EP2914572A1 - Method of monitoring and/or controlling thysanoptera - Google Patents

Abstract

The present invention provides a method of monitoring or controlling Thysanoptera (hereafter thrips) using a behaviour-modifying compound of Formula (1), wherein Formula (1) is: where R¹ is a C₂-C₈ straight or branched alkenyl group and the * denotes a stereocentre. Suitably, the method involves providing the behaviour-modifying compound at a pre- determined location. Typically the behaviour-modifying compound is released or broadcast within an area infested (or potentially infested) by thrips. This can be achieved by using a lure or other release device comprising a compound of Formula (1), for example to attract the thrips to a trap.

Description

METHOD OF MONITORING AND/OR CONTROLLING THYSANOPTERA

FIELD OF THE INVENTION

The present invention relates to a method of monitoring or controlling Thysanoptera (thrips), particularly but not exclusively Thripinae, particularly Thrips palmi (Karny). INTRODUCTION

Spoilage of cultivated plants or crops by insect pests is a widespread problem. Insects are recognised to cause direct damage by eating the plants or crops and also by laying eggs therein. Additionally insects often carry transferable diseases that cause damage of plants or crops. The order Thysanoptera (thrips) is a group of insects that is recognised as causing damage to a wide range of cultivated crops. Some thrips are a pest of a particular crop, e.g. avocado thrips are a pest to avocado crops, whereas some species are a pest to a wide range of crops. Thrips cause damage to crops by feeding upon the crops and laying their eggs therein. Their feeding method comprises penetrating parts of the plant and sucking out the liquid contents, thus causing aesthetically unappealing scarring and stunting the growth of the crop. The presence of insects alone or small feeding marks can make ornamental crops unsaleable. Some thrips spread plant viruses, which can cause considerable damage to many crops.

Thrips are commonly active within enclosed parts of the crop, such as flower buds and leaf buds. Thus commonly the damage caused by thrips, in the form of direct damage such as feeding and in the form of indirect damage such as transmission of a virus, occurs before the thrips themselves are observed. For crops such as commercially harvested flowering plants the management of thrips is a particularly acute problem because the thrips damage is sometimes only observed in the late stages of flower development when the bud finally opens. Thrips are also a problem because they breed rapidly and large pest populations can build up very quickly if unchecked.

Amongst the many known species of thrips, there is believed to be a particularly serious and imminent threat to EU horticulture from Thrips palmi, (henceforth T palmi) a member of the Thripinae sub-family. Commonly known as the "melon thrips", the pest targets a large range of crops including many crops found in the EU (Cannon et al., 2007a). The significant danger posed by the pest is reflected in its presence on the A1 list of species recommended for regulation as quarantine pests by the European and Mediterranean Plant Protection Organisation, and its presence in Annex IAI of the EC Plant Health Directive (2000/29/EC), which specifies that the pest must be eradicated wherever it appears in the EU.

T. pa/m/^' outbreaks have already occurred in numerous places across the world, such as Japan and Australia. During the post-invasion phase in Japan by T. palmi, over 9000 ha of greenhouse vegetable crops were affected with 30% of aubergine crops being lost (Nagai, 1993). T. palmi remains a major pest in several greenhouse and outdoor crops in Japan (Kawai, 2001 ; Yano, 2004). Following the arrival of T. palmi in the Northern Territory of Australia in 1988, horticultural exports dropped by 71 % from€3.0m to€1.1 m as a result of crop losses and quarantine restrictions. Furthermore, the pest is regularly intercepted at EU ports and outbreaks in the Netherlands (1988-1998) and the UK (2000-2001) were eradicated only with difficulty (Cannon et al. 2007b). Large losses are expected when such alien pests arrive because existing control measures are not effective.

Thus, there exists a need to develop effective methods for controlling and monitoring thrips, in particular, for controlling and monitoring T. palmi.

One method of controlling insects is the direct application of pest control agents/pesticides to the plant/crop. However, as the pest control agents/pesticides used are commonly toxic to other animals their use is becoming increasingly less acceptable on environmental and ecological grounds. Also there is the problem of the triggering of undesirable reactions, such as poisoning or allergies, for agricultural and horticultural workers. Many consumers are reluctant to purchase edible crops that have been treated with pesticides, because of fears of adverse effects on their health from pesticide residues.

Thrips are particularly difficult to control with insecticides because they retreat into minute recesses on the plant where insecticides are less likely to reach them and because the main pest species have high levels of insecticide resistance. Additionally pesticides applied to crops are perceived to be a poor solution to the problem of thrips since the pesticides used are normally detrimental to the population of beneficial arthropods that prey upon the thrips and other insect and mite pests on the crop.

An alternative method of controlling insects is to use biological control agents. Biological control agents such as predatory mites or fungal pathogens are sometimes used to control thrips, but they are not always reliable and they are not very effective on some crops. A further method for controlling insects involves the use of insect traps. The use of traps in the vicinity of the crop that contain a semiochemical (such as an aggregation pheromone) and a pest control agent (such as glue, insecticide, or biocide) is becoming increasingly widespread. The traps may be selective in attracting one sex (usually the male) of the insect concerned so as to remove them from the population and hence control population growth. Alternatively the traps may be more general in their operation.

The general release of an attracting sex pheromone is also sometimes used as a control method. The released sex pheromone "confuses" the sex that is attracted so that it cannot locate a mate. This disruption of the mating process slows down or stops the build-up of the pest population.

