JPH0925207A - Fumigation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable to control various harmful insects such as snout beetles in a fumigation time equivalent to methyl bromide fumigation by combinedly using specific two compounds. SOLUTION: Hydrogen phosphide or a metal phosphide generating hydrogen phosphide is combinedly used with carbonic acid gas. A concentration of the hydrogen phosphide is 0.3-2g/m<3> and a concentration of the carbonic acid gas is 5-10%. As the metal phosphide, aluminum phosphide, magnesium phosphide or zinc phosphide, etc., can be used. As a fumigation method of vegetoanimal products and their processed materials, e.g. as shown in the figure, tapioca pellets are stowed in the hold of a grain carrier and a required amount of aluminum phosphide is administrated onto the surface of the tapioca pellets in a state of opening a hatch of the hold, the hatch is closed and sealed. Next, a circulator sucking a gas from a pipe 2 and ejecting from a pipe 3 is driven and CO2 is administrated from a pipe 1 while ejecting air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fumigation method used for exterminating insect pests of animal and plant products and processed products thereof (for example, live plants, grains, woods or bone meal).

[0002]

2. Description of the Related Art Methyl bromide, which is widely used as a soil disinfectant and a disinfectant for plant quarantine at the 4th Conference of the Parties to the Montreal Protocol held in Copenhagen in 1992, is a regulated substance for ozone layer protection. Specified in. In addition, in the United States, in addition to this resolution, it was resolved in 2000 to ban the production and use of methyl bromide. In the field of plant quarantine and the like, which are highly dependent on methyl bromide due to such international movements, there is an urgent need to develop an alternative drug for methyl bromide and an insecticidal method using the alternative drug.

So far, aluminum phosphide and methyl bromide have been used as fumigants. However,
In the case of methyl bromide fumigation, fumigation is possible for 24 hours, whereas aluminum phosphide fumigation currently used requires fumigation time of 3 days or more, so long-term occupation of fumigation sites and distribution of fumigation target cargo Not only is it economically expensive due to inhibition, etc., but it is also not sufficient as a substitute for methyl bromide, because it also has difficulty in the insecticidal effect of weevil pupae.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to develop a fumigation method capable of controlling harmful insects at a relatively low cost and with a fumigation time equivalent to that of methyl bromide fumigation.

[0005]

As a result of intensive studies to solve the above problems, the present inventors have used hydrogen phosphide or a metal phosphide generating hydrogen phosphide in combination with carbon dioxide gas. As a result, it was found that pests can be exterminated in a fumigation time equivalent to that of methyl bromide fumigation, and the present invention was completed based on this finding.

[0006] That is, the present invention relates to a fumigation method for animal and vegetable products and their processed products, characterized in that hydrogen phosphide or metal phosphide and carbon dioxide are used in combination. The term “animal and plant products” used in the present specification is a term used in customs statistics, and its meaning is obvious to those skilled in the art. It should be noted that the animal and plant products and their processed products that are the subject of the method of the present invention do not include those contained in airtight containers such as canned products.

As described above, when the fumigation treatment is carried out by using aluminum phosphide alone, it requires a fumigation time of 3 days or more at a constant concentration. On the other hand, if the pests are exterminated using only carbon dioxide, the carbon dioxide concentration is 50-60%.
Since it takes 2 weeks or more, it is not practical from the viewpoint of both cost and time. However, by fumigating these in combination, a killing effect is exerted on all eggs, larvae, pupae and adults of pests by fumigation for 24 hours, which is the same as fumigation with methyl bromide.
Such effects are unpredictable from the prior art.

The mechanism of killing pests by the method of the present invention is considered as follows. In other words, the respiration mode of insects is the same open organ system as plants, and oxygen is taken in through the openings called stigmas (usually 2 pairs in the chest and 8 pairs in the abdomen) that are connected to both sides of the body, Supplied directly to tissue. However, when the concentration of carbon dioxide exceeds a certain level, the parasite becomes acidic and carbon dioxide acts on the muscles that regulate the opening and closing of the stigmas, and the stigmas are opened and hydrogen phosphide gas or metal Hydrogen phosphide gas generated from phosphides is easily taken into the worm body with increased blood flow due to acidemia, resulting in death. Insect eggs do not have stigmas, but carbon dioxide gas and hydrogen phosphide gas permeate in the normal state, and death is caused by the same mechanism as described above.

