EP2184976A1

EP2184976A1 - Device and method for exposing an insect to an active agent, and method for determining the effect of an active agent on an insect

Info

Publication number: EP2184976A1
Application number: EP08803541A
Authority: EP
Inventors: Burkhard Bauer
Original assignee: Freie Universitaet Berlin
Current assignee: Freie Universitaet Berlin
Priority date: 2007-09-06
Filing date: 2008-09-02
Publication date: 2010-05-19
Also published as: WO2009030686A1; DE102007043006A1; DE102007043006B4

Abstract

The invention relates to a method for exposing an insect to an active agent, comprising the steps of providing a container (1) defining an interior (3) and having an active agent within the interior (3), wherein the interior is equipped with an active agent carrier (6) receiving the active agent and/or a surface of the interior (3) is coated using the active agent; inserting at least one insect into the interior (3) of the container (1); and closing the container (1) such that the insect may not exit the interior (3), and the interior (3) is darkened such that the insect substantially stops flying. The invention further relates to a corresponding device for carrying out the method, and to a set of multiple devices differing with regard to the active agent and/or the concentration thereof.

Description

Apparatus and method for exposing an insect to an active ingredient and method for determining the effect of an active ingredient on an insect

description

The present invention relates to a method for exposing an insect with an active ingredient according to the preamble of claim 1, a method for determining the effect of an active ingredient on an insect according to the preamble of claim 7, an apparatus for exposing an insect with an active ingredient according to the preamble of claim 11 and a set consisting of at least two devices for the exposure of an insect with an active substance according to the preamble of claim 18.

The determination of the effect of an active ingredient on an insect is particularly important with regard to the effect of insecticides or other active substances on noxious insects. Insect insects are understood to mean all insects of medical or veterinary significance as well as storage pests and comparable insects.

Various methods are known from the prior art to expose an insect to be examined with an active substance to be tested. Thus, insects are often exposed to the test insect by spreading the test compound at different concentrations directly. In another method known from the prior art, the insects to be tested are exposed in Petri dishes with the active substance to be tested, which was previously applied to filter plates which are in the Petri dishes be introduced. Characteristic of the methods known from the prior art is a relatively small number of insects to be examined simultaneously and a not inconsiderable expense of the individual methods. Furthermore, it is necessary to fix the test insects before their exposure to the drug to be tested. This sometimes causes problems that can lead to a misjudgment of the investigation performed. In addition, the required fixation of the test insects results in a stress situation for the test insects, which can lead to an increased susceptibility to the active substance to be tested or an increased mortality.

This is especially true because in the above-described prior art method employing petri plates with filter plates inserted therein for assaying the efficacy of an active substance on a test insect, at least one cooling step is performed which contributes to further stress loading of the test insects. Often a two-time cooling and with 30 min. A relatively long time of exposure at high drug concentration is applied. These unphysiological examination conditions favor an increased mortality, which is not directly due to the drug to be tested, but rather due to the examination conditions.

From US 2005/0284018 A1 there is known a walk-in test chamber having a projector for projecting a grid onto the floor of the test chamber, an automatic washer-cleaner, the ability to simulate authentic insecticide application conditions and / or an automatic aerosol delivery device. In this test chamber insects are introduced under laboratory conditions, to then put them with an insecticide in the form of an aerosol. Subsequently, the effectiveness of the insecticide is determined by the number of insects killed.

The present invention is based on the problem of providing a method and a device for the exposure of an insect with an active ingredient, wherein the exposure takes place under physiological conditions.

This object is achieved by a method for exposing an insect to an active ingredient having the features of claim 1. Such a method has at least three steps, namely first providing a container (or container) which has an interior, which itself has an active substance, wherein the interior is provided with a drug carrier which receives the active ingredient, and / or a Surface of the interior is coated with the active substance, then introducing at least one insect into the interior of the container and finally closing the container, so that the insect can not leave the interior and the interior is at the same time darkened such that the light intensity acting on the insect in the interior is so low that the insect Insect essentially ceases its flight activities. On the contrary, due to this darkening, the insect settles on the surface of the interior, which is prepared in particular with an active substance to be tested. In this case, the insect absorbs the test substance in a physiological manner via its end limbs.