The identification and characterisation of semiochemicals suitable for controlling and monitoring thrips is extremely challenging.

In sunny conditions, male thrips form mating aggregations whilst producing aggregation pheromones which cause numbers of males and females in the area to grow. However, the male thrips do not store aggregation pheromones, and instead produce them when required in very small (picogram) quantities. Moreover, pheromones and other semiochemicals differ from species to species, meaning that compounds which affect the behaviour of one species are most likely to have no effect upon other species, or possibly an entirely different effect.

Semiochemical-based control methods have been developed for some species of thrips, particularly the western flower thrips (Frankliniella occidentalis (Pergande)). For example, PCT publication WO 03/055309 presents examples showing that isobornyl valerate, isobornyl 2-methylbutanoate, isobornyl pivalate and lavandulyl valerate effectively attract western flower thrips, whereas lavandulyl acetate, neryl acetate and neryl formate do not. US 2006/0041018 additionally shows that neryl (S)-2-methylbutanoate acts as an attractant of western flower thrips. In addition, semiochemical-based products are commercially available for western flower thrips. One such product, is marketed under the name "Thripline ams" by Syngenta Bioline. This product is based on neryl (S)-2-methylbutanoate, which has been discovered to be an aggregation pheromone released by male western flower thrips, increasing trap catches of males and females in glasshouses. Another semiochemical-based product targeting western flower thrips, as well as other species, is offered by Koppert B.V. under the name "LUREM-TR", and methyl isonicotinate is the current active ingredient.

However, there is still a need to identify compounds having specificity for other species of thrips. In particular, given the harm already caused around the world by T. palmi, as well as the considerable potential for harm if the species were to become established in the EU, there is a need for an improved approach to the monitoring and control of this species.

SUMMARY OF THE INVENTION

In a first aspect, the present invention provides a method of monitoring or controlling Thysanoptera (hereafter thrips) using a behaviour-modifying compound of Formula (1), wherein Formula (1) is:

where R is a C₂-C₈ straight or branched alkenyl group and the * denotes a stereocentre.

By "alkenyl" group we mean a univalent aliphatic hydrocarbon radical having at least one carbon-carbon double bond. All structural isomers (including positional isomers) and stereoisomers (including cis and trans (Zand E) isomers) are encompassed within the term "alkenyl". For example, the double bond may be at the terminal position of the alkenyl moiety, or may occur at some other part of the alkenyl moiety.

A "Cn alkenyl" group means an alkenyl group having n carbon atoms.

The present inventors have found through extensive research that compounds of Formula (1) are particularly effective in replicating or mimicking the effects of a natural thrips pheromone and thus may be effectively used in methods of monitoring or controlling the behaviour of thrips. In particular, the inventors have found that the compounds are aggregation pheromones (i.e., attractants) of thrips, in particular, T. palmi. The compounds attract both male and female thrips. Importantly, the present invention does not rely on any toxic qualities of the compound of Formula (1) but rather on the modification of thrips behaviour for its effect.

Although we refer to "monitoring or controlling" of thrips, it should be appreciated that these activities are not mutually exclusive: methods of monitoring can be used as methods of controlling and vice versa, i.e., the expression should be read as "monitoring and / or controlling". Furthermore, it should be clear that the word "control" covers a number of different activities. For example, controlling thrips includes activities such as attracting, confusing, killing and / or modifying the behaviour of thrips. The word "monitor" is also intended to cover a number of activities, including determining the number of thrips in a region and / or identifying the species of thrips in a region, including identifying the relative changes in the numbers of thrips in a region.

The method of monitoring or controlling thrips can be carried out in several ways. Suitably, the method involves providing the behaviour-modifying compound at a pre-determined location. Typically the behaviour-modifying compound is released or broadcast within an area infested (or potentially infested) by thrips. This can be achieved by using a lure or other release device comprising a compound of Formula (1), for example to attract the thrips to a trap. Suitable release devices and traps are discussed below.

The ability to monitor the type (i.e., species) and number of thrips is an important advantage in establishing the threat posed by thrips and it can provide an early warning as to rising thrips numbers. Improved monitoring using a compound according to Formula (1) as an attractant or pheromone can therefore lead to more effective treatment of thrips, for example by early treatment.

In embodiments of the invention the method is for monitoring male and / or female thrips. Suitably, the method is for monitoring adult male and / or adult female thrips. Suitably, the method may be used to gauge the population density of thrips in a particular area from analysis of the number and / or sex of the thrips. Based on the number of thrips monitored a decision may then be made as to what further action, if any, is required. The level of monitoring or controlling may be selected so that as high a portion of thrips is removed from the population as possible. When female thrips are monitored or controlled, management of the overall thrips population can be achieved by reducing the number of female thrips. It has been observed that when the method of the invention is used to monitor female thrips it is particularly efficacious as with removal of a portion of the number of egg-laying females from the thrips population not only is the damage caused by females laying eggs in a crop to be protected quickly reduced but also population growth is quickly curbed with its associated advantages in terms of reduced damage.

When male thrips are monitored or controlled management of the overall thrips population can be achieved as the female thrips are not fertilised. Unfertilised females then produce only male thrips thus the number of females in the next generation is reduced and so population increase is curbed.

Preferably, the method uses a compound where R is a branched alkenyl group.

Preferably, the method uses a compound where R is C₂ to C₇, more preferably C₃ to C₇, more preferably C₃ to C₆, more preferably C₃ to C₅, more preferably C₃ to C₄, most preferably C₄.

