JPH057427A - Ridging for raising plant and production thereof - Google Patents

Abstract

PURPOSE:To obtain ridging for raising plants providing plug seedlings having shape retention, impact resistance, etc., by uniformly blending ridging on the market with a binder such as agar sol solution and binding in a specific state. CONSTITUTION:Ridging on the market is uniformly blended with a binder comprising agar sol solution, bentonite and/or starch, parent material particles constituting ridging are mutually bonded with the binder while leaving pore void required for plant growth to give the objective ridging supplying plug seedlings having shape retention, impact resistance, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soil suitable for producing seedlings of leaf vegetables, fruit vegetables, flowers, etc., and for potted cultivation of flowers, bonsai trees, etc.

[0002]

2. Description of the Related Art Soil for raising seedlings and potted culture is prepared by mixing various soil materials with natural soil such as organic materials and inorganic materials to adjust the solid phase, liquid phase and vapor phase balance of the soil.
It is used by adding a fertilizer component suitable for the plant to be cultivated. Natural soil is categorized in various ways according to the base material, sedimentation mode, and properties.

For example, in classification by soil properties, heavy clay, plant soil, plant loam soil, loam soil and the like are classified according to clay content. Materials such as pest moss, bark compost, lignite, chaffed charcoal, vegetative charcoal powder, etc. as organic materials in such natural soil as organic materials, and as inorganic materials,
Perlite, vermiculite, rockwool, zeolite, etc. are added for cultivation. Furthermore, in some cases, a method of adding a polyvinyl alcohol-based or polyacrylylamide-based polymer substance to agglomerate the soil particles to solidify them is also carried out.

In any case, in order to be suitable for plant physiology, various soil materials are adjusted by paying attention to the three-phase state of solid phase, liquid phase, and gas phase as soil soil requirements, and water retention, water permeability, In addition to balancing the air permeability, the initial mixing of solid fertilizer and the operations such as irrigation and replenishment of liquid fertilizer during cultivation are taken into consideration so that the soil characteristics suitable for the purpose can be obtained. .

Taking the growth of plug seedlings using such a soil as an example, conventionally, a cell 92 having a thick plate 91 made of plastic foam or the like as shown in FIG. Using a seedling raising tray 90 formed by molding a large number of seeds, the cell 92 is filled with soil and fertilizer for seeding and growing. Then, when the seedling 95 becomes an adult seedling and the raising of the seedling is completed, the stem and leaves of the seedling are grasped with fingers, pulled out upward, and transplanted or planted in a field.

[0006] The criteria for completing the growth of such plug seedlings are that the roots extend vertically and horizontally in the voids of the soil and hold the soil firmly, that is, the so-called root pot is sufficiently formed, and the foliage is used. The root weight occupies a sufficient proportion of the total weight of the plant (root weight ratio), and it is easy to remove from the cell without damaging the root by grasping the forage of the seedling with fingers. Things are considered to be important indicators.

[0007]

[Problems] With the progress of aging of farmers in recent years, automatic planting of seedlings has been demanded for vegetables and flowers as well as for rice transplanters. In order to meet such a demand, there is a transplanter that uses so-called paper seedlings, which are grown using a paper tray having cells that are composed of paper frames, but the paper seedlings have poor seedling quality and The paper frame that forms the boundary is mechanically cut and the root pot is wrapped with paper, so-called paper pot seedlings are planted in the field, so it takes time for the paper pot to collapse and the roots to grow. It has a drawback that it takes a lot of time and is not lively. This is a major cause of not spreading in vegetable seedlings where the quality of seedlings and the quality of initial growth greatly affect the yield. On the other hand, in the case of plug seedlings without such defects,
It is essential to pull out the seedlings from the seedling raising tray with fingers, and a satisfactory automatic transplanter has not been put to practical use.

The present inventor has developed an automatic seedling planting machine for transplanting or planting plug seedlings, which is disclosed in Japanese Patent Laid-Open No. 2-1.
It was disclosed in Japanese Patent Publication No. 77823. As shown in FIG. 2, the planting machine A selectively selects the seedlings from the self-propelled vehicle 1 and the seedling raising tray 2 on which the plug seedlings to be planted have been raised by the vacuum pressure in the seedling transport pipe 303. The seedling extracting device 3 for extracting the seedlings below the cell, the seedling transporting device 4 for forcibly transporting the extracted seedlings to a predetermined position by a pressure gradient generated by vacuum pressure, and the seedlings that have been transported. Should be dropped to erect and a planting groove is formed, and a planting device 5 composed of a soil gathering device and the like for performing soil planting by soiling from both sides of the erect seedling.

