JP3015607B2 - Communication disruption method using pheromone preparation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling insect pests by disrupting communication, in which a sex pheromone substance (hereinafter simply referred to as pheromone) of a pest is suspended in the air to inhibit the mating behavior of the pest.

[0002]

2. Description of the Related Art One of the methods for controlling pests is a so-called communication in which a large amount of synthetic pheromone is suspended in the air, and the pheromone released by the female pest is indistinguishable by males, thereby inhibiting the mating behavior of the pest. There is a disturbance method. At present, the concept of integrated pest control has become general,
Attention has been paid to the use of pesticides, and the future is expected. Since pests generally occur repeatedly from spring to autumn, control using pheromone is carried out by installing a pheromone preparation in a field during the first generation of adult worms and releasing the pheromone from summer to autumn. Due to such a long period of occurrence of the pest, a sustained-release pheromone preparation that gradually releases the pheromone is used for controlling the pest. Various modifications have been made to this sustained-release pheromone formulation since ancient times, and several types of formulations have been put to practical use.

[0003] As a first type, there is a type in which a pheromone is stored in a capillary tube having an open end, and the pheromone is released from the open end (US Patent No. 40170).
No. 30). The life is short because the amount of pheromone carried per preparation is extremely small. The second type includes
A laminate obtained by laminating another polymer layer as a control layer on a polymer-supporting layer mixed with a pheromone (US Pat.
No. 160335) or a porous carrier impregnated with a pheromone coated with a control film such as polyethylene to control the permeation of the pheromone to the outside (Japanese Patent Laid-Open No. 59-13701,
-59734 and U.S. Pat. No. 4,444,641). All of these preparations have in common that pheromone loss remaining without being released is large. The third type is a microencapsulated pheromone (U.S. Pat. Nos. 2,800,457, 2,800,458, 3,575,755, etc.), which is expensive due to the high cost of microencapsulation and the loss of pheromone. Is not small,
Due to the large surface area, the release rate is too high and the service life is short, for example, it is not widely used.

A fourth type is a container in which a pheromone is filled in a container such as a thin tube or ampoule made of a polymer film having a uniform and single membrane. This type includes those using a film material having a specific equilibrium swelling ratio with respect to the pheromone (JP-A-62-195303, etc.). This container is generally made of a thick film made of polyolefin and has a sustained release and long life, but the release amount of pheromone that swells and penetrates the vessel wall and diffuses outside depends on the temperature. As a result, the following problem was brought. In other words, when pheromone preparations are used throughout the year, the first generation of pests occurs mostly in the early spring, when the temperature is low.Therefore, in order to secure the release amount at this time, for example, the film thickness is reduced or the polyolefin is not used. The use of a substance having a low barrier property against pheromone, for example, by lowering the crystallinity, not only causes excessive release at high temperatures in summer, but also increases the amount of pheromone leached and retained on the outer wall of the preparation. For this reason, when the release amount is adjusted in accordance with the high temperature period, the release amount at the low temperature, particularly at the initial stage, is too small, resulting in a shortage of capacity. In addition, the leaching of the pheromone to the outer wall of the preparation described above is because the pheromone of these Lepidoptera pests generally comprises an unsaturated aliphatic aldehyde having 10 to 22 carbon atoms, acetate, ketone, carbohydrate and alcohol,
Degradation due to reactions such as multimerization, oxidation and cleavage, etc., and if the barrier properties were increased to avoid this, the amount of release at low temperatures in the early spring could not be secured sufficiently as described above.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a pheromone capable of preventing pheromone abundance and oxidation / cleavage deterioration in summer and preventing a pheromone from deteriorating and securing a sufficient amount of pheromone to be released even at a low temperature in early spring. It is intended to provide a method for disrupting communication using a preparation.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to achieve the above object. As a result, first, in a pheromone preparation in which a pheromone is filled in a hollow polyolefin container, 1) the pheromone preparation is carried out. The amount of pheromone absorbed can be arbitrarily adjusted depending on the temperature and the period during which the pheromone preparation is left; 2) When the pheromone is absorbed in the vessel wall in advance, compared to when the pheromone is not absorbed at all, 3) If the pheromone is absorbed into the vessel wall, the diffusion itself of the pheromone molecules in the film becomes large; 4) the absorption of the pheromone into the vessel wall, especially the actual use temperature (common) If the water is absorbed at a higher temperature than the normal climatic conditions, the amount of release will be large at the beginning of the release due to the pheromone in the vessel wall that is excessively absorbed,
In addition, the pheromone solubility in the vessel wall and the diffusion of the pheromone molecule in the film also increase, so that the release behavior particularly at low temperatures is significantly different; The chains are thought to relax, and the degree of relaxation depends on the temperature. Pheromone molecules enter the gaps between the relaxed polymer chains and determine the swelling rate, but once the polymer chains relax, they return to a steady state. Speed is
6) Extremely slow compared to the rate of change from the tension state to the relaxation state; 6) Even at the same swelling rate, the higher the temperature, the greater the fluctuation of the pheromone molecule and the polymer chain molecule.
The polymer chain is in a more relaxed state; Therefore, the present inventors further performed an absorption treatment, particularly at a temperature higher than the actual use temperature, before using the polyolefin pheromone preparation, and absorbed 2% by weight or more of the weight of the container into the container wall. And found that pheromone preparations act more effectively, and completed the present invention.