Most preferably, the method uses a compound where R is a branched C₄ alkenyl group. In embodiments R comprises one carbon-carbon double bond.

Preferably R comprises a carbon-carbon double bond at a terminal position of the alkenyl group.

Preferably the behaviour-modifying compound is not (S)-lavandulyl senecioate (which is also known by the systematic name of (S)-lavandulyl 3-methyl-2-butenoate).

The stereocentre marked with a "*" in Formula (1) can take either an (R) configuration or an (S) configuration, leading to molecules referred to herein as the "(R) stereoisomer" and "(S) stereoisomer". In some embodiments the compound used in methods of the present invention is part of a racemic mixture of (R) and (S) stereoisomers. In other embodiments, the compound is predominantly present in one stereoisomeric form. In preferred

embodiments the compound is present in a composition where there is an excess of the (R) stereoisomer relative to the (S) stereoisomer. For example, the amount of the (R) stereoisomer as a percentage of the total amount of the compound of Formula (1 ) present may be greater than 60%, greater than 70%, or greater than 80%. Preferably this percentage is greater than 90%, more preferably greater than 95% and most preferably about 100%. Differently stated, it is preferred that the percentage enantiomeric excess of the (R) stereoisomer is greater than 0%, more preferably greater than 25%, more preferably greater than 50%, still more preferably greater than 75%, and most preferably about 100%. Of course, it will be appreciated that when the R group also contains a stereocentre then diastereomers are also possible.

Especially preferred are methods using lavandulyl 3-methyl-3-butenoate, which is a compound according to Formula (2):

Most preferred are methods using (/^-lavandulyl 3-methyl-3-butenoate, which is a compound of Formula (3):

The present inventors have found that the compound shown in Formula (3) is released naturally from T. palmi, a member of the Thripinae sub-family of thrips. Thus, methods using a compound of Formula (3) allow replication of the effects of a natural thrips pheromone. The compound is produced in extremely small amounts by the male insects, and thus the identification and characterisation of the molecule presented considerable technical challenges and hurdles.

The compound shares some general structural similarities with neryl (S)-2-methylbutanoate, an aggregation pheromone of western flower thrips. This, and its presence only in the males and not the females, provides strong evidence that the compound of Formula (3) is an aggregation pheromone for T. palmi. Furthermore, experimental data presented below show that the compound significantly improves trap catches of T. palmi. In other words, the compound is an attractant for T. palmi. Thus, in preferred embodiments, the methods of the present invention are for monitoring or controlling T. palmi.

In addition, experimental data presented below show that the compound also significantly improves trap catches of Frankliniella intonsa (henceforth F. intonsa), another member of the Thripinae sub-family of thrips. Thus, in other preferred embodiments, the methods of the present invention are for monitoring or controlling F. intonsa. More generally, it is preferred that methods of the present invention are for monitoring or controlling thrips from the family Thripidae, most preferably from the sub-family Thripinae.

In some embodiments the behaviour-modifying compound is a thrips aggregation pheromone, i.e., an attractant. Suitably the compound attracts both males and females. The use of a behaviour-modifying compound of Formula (1) as an attractant preferably improves the sensitivity of traps for thrips, particularly at low levels of infestation or in easily damaged crops in glasshouses. In addition or alternatively to attracting thrips to a trap, the compound can be used to attract thrips away from a crop. Methods in which the compound is used as an attractant allow growers to identify the pest and introduce additional control measures before pest populations reach economically damaging levels. As a result of improved monitoring and appropriate early control measures, reduced amounts of conventional pesticides may be needed, with concomitant savings in cost to the grower and burden to the environment. This is particularly appealing since there is current interest and legislative pressure to reduce the number of active ingredients used in pesticides and remove large numbers of insecticides from the market.

In some embodiments, the behaviour-modifying compound is used as a confusant. By providing confusant compounds in an area infested (or potentially infested) with thrips, the effect of the natural pheromones released by the thrips may be overcome or "masked" such that the thrips become "confused". For example, a "cloud" of the compound may be provided around a thrips such that the thrips is unable to find the source of the compound. In this way, the thrips may move in a random way.

Additionally or alternatively to the behaviour-modifying compound acting as an attractant or a confusant, suitably the compound can increase the activity of a thrips so as to increase the likelihood of the thrips encountering a thrips killing device or thrips monitoring device, or a pesticide or biological control agent.

The present inventors have found that the behaviour-modifying effect of compounds of Formula (1) can be achieved for extended periods of time by controlling the release of the compounds into the air. This can be achieved by using a release device. Thus, suitably, the compound of Formula (1) is provided in a release device. A "release device" is adapted to release a pheromone such as compounds of Formula (1) into the air. In some embodiments the release device actively releases the compound into the air (e.g., spraying the compound into the air). In other embodiments the release device passively releases the compounds into the air (e.g., by evaporation). In some embodiments the release device can have a mechanism for releasing the compound into the air and also allow compounds to be passively released. Thus, in embodiments the compound can be actively or passively dispersed or broadcast in a particular area

It is irrelevant whether or not the released compound has the effect of attracting (luring) thrips to the release device. Thus, a release device includes arrangements wherein the compound is released into the air for the purposes of changing the behaviour of thrips, for example by confusing them or randomising their movements, as well as arrangements wherein the compounds are released such that a thrips is attracted to and lands on the release device. Several types of release device are possible.

