EP1811843A2

EP1811843A2 - Method for control of termite populations

Info

Publication number: EP1811843A2
Application number: EP05821202A
Authority: EP
Inventors: Kim Watson; James B. Ballard
Original assignee: FMC Corp
Current assignee: FMC Corp
Priority date: 2004-11-16
Filing date: 2005-11-14
Publication date: 2007-08-01
Also published as: JP2008520571A; AU2005306648A1; WO2006055473A3; EP1811843A4; WO2006055473A2

Abstract

Acetamiprid is useful in a method for controlling a termite population comprising applying a termiticidally effective amount of acetamiprid to a termite from the population at a locus remote from the termite population.

Description

METHOD FOR CONTROL OF TERMITE POPULATIONS

This application claims the benefit of U.S. Provisional Application No. 60/628,457, filed November 16, 2004.

FIELD OF THE INVENTION

The present invention relates to the field of insecticides. Specifically, controlling unwanted termite populations.

BACKGROUND OF THE INVENTION

Termites are undisputedly the most destructive of all structural insects. In the USA termites are estimated to cause 1.5 billion dollars of damage to structures annually, and an additional one billion dollars is spent on treatment. These industrious insects work 24 hours a day, gradually eating wood and any other cellulose containing material in or close to their environment. Since they remain hidden within the wood in which they are feeding, in mud tubes, or in the soil, they typically wreak havoc undetected. Depending on the type of termite, a population can cover as much as 22,000 square feet. There are two types of termites, described as i) dry wood termites, and ii) subterranean termites. Of these two types, the subterranean termites usually live in the soil (i.e., soil-borne), from which they build mud tubes to structural wood where they then feed.

Besides sheer numbers and nearly undetectable movement, termite populations are also hard to control due to instinctual behavior. Fast acting termiticides kill termites soon after the termite comes in contact with them. When a large number of termites die shortly after feeding at a food source (i.e. treated structure or bait station), other termites in the population associate the death of their companion with the new food source and stop using that food source. Termites also behave this way around treated areas. This behavior is good for protecting a structure or area from termites moving into the structure or area. But this behavior is a problem if the goal is to kill the entire termite population within a structure or in an area. To minimize this problem slow acting, non-repellant termiticides, such as fipronil, imidacloprid or chlorfenapyr, have been used in conjunction with common methods to attempt control of termite populations. Unfortunately, the slow acting nature of these termiticides creates a new problem in prolonging the treatment period required to control the termite population. Therefore, the problem of controlling entire termite populations remains unsolved. As disclosed in European Patent Application 0 651 945, acetamiprid is a fast acting, non-repellant termiticide currently used by applying it directly to termite- outbreaking sites and nests of termites.

SUMMARY OF THE INVENTION In accordance with the present invention, it has now been found that a new method of using acetamiprid is useful in controlling termite populations. Based upon the known properties and normal use of acetamiprid, one skilled in the art would expect the fast acting nature of acetamiprid to impede the ability of treated termites to transfer the active ingredient to sufficient numbers of untreated termites to have a significant impact on the health and/or vigor of the termite population yet alone control of the population. It has been unexpectedly found that the present invention's method of use of acetamiprid for termite population control possesses an optimal balance of efficacy and transferal that allows for effective control of termite populations. Specifically, the invention is a method for controlling a termite population comprising applying a teraiiticidally effective amount of acetamiprid to a termite from the population at a locus remote from the termite population. Other aspects of the present invention will become apparent from the description below.

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling a termite population comprising applying a termiticidally effective amount of acetamiprid to a termite from the population at a locus remote from the termite population. The locus can be selected from a termite-infested structure, a structure that is expected to be termite- infested, a bait station, a monitor station, a crop, a tree crop or a location adjacent to said structure, crop, tree crop or station. Preferably, the acetamiprid is applied as a formulation wherein the acetamiprid is present in a concentration of from 0.001% by weight to 1% by weight based upon the total weight of all components in the formulation. More preferably, the acetamiprid is present in a concentration of from 0.01% by weight to 0.25% by weight based upon the total weight of all components in the formulation.

In the context of the present invention, the term "termiticide" refers to the active chemical compound or ingredient, such as acetamiprid, that kills termites or to a formulation of an active chemical compound or ingredient where the formulation can be dispensed in a suitable medium prior to its application to a locus where termite control is desired. The term "locus" or "loci" refers to any locations where control of termites is needed or is expected to be needed. Such locations include, without limitation, structures such as buildings and bridges, trees, posts, ^• poles, fences, bait stations, monitor stations, crops such as sugarcane, tree crops such as mangoes, rubber trees, oil palm, nut trees, tropical fruit trees and wood plantations and locations adjacent to structures, trees, posts, poles, fences, bait stations, monitor stations, crops, tree crops as well as other locations. The term "non-repellant" refers to a termiticide that does not drive back, ward off or keep termites away. The terms "mortality", "percent mortality", "control", "controlling", "percent control" or "managing" may be used interchangeably, and refer to the killing of and/or repelling of termites. The term "population" refers to a colony or colonies, infestation, gallery or group. The term "transfer" or "transferal" refers to a termite coming into physical contact with the acetamiprid and carrying it to its termite population where the acetamiprid is transferred to other termites through physical contact during movement in tunnels, grooming and oral or anal feeding.