The seedling raising tray 2 used in the planting machine A has a two-stage separation type construction as shown in FIG. 3, and the upper stage side forms a tray body 201 for accommodating the soil. On the lower side, a bottom body 202 that fits with the bottom of the tray body 201 is formed. The tray body 201 is made up of a large number of cells 203 each having a tapered hole having a draft that expands downward, and the bottom body 202 is a cell 203.
It has a fitting projection 206 for closing the open bottom of the. Reference numeral 207 is a water drain hole provided in the protrusion 206.
Reference numeral 207 is an outlet for excess water when supplying water to the seedlings. The seedling raising tray 2 in FIG. 2 shows a state in which the bottom body 202 is removed and attached to the planting machine A at the time of transplantation.

As described above, the conventional soil is premised on sandwiching the foliage of the seedling with fingers and pulling it out upwards. Therefore, if sufficient root pot is not formed, the soil in the cell is When pulling it away from the wall surface, the force applied to the foliage causes root cutting, which causes the seedlings to come off from the soil and spoils the seedlings. Length, large voids do not hinder the growth of roots, low specific gravity so that unnecessary weight is not added at the time of extraction, binding force with the cell wall surface so that the extraction force from the cell is small Is required. In the present situation, commercially available soil is generally formed of peat moss, carbon powder, and other base material particles having almost no shape-retaining property so as to satisfy such conditions.

Therefore, when the conventional seedlings are used and the seedlings raised by the seedling raising cell 2 are planted by the aforesaid planting machine, first, at the stage of seedling removal, the cells 203 are removed.
The lower half of the medium soil collapsed, exposing the roots,
There is a drawback that it causes root cutting, and further, due to the impact when it falls from the seedling transport pipe that bends in an S shape to the ridge, the collapse further progresses and the survival is greatly delayed, or after planting. There was a defect that it died and the planting itself became impossible.

Also, depending on the type of seedling, such as asparagus, there are many main roots and few side roots, so that the root pot formation may be immature even at the proper planting period. Depending on the cultivation conditions, seedlings may be planted in a state where root pots are not yet formed, but in the conventional soil, such seedlings may be mechanically transplanted by hand, of course. However, transplanting is impossible because the soil and roots are separated or the roots are cut off when the seedlings are pulled out.

On the other hand, in recent years, the production of seedlings has become a specialization due to the division of labor from the self-cultivation of farmers. This is
It has the advantages of cost reduction due to large scale and the production of uniform and healthy seedlings, which leads to reduction of the burden on farmers. However, such production of seedlings inevitably requires long-distance transportation of seedlings, and accordingly, ensuring the quality of seedlings during transportation is extremely important. On the other hand, the conventional soil has poor water retention, and there is a risk that the seedlings wither and die during long-distance transportation.

Further, in the conventional plug seedlings, it is an important indicator of the completion of the seedling raising that the root pots are sufficiently formed as described above. It is necessary to develop enough roots to compensate for the transpiration of water from, and thus even if a root pot is formed,
When the leaf stem grows so as to exceed the water absorption of the root,
Since the survival rate is poor, in order to prevent such overgrowth of leaf stems, use a well-permeable medium to supply water and nutrients,
It is necessary to pay attention to sunshine hours, temperature, etc. to raise seedlings, which requires skill and experience.

[0015]

The object of the present invention is to eliminate the various problems of the soil as described above, but in particular, in terms of the root weight ratio, the formation of root pots, etc., there is no difference compared to the conventional soil. In addition, the first main purpose is to provide a cultivating soil having a sufficient shape-retaining property that does not damage the plant when used in the automatic planting machine for plug seedlings as described above. A second main object of the present invention is to provide a plug seedling medium that can be planted by the aforementioned automatic planting machine regardless of the growth stage of the seedlings, as long as the natural conditions are satisfied. .

[0016]

The present invention has been earnestly studied in order to achieve such an object, and then, in the soil of various compositions which are generally used at present, agar gel, starch or a binder is used.
It has been found that the soil obtained by combining the base material particles with bentonite has sufficient characteristics for the purpose of the present application, and has completed the present invention. The gist of the present invention is that at least a part of the particles of the base material constituting the soil, or between all the base material particles, leaving pores necessary for root growth of the plant to be grown, and harmless to plant physiology. The soil for plant growth is characterized in that it is bound to each other by a binder to acquire shape retention. Further, the present invention, when subjected to appropriate treatment in the soil, while ensuring a sufficient porosity, a binder capable of binding between the base material particles constituting the soil, the soil in advance, It is in the soil for growing plants, which is mixed with the base material.
The present invention also includes a method for producing a soil, which comprises treating the soil base material with a binder to bond the base materials to each other with a binder leaving sufficient pores. The details will be described below.