For example, suitably, the release device comprises a matrix and the compound of Formula (1) is dispersed within the matrix. Suitably the matrix is porous. Preferably the matrix is made of rubber, preferably natural rubber. However, the matrix may be made of materials other than rubber, for example plastics material such as polymers. Suitably, the matrix is in the form of a septum, preferably a rubber septum, such as those available from International Pheromone Systems Ltd.

In another arrangement, the release device may be a laminate.

In another preferred arrangement, the release device is a container having walls that are permeable to compounds of Formula (1), wherein the container contains a compound of Formula (1). The container therefore provides a reservoir of the behaviour-modifying compound and a means for controllably releasing the compound, i.e. via the permeable walls. Suitably the walls are flexible. Suitably the container is closed (or closable, for example with a closable opening) such that the compound can leave the container only via the walls. In preferred arrangements, the flexible walls are made from a plastics material, preferably polyethylene. In particularly preferred embodiments the container is a bag or sachet.

In a further preferred arrangement the release device is a container, preferably a tube, which contains the behaviour-modifying compound, wherein the container comprises an orifice through which the compound can be released from the container. Suitably the container is closed (or closable, for example with a closable opening) such that the compound can leave the container only via an orifice. The diameter of the orifice can be adjusted to control the rate of release (typically via evaporation) of the compound. Suitable containers are Eppendorf tubes (centrifuge tubes) which have been adapted by providing an orifice in one of the walls of the tube.

In a further preferred arrangement, the release device is a sprayer. The sprayer allows an area of interest to be sprayed with the behaviour-modifying compound. For example, the sprayer may be a backpack sprayer or a hand held plant sprayer. As another example, the sprayer may take the form of an elongate conduit with several spraying nozzles positioned along the conduit for releasing the behaviour-modifying compound. Suitably, the sprayer may be an aerosol sprayer. For example, the sprayer may be an aerosol can containing the behaviour-modifying compound and a propellant. In this way, the behaviour-modifying compound may be applied to a surface where it subsequently evaporates. Alternatively or additionally, the compound may be sprayed directly into the air.

Generally in order to produce or mimic the effect of a single thrips the release device is configured to produce or release a compound of Formula (1) in an amount which is at least and more preferably a multiple of the amount of pheromone which would be released by a single thrips. For example, suitably the release device releases an amount that is at least twice the amount produced by a single thrips, preferably at least four times, more preferably at least eight times, more preferably at least twenty times, and more preferably still at least eighty times the amount produced by a single thrips.

Generally, it is preferred that the release rate is such that the concentration of behaviour- modifying compound in the immediate vicinity of the release device is greater than that produced by a single thrips, preferably at least four times, more preferably at least eight times, more preferably at least twenty times, and more preferably still at least eighty times the amount produced by a single thrips.

The lower limit for the release rate from the release device can be, for example, 1 picogram per hour, 10 picograms per hour, 100 picograms per hour, 1000 picograms per hour or 2000 picograms per hour.

The upper limit for the release rate is not particularly limited but can be, for example, 1.5 ^χ 10⁶ picograms per hour, 1 ^χ 10⁶ picograms per hour, 7.5 ^χ 10⁵ picograms per hour, 5 ^χ 10⁵ picograms per hour, 1 ^χ 10⁵ picograms per hour, 5 ^χ 10⁴ picograms per hour or 1 ^χ 10⁴ picograms per hour.

It will be appreciated that the lower and upper limits for the release rate can be combined together, and the present invention is intended to cover all such combinations. However, preferred release rates include 1 to 1 ^χ 10 picograms per hour, more preferably 1000 to 5 ^χ 10⁵ picograms per hour.

In embodiments of the release device in which the behaviour-modifying compound is passively released, the release suitably occurs from a surface of the release device having an associated surface area. For example, in the case of a matrix or laminate impregnated with the compound, the compound is released from the surface impregnated with the compound. In addition, in the case of a container which releases the compound through permeable walls or an orifice the compound is released from a surface in contact with the air. In such embodiments, the lower limit for the release rate of the compound, normalised to the area from which the compound is emitted, is preferably 0.001 picograms per hour per cm² of surface area, 0.01 picograms per hour per cm², 0.1 picograms per hour per cm², 1 picogram per hour per cm², or 10 picograms per hour per cm². In such embodiments, the upper limit for the release rate of the compound, normalised to the area from which the compound is emitted, can be 10000 picograms per hour per cm² of surface area, 5000 picograms per hour per cm², 2500 picograms per hour per cm², or 1000 picograms per hour per cm².

It will be appreciated that the lower and upper limits for the release rate normalised to the area from which the compound is emitted can be combined together, and the present invention is intended to cover all such combinations. In embodiments, there may be at least one release device per 10 m² of crop area, 50 m² of crop area, 100 m² of crop area or 200 m² of crop area.

In enclosed crop growing areas, such as greenhouses, there may be at least one release device per 30 m³ of enclosed volume, 150 m³ of enclosed volume, 300 m³ of enclosed volume, 600 m³ of enclosed volume or 1500 m³ of enclosed volume. Furthermore, it will be appreciated that the preferred release rate may be dependent upon the way in which the behaviour-modifying compound is being used, e.g., whether it is being used as an attractant, to increase activity of thrips, or as a confusant. Furthermore, it will be appreciated that the release rate from sprayers, in which the compound is actively released from the release device (as opposed to passively by, for example, evaporation) is determined by the user to suit the area in which the behaviour-modifying compound is released. In embodiments in which the behaviour-modifying compound is an attractant, the release device acts as a lure. A large number of lures are available commercially (for example, from Russell IPM).