In the fumigation method of the present invention, the kind of the target pest is not particularly limited, and it can be applied to all pests that breathe, and the pest can be any stage of eggs, larvae, pupae and adults. Good. In particular, according to the method of the present invention, a strong insecticidal effect is exhibited even on the pupa of weevil, which is difficult to be killed by conventional insecticides.

The fumigation method of the present invention can be carried out on animal and plant products and their processed products that are stored in places such as warehouses, silos, and holds that can be sealed. The target animal and vegetable products and processed products thereof are not particularly limited as long as they can be fumigated with methyl bromide, for example,
Agricultural products such as rice, wheat and corn, bone meal, wood and the like can be mentioned.

The fumigation according to the present invention is carried out by the following method. When using a metal phosphide, first, the metal phosphide is dosed into the storage or the hold, and then carbon dioxide is dosed using a pipe or the like, if necessary. When the carbon dioxide gas is dispensed, an outlet for air to be replaced so as to maintain normal pressure may be installed, or the inside of the storage or the hold may be depressurized in advance.

After that, the storage or the cargo hold is closed, and the generated mixed gas of hydrogen phosphide and carbon dioxide is promptly homogenized so that the gas concentration inside the fumigation target is 24.
Circulate around time.

On the other hand, when hydrogen phosphide and carbon dioxide are used as fumigants, a pipe or the like is used as necessary to administer the drug in the storage or the hold.

After that, fumigation is performed in the same manner as in the case of using the metal phosphide.

The concentrations of hydrogen phosphide and carbon dioxide used in the present invention may be appropriately determined depending on the conditions such as the object to be fumigated and the scale and structure of the storage. Generally, the concentration of hydrogen phosphide is 0.3-2 g / m ³ , preferably 1-2 g / m ³ .
m ³ and the carbon dioxide concentration is 5 to 10%. When a metal phosphide is used instead of hydrogen phosphide, an amount of the metal phosphide that is converted into the concentration of hydrogen phosphide and falls within the above range is used. As metal phosphide,
Aluminum phosphide, magnesium phosphide, zinc phosphide, etc. can be used.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

[0017]

EXAMPLE Tapioca pellets were loaded in the hold of a grain carrier as shown in FIG. 1, and a hatch (not shown) of the hold was opened, and the tapioca pellets were dosed with the required amount of aluminum phosphide tablets, and the hatch was opened. Was closed and sealed. The dosage in this case was 2 g / m 2 of hydrogen phosphide based on the hold volume.
^{It was 3} equivalents.

Next, a gas circulation device for sucking gas from the pipe (2) and ejecting it from the pipe (3) is operated, and while discharging air from the air discharge port in the hold, the capacity of the hold is equivalent to 8% through the pipe (1). An amount of carbon dioxide was dosed.

After the completion of the administration, the cargo hold is completely sealed, and a circulation device composed of the pipe (2) and the pipe (3) and a gas circulation device for sucking gas from the pipe (4) and ejecting the gas from the pipe (1) are both provided. It was operated for 24 hours.

After this fumigation treatment, the gauge containing the test insects consisting of four kinds of grain pests such as weevils at various stages of development placed in the tapioca pellets was taken out, and the test insects were examined over time. No surviving insects were found.

[0021]

EFFECT OF THE INVENTION By using hydrogen phosphide or a metal phosphide that generates hydrogen phosphide in combination with carbon dioxide gas, various grain pests such as weevils can be treated in a fumigation time almost equal to that of methyl bromide fumigation. Disinfectable

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment in which the fumigation method of the present invention is applied to tapioca pellets loaded in a hold.

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical indication location A01N 59:04) (72) Inventor Tsutomu Sugiyama 4-14-8 Chuo, Nakano-ku, Tokyo (72) Inventor Masaki Yanagihira 3-3 Shin-Matsudo 3-A1003, Matsudo City, Chiba Prefecture

Claims (3)

[Claims] 1. A fumigation method for animal and plant products and their processed products, which comprises using hydrogen phosphide or a metal phosphide in combination with carbon dioxide. 2. The metal phosphide is aluminum phosphide,
The fumigation method according to claim 1, which is selected from the group consisting of magnesium phosphide and zinc phosphide. 3. The fumigation method according to claim 1, wherein the animal and plant products and their processed products are agricultural products and wood.