2 mm or more and 0.3 mm or less. The length of the housing part 10 is 10 cm or more and 30 cm or less. A gas introduction port 10i and a gas ejection port 10o are formed at both ends of the housing portion 10 . The gas inlet 10i is for introducing gas for generating plasma. The gas ejection port 10o is an irradiation section for irradiating the outside of the housing section 10 with plasma. The direction in which the gas moves is the direction of the arrow in the figure.

Electrodes 2a and 2b are a counter electrode pair arranged to face each other. The length of the electrodes 2a and 2b in the facing surface direction is smaller than the inner diameter of the casing 10. As shown in FIG. For example, it is about 1 mm. The electrodes 2a, 2b are shown in FIG. As shown in B, a large number of recesses (hollows) H are formed in each of the facing surfaces. Therefore, the facing surfaces of the electrodes 2a and 2b have fine irregularities. The depth of this recess H is about 0.5 mm.

The electrode 2a is arranged inside the casing 10 and near the gas introduction port 10i. The electrode 2b is arranged inside the casing 10 and in the vicinity of the gas ejection port 10o. Therefore, in the plasma generator P10, the gas is introduced from the opposite side of the facing surface of the electrode 2a and the gas is ejected to the opposite side of the facing surface of the electrode 2b. The distance between the electrodes 2a and 2b is, for example, 24 cm. The distance between the electrodes 2a, 2b may be smaller.

The voltage applying section 3 is for applying an AC voltage between the electrodes 2a and 2b. The voltage application unit 3 boosts the voltage to 9 kV using a commercial AC voltage of 60 Hz and 100 V, and applies a voltage between the electrodes 2a and 2b.

When a rare gas such as argon is introduced from the gas introduction port 10 i and a voltage is applied between the electrodes 2 a and 2 b by the voltage applying section 3 , plasma is generated inside the housing section 10 . Figure 1. A plasma generation region P is defined as a region in which plasma is generated, as indicated by diagonal lines A. FIG. The plasma generation region P is covered with the housing portion 10 .

1-2. Second plasma generator Fig.2. A is a sectional view showing a schematic configuration of the plasma generator P20. Here, the plasma generator P20 is a second plasma generator that linearly ejects plasma. Figure 2. B is shown in FIG. 4 is a partial cross-sectional view in a cross section perpendicular to the longitudinal direction of the plasma generation region P of the plasma generator P20 of A. FIG.

The plasma generator P<b>20 has a housing portion 11 , electrodes 2 a and 2 b and a voltage application portion 3 . The housing part 11 is made of a sintered body made of alumina (Al ₂ O ₃ ). A gas introduction port 11i and a large number of gas ejection ports 11o are formed at both ends of the housing portion 11 . The gas inlet 11i is shown in FIG. It has a slit shape with the left-right direction of A as the longitudinal direction. The width of the slit from the gas introduction port 11i to just above the plasma generation region P (the width in the left-right direction in FIG. 2.B) is, for example, 1 mm.

The gas ejection port 11o is an irradiation section for irradiating the outside of the housing section 11 with plasma. The gas ejection port 11o is cylindrical or slit-shaped. The gas ejection port 11o in the case of a cylindrical shape is formed in a straight line along the longitudinal direction of the plasma generation region. The inner diameter of the gas ejection port 11o is within the range of 1 mm or more and 2 mm or less. Moreover, in the case of a slit shape, it is preferable that the slit width of the gas ejection port 11o is 1 mm or less. A stable plasma is thereby formed. The gas introduction port 11i introduces gas in a direction intersecting a line connecting the electrodes 2a and 2b.

The electrodes 2a and 2b and the voltage applying section 3 are the same as those of the plasma generator P10 shown in FIG. Similarly, a commercial AC voltage is used to apply a voltage between the electrodes 2a and 2b. Thereby, the plasma can be ejected in a straight line.

The plasma generator P20 for ejecting plasma in a straight line is shown in FIG. By arranging them in a row in the left-right direction of B, plasma can be ejected in a plane over a certain rectangular area.

2. Plasma Generated by Plasma Generator The plasma generated by the plasma generators P10 and P20 is non-equilibrium atmospheric pressure plasma. Here, atmospheric pressure plasma refers to plasma having a pressure within the range of 0.5 to 2.0 atmospheres.

In this embodiment, Ar gas is mainly used as the plasma generating gas. Electrons and Ar ions are, of course, generated inside the plasma generated by the plasma generators P10 and P20. The Ar ions then generate ultraviolet rays. Moreover, since this plasma is emitted into the atmosphere, it generates oxygen radicals, nitrogen radicals, and the like.