The binder used in the present invention needs to be harmless to the plant physiology itself, and can grow a healthy seedling having a sufficient root weight ratio without growing as a seedling. is important. The present inventor achieves the object of the present invention by using, as a binder, one or more kinds selected from agar, starch, bentonite, and boclay after trial and error in pursuit of such materials. I found that I could do it.

Agar is an ideal binder because it has excellent water retention, shape retention and ability to adsorb nutrients, but bentonite and boclay can also fully achieve the object of the present application, and starch also has a good shape retention. , A little inferior to agar, but enough
The object of the present application can be achieved. In particular, bentonite, boclays and starch are superior to agar in that they are inexpensive. First, although various types of agar are commercially available, the minimum concentration at which an agar sol solution gels is about 0.1.
% Aqueous solution, and the concentration of the agar solution and the gel strength (jelly strength) produced by gelling the agar solution are in a substantially proportional relationship.

When used as a binder in the present invention, in the case of kaku agar or thread agar, which has a relatively weak gel strength,
In the case of powder agar having a strength of about 1 to 3.5%, or a relatively high gel strength, it is desirable to use an agar sol aqueous solution of about 0.7 to 1.7%, but a concentration of about 1% is most preferable. The agar sol liquid is heated and dissolved by adding a predetermined amount of agar to water, and then using this as a soil for cultivating natural soil, peat moss, bark compost, charcoal powder, etc. In a state of being filled in, it is injected into this and diffused uniformly, and the excess agar gel solution is drained from the lower hole of the cell to ensure sufficient pores for root development after cooling. Then, the soil matrix particles are bonded.

When the concentration of the agar sol solution increases beyond the above range, the viscosity of the sol solution increases and it becomes difficult to uniformly diffuse and permeate into the soil. On the other hand, when the concentration of the agar sol exceeds the above range, the binding strength becomes conspicuous, and the shape retaining property intended by the present application is impaired.

[0021] The soil currently on the market has an apparent specific gravity (bulk specific gravity), a porosity, a porosity, depending on the properties of the base material constituting the soil.
Equilibrium moisture content in the atmosphere is different. Commercial soil is
Depending on the combination of the base materials, the solid phase rate, liquid phase rate (moisture rate), and gas phase rate (air rate) are adjusted to obtain the desired water permeability, water retention, and air permeability. Is at least 20
It is necessary to secure a gas phase rate of at least%. Although depending on the composition of the base material, the water content is generally about 20 to 30%, and the porosity (gas phase ratio + liquid phase ratio) is in the range of about 50 to 80%.
For example, the porosity of soil having an aggregate structure that is optimal for plant growth is about 60%, and the water content is about 30%.

In order to bond the base material particles of such a general commercial soil with an agar gel, the agar sol liquid needs to penetrate into the gas phase. As a rough guideline for permeation, it is preferable that the water content of the medium in which the agar sol solution is injected is about 60% or more. In the unlikely event that more water than necessary is poured into the soil, the vapor phase becomes full, and even if the soil becomes fluid, if the agar sol solution is within the above-mentioned predetermined concentration range, an extra agar sol solution pot, A predetermined bond strength is generated in the soil and the gas phase is secured by the runoff from the cell or the like, the evaporation of the water from the soil, etc., so that there is no practical problem.

When the agar sol gels and binds the soil particles, the concentration of the agar sol solution used in the present application is
It is about 0.7 to 3.5%, and if the agar weight and the amount of water to be evaporated are ignored, the weight of the agar gel remaining in the soil will all contribute to the water content. When the agar sol solution is prepared, the fertilizer necessary for the growth of the seedlings is dissolved in water in advance, so that the fertilizer can be effectively used without being washed away by watering the seedlings.

Another method of using agar as a binder is to mix it with powdered water-adjusted medium,
This agar powder mixed culture medium is filled in a suitable container, a heat-resistant planting pot, a heat-resistant seedling raising tray, etc., and then heated at a gelling concentration or higher, preferably 100 ° C. or higher, depending on the water content in the culture medium. There is a method of making a sol liquid and cooling it to gel.

The concentration of the sol solution may be set within the above range depending on the weight of agar to be added and the water content of the soil. According to this method, sterilization of the soil itself is carried out at the same time in the sol-forming step of agar, so that sterilization treatment with a chemical or the like is unnecessary. The agar powder used in this case may contain impurities such as seaweed, and need not be pure agar.