That is, the present invention provides an equilibrium at 20 ° C.
A liquid sex pheromone substance is sealed in a polyolefin film container consisting of a homogeneous film having a swelling ratio of 2 to 6% at a low temperature in the early spring, and left at a temperature of 35 ° C. or more for a certain period to reduce the weight of the container. The present invention relates to a communication disruption method characterized by absorbing 2% by weight or more of a sex pheromone substance into a vessel wall and using the same as a sustained-release pheromone preparation throughout the year.

[0008] The polyolefin container used in the present invention is a thin tube made of a uniform film, which is produced by ordinary blow molding, two-stage drawing, extrusion molding, thermoforming and the like.
In the case of ampoules, hollow spheres, etc., the film thickness has a large effect on the release rate, and is preferably 0.2 to 2 mm. If this is smaller than 0.2 mm, the permeation rate in the membrane at high temperature is too high, and the balance with the evaporation of the pheromone from the outer wall of the container is lost,
A pheromone liquid film is formed on the outer wall of the container, and the pheromone is leached. On the other hand, if it exceeds 2 mm, the transmission speed is too low, and the release amount becomes too small especially at low temperatures. Examples of the material for the polyolefin container include polyethylene, polypropylene, polypentene, and copolymers thereof. In consideration of the molecular weight and polarity of the pheromone, polyethylene or ethylene-vinyl acetate copolymer is used. Ethylene copolymers are preferred.

[0009] The absorption treatment of the pheromone into the container wall will be described. The polyolefin used in the preparation is generally insoluble in the pheromone, but can absorb several to several tens% of the pheromone. Conventionally, as the material of the pheromone preparation, a material having an equilibrium swelling ratio of 2 to 6% at 20 ° C. has been considered preferable.
It became clear that it was affected by the properties and temperature of the polyolefin. For example, the swelling amount increases as the polyolefin crystallinity decreases, and the degree of relaxation of the polymer chains in the formulation wall differs under different temperature conditions even at the same swelling ratio. Is considered to be in a more relaxed state due to Brownian motion. Therefore, even at the same swelling rate, when absorbed at a high temperature, the speed of becoming a polymer chain state at the use temperature is slower, and it is considered that excessive release in the initial release is continued for a long time,
As a result, when the pheromone preparation is used from the early spring in a low temperature, it is preferable to absorb the pheromone at a temperature higher than the actual use temperature. As described above, in order to cause the pheromone to be absorbed in the polyolefin container in the present invention, the absorption process may be performed at a constant temperature for a certain period of time in consideration of the properties of the polyolefin, whereby the absorption amount in the container is arbitrarily adjusted. be able to.