The plasma density of this plasma is in the range of 1×10 ¹⁴ cm ⁻³ to 1×10 ¹⁷ cm ⁻³ . The plasma density of plasma generated by dielectric barrier discharge is about 1×10 ¹¹ cm ⁻³ or more and 1×10 ¹³ cm ⁻³ or less. Therefore, the plasma density of the plasma generated by the plasma generators P10 and P20 is about three orders of magnitude higher than the plasma density of the plasma generated by the dielectric barrier discharge. Therefore, more Ar ions are generated inside this plasma. Therefore, a large amount of radicals and ultraviolet rays are generated. This plasma density is almost equal to the electron density inside the plasma.

The plasma temperature at the time of plasma generation is in the range of about 1000K or more and 2500K or less. Also, the electron temperature in this plasma is higher than the gas temperature. Moreover, although the electron density is in the range of 1×10 ¹⁴ cm ⁻³ to 1×10 ¹⁷ cm ⁻³ , the gas temperature is in the range of 1000 K to 2500 K. The temperature of this plasma is the temperature in the plasma generation region P where plasma is generated. Therefore, the plasma temperature at the position of the object can be made about room temperature by changing the conditions of the plasma and the distance from the gas outlet to the object.

3. Rice Production Method As shown in FIG. 3, in the rice production method of the present embodiment, the rice seeds are directly irradiated with atmospheric pressure plasma during the water absorption process of the rice seeds.

3-1. Germination Step In order to germinate the rice seeds, a water absorption step of soaking the rice seeds in water is carried out. Then, during the water absorption process, the rice seeds are directly irradiated with atmospheric pressure plasma.

3-1-1. Water absorption process The water absorption process is carried out for several days. Then, as will be described later, a plasma irradiation step, which will be described later, is performed during the water absorption step. At the beginning of the water absorption step (about one day), the rice seeds are allowed to absorb water in water at a low temperature of, for example, 0° C. or higher and 10° C. or lower (physical water absorption). The water temperature is preferably about 4°C, for example. Then, in the later stage (about 2 days) of the water absorption step, the rice seeds are allowed to absorb water in water at a temperature of, for example, 25° C. or more and 35° C. or less (physiological water absorption). The water temperature at this time is preferably about 30° C., for example. Rice germinates in the middle of physiological water absorption. The water temperature at physiological water absorption is higher than the water temperature at physical water absorption.

3-1-2. Plasma Irradiation Step As shown in FIG. 4, the plasma irradiation step is carried out during the water absorption step. Specifically, rice seeds C1 that have finished physically absorbing water are directly irradiated with non-equilibrium atmospheric pressure plasma. At this time, the atmospheric pressure plasma is directed toward the embryo E1 of the rice seed C1. For this purpose, the rice embryo E1 and the irradiation ports of the plasma generators P10 and P20 face each other and are irradiated with atmospheric pressure plasma.

The plasma density time product when the rice seed C1 is irradiated with the atmospheric pressure plasma is preferably 6×10 ¹⁶ sec·cm ⁻³ or more and 2×10 ¹⁷ sec·cm ⁻³ or less. This numerical range corresponds to, for example, the case where atmospheric pressure plasma with a plasma density of 2×10 ¹⁶ cm ⁻³ is applied for 3 seconds or more and 10 seconds or less. The plasma density-time product is an amount that roughly defines the amount of plasma products irradiated to the rice seed C1.

Also, the luminous region of the atmospheric pressure plasma may or may not be in contact with the rice embryo E1. The plasma irradiation distance is preferably 5 mm or more and 30 mm or less. The plasma irradiation distance is the distance from the irradiation ports of the plasma generators P10 and P20 to the rice embryo E1. The plasma irradiation distance may be outside the above range. This is because the rice embryo E1 is still irradiated with plasma products.

At the stage of plasma irradiation, the rice seed C1 is in a state of being covered with a husk. Also, the rice seed C1 is in a state before germination.

3-2. Seedling Raising Step Next, the germinated seeds are sown in a nursery. Then grow from seed to seedling.

3-3. Rice planting Well-grown seedlings are planted in paddy fields. Alternatively, it may be grown inside a climate chamber.

3-4. Subsequent Steps After that, the seedlings are grown by normal growing methods.

4. Effects of Plasma Direct Irradiation on Rice By irradiating rice embryos E1 with atmospheric pressure plasma, the growth rate of rice increases, as will be described later. The number of days from the shortened sunshine hours to the emergence of heading is shortened.