As such a binder to be mixed with the soil in a granular state in advance, swelling clay such as bo clay and bentonite can be used in addition to agar powder. As the swelling clay, bentonite is particularly excellent in shape retention, and depending on the composition of the base material of the soil, 5-80% of the weight of the soil is used.
It is used in a granular form by mixing it with the soil. By pouring an appropriate amount of water into the bentonite-containing soil and adjusting the water content, the bentonite swells to form a caking property, bonds between the soil base material particles, and reaches practical strength.

As described above, the commercially available soil generally used has a remarkably different bulk specific gravity depending on the composition of the base material. Therefore, it is more practical to determine the practical standard of the blending amount to obtain the desired shape-retaining property and to obtain the cultivating soil environment suitable for the growth of seedlings by the swelling clay such as bentonite. is there. The present inventor, for various soils having different base material compositions, after repeating trial and error, put a room temperature dry soil containing swelling clay in a seedling growing container such as a cell or a seedling of a seedling raising tray, Water is gently irrigated from the surface, and when the penetration of water into the soil is apparently stopped,
When the compounding amount allows penetration to a depth of around mm,
It has been found that practically no problems occur in practically all kinds of soils and in most leaf vegetables and fruit vegetables. However, if the permeability is less than this, root development may be inhibited.

Alternatives to agar gels, bentonites and voclays are starch and its gel solutions. Like the bentonite, the starch may be used by mixing it with a commercially available soil in a powdered state and injecting water, or, like an agar sol, heating an aqueous starch solution of about 10 to 30% to gel it. Injected into the soil in the same way as the agar sol solution,
They may be mixed, and as the water content decreases due to evaporation of water or the like, caking occurs, and when the water content falls below a certain limit, a binding strength with practical strength is generated. Therefore, the types of plants to be grown and the drying of the soil at the time of planting, etc.
is important. Bonding power is better than bentonite and agar gel.
Somewhat inferior. Further, starch does not necessarily have to be pure starch, and old rice etc. can be used as a starch source.

[0029]

[Effect] The soil reinforced by the binding agent of the present application is
For example, in the case of agar gel, the gel strength is 300-1200g
/ Cm ² firmly bonds between the base material particles, and thus has sufficient shape retention, and a sufficient gas phase ratio is secured between the base material particles, and the binder itself Has excellent water retention and has the effect of automatically adjusting the water content in the soil, making it an ideal environment for plant root growth.

The plug seedling (lettuce) produced by the soil of the present application is sucked by vacuum pressure to be detached from the seedling raising tray, and is bent into an S shape while maintaining a perfect circle with a length of about 2.5 meters. It was transported by suction pressure in a soft vinyl chloride pipe and dropped on cultivated soil, but the soil collapsed due to the detachment from the cell, the root pot lost its shape during transportation, the collapse due to the drop impact, and the root damage at all. I was not able to admit.

This means that if a seedling raising tray capable of extracting seedlings downward is used by using the soil of the present application, the seedlings are still seedlings according to the conventional standard regardless of the growing condition of the root pot. Even in this condition, it is possible to plant, so it is possible to transplant at a timely condition such as climate or other conditions.
In addition to improving survival, it is possible to obtain the effects of streamlining agricultural work and shortening the production period of seedlings.

The cultivating soil of the present invention, which uses, for example, an agar gel containing 1% of dried agar as a binder, if the agar weight is neglected, the gel is all water, and this gel is used as a binder. Since it is lightly covered, the plant roots growing here can utilize water in a state where a sufficient gas phase is secured. Even if the water in the gel is lost, when the water is irrigated or the nutrient solution is replenished, the swelling property of the gel ensures that it efficiently absorbs nutrients and water, and the fertilizer effect is better than that of conventional soil. Extremely high. On the other hand, on the contrary, since the release of water from the gel becomes slow, against moisture transpiration due to fluctuations in temperature and humidity and the amount of solar radiation (particularly remarkable for summer seedlings),
It has a great buffering effect and can produce seedlings of stable quality all year round. This action is as a binder, bentonite,
It is commonly observed when starch is used, though to a different degree. This means that while the need for long-distance transportation of seedlings increases, the maximum period for which seedlings can be left without management such as water supply is 3 to 7 days compared to the conventional maximum of 3 to 9 days.
It can be extended to days and has the effect of significantly improving the shelf life characteristics of seedlings.