As a specific example, a sustained-release preparation of an alcohol pheromone using a container made of an ethylene-vinyl acetate copolymer will be described. For release of an alcohol pheromone, a vinyl acetate content of 1 to 5% by weight is used. Are preferred. If it exceeds 5% by weight, the swelling ratio increases, and the affinity between the pheromone and the copolymer is too good, so that the pheromone is leached out into the vessel wall at high temperatures and deteriorates. If the amount is less than 1% by weight, the amount of release is small, and there is a limit to the amount of pheromone that can be released after the pheromone is absorbed by the vessel wall. In addition, this vinyl acetate content also affects the release amount of the pheromone itself, and when this increases, the release amount also increases, and a certain release amount can be secured even at a low temperature.
At high temperatures, the pheromone leaches out of the vessel wall and tends to deteriorate. On the other hand, when the vinyl acetate content is reduced, deterioration due to leaching of the pheromone at high temperature can be prevented, but a large amount of pheromone needs to be absorbed by the vessel wall in order to secure the release amount at low temperature.

Therefore, the desired absorption amount of the pheromone, that is, the weight percentage (S%) of the absorbed pheromone with respect to the ethylene-vinyl acetate copolymer container also depends on the vinyl acetate content (C%) of the copolymer. XC is preferably in the range of 3 to 50 (% ² ). This is because when the vinyl acetate content is relatively high, the release rate is somewhat high, so it is not necessary to increase the release amount at low temperature,
The amount of pheromone to be absorbed in the vessel wall in advance may be relatively small.On the contrary, when the vinyl acetate content is low, unnecessary release at high temperature is prevented, and the pheromone is prevented from deteriorating due to leaching into the vessel wall. Although it can be completely prevented, it indicates that it is necessary to secure a sufficient amount of pheromone to be released at low temperatures, and thus it is necessary to increase the amount of pheromone absorbed in the vessel wall in advance.

As described above, among the parameters caused by the container, factors that greatly affect the release rate of the pheromone include the average wall thickness (mm) of the container and the vinyl acetate content (% by weight). Regarding the relationship, the product of wall thickness T (mm) and vinyl acetate content C (% by weight) T × C is 1 to 5
(Mm ·%). This is because, in order to absorb an appropriate amount of absorption into the vessel wall for effective pheromone control, the volume (weight) of the vessel wall increases because the vinyl acetate content increases and the swelling amount of the vessel wall increases. This indicates that the volume (weight) of the vessel wall needs to be increased because the swelling amount decreases as the vinyl acetate content decreases.

[0013]

The present invention will be described below with reference to examples and comparative examples. Example 1 Z-8-dodecenyl acetate, which is a pheromone of Nashihime cinnamon, was placed in a narrow tube made of high-density polyethylene having an inner diameter of 1.17 mm, a thickness of 0.55 mm, a length of 200 mm, and a weight of 570 mg.
After filling with mg, a pheromone preparation in which both ends of the capillary were closed was prepared. The filling length at the time of filling was 195 mm. This was packaged in an aluminum bag and subjected to absorption treatment at 40 ° C for 14 days. As a result, the packing length of the pheromone was reduced to 155 mm, but the weight of the preparation did not change at all. Therefore, 36mg from reduced filling length
Minutes of pheromone is absorbed by the tube wall, which is 6.3% by weight of the capillary. This formulation was
Table 1 shows the results of determining the amount of release by setting the preparation in an apple field in early March of the year and measuring the weight of the preparation. From this, it was found that the amount of release was sufficient even in March and April in early spring, and uniform release was performed over the whole year.

Comparative Example 1 A pheromone preparation exactly the same as that of Example 1 was prepared. The pheromone was not absorbed into the tube wall, but was similarly installed in an apple field in early March 1990, and the weight of the preparation was measured. The amount of release was determined by performing the test, and the results are shown in Table 1. From this, it was found that the amount of release was significantly affected by the temperature, and the amount of release at low temperature in early spring was insufficient.

