JPH0429904A - Plant growth-promotive preparation - Google Patents

Abstract

PURPOSE:To obtain a preparation having a plant growth-promotive effects for a long period of time by microencapsulation of a core material, an active ingredient consisting of dichlorodiisopropyl ether with a sheathing material capable of regulating the optimal vaporization rate of the core material according to the environment. CONSTITUTION:The objective preparation can be obtained by microencapsulation of (A) a core material, an active ingredient consisting of dichlorodiisopropyl ether (DCIP) with (B) a sheathing material consisting of a polymer (e.g. polyamide, polyester, polyurea, polyurethane) at the weight ratio of A/B=pref. (1:0.03) to (1:0.3). The microencapsulation is carried out through, e.g. interfacial polymerization, in-sutu process. The present preparation is sustained release microcapsules 1-50mum in mean particle size and 0.1-5mum in sheath thickness, being effective for the long-term growth promotion of spinach, strawberry, rice, green tea, tobacco, tangerine, garden plants, etc., and its dosage being 5g/m2 in terms of the amount of DCIP.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention is directed to dichlor, which has the effect of promoting plant growth, but has a high volatilization rate and therefore is difficult to stably use as a plant growth promoter. Diisopropyl ether (
Hereinafter abbreviated as DCIP. ) can be easily used as a growth promoter by adjusting its volatilization rate.

[Conventional technology]

Conventionally, the active ingredient DCIP has been put into practical use as a nematocide in Japan because it has high activity as a nematocidal ingredient. At the same time, it was known that DCIP often has a growth promoting effect on plants. However, the vapor pressure of DCIP is 0.58 mmHg/20℃
Because the drug has a relatively high level of drug efficacy, its active ingredients disappear quickly and its growth promoting effect is not long-lasting.There is currently a strong desire to eliminate these drawbacks and stabilize the durability of the drug's efficacy. be.

Furthermore, emulsion or kneading with inorganic minerals and surfactants,
In general formulations such as wettable powders and granules obtained by impregnation, controlling the volatilization rate is difficult and practically impossible.

On the other hand, by microcapsulating the active ingredient as a growth promoter, it is possible to release its action in a sustained manner to maintain its efficacy and to prevent adverse effects on organisms other than the target. Until now, no method has been disclosed for encapsulating the active ingredient DCIP as it is as a core material.

[Problem that the invention seeks to solve]

The object of the present invention is to provide a sustained-release microencapsulated preparation containing DCIP, which has a microcapsule wall that can freely adjust the optimum volatilization rate according to various environments, and has a long-term plant growth promoting effect. It is provided by.

[Means for solving problems]

In the microencapsulation of DCIP in the present invention, the core material is DCIP alone or a mixture containing DCIP, and the outer wall material has a sustained release property that allows adjustment of the volatilization rate of DCIP, and also reduces its medicinal efficacy. A method is used to micro-encapsulate DCIP from a single outer wall. In the microcapsule production technology, widely known interfacial polymerization method, in-5iLu method, phase separation method, in-liquid curing coating method (orifice method), in-liquid drying method, spray-granulation method, etc. can be used. The interfacial polymerization method and the n-5 itu method are particularly useful because they enable microencapsulation of the desired DCIP effectively and economically.

Particularly preferred as a material that satisfies the above objectives are polymeric materials formed using reactive materials such as monomers or low molecular weight prepolymers; examples of such polymeric materials include polyamide resins, polyester resins, polyurea resins, polyurethane resin, urea resin, guanamine resin,
Examples include melamine resin and composite materials thereof.

In the present invention, there is no particular limitation on the preferred ratio of the core substance containing DCIP to the wall material, but in consideration of economic efficiency, it is preferable that the wall material does not have a direct plant growth promoting effect. However, the microcapsule wall material of the present invention must sufficiently retain the encapsulated liquid DCIP and at the same time protect the encapsulated material, which naturally limits the lower limit of the amount of wall material to be used relative to the core material. From the above, the preferred weight ratio of the core material and wall material is ].1 to ]:0. OI,
More preferably, the ratio is 1:0.3 to 1:0.03.

In addition, in order to adjust the volatilization rate of DCIP and maintain the effect of promoting plant growth over a long period of time, the preferred average particle size of microcapsules containing DCIP as a core material is 100 μm.
0.1μm or more, film thickness 10μm or less 0.01μm
More preferably, the film thickness is 508 m or less and 1 μm or more, and the film thickness is 5 μm or less and 0.1 μm or more.

The sustained-release microencapsulated preparation containing DCIP of the present invention can be applied to plants, especially vegetables such as spinach and strawberries, horticultural crops such as flowers, common crops such as rice and grass, occasional crops such as tea and tobacco, mandarin oranges, and apples. When long-term growth promotion is required for fruit crops such as
It is also possible to use P in an amount of 1 to 20 g/rd, preferably 5 g/rd, by spraying, soil treatment, etc.

Therefore, the sustained-release microencapsulated preparation containing DCIP of the present invention can be used in a wide range of applications, including an aqueous dispersion of microcapsules, a powder, or a formulation or molding of the powder. make it available for use.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples, and the method for obtaining the intended sustained-release microencapsulated plant growth promoting preparation containing DCIP is not necessarily limited to these Examples. Throughout this specification, all temperatures are 90°C and parts and percentages are by weight unless otherwise specified.