As a result of this physiological exposure or contacting of the insect with the active substance to be investigated, there is less damage to the insect than in the methods according to the prior art. This is particularly important in fragile insects such as mosquitoes of particular importance. In addition, it is possible to test large amounts of insects simultaneously and in a short time with the method according to the invention. It is not necessary that only a single insect is introduced into the interior of the container. Also, the use of the method according to the invention is not tied to a complex infrastructure. It can be used everywhere - even in the field.

The often uncontrolled use of insecticides or other substances acting on insects increasingly leads to the emergence of resistances in insect pests. The method according to the invention permits a user-friendly examination of pest insects in the event of a suspected resistance, a so-called "screening." The area-wide inspection of agricultural holdings can be carried out inexpensively by means of the method according to the invention without great expense.

In one embodiment of the invention, the active ingredient is an active substance which influences at least one of the following parameters: vitality, lifespan, survivability, reproducibility and development of the insect and / or its offspring.

In one embodiment of the invention, the active ingredient is selected from a group comprising hormones, insecticides, sterilizing agents and toxins. In particular, the following insecticides are suitable: 1. Sulfur-containing products: Mesulfen, Cymiazol; 2. Chlorin-containing products: clofentotane, lindane, bromociclene, tosychloramide; 3. Pyrethrins and Pyrethroids: Pyrethrum, Bioallethrin, Phenotrin, Permethrin, Flumethrin, Cyhalothrin, Flucythrinates, cypermethrin, fluvalinates, deltamethrin, cyfluthrin, tetramethrin, fenvalerate, acrinathrin; 4. amidines: amitraz and combinations; 5. Carbamates: Carbaril, Propoxur, Bendiocarb; 6. Organophosphates: Phoxim, Metrifonate, Dimpylate, Dichlorvos, Heptenofos, Phosmet, Fention, Coumafos, Propetamphos, Cythiate, Bromphos, Malathion, Quintiophos, Tetrachlorvinphos, Bromvinphos, Azamethiphos; 7. Organic acids: formic acid, lactic acid, oxalic acid.

Furthermore, the following agents are suitable for use in the process according to the invention: other ectoparasiticides such as pyriproxifen, fipronil, pyripoles, imidacloprid or spinosad. Further, triflumuron and other related surfactants having sterilizing properties are suitable.

For example, juvenile hormones can also be used as sterilizing agents. These juvenile hormones intervene in the chitin metabolism of insects, so that it subsequently comes to problems with egg or larval deposit. In particular, hormones can be used that prevent the natural molting process of the larvae. Suitable inhibitors of chitin synthesis are, in particular, lufenuron, diflubenzuron and / or telinbenzuron. In addition, insect growth regulators such as methoprene are also suitable as agents.

As toxins, for example, the following substances can be used in one embodiment of the method according to the invention: bacterial poisons such as that of Bacillus thuringiensis and comparable toxins.

In order to minimize the stress on the insect or insects to be examined, the method can be carried out in an embodiment of the invention at ambient temperature. This ambient temperature can for example at about 18 to about 30 ⁰ C, in particular at room temperature (ie, about 20 to 25 ⁰ C), take place.

In one embodiment of the invention, to limit residence time of the insect in the container, after the step of closing the container, the method includes a further step of opening the container so that the insect can exit the container. The residence time of the insect in the container is thus determined by the period during which the container is closed.

In a preferred embodiment of the invention, the residence time of the insect in the interior of the container is (only during this period of stay there is the possibility that the insect absorbs the active ingredient in a physiological manner), between 1 second and 10 minutes, in particular between 1 second and 3 minutes, and especially between 5 seconds and 1 minute. Particularly preferred residence times or exposure times are 10 seconds, 20 seconds and 30 seconds.