[0033]

EXAMPLES In the present example, what was conventionally used as an example of the soil was a commercially available soil for plug seedlings (hereinafter abbreviated as plug soil), the material composition of which was 50% clay, 20% peat moss, and 10 vermiculite. %, Husk smoky charcoal 10
%, Pumice stone 5% and charcoal powder 5% (all are volume percentages). Using this cultivated soil as it was, lettuce seedlings were raised according to a conventional method and used as a control example. On the other hand, at the same time, 1% agar sol liquid obtained by using powder agar (manufactured by Ina Foods Co., Ltd.) was added to this conventional soil, and after uniformly dispersing, the soil was left to cool and gel ( , Agar gel culture soil) and bentonite in an amount of 30% by weight of the plug culture soil and uniformly mixed (hereinafter referred to as bentonite culture soil) were used to raise lettuce seedlings and the results were compared.

In the seedling raising test, a cylindrical cell having a diameter of 20 mm and an effective depth of 30 mm and having a 1% draft downward as shown in FIG. Using 9 seedling raising trays arranged at the lattice points, allocate 3 each for plug soil, agar gel soil, bentonite soil, and put each soil in each,
After sufficiently watering, lettuce coating seeds were sown on the seeds, and the seeds were covered with plug soil. All work was done carefully by hand. After sowing, put them in the nursery room, supply water, supplement nutrients, etc. under the same conditions for all three.
A method of spraying from a distance of 30 cm above the tray by a spraying device was adopted.

The results showed that the lettuce seedlings grown on the agar gel medium showed the most remarkable growth (average plant height of about 8 cm), and the next was bentonite soil (about 7 cm of the same), which were grown for 7 days and 5 days, respectively. A growth-promoting effect that was apparent in appearance was recognized as compared with lettuce seedlings (about 5 cm in the same size) grown in plug soil for a day. At the bottom opening of the cell of the seedling raising tray in which these lettuce seedlings are stored, hit the upper end of the cylindrical pipe as a forced seedling transport pipe with the inside of the pipe set to a vacuum degree of 500 mm of water and an air volume of 0.78 m ² / min. When the seedlings were detached from the cell and contacted with each other, the plug soil was immediately disintegrated from the bottom, and the soil was disintegrated about 1/3 to be removed and the hair root was exposed in the form of filaments. , The detachment of the seedling from the cell occurred. Also, cutting of hair roots was observed together with the soil. On the other hand, in the case of the agar gel soil and the bentonite soil, such a phenomenon did not occur at all. However, the agar gel took longer to desorb than the bentonite.

Also, in order to test the effect against drop impact, seedlings grown in each soil were treated with 1m, 1.5m, 2m,
From a height of 2.5 m or 3 m, the impact resistance was examined by allowing it to fall freely on the surface of soil that had been stepped on. For plug soil,
In the drop test from 1 m, the root pot collapsed at a rate of 50%, and none of them survived the drop test of 2 m. On the other hand, 2m for bentonite soil and agar gel soil
About 15% of the root pots were slightly deformed in the drop test, but even in the drop test of 3 m, the deformation rate was almost unchanged, and the amount of particles separated from the root pot was small. At the increasing level, there was no change that substantially hindered planting.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an example of a conventional seedling raising tray for raising plug seedlings.

FIG. 2 is an explanatory view showing a planting machine for automatically planting plug seedlings.

FIG. 3 is an explanatory view showing an example of a seedling raising tray for pulling out plug seedlings downward.

[Explanation of symbols]

A seedling automatic planting machine 2 Nursery tray 4 seedling forced transport pipe 5 planting equipment 203 cells

Claims (8)

[Claims] 1. A part or all of the base material particles constituting the soil are bonded to each other by a binder and have a shape-retaining property, leaving pores necessary for the growth of plant roots. Characteristic soil for growing plants. 2. The soil as claimed in claim 1, wherein the binder is one or more of agar gel, bentonite and starch. 3. The culture medium according to claim 2, wherein the agar gel contains a plant fertilizer component. 4. A soil for cultivating plants, wherein the soil is mixed with a binder for binding the base materials constituting the soil to give shape retention. 5. The soil as claimed in claim 4, wherein the binder comprises one or more of agar, a substance containing an agar component, starch, a substance containing starch and bentonite. 6. The agar sol solution is injected into a culture soil filled in a plant growing container such as a pot or a seedling raising container and uniformly dispersed, and then the agar sol liquid is gelated to transform the base material particles of the culture soil into an agar gel. A method for producing a soil for growing plants, which is characterized in that 7. As an agar sol liquid, 0.7% to 3.5%
7. The method according to claim 6, wherein the agar sol aqueous solution is used. 8. The method according to claim 7, wherein the plant fertilizer component is dissolved in the agar sol aqueous solution.