A formulation that is particularly useful in the context of the present invention includes, without limitation, acetamiprid (sold under the name and trademark of INTRUDER and ASSAIL), sold as a 70% wettable powder (70WP). Wettable powders are in the form of finely divided particles, which disperse readily in water or other dispersant. The wettable powder is ultimately applied either as a dry dust or as a suspension in water or other liquid. Typical carriers for wettable powders include Fuller's earth, kaolin clays, silicas, and other highly absorbent, readily wet inorganic diluents. Wettable powders normally are prepared to contain about 5 - 80% of active ingredient, depending on the absorbency of the carrier, and usually also contain a small amount of a wetting, dispersing or suspending agent to facilitate dispersion. Using methods known to one skilled in the art, the above- mentioned formulation can be dispersed in an aqueous medium to provide a composition containing an insecticidally effective amount of an insecticide.

The following examples further illustrate the present invention, but, of course, should not be construed as in any way limiting its scope. The examples set forth certain biological data illustrating the effectiveness of the present invention in controlling termite populations. Unless otherwise indicated, all parts, percentages, and the like are by weight.

EXAMPLE l Test of Acetamiprid Transferal and Resultant Mortality to Termite Population

This test was conducted in petri dishes containing moist (10% moisture) Sparks, Georgia fine sandy soil. For each of the four reps, 10 termites were sprayed with the test rate solution of acetamiprid 70WP in water. Once dry, the 10 treated donor termites were placed into a petri dish containing moist soil and 10 recipient termites_*- Mortality was graded daily for 10 days. Test rates used were: 0 ppm, 125 ppm, 250 ppm and 500 ppm in water. Both Reticulitermes flavipes and Coptotermes formosanus were evaluated in this test. The following results were obtained:

Table 1

Acetamiprid Transfer in Reticulitermes flavipes

10 termites treated with direct application then placed with 10 untreated

Rate of Mortality Mortality Mortality Mortality Mortality Mortality Mortality Mortality Appln. Rate @ l Rate ® 2 Rate ® 3 Rate ® 6 Rate ® 7 Rate ® S Rate ® 9 Rate @ 10 (PPM) day days days days days days (%) days days (%) (%)) (%) (%) (%) (%) (%)

125 0 29 50 79 82 89 91 97

250 0 27 40 56 69 75 89 91

500 12.5 37 45 74 79 85 87 94 untreated 1 1 1 1 1 2 4 4 Table 2 Acetamiprid Transfer in Coptotermes formosanus

10 termites treated with direct application then placed with 10 untreated

Rate of Mortality Mortality Mortality Mortality Mortality Mortality Mortality Mortality Appln. Rate @ l Rate ® 2 Rate ® 3 Rate ® 6 Rate ® 7 Rate ® 8 Rate ® 9 Rate @ 10 (PPM) day days days days days days (%) days days (%) (%)) (%) (°/<0 (%) (%) (%)

125 0 5 30 5δ 69 71 77 81

250 2 27 39 60 79 81 91 94

500 11 39 59 71 80 87 90 94 untreated 0 0 0 0 0 0 0 0

EXAMPLE 2 Field Test of Effectiveness in Controlling Termite Populations

Subterranean termite infested structures were selected for the trials on the basis of significant active infestation (ie to represent a termite population). Significant active infestation was determined by the presence of between 1 and 20 established mud tubes on the structures. The termite-infested structures were all located on monolithic slabs, so the ingress and egress of termites was limited to the perimeter around the slab and bath traps (pipe access points in the slab foundation). Both Coptotermes and Reticuliterm.es termite genera were represented in the testing. Soil types around and under the monolithic slabs included clay, loam, and silt.

The structures were treated using a full exterior treatment where the outside of the monolithic slab was trenched and the acetamiprid was applied in the trench. Concrete surfaces (patio, driveway, sidewalk, steps) adjacent to the monolithic slab were also drilled and treated with acetamiprid. All bath traps were treated with acetamiprid. All treatment points constituted areas (loci) remote from the termite population. Termites passed through these areas to gain ingress and egress to the termite population. As the termites passed through the treated areas, they came in contact with the acetamiprid and transferred the active ingredient to other members of the population that had not come into direct contact with acetamiprid.

After treatment, inspections were performed until the termite population within the structure was controlled based upon lack of termite activity in the mud tubes. Visual inspections were augmented through the use of moisture meters and Termatrac motion detection equipment to confirm the removal of live termites from the test structures. The following results were obtained:

Table 3 - Field Trial Data on Controlling Termite Populations Using a Remote

Application of Acetamiprid

While this invention has been described with an emphasis upon preferred embodiments, it will be understood by those of ordinary skill in the art that variations of the preferred embodiments may be used and that it is intended that the invention may be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications encompassed within the spirit and scope of the invention as defined by the following claims.

Claims

What is claimed is:

1. A method for controlling a termite population comprising applying a termiticidally effective amount of acetamiprid to a termite from said population at a locus remote from said termite population.

2. The method according to claim 1, wherein said locus is selected from a termite-infested structure, a structure that is expected to be termite-infested, a bait station, a monitor station, a crop, a tree crop or a location adjacent to said structure, crop, tree crop or station.

3. The method according to claim 1, wherein said acetamiprid is applied as a formulation wherein the acetamiprid is present in a concentration of from 0.001% by weight to 1% by weight based upon the total weight of all components in the formulation.

4. The method according to claim 3, wherein said acetamiprid is present in a concentration of from 0.01% by weight to 0.25% by weight based upon the total weight of all components in the formulation.