In order not only to enable the insect to be exposed to the active ingredient, but also to be able to make statements about the effect of the active ingredient on the insect, in a preferred embodiment of the invention the method according to the invention is supplemented by further steps which comprise the method for the exposure of an insect with an active ingredient to a method for determining the effect of an active ingredient on an insect. These steps include transferring the insect from the drug-bearing container into an observation cage (or other suitable observation container) and then observing the insect in the observation cage during a defined observation period. If during the observation period behaviors of the insect are associated with the effect of the tested active ingredient, the effectiveness of the active ingredient on the insect is given. In this way, for example, resistances of the insect to the tested active substance can be detected very quickly.

The observation period is preferably 1 minute to 48 hours, with observation periods of 12 to 24 hours or of 1 minute to 60 minutes being preferred, depending on the active substance to be tested. In particular, observation periods of about 24 hours or from 5 minutes to 30 minutes and more particularly from about 10 minutes to about 20 minutes are suitable. As a rule, an observation time of 15 minutes is sufficient to observe effects of the active ingredient on the insect, especially when examining an insecticide. It can generally be assumed that the insect, if it does not exhibit any behavioral abnormalities attributable to the active substance within 15 minutes after the end of the exposure or the contact with the active substance, possesses no susceptibility to the active substance.

In such a case of non-receptivity, the previously described method for determining the effect of an active ingredient on an insect may be supplemented by a further step comprising re-performing the previous steps, whereby the concentration of the active ingredient is increased compared to the previous one. In other words, it is initially assumed that, although the active principle can have an effect on the insect, the concentration used in the interior of the insect However, the container was considered too low. After an increase in concentration - if necessary, several concentration levels such as 3 different concentrations can be used - and re-observation of the insect in the observation cage after exposure of the insect with the drug even more reliable statements can be made about the effect of the drug on the insect, as if only one concentration would work. Suitable drug concentrations are in a range of about 1 mg of active ingredient per square meter of the interior of the container to about 1000 mg / m ² , with a lower concentration limit of 50 mg / m ^{2 is} also advantageous. In particular, it is advantageous to work at an active ingredient concentration of about 100 mg / m ² .

The method according to the invention is preferably carried out using a device having the features of claim 11. Such an apparatus for exposing an insect to an active substance has a container which defines an interior which itself contains an active substance. According to the invention, the container is provided and arranged to be closed in such a manner that the interior is darkened so that an insect introduced into the interior substantially completely stops its flight activities.

In this case, the interior of the container is provided in a first variant with a drug carrier having the active ingredient. This means that the container is not provided directly with the active ingredient, but rather an additional drug carrier layer is arranged in the container. The drug carrier may be a substance which is prepared with the substance to be tested, for example, impregnated, is. Thus, for example, a cotton fabric which is impregnated with a speaking active substance can be used as the active substance carrier.

In this way, effects of a drug applied to a clothing can be examined directly under application conditions. In particular, it can thus be investigated whether an active substance is released by a certain fabric fiber in the desired manner. In this way, it is possible to avoid incorrectly interpreted experimental results based on the fact that only one active substance per se, but not one active ingredient in its actual field of application, is investigated.

The interior of the container may be lined with the drug carrier in particular. Instead of a substance, the drug carrier can also be made of any other material be prepared. For example, plastic films, nonwovens and paper-based materials are suitable as active substance carriers.

The drug carrier can be provided with a, in particular adhesive, means to allow easy adhesion to the inner surface of the container. This adhesion can be reversible, so that the container after removal of a first drug carrier can be provided with a second drug carrier and can be used again.

In a second variant, at least one surface of the interior is directly coated with the active ingredient. This embodiment of the invention is particularly useful when the effect of an active ingredient is to be examined per se, but not in a specific context with a drug carrier. The coating of the surface of the interior can take place, for example, by applying or spraying the active substance onto the surface of the interior. Also, an impregnation of the material from which the container is conceivable with the drug to be tested. In this case, the impregnation can take place, for example, such that only the inner space, but not an outer surface of the container, is impregnated with the active substance.