In methods for monitoring thrips, the thrips can be lured to a thrips monitoring device. As stated above, the methods of monitoring or controlling thrips that form part of the present invention include methods of killing thrips. This can be achieved by luring the thrips to a thrips killing device.

In these embodiments the compound is not acting as a pesticide or other toxic agent, but as an attractant and is suitably associated with a thrips killing device (e.g. a sticky trap or water trap). Additionally or alternatively to the compound attracting the thrips directly to a thrips killing device, suitably the compound can increase the activity of a thrips so as to increase the likelihood of the thrips encountering a thrips killing device.

By utilising the compound in this way, it is possible to control thrips, for example to limit the population of thrips in a particular crop growing area such as a glasshouse or polytunnel. Thus, the release device is preferably associated with a thrips killing device for immobilising and / or killing the thrips.

In this way, a release device associated with a thrips killing device may be used to attract thrips and then immobilise or kill the thrips so as to remove the thrips from a crop growing area. Suitably the thrips killing device is a trap.

In a preferred embodiment, the trap comprises a substrate and a sticky adhesive coating applied to the substrate. Suitably the substrate is in the form of a sheet. Typically the sheet is rectangular. Preferably the sheet has dimensions of about 5 to 10 cm by about 10 to 25 cm, although other dimensions and shapes are possible. The sticky adhesive coating may be applied to just one side of the sheet, or to both sides of the sheet. The substrate may also be in the form of an elongate strip. For example, the sheet may be in the form of an elongate strip that can extend along, around or across a portion of the growing area. The elongate strip may be sold on a roll, from which it may be unwound. The trap may also comprise a mesh layer, for example having a mesh grid size of approximately 5mm x 5mm, which can assist handling. Preferably the substrate comprises a plastics material, but it can also be made of paper or other materials. Preferably the sticky adhesive coating is non-toxic. Such adhesive coatings or "insect glues" are known and are typically polymeric. Traps of this sort are known as sticky traps. The sticky trap may be a wet sticky trap, or may be a dry sticky trap such as a Takitrap® (available from Syngenta Bioline).

In a preferred arrangement of this sort of trap, the release device is integral with the trap. Indeed the trap is preferably also the release device. Thus, suitably the substrate is porous to allow impregnation of the behaviour-modifying compound. Alternatively or additionally, the behaviour-modifying compound can be incorporated into the adhesive coating, e.g. by adding the compound directly to the adhesive coating or by formulating the adhesive with the compound prior to application to the substrate. Alternatively or additionally, the behaviour- modifying compound can be coated onto the substrate before an adhesive coating is applied.

Thus, in such traps/release devices, one or both of the substrate and the sticky adhesive layer can act as a matrix in which the behaviour-modifying compound is dispersed and from which it can evaporate under typical glasshouse, polytunnel, or open field conditions.

In other preferred embodiments the release device is not integral to the trap, and is instead a separate part.

In a second preferred embodiment, the trap comprises a container which in use is filled with water, or a mixture of water and detergent. When a thrips enters the trap, it will fall into the water-filled container and become immobilised on contact with the water. This type of trap is commonly known as a water trap.

In this embodiment, the release device is suspended above the container and / or attached to the container. Suitably the trap includes attachment means to which the release device can be attached. In this way, thrips are attracted to the trap and brought into proximity with the water, thereby increasing the chances of immobilising the thrips. This sort of trap is particularly preferred because large numbers of thrips can be trapped. It will be appreciated that a water trap can also be made in which the release device is integral with the trap.

As thrips are attracted to certain colours it is preferred that the trap and/or release device is coloured to attract thrips. Most preferably the trap and/or release device is coloured blue, white or yellow or combinations of these and/or other colours. In this connection it is noted that the use of coloured release devices is described in the paper Journal of Applied Entomology, 107, 136-140 (H. F. Br0dsgaard), in which a sheet having a colour close to Pantone® 279 (a shade of blue) was found to be the most attractive for thrips.

Additionally or alternatively to the behaviour-modifying compound attracting thrips to a thrips killing device, the method of killing thrips includes providing a pesticide and / or biological control agent and attracting thrips to the pesticide and / or biological control agent. For example, the behaviour-modifying compound may be used to attract thrips to a pesticide or biological control agent which has been applied to a surface, e.g., the surface of a plant. Alternatively or additionally, to the compound attracting the thrips directly to a pesticide and / or biological control agent, suitably the compound can increase the activity of thrips so as to increase the likelihood of the thrips encountering the pesticide and / or biological control agent.

Suitably, the pesticide can be any one or more known insecticides. Preferably the insecticide is selected from spinosad, azadirachtin, imidacloprid, and thiacloprid. For example, commercially available products such as Neemix™ and Bioneem™ (which contain azadirachtin) and / or Success, SpinTor, Spinoace, Boomerang, Laser, Extinosad, Conserve SC and Entrust (which contain spinosad) can be used. Other insecticides (and their commercially available formulation) include bifenthrin (Talstar 10WP), cyfluthrin (Tempo 2E; Decathlon 20WP ), d-phenothrin (Sumithrin 2EC; PT 1400), fenpropathrin (Tame 2.4EC), fluvalinate (Mavrik 2F), permethrin (Pounce), resmethrin (SBP-1382; PT 1200), pyrethrum (Pyrenone; PT 1 100; PT 1600A), fenvalerate (Pydrin), lambda-cyhalothrin (Scimitar 10WP), acephate (PT 1300; Orthene TTO), naled (Dibrom), sulfotepp (Plantfume 103), chlorpyrifos (Dursban 50WP, Duraguard), diazinon (PT 1500R Knox Out), methiocarb (PT 1700), endosulfan (Thiodan 2EC, 3EC, 50WP), kinoprene (Enstar 5E), fenoxycarb (Preclude, Precision), pyriproxyfen (Distance), oxythroquinox (Joust), abamectin (Avid 0.15EC), pymetrozine (Endeavor 50WG) and pyridaben (Sammite 75SP).

