JPS63317011A - Coated rice plant seeds for direct sowing into the rice paddy soil submerged with water - Google Patents

Abstract

PURPOSE:To coat rice seeds with a gel by a specific method, thus enabling the coated rice seeds to be cultivated in submerged rice paddies by direct sowing. CONSTITUTION:A rice seed 9 and a bubble 10 are coated with an almost equal volume of hollow sphere gel 8 so that the apparent specific gravity of the whole sphere becomes 1 or higher by controlling the components and the concentrations of the gelling agent. The gel is suitably CMC sodium salt, sodium polyacrylate or sodium alginate and desired to be hardened its surface by dipping the coated rice seeds in an aqueous solution containing Ca<2+> ion to exchange the Na with Ca.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to coated rice seeds that can be sown directly into hot water soil and cultivated as they are.

[Conventional technology and problems]

In Japan, it is customary for rice cultivation to grow seedlings and transplant them into rice fields, and transplant cultivation is carried out on over 99% of the rice cultivation area, but in the world, around 70% of the rice cultivation area is cultivated. Direct sowing cultivation is practiced.

Among the direct FIR cultures, the methods currently used in Japan can be broadly classified as follows.

(a) Direct sowing cultivation in dry fields (b) Cultivation on flooded surface II (C) Direct sowing cultivation in flooded soil These methods are different in terms of rice field condition and sowing depth, and do not require seedling production or rice transplanting, which can save labor. Although they have common strengths, each has a number of problems.

The dry field direct seeding cultivation in (a) is limited to regions with a warm climate, is easily affected by weather conditions and animals, and requires a large amount of water.

In the submerged direct sowing cultivation method (b), depending on the position where the seed rice is planted, many rotting or falling seedlings occur due to lack of oxygen, which reduces the seedling establishment rate.

Also, it is prone to lodging during the harvest season.

Direct sowing cultivation in flooded soil (C1) was proposed as an improved cultivation method of (a) and (bl), in which rice seeds are coated with a mixture of calcium peroxide and calcined gypsum, and the coated seeds are spread over a width of flooded soil. This is a method of sowing seeds to a depth of about 10 mt.

Oxygen is supplied to the rice seeds through long-term chemical changes in calcium peroxide, but there are the following problems.

(1) Calcium peroxide reacts with water to generate oxygen, but calcium hydroxide accumulates in the soil and the soil is stained with lη.

(11) Since the rice seeds are coated in a rotating drum, a large amount of rice can be processed, but a large external force is applied to the seeds, causing them to break.

In addition, conventional direct sowing seeds in flooded soil require preliminary measures such as selection, disinfection, and soaking before being coated, and then are coated with a coating material such as calcium peroxide. Producing direct sown seeds was very time consuming.

The present invention provides coated seeds for direct sowing cultivation in flooded soil that can solve these problems.

[Means for solving problems]

In the present invention, seed rice is coated with a hollow spherical gel coating layer having approximately the same volume as the air bubbles, and the components and concentration of the gel material forming the gel coating layer are adjusted to reduce the apparent specific gravity of the entire gel coating layer to 1. The goal is to make it larger than the above.

[For production]

The rice seeds are protected by a coating agent containing nutrients, fungicides, etc., and are coated with air bubbles, so there is no risk of oxygen deficiency and the germination rate can be increased.

Further, since the gel coating layer has a spherical shape with approximately the same volume, mechanization of seeding is facilitated.

Since the overall apparent specific gravity is greater than 1, the seeds germinate in the soil without floating above the soil after sowing.

〔Example〕

Examples of the present invention will be described below.

Previously, the seeds were coated with a coating material such as calcium peroxide after preparatory measures such as disinfection and seed soaking were performed before being coated, making it very time-consuming to produce seeds for direct sowing in flooded soil. Taking precautionary measures such as disinfection and seed soaking, we focused on the fact that bactericides and germination promoters can be added to the coating agent, and in the present invention, we use coated seeds that perform the preliminary measures and coating at the same time. A gel was used to allow the addition of drug substances.

The gel is water-soluble CMC-Na, polyacrylic acid N
a, Na alginate, etc. are suitable, but since they are all water-soluble, the surface is immersed in a water-soluble solution containing Ca''.
, the surface is hardened by replacing Na.

Also, when seeds germinate, it is necessary to supply oxygen.
Since the method of generating oxidation using chemicals is extremely dangerous, we adopted a method of physically supplying oxygen to the rice seeds by enclosing air bubbles together with the rice seeds in the gel coating layer.

FIG. 2 shows a method of enclosing air bubbles together with seeds within the gel coating layer.

In the figure, a nozzle main body 1 has a plunger insertion hole 2 passing through it in the vertical direction, and a cylindrical cutting plunger 3 is inserted into the plunger insertion hole 2.

The plunger insertion hole 2 has a tapered valve seat 4 at its lower end that becomes smaller in diameter toward the bottom, and has gel channels 5 on the left and right sides.

The cutting plunger 3 is a pressing member such as a spring (not shown).
The valve 3a at the lower end closes the valve seat 4, but if the gel filled in the gel flow path 5 and the plunger insertion hole 2 is pressurized, the valve 3a will be cut off. A pressure receiving part 3b provided on the plunger 3 is pressurized and rises, so that the valve 3a opens the valve seat 4.

