JPS6181733A - Acidic liquid carrier for rock wool culture medium - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Industrial Application Fields This invention provides a method for using alkaline rock wool as an artificial medium for raising seedlings or cultivating, in cooperation with watering applied to the rock wool. In order to make the pH of the rock wool medium suitable for raising seedlings and cultivating plants,
This invention relates to an acidic liquid carrier for rock wool culture medium.

<Prior art> Rock wool produced in Japan is mainly made from blast furnace slag, and therefore contains as much as 40% alkaline content, and its pH is generally 8 or higher, with many reaching 10 or higher. On the other hand, rice seedling growing medium has a pH of 4.5~
An acidity of 5.5 is considered to be the optimum condition. Therefore, in order to use strongly alkaline rock wool as a rice seedling growing medium, by covering the 11-seed layer of rock wool with acidic soil with a pH of 4 to 5, watering from above the covering soil can cover the whole medium. It is possible to make it moderately acidic, and the acidic covering soil can be obtained from natural soil.
JP-A-58-141726 discloses the use of fumaric acid, malic acid, nitrofumic acid, which has been adjusted to be acidic with an acidifying agent.

On the other hand, superabsorbent resins made of acrylic polymers and superabsorbent resins made by graft polymerizing acrylonitrile onto starch are already commercially available, and the latter can be found in the 29th issue of Industrial Materials published by Nikkan Kogyo Shimbun. No. 8 P, 48-5
It is explained in 1.

<Problem to be solved by the invention> When considering the agricultural uses of rock wool, it ranges from the above-mentioned rice seedlings and sprouts, which last about a week, to the relatively long-term use, which takes about eight weeks, such as tomato seedlings. In addition to being used as a medium for growing seedlings for a short period of time, it can also be used for a much longer period of time, from 6 months to 3.4 years, for growing vegetables and flowers, or as a water retention bed for potted plants. It has several uses. Among these, when used for a relatively short period of time, consideration for allowing the acidifying agent to gradually dissolve into the irrigation water is not particularly important. However, when it comes to long-term use, the situation is completely different, and its sustainability is of great concern, preferably over the entire period of use. If this is not possible, it would be desirable for the grower to be able to easily and safely replenish or replace the product midway through the process to achieve a sustained effect for as long as possible.

In addition, when sowing seeds, planting seedlings, or cultivating them in pots, it is important to avoid acidifying the seeds or plants so that they may come into direct contact with the acidifying agent and cause growth problems. It is desirable that the acidity of the agent is such that it does not cause any damage even if it comes into direct contact with the roots.

An object of the present invention is to provide an acidic liquid carrier for rock wool culture medium that can easily meet the above-mentioned demands.

Means for Solving the Problems This invention uses a substance that is more than neutral or alkaline and has excellent liquid retention properties. In addition to activated carbon and charcoal, super absorbent resins made by grafting acrylonitrile onto acrylic polymers and starch can be used. The l)H of activated carbon made from coconut shell charcoal exhibits an alkalinity of 8 to 9 at actual measurement sites, and super absorbent resin "Sunwet I-1-1000" made of starch polyacrylate (Sanyo Chemical Industries, Ltd.) Co., Ltd.) has a pH of 7.5, which is weakly alkaline.

Powdered or granular superabsorbent resins are preferably used by holding them in a sandwich between substrates such as paper or nonwoven fabrics, by mixing them into substrates, or by coating them. The paper or nonwoven fabric in this case may be water-soluble if necessary.

A large amount of liquid can be retained by immersing the above-mentioned substance with excellent liquid retention in the acidifying agent liquid or by spraying the liquid. As acidifying agents, sulfuric acid, nitric acid, etc. are dangerous to handle, and there are problems such as reactions with fertilizers and calcium, magnesium, etc. in the culture medium, and adverse effects on roots due to accumulation of salts in the culture medium. Easy to obtain even for ordinary farmers,
Vinegar and its special-strength vinegar are suitable because they are inexpensive, harmless to human and livestock crops, and have no fear of publicity.

Commercially available vinegar has a pH of about 2.6 pro-i. Such acidifying agents are more alkaline than neutral] ゛They react with substances that have excellent direct liquid retention properties, thereby raising the pH to 311-5.
The retention acidic liquid is less than 5. The reason why the l)H of the retained acidic liquid is specified as 3.5 or more and 5 or less: Mountain 1 is that if the pH is too low, it is impossible to use a strong acid with a pH lower than this because it will dissolve the rock wool fiber itself. On the other hand, if the pH is too high, it will lack the ability to neutralize the alkaline Rockwool medium, and considering the effect that the pH of the medium has on the roots of vegetables, it is recommended to use a pH of 3. This is because 5th place can be said to be the limit. Generally, 1) l-1 of body fluid of crops is about 4.2.

The acidic liquid held in the substance with excellent water retention will not be easily released even if it is washed with water for a long time, in other words, it is exposed to irrigation water. As for its retention effect, the amount of water required per plant in vegetable cultivation is generally 12.72 for strawberries, 65.6 for melon, 119.1 for eggplant, and 164 for tomato.
．． 5λ, 165.8 for green pepper, 173 for J21 cucumber
．． In contrast to the required surface moisture of 4°C (5λ degrees), an acidic liquid is still retained within the substance, and the acidic waves dissolve into the irrigation water, changing the pH of the alkaline Rockwool culture medium. pl-14.5 to 5.5, pl-1 for vegetables
It can be adjusted to a suitable range of 5 to 7.

