JPH01312932A - Seedling raising mat for paddy rice plant - Google Patents

Abstract

PURPOSE:To obtain a seedling raising mat having eliminated problems of fertilizer concentration during seedling raising of paddy rice plant and having sterilizing action by using rock wool carrying isobutylidenediurea as a culture medium. CONSTITUTION:A seedling raising mat comprising rock wool carrying isobutylidenediurea as a culture medium. The rock wool is a matted material comprising a molded article of rectangular parallelepiped in a felt state, an elastic board state or further a slab state, obtained by using a resin binder and a matted material having about 50-80kg/m<3> density is usually used. Isobutylidenediurea is obtained by condensing one molecule of isobutylaldehyde with two molecules of urea and powder of granules having <=2.0mm particle diameter are used. An organic acid having properties of forming a chelate with iron as an oxidizing agent to maintain a culture medium at an acidic side of about pH5 suitable for growth of seedling of paddy rice plant and iron are supported on rock wool so that phosphorus can be well absorbed in seedling of paddy rice plant.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a seedling growing mat for growing seedlings used in rice cultivation.

[Conventional technology]

In recent years, mechanical transplantation has become extremely popular in wet rice cultivation, with the aim of saving labor during rice transplantation, and more than 95% of the area is planted using mechanical transplantation. This is the reality.

In the above-mentioned mechanical transplant cultivation, seedlings grown in a nursery box are usually transplanted by machine, and after applying fertilizer on the floor of the nursery box, the seeds are scattered, and the surface is covered with soil. Seedlings grown with N water are used.

Recently, a seedling growing mat using a rock wool rectangular molded body as a medium instead of the bed soil has been proposed. Seedling raising mats that are coated with or soaked with water-soluble solid fertilizers are beginning to be used.

[Problem to be solved by the invention]

By the way, the seedling mat for paddy rice using the rock wool rectangular shaped body as a medium is irrigated throughout the seedling growing period and is constantly immersed in water.
ammonium sulfate supported on the medium made of rock wool;
Water-soluble solid fertilizers such as phosphoric acid 1 lime have the disadvantage that most of them are leached into water in the early stage of seedling raising.

In other words, when growing seedlings using the conventional rock wool-based seedling mat for paddy rice, the concentration of water-soluble fertilizers such as ammonium sulfate and monopotassium phosphate becomes relatively low within 1 to 5 days from the start of seedling raising. germination, uneven germination,
It may cause poor germination, such as 1.
From about day 0 onwards, the fertilizer concentration will drop markedly, leading to a state of insufficient fertilizer, which may lead to insufficient plant height, stunted growth, etc.

In particular, the problem of water-soluble fertilizer concentration when growing seedlings using the rice seedling mats mentioned above is noticeable in cold regions, and the application of top-dress fertilizer is strongly advised to solve this problem. Since this requires time and effort, it is difficult to completely eliminate the problems of water-soluble fertilizers by applying additional fertilizer.

Also, the aforementioned Rockwu? A seedling raising mat using a rectangular molded body as a medium has iron sulfate carried as an acidifying agent in rock wool as a medium to adjust the pH of the rock wool to an acidic side suitable for raising paddy rice seedlings. Since iron sulfate, which is an acidifying agent, has the property of forming insoluble iron phosphate with phosphoric acid, which is one of the fertilizer components, phosphoric acid is not absorbed sufficiently by rice seedlings. It also has the disadvantage that it cannot be carried out.

In contrast, the invention of the youngest brother 1 solves the problem of fertilizer concentration during the raising of paddy rice seedlings using a seedling raising mat, and also provides a seedling raising mat for paddy rice that also has a bactericidal effect against Fusarium fungi and Rhizopus fungi. In addition, the invention of the youngest brother 2 solves the problem of fertilizer concentration during the raising of paddy rice seedlings using a seedling mat, and also has a bactericidal effect against Fusarium and Rhizopus bacteria, and furthermore, the pH of rock wool is To provide a seedling-raising mat for paddy rice, which prevents phosphoric acid fertilizer from being insufficiently utilized when iron sulfate is used to adjust the acidity to the acid side suitable for raising paddy rice seedlings.