Cylinders (not shown) are disposed at the right and left ends of the nozzle body 1, and the piston 6°7 of the cylinder connects to the gel flow path 5.
It is inserted into the interior of the housing so that it can move forward and backward (see Figure 2 (a)).

When the piston 6 enters the gel flow path 5 from this state, the cutting plunger 3 pressurized by the pressure receiving part 3a rises, the valve 3a opens the valve seat 4, and the gel 8 flows out (Fig. 2). (See (b)).

Next, when the piston 6 retreats, the gel flow path 5 becomes negative pressure, gel is replenished from the reed valve (not shown), the cutting plunger 3 descends, and the valve 3a closes the valve seat 4. The gel 8 flowing out from the valve seat 4 forms a film whose center hangs down due to its own weight, but does not fall due to its own weight due to its adhesive force.

At this time, seeds 9 are dropped and supplied from above (see FIG. 2(c)).

Next, the piston 7 enters the gel flow path 5, and again the valve 3a
is separated from the valve seat 4, the gel 8 flows out, and the seeds 9 become air bubbles 10.
and is sealed in the gel 8 (see FIG. 2(d)).

Then, when the piston 7 retreats and the valve 3a closes the valve seat again, the hanging gel 8 cannot support the increased weight and falls into the curing liquid in the curing liquid tank below. It becomes spheroidized due to surface tension (see Figure 2 (e)).

In this way, as shown in FIG. 1, a gel coating layer 8 of the seeds 9 with the air bubbles 10 sealed is completed.

Larger seeds require more oxygen during germination, but the oxygen supply period required for seed rice germination is the period after the seed rice germinates until the first true leaf emerges.

Therefore, it is sufficient to encapsulate the required amount of air bubbles in the gel along with the rice seeds, but when coated seeds containing air bubbles are sown in rice fields, a problem arises in that they float on water.

In order to submerge the coated seeds with air bubbles in the paddy soil, the problem can be solved by increasing the apparent specific gravity of the coated seeds to a value greater than 1. (2) Add specific gravity increasing material such as fine sand at the conventional coating gel concentration.

There are the above two methods.

Next, a specific gravity increase test when a specific gravity increasing material is added is shown below.

A specific gravity increasing test in which a specific gravity increasing material was added is shown below.

Substances that can be used as specific gravity increasing materials must be harmless to plants and soil, and should, in principle, be for agricultural use.

Under these conditions, the following specific gravity materials were tested.

fa) Solid fertilizer pulverized product (bl) Cultivated river sand pulverized product (C) Hydroball pulverized product for hydroculture (d) Kanumagami pulverized product tel Akadama soil pulverized product or higher density increasing material is used as a specific gravity increasing material if it is water soluble. However, the water solubility and specific gravity of each specific gravity increasing material are shown below.

From the above results, both can be used as specific gravity materials, but when adding crushed solid fertilizer, the degree of salt excavation inside the covering material increases, so it is not suitable because there is a high possibility that the seeds will suffer from salt damage. Not.

Furthermore, if calcium is present in the specific gravity increasing material, there is a risk that the gel will harden, but the gel resistance of each specific gravity increasing material was as follows.

Explanation of symbols in the table A: Particles form and are not uniformly dispersed in the gel B: Particles solidify little by little and are dispersed in the gel C: Fine particles remain dispersed in the gel Tests above From the results, it was confirmed that solid fertilizers cannot be used as specific gravity increasing materials, but other materials can be used as specific gravity increasing materials and the apparent specific gravity can be made larger than 1.

However, if a large amount of the specific gravity increasing material is added, the binding force of the gel decreases, so it is necessary to increase the concentration of the gel to some extent instead of relying solely on the addition of the specific gravity increasing material.

By the method described above, by adjusting the specific gravity of the gel coating layer, it has become possible to directly sow cultivation in flooded soil using gel-coated seeds containing air bubbles.

〔effect〕

The present invention has the following effects.

(1) It has become possible to mechanically sow rice seeds by coating them with gel in a spherical shape with approximately the same volume.

(2) Since the seed rice is coated with a gel together with air bubbles, the germination rate of the seeds can be increased, and since oxygen generating agents such as calcium peroxide are not used, the soil will not be contaminated.

(3) Since the seed rice is coated with a gel containing chemicals, preliminary measures and coating can be carried out at the same time.

(4) The gel coating agent can have an apparent specific gravity greater than 1 by mixing a specific gravity increasing material, and coated seeds with air bubbles can be reliably cultivated in flooded soil.

[Brief explanation of drawings]

1 and 2 show examples of the present invention, FIG. 1 is a cross-sectional view of gel-coated seeds having air bubbles, and FIG. 2 is an explanatory view of gel-coating processing of air bubbles and seeds. 8... Gel, 9... Seed, 10... Air bubble. Patent applicant Yazaki Sogyo Co., Ltd. Figure 1 (a) (d) (book) Figure

Claims (1)

[Claims] Rice seeds are covered with a hollow spherical gel film layer having approximately the same volume as the air bubbles, and the components and concentration of the gel material forming the gel film layer are adjusted so that the apparent specific gravity of the entire gel film layer is 1 or more. A covered seed for direct sowing of rice in flooded soil, characterized by the following.