[0015]

[Table 1]

Example 2 In a capillary of an ethylene-vinyl acetate copolymer having an inner diameter of 1.22 mm, a wall thickness of 0.55 mm, a length of 200 mm, and a weight of 580 mg and having a vinyl acetate content of 4%, E-8, which is a pheromone of codlinger, was placed. E-
After filling 175 mg of 10-dodecadienol, a pheromone preparation in which both ends of a capillary were closed was prepared. Filling length at filling
It was 195 mm. This was packaged in an aluminum bag and absorbed at 40 ° C for 3 days.
But there was no change in the weight of the formulation. Therefore, 40.4 mg of the pheromone from the reduced filling length was absorbed into the tube wall, which is an absorption amount of 7% by weight based on the capillary. This formulation was placed on a pear field in Australia on October 1, 1990, and the amount of release was determined by weighing the formulation. The results are shown in Table 2. This is early spring
The amount of release was sufficient even at low temperatures in October, there was no excessive release in January to February in the summer, there was no stickiness due to leaching of the pheromone to the outer wall of the formulation, and the release was uniform throughout the year. all right.

Comparative Example 2 A pheromone preparation exactly the same as that of Example 2 was prepared, and the pheromone was not absorbed into the tube wall.
It was installed on a pear field in Australia on January 1 and the amount of release was determined by measuring the weight. The results are shown in Table 2. It was found that the amount of release was significantly dependent on the temperature, and that the amount of release at low temperatures in early spring was insufficient.

Comparative Example 3 The same pheromone preparation as used in Example 2 was prepared except that the vinyl acetate content was 12%, and the pheromone was not absorbed into the tube wall. Year 10
It was installed on a pear field in Australia on January 1 and weighed to determine the amount of release. The results are shown in Table 2. This formulation has a sufficient amount of cold spring release,
The release amount has become excessive with the rise in temperature since the month, and pheromones are released in vain. In addition, the pheromone leached out onto the outer wall of the preparation and became sticky, and the attachment of dust and dust was intense. As a result, the release rate was reduced in January to February.

[0019]

[Table 2]

Example 3 An ampoule made of an ethylene-vinyl acetate copolymer having an internal volume of 5 ml, an average wall thickness of 0.8 mm, and a weight of 1.7 g and having a vinyl acetate content of 3% was added to a sex pheromone E of Variation Leaf Roller (VLR). 1000 pheromone preparations filled with 300 mg of -11-tetradecenol were prepared. Each was packaged in an aluminum bag and subjected to absorption treatment at 40 ° C. for one week. There was no change in the weight of the formulation before and after treatment. Take out three of these,
Remove the filled pheromone and fill the ampoule wall with 5ml
After washing three times with ether, the ampule was weighed and found to be on average 50 mg more than the weight of the empty ampule before filling. Therefore, for the ampoule
This means that 2.9% by weight of the pheromone was absorbed by the vessel wall. This formulation was applied to US apple orchards on April 12, 1990.
Approximately 3 ha were installed at the rate of individual / ha to control the VLR. As a result, the attraction inhibition rate by the sex pheromone attraction trap was 95% or more from April to 3 months, and the damage result rate was 0.3% in the pheromone-treated group compared to 2% in the untreated group with the pheromone preparation.
%, A very high control effect was recognized.

[0021]

As described above, according to the communication disruption method of the present invention, it is possible to prevent the pheromone from deteriorating at high temperatures in summer, especially the leaching of the pheromone due to the leaching of the outer surface of the preparation, and to release the pheromone at low temperatures in early spring. On the other hand, a sufficient release amount can be secured by absorbing a certain amount or more of the pheromone into the formulation wall. Therefore, according to the present invention, an excellent control effect on communication disturbance can be obtained throughout the year.

──────────────────────────────────────────────────続 き The continuation of the front page (72) Akira Yamamoto, 28-1, Nishifukushima, Oaza, Kushiro-mura, Nakakushiro-gun, Niigata Prefecture Synthetic Technology Laboratory, Shin-Etsu Chemical Co., Ltd. (56) References JP-A-57-45101 (JP) , A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A01N 63/00 A01N 25/00 102 A01N 25/18

Claims (1)

(57) [Claims] An equilibrium swelling ratio at 20 ° C. of 2 to 6%.
A liquid sex pheromone substance is enclosed in a polyolefin film container made of a homogeneous film at a low temperature in early spring, and is left at a temperature of 35 ° C. or more for a certain period of time, and a sex pheromone substance of 2% by weight or more of the weight of the container. A method of disturbing communication, comprising absorbing the drug into a vessel wall and using the drug as a sustained-release pheromone preparation throughout the year.