Example 1 DCIP (135 parts) to polymethylene polyphenylisocyanate rMR-200J (trade name, ()
After adding and dissolving 2% polyvinyl alcohol rPVA-21 (produced by Honpolyurethane Co., Ltd.) (31.6 parts),
In addition to 7J (trade name, manufactured by Kuraray Co., Ltd.) solution (300 parts), emulsification was carried out using a biomixer (manufactured by Nippon Seiki Co., Ltd.) so that the particle size of the emulsion was 20 μm. While slowly stirring the resulting emulsion, an aqueous solution of diethylenetriamine (3 parts) dissolved in water (40 parts) was gradually added, and the mixture was stirred at room temperature for about 20 hours until the reaction was sufficiently controlled. This was carried out to obtain a sustained release polyurea wall microcapsule dispersion containing DCIP.

Example 2 Terephthalic acid chloride (10 parts) was added to DCIP (135 parts).
After adding and dissolving 3% polyvinyl alcohol rPVA-217J (trade name, manufactured by Kuraray Co., Ltd.) solution (
300 parts) and emulsified in a biomixer so that the particle size of the emulsion was 20 μm.

While slowly stirring the resulting emulsion, add water (70 parts).
An aqueous solution in which ethylenediamine (3,4 parts) and soda ash (6 parts) were dissolved in advance was gradually added to the solution, and stirring was continued at room temperature for about 20 hours to ensure a sufficient reaction.
A sustained-release polyamide-walled microcapsule dispersion containing the following was obtained.

Example 3 Urea (240 g) was added to 37% formalin solution (488.5 g).
After dissolving the solution and adjusting the pH to 8.0 with triethanolamine, the mixture was heated and stirred at 70°C for 1 hour. Water (1
00 parts) to prepare a urea-formaldehyde prepolymer.

After adjusting the pH of the prepolymer solution (80 parts) to 4.2 with a 10% citric acid aqueous solution, DCIP (65 parts) was added while emulsifying with a biomixer, and the pH of this emulsion was adjusted to 10. After adjusting the temperature to 3.5% with an aqueous solution of citric acid, the temperature was gradually raised and stirred at 40 to 45°C for 40 minutes. Warm water (50 parts) was further added, and the mixture was stirred for 3 hours and cooled to obtain a urea-formalin resin-walled microcapsule dispersion containing DCIP.

Comparative Example 1 DCIP (25 parts) in 2% polyvinyl alcohol rPVA-217J (trade name, manufactured by Kuraray Co., Ltd.) solution (100 parts)
added.

Comparative Example 2 To DCIP (85 parts), Tsurupol 2613B (trade name, manufactured by Toho Chemical Co., Ltd.) (5 parts) and white kerosene (10 parts) were added and mixed and stirred to prepare a homogeneous sample.

<Method for Measuring the Amount of DCIP in a Capsule> A predetermined amount of the microcapsule dispersion containing DCIP obtained in Examples 1 to 3 was collected, and acetone was added.

Extract DCIP in an ultrasonic bath and filter it with a membrane filter.
After filtration, the filtrate was subjected to analysis.

<Sustained release evaluation method> Regarding the samples of the DCIP dispersion liquids used in Examples 1 to 3 and Comparative Examples 1 and 2, approximately 0.8 g in terms of DCIP
/ 100cIil was spread uniformly over the entire Petri dish. Each sample was left standing in an atmosphere at 25° C., and after a certain period of time, the residual rate of DCIP was measured by the method described above.

Sustained-release properties of DCIP-containing microcapsules (DCIP residual rate %) <Test examples> Test example 1 DCIP sustained-release microcapsule formulations prepared based on Examples 1, 2, and 3 and those prepared based on Comparative Example 1゜2. The growth promoting effects of the DCIP formulations on spinach were compared.

An amount equivalent to 4 kg, i/loa of each DCIP preparation was applied to the center of a 1/2000a pot filled with soil at a depth of about 15 cm. After that, 15 spinach seeds were sown per pot, and thinned out at the germination stage, resulting in 7 seeds per pot.
Aligned with stocks. The test was repeated three times.

All plants were pulled out during the harvest period, and leaf length, aboveground composition, and root weight were measured.

Results Test Example 2 The growth promoting effect on strawberries of the DCIP sustained release microcapsule preparations prepared based on Examples 1, 2, and 3 and the DCIP preparation prepared based on Comparative Example 1.2 was compared.

Each of the above preparations is added to the accelerated strawberry house at DCIP equivalent of 8k.
The soil was mixed to a concentration of g/lOa, and 7 days later, the plants were planted using a conventional method. The number of test plants was 20 per plot and repeated twice, and the yields of each plot about 4 months after planting were totaled to determine the average yield per plant.

result Out applicant Niss Day Co., Ltd. φ varnish biotic 1]

Claims (1)

[Claims] A microencapsulated plant growth material comprising dichlordiisopropyl ether as an active ingredient, the active ingredient as a core material, and a wall material formed around the core material to allow sustained release of the core material. Accelerator formulation.