JPH0614824B2 - Method of pest communication disruption by sex pheromone - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for controlling mating disruption by a sex pheromone, in which the sex pheromone of a pest is drifted in the air to disturb the mating behavior of the pest and control by mating inhibition. It is a thing.

[Conventional technology]

The method of controlling communication disruption by sex pheromones has been attracting attention as a nontoxic pesticide in recent years. In this control method, the sex pheromone released by the pest female is kept in the air with a high concentration of synthetic pheromone that males cannot distinguish, and it disturbs male mating behavior and inhibits mating. is there. The most important factor in this method is the concentration of synthetic pheromone in the atmosphere within the community of plants where the pests mate. The higher this is, the higher the control effect is. Usually, since the period of generation of pests is long, a dispenser is used to gradually release the synthetic pheromone into the atmosphere for a long time. The higher the release rate, the higher the concentration in the atmosphere, but if it is too high, it is uneconomical. Therefore, it is necessary to keep the pheromone concentration in the atmosphere as high as possible while keeping the release rate of the pheromone from the dispenser at an economical level.

[Problems to be solved by the invention]

However, even if the same amount of sex pheromone is released to the field, there is often considerable variation in the effect of controlling communication disruption. This is because the pheromone may be rapidly diffused from the field due to differences in the field and weather conditions, and the concentration necessary for communication disruption may be insufficient. In this case, if the release rate of the sex pheromone is increased, the concentration in the atmosphere is increased and the control effect is enhanced, but there is a disadvantage that the expensive sex pheromone is consumed more than necessary.

The present invention has been made to solve the above-mentioned inconveniences, and suppresses the release rate of the pheromone from the dispenser to an economical level, regardless of the change of the weather and the state of the field, and An object of the present invention is to provide a method for controlling communication disruption by a sex pheromone, which can maintain a high concentration of pheromone in the atmosphere for a long period of time and can achieve a higher communication disruption effect with a fixed amount of pheromone.

[Means for solving problems]

In order to achieve the above-mentioned object, the inventors of the present invention have earnestly studied how to keep the pheromone concentration in the atmosphere in a plant community high in an economically advantageous manner. First, we analyzed how the current atmospheric pheromone concentration is affected by field conditions. Therefore, we established a method for measuring the pheromone concentration in the air of pheromone-treated fields, and based on this, measured the pheromone concentration in the air of pheromone-treated fields with a constant release amount per unit area and time. The progress is described below. The release rate of pheromone (Z-11-tetradecenyl acetate) is 180 mg / ha · hr., And the measured height is 70 cm above the ground.

Pheromone concentration of 80ng in an apple garden with a wind speed of 0.1m / sec
The pheromone concentration in a tea garden with a wind speed of 1 m / sec is 25 ng / m ³ with respect to (nanogram) / m ³ .

Pheromone concentration 25 ng / m in a tea field with a tea ridge spacing of 30 cm
^{On the} other hand, the pheromone concentration in a tea field with a tea ridge spacing of 50 cm is 11 ng / m ³ .

The pheromone concentration is 25 ng / m ^{3 in} the central part of the tea garden where the pheromone treatment is applied to one side, whereas it is 13 ng / m ³ on the 8 m wide road.

Pheromone concentration on the slope is lower 16ng / m ³ , middle
13 ng / m ^3, a top 7 ng / m ^3.

According to the above measurement results, per unit area and time,
Despite being released a certain amount of pheromone and pheromone concentration in the atmosphere is 7 ng / m ³ to 80 ng / m ^3, and a difference occurs in more than about 10 times, the wind speed is stronger, the wind passage , Or the upper part of the slope, the pheromone diffuses to a lower concentration. This is because, for example, when the amount of emission from a pheromone dispenser is doubled (the cost is about 2
It is a much larger difference.

The method of controlling pest mating disruption by sex pheromone of the present invention made based on the above findings, in a substantially flat field,
In the vicinity of the ground surface on the outer periphery of the field, at the position where at least the gap between the aligned crop groups or / and ridges is closed, the air resistor having a height from the ground surface of about 30 cm or more is provided, and the sex pheromone is dispensed by a dispenser. Is characterized by dissipating.

