JP2986753B2 - Pest control agent for fish habitat - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a pesticidal composition containing chitosan for a fish habitat.

[0002]

2. Description of the Related Art Chitosan is obtained by deacetylating chitin contained in the shells of shrimp and crabs and the cell wall of microorganisms. Since it is obtained from natural products, it is environmentally friendly. Its usefulness has been found in various uses such as an agent and a soil conditioner.

[0003] Above all, plant cultivation is promoted by promoting rooting, improving rooting survival and increasing nutrient absorption, and increasing plant activity to prevent the occurrence of pests. It has the function of promoting
JP-39207 discloses a plant pest control agent obtained by mixing acetic acid with chitosan, for soft rot of vegetables, spring baldness of lawn,
It is described that it is effective against plant diseases such as large patch, leaf blight, brown patch, sycamore, bacterial blight of rice, and scab of fruit trees.

[0004]

However, chitosan has a fish poisoning effect. For example, when a drug containing this chitosan is applied to an area such as a river or a pond where fish inhabit, chitosan has a fish toxic effect on fish. It can act to kill a large number of fish and affect ecosystems.

It is an object of the present invention to provide a plant pest control agent for fish habitats which does not cause any harm to fish even when applied to areas such as rivers and ponds where fish live. .

[0006]

Means for Solving the Problems In view of the above problems, the present inventors have conducted intensive studies on detoxifying the fish toxicity of chitosan, and found that pulverized coal and / or montmorillonite group minerals were added to chitosan. It has been found that the compounded compound can control plant pests without affecting fish and the like at all, and completed the present invention.

That is, the present invention relates to a pesticidal agent for fish habitats containing chitosan, pulverized coal and / or montmorillonite group minerals.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The chitosan of the present invention is obtained by first obtaining chitin from the shell of shrimp, crab and the like, and then hydrolyzing and deacetylating the obtained chitin.

[0009] The above-mentioned chitin is composed of shells of shrimp and crab,
It is obtained by deproteinization and decalcification. The deproteinization treatment is performed by, for example, treating shells such as shrimp and crab in an alkaline solution such as a 3 to 5% aqueous sodium hydroxide solution at about 80 to 100 ° C. for about 2 to 4 hours to obtain shrimp and crab. Extract and remove proteins and the like from the shell of
6 to 5% at room temperature in an aqueous acid solution
By treating for 24 hours, calcium carbonate is removed from shells such as shrimp and crab.

[0010] The chitin thus obtained is hydrolyzed and deacetylated to obtain chitosan used in the present invention.

The hydrolysis and deacetylation are preferably carried out simultaneously in an acid or alkali solution at a predetermined temperature for a predetermined time at a predetermined temperature.

In this case, conditions are appropriately selected depending on the molecular weight of the obtained chitosan and the degree of deacetylation.

In the present invention, chitosan has a molecular weight of 7
0000-20,000, especially 40,000-5000
It is preferably about 0, and the degree of deacetylation is preferably about 75 to 100%, preferably 75 to 90%. If the molecular weight of chitosan exceeds 70,000, the effect of inhibiting the growth of plant pests may not be sufficiently exhibited, while if the molecular weight is lower than 20,000 by hydrolysis, the productivity is reduced. If the degree of deacetylation of chitosan is lower than 70%, it may not be solubilized in water.

Suitable conditions for the above-mentioned molecular weight and degree of deacetylation are, for example, 40 to 50.
The treatment may be performed at 100 to 115 ° C. for about 2 to 4 hours using an aqueous alkali solution such as an aqueous sodium hydroxide solution.

The chitosan thus obtained, having the desired molecular weight and the desired degree of deacetylation, is mostly insoluble in water. It is preferable to prepare the solution so as to have a concentration of 10 to 10% by weight, and then add an acid to solubilize the chitosan in water to obtain chitosan as an aqueous solution.

As the acid used in this case, any known acid may be used as long as it can solubilize chitosan in water. For example, formic acid, acetic acid, propionic acid, butyric acid, citric acid, apple Organic acids such as acids, malonic acid, succinic acid, tartaric acid, and lactic acid, and acids such as inorganic acids such as hydrochloric acid, sulfuric acid, and phosphoric acid can be exemplified. Of these, organic acids are preferred, and in particular, lactic acid which is inexpensive and has no odor is more preferred. These acids may be used alone or in combination of two or more kinds.
The amount is 60 to 140 parts by weight, preferably 80 to 120 parts by weight, based on 00 parts by weight.

