JPS6251082B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a method for raising rice seedlings using a seedling box.
In particular, this is a rice seedling raising method that uses aluminum-deposited synthetic resin sheets during germination.

[Conventional technology] Rice seedlings for mechanical planting are used in boxed seedlings as young and medium-sized seedlings, and each seedling grown in the box is grown at a height that will not be submerged in water during rice transplantation. In order to suit the workability of the plant and make it easy to plant, the plant must have good root connections and be uniform throughout. Therefore, appropriate seedling-raising methods are required for each of young and medium-sized seedlings from sowing to growing seedlings, but in particular, during the 3-4 day germination period after sowing, it is necessary to keep the temperature at around 30℃ to prevent initial germination. It is necessary to manage budding to strengthen the momentum.

The conventional methods for heating during the budding stage are as follows:
For raising seedlings in the cold season (raised from April to early May) at low temperatures, there is a method of loading seedling boxes into a temperature-adjustable budding warmer and allowing them to germinate, and for raising seedlings in the warm season when temperatures are higher (5 When raising seedlings (from early March to June), seedling boxes were stacked outdoors, covered tightly with vinyl sheets, and allowed to germinate using sunlight. After germination, the stacked seedling boxes for both were taken out, placed side by side on a flat field, covered with cheesecloth in a tunnel shape, and seedlings were raised while controlling hardening of the seedlings. In addition, instead of covering with a vinyl sheet, some methods have been used to cover the seedling box with cheesecloth from the beginning, or to cover the seedling box with a film or newspaper made by dissolving aluminum paste into a synthetic resin film.

[Problems to be solved by the invention] With the conventional method of stacking seedling boxes like this, there is no risk of applying too high a temperature when raising seedlings in the cold season due to automatic adjustment of heating, and the time required for germination is almost instant. They can be produced at a constant rate, and there is little problem of spreading after sprouting. However, when growing seedlings in warm seasons, they are tightly covered with a vinyl sheet and heated by sunlight, making it difficult to adjust the temperature. The temperature reaches an abnormally high temperature of 40 degrees Celsius, which can inhibit germination and even cause buds to wither and die.In addition, humans rely on human eyes to determine when to lay the seedling box flat for greening, so the appearance of buds may be too high. Those who are concerned about the length of growth, take a long time to pile up, make the buds elongate, tend to lose the balance between the above-ground parts and roots, and end up being difficult to handle with a rice transplanter, i.e., weak and defective rice that tends to cause drooping leaves The drawback was that it was more likely to become seedlings or poorly grown seedlings with poor rooting. In addition, cheesecloth covering is good after germination, but before germination it has no water retention properties, so the bed soil tends to dry out and requires irrigation, which is a troublesome problem.

Aluminum paste-containing film has good water-retention properties in the bed soil and heat retention at night, and has a good warming effect during the day, but on the other hand, there is a risk of abnormally high temperatures due to sunlight, and newspapers tend to dry out the bed soil and retain moisture. However, there is an annoying problem. In the seed and seedling raising method, the first focus on seedling management is the management at the time of emergence, and farmers often fail due to mistakes or omissions in sprouting management, and careful attention is required. At present, efforts are being made to improve the quality of seedlings, and a new technology that can stably grow healthy seedlings has been long-awaited.

[Means for Solving the Problems] In order to solve the above-mentioned conventional problems, the present invention provides a method for germinating rice by stacking seedling boxes and heating them by sealing them with vinyl sheets as in the past. By placing the seedling boxes side by side on a flat surface from the beginning of seedling raising and using an aluminum vapor-deposited synthetic resin sheet to cover them, we can prevent abnormally high temperatures caused by solar heating, have a good heat retention effect at night, and further improve the bed soil. The purpose of the present invention is to provide a method for raising rice seedlings using an aluminum vapor-deposited synthetic resin sheet that prevents rice from drying out and allows suitable germination under conditions of good moisture retention.

This invention is a rice seedling-raising method in which seedlings are raised using seedling boxes containing rice seeds in the soil. After sprouting, remove the aluminum-deposited synthetic resin sheet,
This is a method of raising rice seedlings using aluminum vapor-deposited synthetic resin sheets, which is characterized by carrying out normal greening and hardening of rice seedlings.

The characteristics of the rice seedling raising method of this invention are that conventionally stacked seedling boxes are placed side by side on a flat field, and instead of using a vinyl sheet as a covering material, an aluminum vapor-deposited synthetic resin sheet is used, and the seedling boxes are directly flattened and covered. It is to be used until budding.