The first and second variants can also be used together.

In a preferred embodiment of the invention, the container is made of a material which comprises paper, cardboard and / or a plastic or consists entirely of these materials. Combinations of these materials are conceivable. Due to a large number of suitable materials, a device according to the invention can be adapted to the most diverse requirements with regard to transportability, foldability, mobility, production costs and production method.

The concentration of the active ingredient on the surface of the interior or on the active ingredient carrier is preferably between about 1 mg of active ingredient per square meter

Surface of the interior or of the active ingredient carrier and about 1000 mg active ingredient / m ²

Surface. In particular, a concentration of about 10 mg / m ² to about 500 mg / m ² and very particularly a concentration of about 50 mg / m ² to 200 mg / m ² can be used. A

Concentration of about 100 mg active ingredient / m ² surface is an advantageous value to be used. In order to enable a simple introduction of the insect to be examined into the container, the container preferably has an inlet opening.

Although it is possible in principle to bring the insect out of the container through the inlet opening, in a preferred embodiment of the invention the container has an outlet opening provided for this purpose (rapid release of the insect or test insects from the container) and is set up.

In a preferred embodiment of the invention, both an inlet opening and an outlet opening are provided. It is particularly preferred if the inlet opening is smaller than the outlet opening. The outlet opening should preferably be as large as possible. In this way, insects can be very easily introduced into the container and again brought out of the container very quickly. It should be noted that the insects have to fly out of the container by itself or crawl out through the outlet opening. For this reason, a larger opening for spreading the insect out of the container is advantageous. The outlet opening is particularly designed and arranged to release the substance (s) exposed to the active substance as quickly as possible from the container into an observation cage connected to the container.

In order to allow a simple closure of the inlet opening or the outlet opening, the container preferably has a closure device which is provided for closing the inlet opening and / or the outlet opening. In this case, a single closure device for both openings may be provided, or it may also be two separate closure devices, each of which can close one of the two openings of the container, are used.

In order to enable a repeated use of the container, which is particularly advantageous if the surface of the interior is not directly coated with an active substance, but rather an active substance carrier is introduced or inserted into the interior of the container, the closure device is preferably designed such that in that it can close the inlet opening and / or outlet opening in a resealable manner. For this purpose, the usual known closure mechanisms are known to those skilled in the art, which allow a resealable closure (for example, Velcro, adhesive closure or plug closure). With regard to further preferred embodiments of the device is expressly also refer to the relevant above explanations regarding the inventive method.

In order to allow a particularly simple handling of the device according to the invention or a particularly simple implementation of the method according to the invention, the present invention also relates to a set of at least two devices for the exposure of an insect with an active substance having the features described above. In this case, the devices contained in this sentence differ at least partially with regard to the concentration of the active substance in the respective interior spaces of the containers or with regard to the type of active substance or the specific compound or composition to be used as active ingredient (with the same or different active substance concentration).

It is particularly preferred if the set or the set contains about 2 to 20, in particular about 2 to 10 and very particularly 3 to 5 devices of the aforementioned type. Thus, as a set a test kit of 3 devices of the aforementioned type can put together, which have a different concentration of the same active ingredient. Thus, the effect of this active ingredient on insects to be examined in a particularly simple manner perform. Initially, the lowest drug concentration is started. If an effect on the insect can be detected even at the lowest concentration of the active ingredient, the devices which have the active ingredient in a higher concentration in their interior no longer have to be used. However, if no effect of the active ingredient on the insect is detected, the method of determining the effect of an active ingredient on an insect using the device of the kit having the next higher concentration of the active ingredient in its interior is used. If no effect of the active ingredient on the insect is detected even at this concentration, the next device with the next higher concentration of the active ingredient is finally used. Otherwise, the study of the effect of the active ingredient on the insect can be stopped after the use of the second device from the set of devices.