[Means to solve the problem]

In the rice seedling growing mat invented by the youngest brother 1, the culture medium in the rice seedling growing mat is composed of rock wool that supports isobutylidene diurea.

In addition, the seedling mat for paddy rice according to the invention of youngest brother 2 has a medium in which the mat contains isobutylidene diurea, an organic acid having the property of forming a chelate with iron, and iron sulfate. It is made up of supporting rock wool.

The rock wool used as a medium in the seedling mat for paddy rice of the present invention having the above-mentioned structure can be formed into a felt shape or an elastic board shape obtained using a resin binder, or a rectangular shape such as a slab shape. It is a mat-like material made of bodies, and a mat-like material having a density of about 50 to 80 kg/rrl is usually used.

The isobutylidene diurea supported on the rock wool medium is imbutylidene diurea, which is a condensation product of one molecule of isobutyraldehyde and two molecules of urea, and is obtained by the following reaction formula, with a particle size of 2 .0
One granule of powder is used.

The isobutylidene diurea granules are slightly soluble in water, and after being dissolved in water, they are relatively quickly hydrolyzed and decomposed into urea and imptyraldehyde. The urea produced by this process acts as a nitrogen fertilizer.

In addition, particle size 2. Dissolution of isobutylidene diurea consisting of 1 grain of powder below Osu+ in water at room temperature is 200M water.
1 and isobutylidene diurea 10! According to a dissolution test in which water was added to water and fresh water was replaced once a day,
Approximately 5-15% in 5 days, approximately 15-35% in 10 days, 2
Approximately 25-55% in 0 days, approximately 35-65% in 30 days,
It has been confirmed that it is about 45-75% in 40 days.

Further, the isobutylidene diurea, as described above,
After being dissolved in water, it undergoes hydrolysis relatively quickly to produce urea, and the byproduct of this process, isobutyraldehyde, has a bacteriostatic effect against Fusarium and Rhizopus bacteria. In particular, when the culture medium is maintained at an acidic pH of about 5, a more excellent effect of preventing the onset of disease in seedlings caused by the Fusarium fungi and Rhizopus fungi can be obtained.

The amount of isobutylidene diurea supported on the medium made of rock wool is, for example, about 10 days after the fertilizer effect of the conventional water-soluble solid fertilizer has been utilized by about the 10th day from the start of seedling raising. It is sufficient that the amount is sufficient to compensate for subsequent fertilizer shortage, and it is usually preferable that 20 to 40% of the conventional water-soluble solid nitrogen fertilizer be replaced and supported by the isobutylidene diurea.

The isobutylidene diurea granules may be supported on rock wool during the process of collecting, compressing, and molding rock wool to obtain a culture medium using rock wool.
Alternatively, it can be easily supported on rock wool obtained by accumulating, compressing, and molding rock wool, for example, by press-fitting, spraying an aqueous dispersion, drying, or the like.

In addition, the ``organic acid that has the property of forming a chelate with iron'' used in the invention of Youngest Brother 2 is used to adjust the pH of rock wool, which is a culture medium, to an acidic side suitable for raising paddy rice seedlings. Tear is a substance that forms a chelate with iron sulfate, for example, citric acid, fumaric acid, malic acid, etc.
It is preferable to replace a part of the conventional iron sulfate, which is supported so as to be maintained at about H5, with the organic acid.

〔Example〕

Hereinafter, the specific structure of the seedling growing mat for paddy rice of the present invention is as follows:
An explanation will be given based on an example.

Examples/Comparative Examples A rock wool rectangular molded body with a length of 60 cm, a width of 30 mm, and a thickness of 1.8 cm was treated with isobutylidene diurea, which is a powder with a particle size of 0.3 mm or less, and the following
The seeds of 160.
7 (6,000 to 8,000 grains) of rice seeds (Sasaninki) were sown almost evenly, covered with soil, and kept at 32°C for 2 days.