Aluminum vapor-deposited synthetic resin sheet is a well-known product made by vapor-depositing aluminum onto the surface of polyester, polyethylene, polypropylene, etc. film to form a thin film, and has been used as an agricultural covering film for growing flowers, fruits, vegetables, etc. Although,
In this case, the method of use is to make holes in the film only for the seedlings and spread it directly on the soil surface of the nursery. During the day, the sunlight reflected on the metal-deposited surface of the aluminum-deposited synthetic resin film is used to protect flowers, fruits, and vegetables. This method differs from the method of the present invention in that it utilizes the effect of contact with the leaves of the present invention. In this invention, it has been discovered that an excellent seedling-raising effect can be obtained by using an aluminum-deposited synthetic resin sheet in a seedling-raising box during the raising of rice seedlings until the seedlings germinate. Note that films containing aluminum paste have poor reflectance and the material itself is subject to high temperatures due to solar radiation, so there is a high risk of abnormal high temperatures when used flat, and care must be taken when covering tunnels.

By the way, in the flat seedling raising method, an attempt was initially made to cover the seedlings with a paper material sheet made of newspaper, etc., but there were problems with paper material sheets such as newspaper as they dried out and the method of retaining moisture was cumbersome. Therefore, in this invention, the conventional drawbacks are overcome by using an aluminum vapor-deposited synthetic resin sheet.

Next, it will be explained with reference to the drawings. Fig. 1 shows the conventional method of stacking seedling-raising, and is a conceptual diagram showing seedling-raising boxes stacked outdoors and covered with vinyl sheets. First, wetting layer 4 was applied on top of the layer, and finally, the entire surface was covered with vinyl sheet 5. With this conventional method, it is difficult to adjust the temperature due to solar heating, and on days with strong solar radiation, the inside of the cover can reach abnormally high temperatures of 40°C, which could impede germination.

Fig. 2 is a conceptual diagram showing the method of raising seedlings laid flat according to the present invention, which eliminates the above-mentioned drawbacks. It is covered with a resin sheet 10.

In addition, in both the conventional method shown in FIG. 1 and the method of the present invention shown in FIG. 2, after germination, the seeds are covered with cheesecloth tunnels and greening and curing are performed.

[Example] The following points are listed as the conditions that should be met as a covering material during the sprouting period in the flat seedling raising method.
As a result of actually using it for raising seedlings, the aluminum-deposited synthetic resin sheet of the present invention is superior to vinyl sheets, aluminum paste-containing films, newspapers, and the like.

(1) The bed soil should be sufficiently dry-proof (moisture-retentive) until germination.

Humidifying the bed soil during the germination period impedes ventilation into the bed soil, lowers the bed temperature, prevents the elongation of the seed roots, which are the first roots, and weakens subsequent growth, so it is important to increase seedling height quickly. When raising young seedlings that require good root support, watering during the budding stage is particularly undesirable as it tends to over-moisten the bed soil. (In warm regions, seedlings can grow naturally in the open, but as the bed soil dries easily, daily watering is required and the seedlings usually grow small and have difficulty gaining height.) Even if the average temperature is maintained at 24℃ during the germination period in late March), it is possible to maintain the moisture content of the bed soil for about 5 days without watering, and if the bed soil is sufficiently irrigated, one box of regular soil (60cm long) can be maintained without watering. , 30cm wide seedling box with 2cm bed soil thickness)
The water absorption amount of the bed soil is 1.5, and the limit soil water content that can be absorbed by sprouting seedlings is 0.3, so 1
The condition is that the daily evaporation amount can be kept below 0.25. Aluminum vapor-deposited synthetic resin sheets and vinyl sheets are airtight and have very low moisture permeability, so they are suitable because they can maintain dryness for about 7 days, but paper raw material sheets have a large amount of evaporation and can only maintain dryness for about 2 days. Therefore, irrigation is required during the process, which is not desirable.

(2) Maintain a temperature range suitable for sprouting and never allow abnormally high temperatures.

During the warm-season seedling raising period (early May to June), the temperature is already at the temperature at which seedlings can grow, so keeping the temperature warm is sufficient to increase the force of germination; in fact, there is no problem. Abnormally high temperature due to overheating. Even if the temperature is not so high, as the summer solstice approaches, the solar radiation is becoming stronger, so in good weather the temperature inside the cover will rise significantly.
It exhausts the seedlings and sometimes causes buds to die. The temperature inside the box is within the appropriate range of 32℃ during the day and at night.
The temperature should preferably be around 18°C, and the temperature should not rise above 37°C even on a good day, and the temperature should never rise above 40°C. The temperature increase limit of the covering material should be around 5°C when the air temperature is 30°C, and it should also have a high heat retention effect with little heat radiation at night when the temperature drops. The main factors that cause solar temperature rise in coating materials are solar heat ray transmittance and moisture permeability due to evaporative heat dissipation.Aluminum vapor-deposited synthetic resin sheets had a maximum temperature of 34℃, while vinyl sheets and aluminum paste-containing films did not. When used, the moisture permeability is extremely small, so even if heat ray transmission is suppressed, the temperature will rise abnormally, and the temperature inside the coating will exceed 40℃, and if you are not careful, it can reach nearly 50℃, which is advantageous for preventing soil from drying out. But it's unsuitable. In addition, although the paper raw material sheet did not have the problem of high temperature damage, it was inferior in terms of drying resistance due to its high moisture permeability.