As a set of devices that are at least partially related to the concentration of

Substance and / or the active ingredient itself, is also a compilation understood, the container produced in the same way (or even a single, reusable container), but at least partially different drug carriers having. This makes it easy to combine a wide variety of drug carriers with non-modified containers.

Advantageously, various sets of devices can be provided which cover different concentration ranges or a comparable concentration range in different resolutions. In this way, it is possible to carry out a coarse screening and a subsequent fine screening of a specific concentration range in order thus to determine an advantageously effective concentration range of the active substance. In this way, for example when investigating substances treated with an active substance, it is possible to prevent the use of unnecessarily high amounts of the active substance, since in a simple and efficient manner a lower efficacy concentration of the active substance can be avoided

Active substance can be determined.

Further advantages and details of the present invention will be explained in more detail with reference to the following figures. Show it:

Fig. 1 shows an embodiment of a device for exposing an insect with an active ingredient in perspective and

Fig. 2 is a cross-section through the device of Fig. 1 along the line A-A.

1 shows a perspective view of a box 1 as a device for the exposure of an insect with an active ingredient. The box 1 has a plurality of boundary surfaces 2, of which only a few are provided with the corresponding reference numerals for the sake of clarity. The boundary surfaces 2 enclose an inner space 3 of the box 1, which has an active substance, with which an insect to be introduced into the box 1 is to be exposed.

In this embodiment, the box 1 is about 20 cm long, about 6 cm wide and about 4 cm high. An insect to be examined is first placed in an unillustrated tube and then over a formed in a front side 2a of the box 1

Inlet opening 4 spent in the interior 3 of the box 1. The box 1 is then closed so that it is completely darkened. The insect thereby stops its flight activities and settles on an inwardly facing surface of one of the boundary surfaces 2 in the interior 3. The inlet opening 4 has a

Diameter of about 2.5 cm. The inlet opening 4 is in addition by a Locking device closable, which is not shown separately in the illustration of FIG.

After a predetermined period of time, the residence time, which is for example 10 seconds, the insect is then via an outlet 5, which in a

Rear side 2b of the box 1 is arranged, wherein the back 2b of the front side 2a of

Box is exactly opposite, again released from the interior 3 of the box 1. In a variant, the outlet opening 5 occupies the entire rear side 2b of the box 1, so that the insect can be released from the box 1 particularly quickly and easily. In this case, the outlet opening 5 is initially closed with a closure device, however, is opened for the purpose of releasing the insect from the interior 3 of the box 1.

In this case, the insect to be examined is not released into the outer space surrounding the box 1, but spent by the outlet opening 5 in an observation cage. This observation cage is not shown in FIG. 1. In this

Observation cage can then be followed by observation of the insect, the estimated observation period is already set and usually before

24 hours or less. To assess the susceptibility of an insect to a particular drug can also be a significantly shorter

Observation period of only about 15 minutes will be sufficient.

The arrangement of the inlet opening 4 and the outlet opening 5 need not necessarily take place on the front side 2a or the back side 2b of the box 1. Rather, any arrangement is possible on any of the boundary surfaces 2 of the box 1.

The box of Fig. 1 is made of cardboard. As a result, it is particularly lightweight and can also be designed in the form of a carton, so that it can be easily folded and consumes little space in a transport condition. If desired, the carton 1 can then be unfolded and used to carry out a method of exposing an insect to an active ingredient.

Fig. 2 shows a cross-sectional view through the box 1 of Fig. 1 along the line AA. In this illustration, the boundary surfaces 2 and the interior 3 of the box 1 surrounded by the boundary surfaces 2 can be seen. Parallel to the boundary surfaces 2 extends on the inside, ie, facing the interior 3 of the box 1 out a carrier provided with an active ingredient 6 as a drug carrier. The Box 1 is thus knocked out to its interior 3 out with the carrier 6. The carrier 6 is impregnated with a drug to be tested. Other methods of applying the active ingredient to the carrier 6 are also conceivable. The carrier 6 consists in the present example of a cotton fabric. It is also possible in an alternative embodiment of the invention that the carrier 6 is omitted and the active ingredient is applied directly to the inside of the outer surfaces 2 of the box 1.