Therefore, for example, two groups are established: (group a) paddy fields for cultivating plasma-treated rice and (group b) paddy fields for cultivating non-plasma-treated rice. Thus, after harvesting the group a rice that can be harvested early, the group b rice that is usually harvested can be harvested. In this way, it is possible to intentionally shift the rice harvest time. Therefore, the burden on farmers is reduced.

In addition, since the number of days from the time of sunshine to the emergence of heading is short, it may be possible to produce rice even in areas with short summers. In other words, the northern limit of each rice variety may be improved.

5. Modification 5-1. Rice Husk In the present embodiment, a rice seed C1 with a husk attached thereto is irradiated with plasma. However, the rice seeds may be irradiated with plasma after the husk is removed.

5-2. Germination of rice Rice embryos E1 may be irradiated with plasma after the rice seeds C1 have germinated.

5-3. Arrangement of Rice When irradiating rice with plasma, the rice seeds are arranged with the rice embryo E1 facing upward. Then, it is preferable to irradiate the rice embryo E1 with the atmospheric pressure plasma with the irradiation ports of the plasma generators P10 and P20 facing downward. For example, it is easy to irradiate rice embryos E1 with plasma using the pen-type plasma generator.

5-4. Miniaturized Plasma Generator The plasma generators P10, P20, etc. may be further miniaturized. By sufficiently reducing the size, a pen-type plasma generator can be manufactured. Even in that case, plasma densities equivalent to those of the plasma generators P10 and P20 can be obtained.

5-5. Combination The above modifications may be combined as appropriate.

1. Experiment A (plasma irradiation time)
1-1. Rice In this experiment, Yamada Nishiki (rice variety) suitable for sake brewing was cultivated.

1-2. Rice Water Absorption Process First, rice seeds were immersed in water at 4° C. overnight (physical water absorption). Thereafter, the rice seeds were immersed in water at 30°C for 2 days (physiological water absorption). At this stage, the rice seeds germinated. In other words, rice seeds germinated during physiological water absorption.

1-3. Direct Plasma Irradiation As shown in FIG. 5, rice seed embryos were directly irradiated with atmospheric pressure plasma immediately before physiological water uptake. At that time, the plasma generator P20 was used. The plasma density in plasma generator P20 was 2×10 ¹⁶ cm ⁻³ . The plasma gas was argon gas. The irradiation time was changed as appropriate.

1-4. Experimental Results FIG. 6 is a graph showing the relationship between the irradiation time of atmospheric pressure plasma and the germination rate of rice. The horizontal axis of FIG. 6 is the plasma irradiation time. The vertical axis in FIG. 6 is the germination rate of rice. As shown in FIG. 6, irradiation distances of 10 mm, 15 mm and 20 mm were adopted. Note that the notation ctrl in FIG. 6 indicates rice that was not irradiated with plasma.

As shown in FIG. 6, the germination rate of rice tends to decrease as the plasma irradiation time increases. However, when the plasma irradiation time was within 10 seconds, the germination rate of rice was about 80% or more.

In addition, the germination rate of rice tends to decrease slightly as the irradiation distance of plasma decreases. This is considered to correspond to the fact that the longer the plasma irradiation distance is, the lower the plasma density is. As shown in FIG. 6, the effect of the plasma irradiation distance is not so large as compared with the plasma irradiation time.

2. Experiment B (timing of plasma irradiation)
2-1. Water Absorption Process of Rice The variety of rice in Experiment B is the same as in Experiment A. The water absorption process of rice in Experiment B was the same as in Experiment A.

2-2. Direct Plasma Irradiation As shown in FIG. 7, the first plasma irradiation time T1 was set immediately before physiological water absorption, and the second plasma irradiation time T2 was set one day after physiological water absorption. The plasma was irradiated at least at one of the first plasma irradiation timing T1 and the second plasma irradiation timing T2. At the stage of the second plasma irradiation time T2, there are also seeds in which germination, that is, elongation of the coleoptile can be visually confirmed. The plasma generator P20 and other plasma conditions are the same as in Experiment A. In addition, 10 mm was adopted as an irradiation distance.

2-3. Experimental Results FIG. 8 is a photograph showing germination of rice. FIG. 8 shows coleoptile length.

9 and 10 are graphs showing the relationship between the timing of atmospheric pressure plasma irradiation and the coleoptile length of rice. The vertical axis in FIGS. 9 and 10 is the coleoptile length. The graphs of FIGS. 9 and 10 are results of experiments performed on different days.