The aqueous solution of chitosan thus obtained is adjusted to a pH of 4 to 4 using an aqueous solution of sodium hydroxide or the like.
It is preferable to keep the number at 6.

The chitosan aqueous solution of the present invention only needs to be soluble in water in appearance, and, for example, a transparent colloidal state is also included in the chitosan aqueous solution of the present invention.

Known additives such as preservatives, insecticides, insect repellents and the like may be added.

Examples of such preservatives include 3-bromo-2,3-diiodo-2-propenylethyl carbonate, 3-iodo-2-propynylbutylcarbamate, 2,3,3-triiodoallyl alcohol, parachlorophenyl Organic iodo-based preservatives such as -3-iodopropargyl-formal, for example, benzimidazole or benzothiazole-based preservatives such as 2- (4-thiazolyl) benzimidazole and 2-thiocyanomethylthiobenzothiazole, for example 1- ( 2- (2 ', 4'
-Dichlorophenyl) -1,3-dioxolan-2-yl-methyl) -1H-1,2,4-triazole, 1-
(2- (2 ', 4'-dichlorophenyl) -4-propyl-1,3-dioxolan-2-yl-methyl) -1H
Triazoles such as -1,2,4-triazole, α- (2- (4-chlorophenyl) -ethyl) -α- (1,1-dimethylethyl) -1H-1,2,4-triazole-1-ethanol Preservatives and the like.

Examples of the insecticide include organophosphorus insecticides such as phoxime, chlorpyrifos, fenitrothion, pyridafenthion, propetanphos and fenthion, such as cyfluthulin, permethrin,
Pyrethroid insecticides such as tralomethrin, fenvalerate, etofenprox, silafluofen, Hoe-498, bifenthrin, for example, neonicotinoid insecticides such as nitenpyram, imidacloprid, acetamiprid and the like, and as a pest repellent Include, for example, dibutyl succinate, dibutyl phthalate and the like.

Among these additives, preferred are preservatives, and more preferred are organic iodine-based preservatives having extremely low fish toxicity.

These additives may be used alone or in combination of two or more in a proportion that does not give a fish poisoning effect. For example, in the case of an organic iodine-based preservative, it is added in the range of 100 to 2,000 ppm in an aqueous chitosan solution. Is preferred.

The chitosan or the aqueous solution of chitosan thus obtained is commercially available, and such a chitosan can be used as appropriate.

Then, pulverized coal and / or montmorillonite group minerals are blended with the above-mentioned aqueous solution of chitosan to obtain the plant pesticide for fish habitat of the present invention.

Examples of such pulverized coal include fine powder such as sawdust, charcoal, and activated carbon. Examples of montmorillonite group minerals include montmorillonite,
Magnesian montmorillonite, Tetmontmorillonite, Tetsumagnesian montmorillonite, beidellite, aluminian beidellite, nontronite, aluminonnontronite, sapstone, aluminian sapstone, hectorite, sauconite and the like.

The mixing ratio of the chitosan aqueous solution and the pulverized coal and / or the montmorillonite group mineral is 10 to 500 parts by weight, preferably 50 to 50 parts by weight, based on 100 parts by weight of the chitosan aqueous solution.
200 parts by weight.

In addition, at the time of compounding, it is only necessary to add directly, but it may be appropriately stirred.

The obtained plant pest control agent of the present invention may be applied as it is,
It may be applied after diluting it, preferably 50 to 400 times.

Further, they may be appropriately formulated and used. The form of the formulation is not particularly limited. For example, solutions such as solutions, wettable powders, suspensions, dispersants, emulsions, oils, and lotions, for example, solids such as powders and granules, for example, pastes , Creams and other semi-solids, other, sprays,
It can be used as an aerosol or the like, and these can be appropriately selected depending on the purpose of use and the place of application. For example,
It may be formulated into a predetermined shape such as a mat shape. Further, these preparations can be performed by a conventional method. Of these, a suspension, a powder, a spray and the like are preferable.