Suitably, the pesticide can be a biopesticide; that is, a pesticide based on a micro-organism or natural product. Suitable biopesticides include, for example, fungal pathogens such as Beauveria, Naturalis-O® and Naturalis-L®.

Suitably, the biological control agent can be a predatory bug or mite. For example, the method may involve the use of Orius spp., Amblyseius cucumeris, Amblyseius

montdorensis, Amblyseius swirskii, Typhlodromips montdorensis, Euseius ovalis or

Hypoaspis species. Typically, the behaviour-modifying compound is provided in a composition. Thus, in respect of each of the methods referred to above, the compound may be present as a composition comprising the compound.

Preferably in the methods described herein the behaviour-modifying compound is provided in a thrips behaviour-modifying composition, wherein the thrips behaviour-modifying composition comprises, preferably substantially consists of, more preferably consists essentially of and most preferably consists of the behaviour-modifying compound.

Alternatively, the behaviour-modifying compound can be provided as a composition comprising a pesticide. Suitably, the pesticide can be any one or more known insecticides. Preferably the insecticide is selected from spinosad, azadirachtin, imidacloprid, and thiacloprid. For example, commercially available products such as Neemix™ and Bioneem™ (which contain azadirachtin) and / or Success, SpinTor, Spinoace, Boomerang, Laser, Extinosad, Conserve SC and Entrust (which contain spinosad) can be used. Other insecticides (and their commercially available formulation) include bifenthrin (Talstar 10WP), cyfluthrin (Tempo 2E; Decathlon 20WP ), d-phenothrin (Sumithrin 2EC; PT 1400), fenpropathrin (Tame 2.4EC), fluvalinate (Mavrik 2F), permethrin (Pounce), resmethrin (SBP-1382; PT 1200), pyrethrum (Pyrenone; PT 1 100; PT 1600A), fenvalerate (Pydrin), lambda-cyhalothrin (Scimitar 10WP), acephate (PT 1300; Orthene TTO), naled (Dibrom), sulfotepp (Plantfume 103), chlorpyrifos (Dursban 50WP, Duraguard), diazinon (PT 1500R Knox Out), methiocarb (PT 1700), endosulfan (Thiodan 2EC, 3EC, 50WP), kinoprene (Enstar 5E), fenoxycarb (Preclude, Precision), pyriproxyfen (Distance), oxythroquinox (Joust), abamectin (Avid 0.15EC), pymetrozine (Endeavor 50WG) and pyridaben (Sammite 75SP).

Suitably, the pesticide can be a biopesticide. The biopesticide may be, for example, fungal pathogens such as Beauveria, Naturalis-O® and Naturalis-L®.

When formulated as a composition for killing thrips in combination with a pesticide, the behaviour-modifying compound is suitably present at a concentration of <1 wt% based on the total weight of the composition. Preferably the behaviour-modifying compound is present at a concentration of <0.5 wt%, more preferably <0.1 wt%, more preferably <0.05 wt%, and most preferably <0.01 wt%. Preferably the behaviour-modifying compound is present in an amount of at least 10^"4 wt%. Suitably the composition is a liquid. Alternatively, the composition is a solid form, such as a powder.

Embodiments of the method of the present invention may be used to monitor or control the population of thrips, particularly on members of the plant families Cucurbitaceae and Solanaceae. More generally, the methods can be used to monitor or control the population of thrips on cultivated flower crops (e.g., chrysanthemums and roses), vegetables, fruits and other crops. For example, the method may be used for monitoring or controlling the population of thrips on aubergine (eggplant, brinjal), avocado, bean, Benincasa hispida, cabbage, cantaloupe, Capsicum annum, carnation, chilli, Chinese cabbage,

chrysanthemum, citrus, cotton, cowpea, cucumber, Cucurbita spp., Cyclamen, Ficus, hibiscus, lettuce, mango, melon, okra, onion, Orchidaceae, pea, peach, sweet pepper, plum, potato, pumpkin, rice, roses, sesame, soyabean, squash, sunflowers, tobacco, or watermelon.

Preferably the method of monitoring or controlling thrips includes attracting thrips in a crop growing area.

Suitably the methods of the present invention take place in an enclosed crop growing area such as a glasshouse or polytunnel. Alternatively, the methods of the present invention take place in open field conditions.

The method of monitoring or controlling thrips suitably includes attracting thrips associated with a crop after the crop has been harvested.

In addition, the method of monitoring or controlling thrips may include attracting thrips during crop transport or storage. This may be before or after the crop has been harvested. In particular, the method may be used to monitor or control thrips as a crop enters a country, such as at a port. This type of monitoring or controlling can help to prevent the spread of thrips between different geographical locations. In particular, the method may be used to monitor or control thrips in a quarantine area or facility.