_{* * * * ** * * * *}

LIST OF REFERENCE NUMBERS

1 box

2 boundary surfaces

2a front side

2b back side

3 interior

4 inlet opening

5 outlet opening

6 carrier

Claims

claims

A method of exposing an insect to an active agent, comprising the steps of:

a) providing an interior (3) defining container (1), which in the interior (3) has an active ingredient, wherein the interior is provided with a drug carrier (6) which receives the active ingredient, and / or a surface of the interior ( 3) is coated with the active ingredient,

b) introducing at least one insect into the interior (3) of the container (1) and

c) closing the container (1) such that the insect can not leave the interior (3) and the interior (3) is darkened such that the insect essentially stops its flying activities.

2. The method according to claim 1, characterized in that the active ingredient influences at least one of the following parameters: vitality, lifespan, survivability, reproducibility and development of the insect and / or its offspring.

3. The method according to claim 1 or 2, characterized in that the active ingredient is selected from the group consisting of hormones, insecticides, sterilizing agents and toxins.

4. The method according to any one of the preceding claims, characterized in that the method at ambient temperature, in particular at room temperature, is performed.

5. The method according to any one of the preceding claims, characterized in that it comprises after step c) the following further step:

d) opening the container (1) so that the insect can leave the container (1).

6. The method according to claim 5, characterized in that a residence time of the insect in the interior (3) of the container (1) is between 1 second and 10 minutes, in particular between 5 seconds and 1 minute.

7. A method for determining the effect of an active ingredient on an insect, characterized by a method according to any one of claims 5 or 6 and the following additional steps:

e) transferring the insect into an observation cage and

f) observing the insect in the observation cage during an observation period.

8. The method according to claim 7, characterized in that the observation period is 1 minute to 48 hours, in particular 12 to 48 hours.

9. The method according to claim 7 or 8, characterized in that the observation period is 5 to 30 minutes, in particular 10 to 20 minutes.

10. The method according to claim 7 or 8, characterized in that the method comprises the following additional step:

g) to carry out the previous steps again, the concentration of the

Agent is increased compared to the previous procedure.

1 1. A device for exposing an insect with an active ingredient, comprising a container (1) defining an interior (3), which in the interior (3) has an active ingredient, characterized in that the container (1) is provided and set up for this purpose to be sealed in such a way that the interior is darkened such that an insect introduced into the interior essentially stops its flight activities and that the interior is provided with a drug carrier (6) which absorbs the active substance and / or that a surface of the Interior (3) is coated with the active ingredient.

12. The device according to claim 1 1, characterized in that the container (1) is made of a material which comprises paper, cardboard and / or a plastic.

13. Device according to one of claims 1 1 or 12, characterized in that the active ingredient has a concentration of 1 mg / m ² to 1000 mg / m ² , in particular a concentration of 10 mg / m ² to 500 mg / m ² and especially a concentration of 50 mg / m ² to 200 mg / m ² .

14. Device according to one of claims 1 1 to 13, characterized in that the container (1) has an inlet opening (4) which is provided and adapted to introduce at least one insect through them into the interior space (3).

15. Device according to one of claims 1 1 to 14, characterized in that the container (1) has an outlet opening (5) which is provided and adapted to deploy at least one insect through them from the interior (3).

16. Device according to one of claims 1 1 to 15, characterized in that the container (1) has a closure device by means of which the inlet opening (4) and / or the outlet opening (5) can be closed.

17. The device according to claim 16, characterized in that the closure device is designed such that it allows repeated opening and closing of the inlet opening and / or the outlet opening.

18. Set consisting of at least two devices according to one of claims 11 to 17, characterized in that the devices contained in the set differ at least partially in terms of the concentration of the active ingredient and / or the active ingredient itself.

19. Set according to claim 18, characterized in that it consists of 2 to 20, in particular 2 to 10, especially 3 to 5 devices.