In FIGS. 9 and 10, the notation "5 s" means that plasma irradiation was performed for 5 seconds during the first plasma irradiation timing T1, and no plasma irradiation was performed during the second plasma irradiation timing T2. ing. The notation of "10 s" is also the same, although the irradiation time per time is different. The expression “5s×2” means that the plasma irradiation was performed for 5 seconds at both the first plasma irradiation timing T1 and the second plasma irradiation timing T2. The notation of “10 s×2” is also the same, although the irradiation time per time is different. The notation "5 s (+1 d)" means that no plasma was irradiated during the first plasma irradiation timing T1, and plasma irradiation was performed for 5 seconds during the second plasma irradiation timing T2.

As shown in FIGS. 9 and 10, when plasma was not irradiated (ctrl), the coleoptile length was about 6 to 7 mm. When plasma was irradiated for 5 seconds at the first plasma irradiation time T1, the coleoptile length was about 11 mm. When the plasma was irradiated for 5 seconds at the second plasma irradiation time T2, the coleoptile length was about 11 mm. When the plasma was irradiated for 5 seconds each at the first plasma irradiation time T1 and the second plasma irradiation time T2, the coleoptile length was about 12 mm. When the plasma was irradiated for 10 seconds each at the first plasma irradiation timing T1 and the second plasma irradiation timing T2, the thickness was about 8 mm. When plasma was irradiated for 10 seconds at the first plasma irradiation time T1, the coleoptile length was about 10 mm.

Thus, when a small amount of plasma is irradiated, the coleoptile grows sufficiently large. In addition, when the plasma was irradiated for 5 seconds each at the first plasma irradiation timing T1 and the second plasma irradiation timing T2, the coleoptile became the longest. Thus, the growth of rice is promoted by irradiating plasma.

3. Experiment C (seedling)
3-1. Water absorption process of rice The variety of rice was Yamada Nishiki. The water absorption process of rice in Experiment C is the same as in Experiment A.

3-2. Direct Irradiation of Plasma As shown in FIG. 11, rice seed embryos were directly irradiated with atmospheric pressure plasma immediately before physiological water uptake. The plasma generator P20 and other plasma conditions are the same as in Experiment A. Note that the irradiation time was changed as appropriate.

3-3. Raising seedlings The seedlings were then grown inside a climate chamber for two weeks. The artificial weather device has fluorescent LED lighting, metal halide lamps, and control software. Control software can control the daylight hours of these lights. The temperature of the climate chamber was 30°C.

3-4. Experimental Results FIG. 12 is a schematic diagram showing the structure of seedlings. The seedling has a first incomplete leaf, a second leaf sheath, a third leaf sheath, and a fourth leaf sheath.

FIG. 13 is a graph showing the length of leaf sheaths of young seedlings. The vertical axis in FIG. 13 is the leaf sheath length. As shown in FIG. 13, the second leaf sheath has a substantially constant length regardless of plasma irradiation. The length of the 3rd and 4th leaf sheaths in the plasma-irradiated seedlings is longer than that in the plasma-unirradiated seedlings.

Also, when the plasma irradiation time is 3 seconds or more and 10 seconds or less, the lengths of the third leaf sheath and the fourth leaf sheath are sufficiently long.

Thus, by irradiating the rice seed embryo with atmospheric pressure plasma, the length of the third leaf sheath and the fourth leaf sheath increases. That is, the growth of rice is promoted.

4. Experiment D (early harvest)
4-1. Water Absorption Process of Rice The variety of rice in Experiment D is the same as in Experiment A. The water absorption process of rice in Experiment D was the same as in Experiment A.

4-2. Direct Plasma Irradiation As shown in FIG. 14, rice seed embryos were directly irradiated with atmospheric pressure plasma immediately before physiological water uptake. In addition, the first plasma irradiation timing T1 was set immediately before the physiological water absorption, and the second plasma irradiation timing T2 was set one day after the physiological water absorption. The plasma generator P20 and other plasma conditions are the same as in Experiment A. In addition, 10 mm was adopted as an irradiation distance.

4-3. Raising seedlings After growing the seedlings in the mini-plant, the seedlings were grown inside the artificial climate chamber. The weather equipment is the same as in Experiment C. As shown in FIG. 14, they were divided into two groups in the middle of growing. The first group is seedlings grown under normal conditions. The second group is seedlings grown under early, short day conditions. In general, daylight hours become shorter from summer to autumn. Therefore, when growing seedlings using an artificial weather device, a long-day period (corresponding to summer) and a short-day period (corresponding to autumn) are set. In the second group, the long-day period was set short, and the animals shifted to the short-day period early. In other words, early short days correspond to cultivation in areas with short summers. The length of daylight during the long-day period (noon: light period) was 14 hours. The sunshine duration during the short-day period (noon: light period) was 10 hours. Table 1 shows the long-day and short-day conditions.