(3) Light blocking rate must be approximately 80%.

Not only for germination, but also for increasing seedling height.
Since a certain amount of bud elongation is necessary, budding in the dark is appropriate, but if you leave the buds in complete darkness for a while, they tend to bud into long buds, and preliminary greening is required to adjust to the light and prevent bleaching. It is preferable to germinate under low light with a shading rate of about 80% without any growth, which also improves seedling quality. In this respect, the aluminum vapor-deposited synthetic resin sheet of the present invention has a light shielding rate of about 80%, which is preferable, the vinyl sheet has almost no light shielding property, and the newspaper, on the other hand, has a light shielding rate of 90% or more, which is not preferable.

(4) Able to cover the seedling box directly with a flat layer.

Flat covering costs less than tunnel-shaped covering (230 cm width is required when covering a 2-row flat seedling box with tunnel covering, but 160 cm wide with flat covering).
This is desirable because it does not take much time to cover, but the temperature increase due to direct light absorption of the coating material itself is small, the sprouted buds will not burn due to contact heat even if laid flat, and the buds will not loosen even in the rain. A condition for use as a flat material is that it does not press down on the soil surface. In this respect, vinyl sheets can be directly spread over seedling boxes, but the heat absorption from direct light causes a large temperature rise, and the contact heat from the buds causes seedling burn, and newspapers get wet and stretch when it rains. As a result, the tension loosens and presses the surface of the soil, and the sheet tears, which are both unsuitable.However, the aluminum vapor-deposited synthetic resin sheet of the present invention is superior because it does not have these drawbacks.

[Effects of the Invention] This invention is a method for raising seedlings as described above, and the advantages of using an aluminum vapor-deposited synthetic resin sheet as a covering material for raising rice seedlings on a flat surface are summarized as follows.

(1) The aluminum vapor-deposited synthetic resin sheet has a mirror-like glossy surface, so it reflects a lot of solar heat rays and has great heat shielding properties, and it also has low heat radiation at night, giving it good heat retention. With a light shielding rate of 80%, the temperature increase will be about 4 degrees Celsius when the air temperature is 30 degrees Celsius, and even if the temperature reaches 32 degrees Celsius in the daytime, the temperature inside the covered box will not exceed 37 degrees Celsius, so there is a risk of abnormally high temperatures. The growing temperature is maintained even at night. In particular, as the nighttime temperature decreases, the bed temperature can be raised relatively to encourage root development and the growth of healthy seedlings. Therefore, it exhibits excellent seedling-raising effects as a covering material during the budding stage of rice, regardless of whether it is warm or cold.

(2) Even if you create some ventilation holes without completely sealing it using a simple flattening method, the soil moisture will be retained for more than 5 days, there will be no need for watering during budding, and there will be no harm from harmful gases. There is no oxygen deficiency and there is no problem with sprouting.

(3) Since the heat absorption of the material itself is small, there is no need to worry about burning the seedlings when it comes in contact with it, and since the sheet has tension, there is no need to worry about it loosening and pressing against the bed soil even if it is laid flat directly on the seedling box.

(4) The coating can be used for about 4 days during the budding period, so it can be used for 3 seasons, has low depreciation costs, is easy to use in general, and can also be used for conventional purposes such as using reflected light and preventing pilus disease. .

The seedling raising method of this invention not only avoids abnormally high temperatures during the rice budding stage and overhanging budding, which are the main causes of failure in stacking seedling raising, but also facilitates root formation when the bed temperature is higher than the outside air temperature at night, similar to natural conditions. The conditions are favorable, and even if the initial bud growth is small, later seedling growth is improved, and there is no need for labor to load seedling boxes, so anyone can stably and labor-savingly raise healthy seedlings, which will be desired in the future. It can pave the way for sowing and raising seedlings and contribute to improving rice cultivation techniques.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram showing a conventional stacked covering of seedling growing boxes, and FIG. 2 is a conceptual diagram showing a flat covering according to the present invention. (Explanation of symbols), 1...earth, 2...stand, 3...
... Seedling raising box, 4... Wet mat, 5... Vinyl sheet, 10... Aluminum vapor deposited synthetic resin sheet, 11...
…Ridge.

Claims (1)

[Claims] 1 In a rice seedling raising method in which seedlings are raised using seedling boxes with rice seeds prepared in the soil, the seedling boxes with rice seeds prepared in the soil are placed side by side on a flat field, and an aluminum vapor-deposited synthetic resin sheet is directly spread and covered to induce germination. A method for raising rice seedlings using an aluminum vapor-deposited synthetic resin sheet, characterized in that after the aluminum vapor-deposited synthetic resin sheet is removed, the rice seedlings are subsequently greened and hardened.