Continue to take them outdoors from the next day, and continue to water them once or twice a day to prevent the covered soil from drying out. , P2
The test results regarding the O5 content and the presence or absence of Fusarium and Rhizopus are also listed in Table 1.

In addition, the number of germination, dry weight, fullness,
The values for plant height and P2O5 content are comparative values when the conventional rice seedling mat shown in Comparative Example 1 is taken as 100, and the test results for the presence of Fusarium and Rhizopus are as follows. , which is the result confirmed by a microscope. [Operations and effects of the invention] The rice seedling growing mat of the invention of the youngest brother 1 is characterized in that the medium in the rice seedling growing mat is composed of rock wool that supports isobutylidene diurea. It is something that
Further, in the rice seedling growing mat invented by the youngest brother 2, the medium in the rice seedling growing mat contains isobutylidene diurea, an organic acid that has the property of forming a chelate with iron, and iron sulfate. It is made up of supporting rock wool.

Therefore, in the seedling mats for paddy rice of the present invention having the above-mentioned configuration, isobutylidene diurea supported on the medium made of rock wool is imbutylidene diurea, which is a condensation product of one molecule of isobutyraldehyde and two molecules of urea. It is a granular form of urea, and it is only slightly soluble in water. Furthermore, after being dissolved in water, it undergoes hydrolysis relatively quickly and decomposes into urea and imbutyraldehyde, so it cannot be hydrolyzed. The urea produced by this process acts as a slow-release nitrogen fertilizer in rice seedling mats that are kept moist.

Therefore, in the seedling-raising mats for paddy rice of the present invention, the fertilizer effect of the conventional water-soluble solid fertilizer can be utilized until about the 10th day from the start of seedling-raising, and after the 10th day, the Since the fertilizer effect of butylidene diurea can be utilized, it is possible to avoid the harmful effects of ammonium sulfate on the cultivation of seedlings on conventional rock wool seedling mats as a medium, that is, around 1 to 5 days from the start of seedling cultivation.

Uneven germination and poor germination caused by the tendency for the concentration of water-soluble fertilizers such as phosphoric acid 1 lime to become high.

It also eliminates the disadvantages such as insufficient plant height and poor growth caused by insufficient fertilizer, where the concentration of fertilizer decreases significantly after about the 10th day.

In addition, as described above, the isobutylidene diurea supported on the medium made of rock wool in the paddy rice seedling growing mat of the sphagnum moss invention is imbutylidene diurea, which is a condensation product of one molecule of isobutyraldehyde and two molecules of urea. It is a granular form of urea that is slightly soluble in water, and after being dissolved in water, it undergoes hydrolysis relatively quickly and has a bacteriostatic effect against Fusarium and Rhizopus bacteria. Since it generates isobutyraldehyde, it has the effect of inhibiting the onset of disease in seedlings caused by the aforementioned Fusarium bacteria and Rhizopus bacteria.
When maintained on the acidic side of about 5, a more excellent effect of preventing the onset of disease in seedlings caused by the Fusarium fungi and Rhizopus fungi can be obtained.

In addition, in the seedling mat for paddy rice invented by the youngest brother 2,
A medium made of rock wool has a pH suitable for growing rice seedlings.
As an acidifying agent to maintain the acidity level of about 5, iron sulfate and an organic acid that has the property of forming a chelate with iron are supported, so in conventional rice seedling growing mats, When iron sulfate is used, insoluble iron phosphate is produced between it and phosphoric acid, which is one of the fertilizer components, and this prevents the absorption of phosphoric acid by rice seedlings. Absorption is achieved and healthy growth of paddy rice seedlings is achieved.

Patent applicant: Nittobo Co., Ltd.

Claims (2)

[Claims] (1) A seedling mat for paddy rice, characterized by using rock wool supporting isobutylidene diurea as a medium. (2) A seedling mat for paddy rice, characterized in that the culture medium is rock wool that supports isobutylidene diurea, an organic acid that has the property of forming a chelate with iron, and iron sulfate.