Similarly, the method for controlling interfering pests by sex pheromones of the present invention, in a sloping field, is at least near the ground surface on the lowland side of the outer periphery of the field, and at least the aligned crop groups or / and ridges. The air resistor whose height from the ground surface on the lowland side is about 30 cm or more is provided at a position to close the gap, and the sex pheromone is diffused by the dispenser.

The air resistor has only to fulfill the role of reducing the flow of air containing pheromones.For example, a windbreak net such as a gauze cloth, a fence made of wood or plastic parallel plates, or a block or a sandbag. Can be mentioned.

The height of the air resistor should be 30 cm or more, but if it is less than 30 cm, its effect is small. Lower limit of air resistor height 30
cm is not significantly affected by crop height. The reason is,
The sex pheromone has a higher specific gravity than air, and the sex pheromone released from the dispenser stays at a high concentration near the ground surface,
This is because it gradually spreads to the height at which insect mating behavior takes place. Even if the crop is as small as 10 cm,
Since insects copulate at higher altitudes, the air resistance must be at least 30 cm high.

The higher the air resistance is, the more effective it is, but the range in which mating behavior of pests is possible, that is, about the same height as the crop, or about 20% higher than that is sufficient. However, for example, in the case of a large plant body having a length of 4 m or more, providing a large-scale air resistance body of 3 m or more may cause an operational inconvenience, but even when the height is less than the above. , You can get a sufficient effect.

The air resistor used in the present invention is provided at the end of the pheromone-treated field, but the pheromone concentration can be kept sufficiently high even if it is installed only at the leeward side of the field or at the lower end of the inclined surface. I can. Further, when the crop body in the field itself prevents the flow of wind and air, the air resistor may be provided only in the portion that becomes the flow path of wind and air at the end of the field.

For example, as shown in FIG. 1, in the case of a tea garden 10 or the like, the spacing between the tea ridges 12 is clear, and the space between the tea ridges 12 is an air flow path 1.
It becomes 4. Therefore, the air resistor 1 is provided only at the end of the flow path 14.
If 6 is installed, the tea ridge 12, that is, the tea tree itself, acts as an air resistor and the pheromone concentration can be kept high.

As shown in FIG. 2, the farm field 10 is an inclined surface, and the tea ridge 12
When a is along the inclined side, the air resistor 16 may simply be installed at the lower end 18 of the inclined surface. Air resistor 16a
Is preferably installed, but even if this is omitted, the brown ridge 12a substantially functions as an air resistor. Further, since the air resistor 16 extends close to the brown ridge 12b, the brown ridge 12b substantially functions as an air resistor with respect to the A side of the field 10. Therefore, it is not always necessary to provide an air resistor at the boundary between the A side and the B side. Since the ground surface substantially acts as an air resistor at the upper end 19 of the inclined surface, it is not necessary to provide an air resistor.

As shown in FIG. 3, when the farm field 10 is an inclined surface and the trees are scattered sparsely, it is only necessary to install the air resistor 16 in the U-shaped outer peripheral portion 38 on the lowland side. On the highland side, the ground surface substantially acts as an air resistor, and therefore it is not always necessary to provide the air resistor along the entire inclined side. This is because the sex pheromone has a high specific gravity and stays at a high concentration near the ground surface on the lowland side in a field with an inclined surface, and gradually spreads to the highland side so as to cross the ground surface.

[Action]

The air resistor of the present invention suppresses the diffusion rate of the pheromone by weakening the wind in the community in the pheromone-treated field, and prevents the released pheromone from escaping from the field. In this case, since the pheromone is heavier than air, the concentration near the surface of the ground is high even in the field, and the pheromone becomes diluted with increasing distance from the surface. Therefore, it is possible to effectively prevent the high concentration of pheromone from spreading out of the field even with an air resistor having a surface height of about 30 cm. Then, the pheromone concentration that disturbs and inhibits the pest mating behavior in the field is maintained.

〔Example〕

 Hereinafter, examples will be described in detail.