In embodiments of the present invention, the behaviour-modifying compound may be used as part of a mixture of behaviour-modifying compounds. This mixture may include, for example, other semiochemicals such as pheromones, allomones, kairomones, attractants and repellents. The mixture of behaviour-modifying compounds may include a behaviour- modifying compound of Formula (1) in conjunction with one or more other thrips behaviour- modifying compounds, or in conjunction with one or more behaviour-modifying compounds that target other insects.

As an example of such a mixture, the mixture may contain a behaviour-modifying compound of Formula (1) above in conjunction with neryl (S)-2-methylbutanoate (the active ingredient of "Thripline ams" by Syngenta Bioline) and / or methyl isonicotinate (the current active ingredient of "LUREM-TR" by Koppert B.V.). Advantageously, the use of a mixture of behaviour-modifying compounds may increase the attraction, confusion or activity of thrips compared to the use of the behaviour-modifying compound alone. Also, the use of a mixture may allow other unwanted pests or beneficial predators to be attracted or repelled. In a further aspect, the present invention provides the use of a behaviour-modifying compound according to any one of the formulae above in a method of monitoring thrips.

In a further aspect, the present invention provides the use of a behaviour-modifying compound according to any one of the formulae above in a method of controlling thrips.

In a further aspect, the present invention provides the use of a behaviour-modifying compound according to any one of the formulae above in a method of killing thrips.

In a further aspect, the present invention provides the use of a behaviour-modifying compound according to any one of the formulae above in a method of modifying the behaviour of thrips.

In a further aspect, the present invention provides the use of a behaviour-modifying compound according to any one of the formulae above in a method of treating a crop for thrips infestation.

In particular, in one such further aspect, the present invention provides a method of attracting thrips to a predetermined location, the method comprising the step of providing a behaviour-modifying compound according to any one of the formulae above at the predetermined location. Suitably the compound is provided in a release device and the release device is located at the predetermined location.

In a further aspect, the present invention provides a method of monitoring thrips, the method comprising the step of providing a thrips monitoring device and a behaviour-modifying compound according to any one of the formulae above associated with the thrips monitoring device. Suitably the compound is provided in a release device, which is preferably attached to the thrips monitoring device. Preferably the thrips monitoring device is a trap, suitably a sticky trap.

In a further aspect, the present invention provides a method of killing thrips, the method comprising the step of providing a thrips killing device and a behaviour-modifying compound according to any one of the formulae above associated with the thrips killing device. Suitably the compound is provided in a release device, which is preferably attached to the thrips killing device. Preferably the thrips killing device is a trap, suitably a sticky trap or mass trap, for example a water trap, or other mass trapping device.

In a further aspect, the present invention provides a method of killing thrips, the method comprising the step of providing a pesticide or biological control agent and a behaviour- modifying compound according to any one of the formulae above associated with the pesticide or biological control agent.

In a further aspect, the present invention provides a method of modifying the behaviour of thrips, the method comprising the step of providing a release device comprising a behaviour- modifying compound according to any one of the formulae above.

The present invention is also concerned with compositions for killing thrips. A composition for killing thrips suitably comprises a pesticide. The effectiveness of such a composition may be increased by including a behaviour-modifying compound according to the formulae above as an attractant, to encourage the thrips to contact the composition and hence the pesticide. Thus, in a further aspect, the present invention provides a composition for killing thrips, the composition comprising a behaviour-modifying compound according to any one of the formulae above and a pesticide. Preferred pesticides and concentrations of the behaviour- modifying compound have been discussed above. The pesticide may comprise an insecticide and / or biopesticide as defined above. Such compositions can be used to treat a crop, for example by direct application of the composition to the crop. This may be achieved by spraying the crop with the composition.

In a yet further aspect, the present invention provides a method of treating a plant or crop comprising the step of applying a composition to the plant or crop, wherein the composition comprises an insecticide and a behaviour-modifying compound according to any one of the formulae above. The present invention is also concerned with release devices, thrips killing devices and thrips monitoring devices which include a behaviour-modifying compound according to any one of the formulae above.

Thus, in a further aspect, the present invention provides a release device comprising a behaviour-modifying compound according to any one of the formulae above. Preferably the release device is a lure.

The release device may be provided in an enclosure or envelope to prevent release of the behaviour-modifying until the release device is to be used, at which point the enclosure or envelope is removed. For example, the release device may be provided in an enclosure made from aluminium foil wrapped around the release device. Thus, in a related aspect, the present invention provides a release device comprising a behaviour-modifying compound according to any one of the formulae above, the release device being provided in an enclosure or envelope. A single release device may be provided in each enclosure or envelope, or multiple release devices may be provided in each enclosure or envelope. Multiple enclosures or envelopes containing the release device may be packaged together into a pack. Therefore, in a related aspect, the present invention provides a pack containing a plurality of release devices, each release device or group of release device being provided in an enclosure or envelope. For example, the pack may contain 2 (or more) release devices, 5 (or more) release devices, 10 (or more) release devices, 20 (or more) release devices or 25 (or more) release devices.

In a further aspect, the present invention provides a thrips killing device comprising a behaviour-modifying compound according to any one of the formulae above. Preferably the thrips killing device comprises a release device, preferably a lure.

In a related aspect, the present invention provides a sticky trap comprising a behaviour- modifying compound according to any one of the formulae above.

In a further related aspect, the present invention provides a thrips killing device comprising a behaviour-modifying compound according to any one of the formulae above, the thrips killing device being provided in an enclosure or envelope.