[Table 1]
Conditions Day length Temperature (day) Temperature (night)
Long day conditions 14 hours 30°C 25°C
Short day conditions 10 hours 28°C 25°C

4-4. Experimental Results FIG. 15 is a graph showing the passage of days of leaf age. The horizontal axis of FIG. 15 is the date. The vertical axis in FIG. 15 is leaf age. The upper diagram in FIG. 15 shows leaf ages under normal cultivation conditions. The lower diagram in FIG. 15 shows the leaf age under the early short-day cultivation conditions.

As shown in the upper part of FIG. 15, seedlings under normal cultivation conditions were cultivated under long-day conditions until 12 weeks after seeding, and under short-day conditions from 13 weeks. As shown in the lower part of FIG. 15 , the seedlings under the early short-day cultivation conditions were cultivated under long-day conditions until 9 weeks after seeding, and then under short-day conditions from 10 weeks. In this way, in the early short-day condition, the shift to the short-day condition is carried out at an early stage.

In addition, the control group in FIG. 15 is a seedling which was not subjected to plasma irradiation.

FIG. 16 is a graph showing the number of days from sowing to heading. Under the growth conditions of early short days, the ears emerged in about 93 days from sowing regardless of plasma irradiation. On the other hand, under normal growth conditions, irradiation with plasma shortened the time from sowing to heading. The rice plants irradiated with plasma for 10 seconds at the first plasma irradiation time T1 had the shortest number of days from sowing to heading. The shortened days are about two weeks.

FIG. 17 is a graph showing the yield of brown rice. As shown in FIG. 17, the yield of brown rice in plasma-irradiated rice tends to be greater than the yield of brown rice in the control plot that is not irradiated with plasma.

5. Summary of Experiments As described in Experiments B and C, the growth of rice seedlings is enhanced by using direct irradiation of rice seeds with plasma. This indicates that the rice is growing early.

Also, as described in Experiment D, the time to heading is shortened by using direct plasma irradiation of rice seeds. In other words, the use of plasma shortens the time to harvest.

Therefore, for example, by providing a paddy field in which rice is irradiated with plasma and a paddy field in which rice is not irradiated with plasma, the harvesting times can be shifted. In other words, the harvesting of rice may be started from the paddy field in which the rice is irradiated with plasma, and then the rice harvesting in the paddy field in which the rice is not irradiated with plasma. Thus, the use of the technology of the present specification improves workability for farmers.

In addition, as explained in Experiment D, direct irradiation of rice seeds with plasma tends to increase the yield of rice.

(Appendix)
The method for producing rice in the first aspect has a plasma irradiation step of irradiating rice seeds with atmospheric pressure plasma.

In the method for producing rice according to the second aspect, in the plasma irradiation step, the embryo of the rice seed is irradiated with atmospheric pressure plasma.

The method for producing rice in the third aspect has a water absorption step of causing rice seeds to absorb water. A plasma irradiation step is performed in the middle of the water absorption step.

In the rice production method of the fourth aspect, the plasma irradiation step is performed before the rice seeds germinate.

P10, P20...Plasma generators 10, 11...Case parts 10i, 11i...Gas introduction ports 10o, 11o...Gas ejection ports 2a, 2b...Electrode P...Plasma generation region H...Recess (hollow)
C1... Seed E1... Embryo

Claims (6)

Atmospheric pressure on rice seedsnonequilibriumrice by irradiating it with plasmapromote the growth of Rice production methodin
Before the plasma irradiation, physical water absorption is performed for a first predetermined time to cause the rice seeds to absorb water,
Thereafter, physiological water absorption is performed at a temperature higher than the physical water absorption temperature for a second predetermined time, causing the seeds to absorb water;
Between the physical water absorption and the physiological water absorption, the seeds are irradiated with the plasma for a predetermined short time.
A rice production method characterized by: During the period of physiological water absorption, the plasma is applied to the seeds for a predetermined short period of time. irradiate
According to claim 1, characterized in that Rice production method. 3. The method according to claim 1 or 2, wherein the temperature of the physical water absorption is 0° C. or higher and 10° C. or lower. Rice production method. 4. The method according to any one of claims 1 to 3, wherein the physiological water absorption temperature is 25°C or higher and 35°C or lower. Rice production method. 5. The rice production method according to any one of claims 1 to 4, wherein the predetermined short time is 10 seconds or less. 6. The method for producing rice according to any one of claims 1 to 5, wherein the seeds are irradiated with the plasma so that embryos of the seeds are stimulated by the plasma.

Images