Example 1 As shown in FIG. 2, a tea plant 10 having a rectangular shape of 30 m × 60 m (interval 40 cm between tea ridges 12 and tea plant height 80 cm and slightly tilted to the south side) was added to the pheromone formulation Hamakicon (Shin-Etsu Chemical Co., Ltd.). (Z-11-tetradecenylacetate agent) (540 pieces) are evenly attached, and a pheromone-treated field in which the air resistor 16 is installed in a plane L shape on the lower end portion 18 and the side portion 20 of the inclined surface is used as follows. The pheromone concentration in the atmosphere was measured under various conditions. The pheromone release rate within the measurement time is 160 mg / ha.
・ It is hr.

Install poles at points A and B in Fig. 2, respectively, and
Attach an absorption tube filled with 100 mg of fibrous activated carbon to a height of 70 cm, connect it to an air pump with an intake speed of 12 / min, and
From the time to 4 o'clock the next morning, suction was simultaneously performed for 8 hours at points A and B, and pheromones in the atmosphere were collected. The activated carbon after collection was extracted with n-hexane and then quantified by gas chromatography to determine the pheromone (Z-1
1-tetradecenyl acetate) concentration is determined.

Further, Table 1 shows the results of measurement by changing the air resistor 16 of FIG. 2 variously.

Example 2 As shown in FIG. 3, about 30 ares of apple orchard 30 (tree height of about 30 ares on the slope of a mountain that is damaged by peach mosquitoes every year.
On June 1 before the occurrence of the peach squid in 50m4), 450 pheromone preparations Shinuikon (Shin-Etsu Chemical Co., Ltd .; Z-13-1 Icosen-10-one preparations) were added to apple tree 32. Treated uniformly. Next, the apple orchard 30 is divided into a first block 34 and a second block 36, and a cold cloth with a ground height of 2 m is installed as an air resistor 16 in a generally U-shaped plane on the low-side outer periphery 38 of the first block 34. did.

When the damage fruit rate of peach squid was investigated at the time of harvest on October 28, it was 0.2% in the first block 34 and 4.5% in the second block 36. From this, it can be seen that the control effect due to the communication disturbance by the Shinkon icon was remarkably enhanced by providing the kansai with a height of 2 m above the ground.

〔The invention's effect〕

As described in detail above, according to the method of the present invention, the dissipation of pheromones is suppressed in the field where the pheromone treatment is performed. In particular, even in a field where pheromones are easily diffused, such as a windy field or a field having an inclined surface, the pheromone concentration in the atmosphere can be kept high for a long period of time.

Therefore, even if the amount of expensive pheromone released is reduced, it is possible to effectively control pests. Further, it is possible to prevent the air resistor from being installed more than necessary, and to minimize the equipment. As a result, it is possible to avoid an increase in the production cost of agricultural products and the like.

[Brief description of drawings]

FIG. 1, FIG. 2 and FIG. 3 are diagrams for explaining the implementation state of the method to which the present invention is applied. 10 ... Tea garden, 12 ... Tea ridge 14 ... Flow path, 16 ... Air resistor 18 ... Sloping surface lower end 20 ... Side, 30 ... Apple garden 32 ... Apple tree, 34 ... … First block 36 …… Second block 38 …… Lower side outer periphery

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Noboru Ainami 28 No. 28 Nishi-Fukushima, Kubiki Village, Nakakubiki-gun, Niigata Prefecture Shin-Etsu Chemical Co., Ltd.

Claims (2)

[Claims] 1. The air resistance at a height of about 30 cm or more from the ground surface at a position close to the ground surface at the outer periphery of a substantially flat field and at least closing a gap between aligned crop groups and / or ridges. A method for controlling the communication disturbance of a pest by a sex pheromone, which comprises providing a body and releasing the sex pheromone with a dispenser. 2. The height from the ground surface on the lowland side is substantially at a position near at least the ground surface on the lowland side in the outer peripheral portion of the sloping field, and at a position that closes at least a gap between aligned crop groups or / and ridges. A method for controlling communication disturbance of a pest caused by a sex pheromone, which comprises providing the air resistor of 30 cm or more and discharging the sex pheromone with a dispenser.