Since the pesticidal composition for fish-habiting areas of the present invention has extremely low fish toxicity, it can be effectively applied to areas where fish inhabit, such as rivers, ponds, swamps and seas. Pathogenic bacteria, for example, Fusarium, Visium, Phytophthora, Verticillium, Rhizoctonia, Pseudomonas, Erbinia, and the like, suppress the activity of plants, and diseases of plants derived from these bacteria, such as damping-off, Prevents the onset of acute wilt, vine rot, plague, bacterial wilt, yellow rot, root rot, seedling blight, etc., promotes rooting of plants, improves rooting and survival, and absorbs nutrients. Terrestrial pathogens, such as Alternaria,
Pestallotia, Colletotrichum, Botrytis,
Suppress the activity of Peronospora, Erysiphe, Puccinia, Xanthomonas, and other plant diseases derived from these bacteria, such as black spot, spot disease, anthrax, gray mold, downy mildew, and powdery mildew It can promote the growth of plants, such as preventing the onset of diseases, rust, spot bacterial disease, etc., and increasing the activity of plants to prevent the occurrence of pests.As a plant pest control agent or plant growth promoter , Can be used effectively.

In particular, with respect to waterlily plants such as lotus cultivated in ponds and the like, they effectively act on lotus wilt caused by Pycium fungi and have no effect on fish that live in the ponds. Without giving, healthy growth of lotus can be ensured.

[0033]

As described above, the plant pesticide of the present invention for fish habitats has extremely low fish toxicity, and thus can be effectively applied to areas where fish live, such as rivers, ponds, swamps, and the sea. Can suppress the growth of plant pests,
It can promote rooting of plants, improve rooting survival and increase nutrient absorption, and can enhance plant activity to prevent the occurrence of pests.

[0034]

The present invention will be described more specifically below with reference to examples and comparative examples.

Example 1 A chitosan aqueous solution was prepared in which chitosan (molecular weight: 40000 to 50,000, degree of deacetylation: 86.5%) and lactic acid each became 1.5% by weight.

Next, this chitosan aqueous solution was diluted 50-fold with a plant hydroponic solution, and 2% by weight of montmorillonite was added to the diluted solution to obtain a suspension-type plant pest control test solution.

Example 2 The same operation as in Example 1 was carried out except that 1% by weight of pulverized coal was added in place of 2% by weight of montmorillonite, to obtain a suspension test solution for plant pests. Was.

Comparative Example 1 Comparative Example 1 was prepared by diluting the aqueous chitosan solution 50 times in Example 1 and then adding no montmorillonite.

Comparative Example 2 A 2% by weight suspension of montmorillonite was prepared and used as Comparative Example 2.

Comparative Example 3 1% by weight of pulverized coal suspension water was prepared, and this was designated as Comparative Example 3.

Test Example (Fish Toxicity Test) In the liquids obtained in Examples 1 and 2 and Comparative Examples 1 to 3, medaka was allowed to swim, and the state of swimming after 24 hours was observed.

The evaluation is from +++ (active) to-(dead).
And (Disease suppression ability test) Cells (Phytophthora capsisii) cultured in advance in a CBA medium are immersed in MCZ solution to form zoospores, and then transferred to a germination promoting solution to swim zoospores. After being converted into cysts, the cucumber seedlings cultivated in each culture solution in the plant growing box were irrigated and inoculated at a rate of about 10 ³ cucumber seeds per ml, and cultivation was continued. The occurrence of dead blight was examined.

The results are shown in Table 1.

[0044]

[Table 1]

As is evident from Table 1, in Examples 1 and 2, the medaka was still actively swimming even after 24 hours, and there was no onset of the dead blight of cucumber seedlings.
On the other hand, in Comparative Example 1, the killifish was dead, and in Comparative Examples 2 and 3, 100% became ill.

[0046]

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-7-25680 (JP, A) JP-A-60-142902 (JP, A) JP-A-53-59027 (JP, A) JP-A-5-59027 39207 (JP, A) JP-A-53-127824 (JP, A) JP-A-9-143013 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) A01N 63/00 A01N 59 / 00 CAPLUS (STN) REGISTRY (STN) WPIDS (STN)

Claims (1)

(57) [Claims] 1. A plant pest control agent for fish habitat comprising chitosan and pulverized coal and / or montmorillonite group minerals.