<Example> First, a case will be described in which activated carbon made from coconut shell charcoal is used as a material with excellent liquid retention properties.

When this activated carbon (pH 8, s>64 g) was soaked in Mizkan vinegar (pH 2, 6) for 1 hour and 409 was absorbed, the activated carbon had a pH of 4.3.

Next, in the seedling box, 2cm thick x 28cm long x 53cm long.
A layer of rock wool (pH 7,8>) was spread, and activated carbon 275Q adsorbed with the above vinegar was sprinkled thinly on the top surface, and then tap water (1) Hf 3.8) was sprinkled over the top.

On the other hand, as a comparative example, the same amount of mitscanic acid was directly added to rock wool without using vinegar-adsorbing activated carbon (30
pl-14,3) was prepared after being left for a minute, and tap water was sprinkled over it.

The results are shown in the table below.

Irrigation m Inventive product Comparative example - and - Rock wool discharge 1 pH of wastewater IIHJ of rock wool, rlHO of water (7, 8)
<4.3) -1,55
5,36,94,3 4,95,3G,9 4.74.5
4,8 5.1 +3.9
5,910 4.9
5,2 7,0 6,220
4.9 5.2 7.1
6,535 5.5
5,3 7,2 6.840
5.3 5.4 7
．． 3 6J50 5.4
5.4 7,2 6,855
5.4 5.4
- -GOS, 3 5.5
- - When the required amount of water (m) per plant is applied from above, the product of the present invention sufficiently achieves the desired purpose, whereas the comparative example cannot be expected to have any such effect. Recognize.

Next, regarding the case of super-absorbent resin, a white powdery super-absorbent resin "Sunwet IM-1000J (trade name)" made of starch polyacrylate manufactured by Sanyo Kasei ■ was mixed with a vinegar solution (acidity 4.2%). , pH 2,6) for 1 hour, it was found that 825g of vinegar was absorbed per 10g of resin.Next, the resin (p)l that absorbed this vinegar was
'4.0) As in the previous example, 800Q was sprinkled thinly on the rock wool and watered over it. The results are shown in the table below.

Irrigation (λ) Rock wool pH grade -201 once yo-〇 (7,8)
-1,54,34 34,44 4,54,34 104,54,1 204,54,2 354, G 4.2 40 4.7 4.35054
．． 8 55 5.6 5.460
5.6 5.580
6 6.21
00 G, 4
6.3150 6.3
6.2 The method of using the acidic liquid carrier according to the present invention will be explained with reference to the embodiment shown in the drawings. FIG. An example in which an acidic liquid carrier A @ a decoy shape is formed on this seeding layer is shown in Fig. 2, in which a film 4 is stretched on a shelf frame 3 for pot cultivation, and a rock wool molded material 2 is placed inside the film 4 as a water-retaining bed. This is an example of potted plant production in which a sheet 5 in which acidic liquid carrier A is held sandwich-like between two nonwoven fabrics is placed on top of the sheet. In addition, FIG. 3 shows a black polyethylene film bag 6 in which granular rock wool cotton 2a and an acidic liquid carrier are mixed together and sealed, and a hole 7 for planting is formed on the top surface of the bag and a hole 7 is formed on the side surface of the bag. This is an example of so-called bag cultivation with a cut 8 for drainage, and the grown seedlings 9 are planted in alignment with the planting holes 7. If the seedlings 9 are grown in a Rockwool medium, a right porous bag 10 containing the acidic liquid carrier A is placed on top of the seedlings 9, and the water 111 is poured into this acidic liquid. ti! through carrier A! ! Very good. Also, please take a look.
The acidic liquid carrier A may be placed in the container 1 and the irrigation water must be supplied through the container 11. The example shown in FIG. 4 differs from that shown in FIG. 3 in that a rock wool molding 2 is used. Of course, when molding the rock wool molded article 2, the acidic liquid carrier A may be dispersed and held.

<Effects of the Invention> This invention provides that when rock wool is used as an artificial medium for raising seedlings or cultivating, the pH of the medium is adjusted during the seedling cultivation period.
It is extremely superior in that it can be adjusted to an appropriate value by 1 m, and even if the roots come into direct contact, it will not cause the same damage.

[Brief explanation of drawings]

FIG. 1 to FIG. 4 are explanatory diagrams showing examples of use of the acidic liquid carrier for rock wool culture medium according to the present invention. 2... Rock wool molded article, 2a... Rock wool cotton, A... Acidic liquid carrier.

Claims (1)

[Claims] 1. An acidifying agent is adsorbed and reacted with a substance that is neutral or alkaline and has excellent liquid retention properties, and a large amount of acidic liquid with a pH of 3.5 or more and less than 5 is retained in the substance, and the retained acidity is An acidic liquid carrier for rock wool culture medium, characterized in that the liquid can be gradually eluted by irrigation.