In another related aspect, the present invention provides a pack containing a plurality of thrips killing devices, each thrips killing device being provided in an enclosure or envelope. For example, the pack may contain 2 thrips killing devices, 5 thrips killing devices, 10 thrips killing devices, 20 thrips killing devices or 25 thrips killing devices.

In a further aspect, the present invention provides a thrips monitoring device comprising a behaviour-modifying compound according to any one of the formulae above. Preferably the thrips monitoring device comprises a release device, preferably a lure.

In a related aspect, the present invention provides a thrips monitoring device comprising a behaviour-modifying compound according to any one of the formulae above, the thrips monitoring device being provided in an enclosure or envelope.

In a further related aspect, the present invention provides a pack containing a plurality of thrips monitoring devices, each thrips monitoring device being provided in an enclosure or envelope. For example, the pack may contain 2 thrips monitoring devices, 5 thrips monitoring devices, 10 thrips monitoring devices, 20 thrips monitoring devices or 25 thrips monitoring devices.

In a related aspect, the present invention provides a method of attaching a release device comprising a behaviour-modifying compound according to any one of the formulae above to a thrips killing device or a thrips monitoring device.

In a related aspect, the present invention provides a method of making a release device comprising a behaviour-modifying compound according to any one of the formulae above, wherein the method includes the step of applying the compound to the release device. Suitably the behaviour-modifying compound is applied to the release device as a composition including a solvent, such as hexane, pentane or ether, to assist impregnation. However, the behaviour-modifying compound can also be applied undiluted.

Suitably the method includes the step of providing an enclosure or envelope for the release device to prevent release of the behaviour-modifying compound. In a related aspect, the present invention provides a method of releasing a behaviour- modifying compound according to any one of the formulae above in a glasshouse or polytunnel using a release device.

In a related aspect, the present invention provides a method of releasing a behaviour- modifying compound according to any one of the formulae above in an open field using a release device. In a related aspect, the present invention provides a method of treating a crop for thrips infestation, wherein the method includes the step of providing at least one thrips killing device and a behaviour-modifying compound according to any one of the formulae above associated with the thrips killing device. In a further related aspect, the present invention provides a method of treating a crop for thrips infestation, wherein the method includes the step of providing at least one pesticide or biological control agent and a behaviour-modifying compound according to any one of the formulae above associated with the pesticide or biological control agent.

In a further aspect, the present invention provides a method of monitoring thrips, wherein the method includes the step of providing at least one thrips monitoring device in association with a behaviour-modifying compound according to any one of the formulae above.

In a further aspect, the present invention provides a behaviour-modifying compound according to Formula (1), including the preferred compounds of Formula (1) listed above.

In a related aspect, the present invention provides a behaviour-modifying compound according to Formula (1), including the preferred compounds of Formula (1) listed above, for use in a method of monitoring or controlling thrips. Preferably, the compound is used in a method of monitoring or controlling Thripinae, such as T. palmi or F. intonsa. Most preferably the compound is for use in a method of monitoring or controlling T. palmi.

Any one or more of the aspects of the present invention may be combined with any one or more of the other aspects of the present invention. Similarly, any one or more of the features and optional features of any of the aspects may be applied to any one of the other aspects. Thus, the discussion herein of optional and preferred features may apply to some or all of the aspects. In particular, optional and preferred features relating to the nature of the behaviour-modifying compound, thrips species, crop, and behaviour-modifying compound concentrations apply to all of the aspects. Furthermore, optional and preferred features associated with a method or use may also apply to a product, in particular a composition or device, and vice versa.

The following numbered paragraphs contain statements of broad combinations of the inventive technical features herein disclosed: 1. A method of monitoring or controlling Thysanoptera (hereafter thrips) using a behaviour-modifying compound of Formula (1), wherein Formula (1) is:

where R is a C₂-C₈ straight or branched alkenyl group and the * denotes a stereocentre.

2. A method according to paragraph 1 , wherein R is a branched alkenyl group.

3. A method according to paragraph 1 or 2, wherein R is a C₃-C₅ alkenyl group. 4. A method according to any one of the preceding paragraphs, wherein R is a C₄ alkenyl group.

5. A method according to any one of paragraphs 1 to 4, wherein the stereocentre in Formula (1) has an R configuration.

6. A method according to any one of paragraphs 1 to 4, wherein the stereocentre in Formula (1) has an S configuration.

7. A method according to paragraph 4, wherein the compound is a compound of Formula (2):

A method according to paragraph 7, wherein the compound is a compound of

9. A method according to any one of the preceding paragraphs, wherein the method is used to monitor or control Thripinae.

10. A method according to paragraph 9, wherein the method is used to monitor or control Thrips palmi (Karny). 11. A method according to paragraph 9 or 10, wherein the method is used to monitor or control Frankliniella intonsa (Trybom).

12. A method according to any one of paragraphs 1 to 11 , wherein the compound is used as an attractant.

13. A method according to any one of paragraphs 1 to 11 , wherein the compound is used as a confusant.

14. A method according to any one of the preceding paragraphs, wherein the method includes killing thrips.

15. A method according to any one of the preceding paragraphs, wherein the compound is provided in a release device. 16. A method according to paragraph 15, wherein the release device comprises a matrix and the compound is dispersed within the matrix.

17. A method according to paragraph 16 wherein the matrix is made of rubber.

18. A method according to paragraph 15, wherein the release device is a container having walls that are permeable to the compound. 19. A method according to paragraph 18, wherein the walls are flexible.

20. A method according to paragraph 19, wherein the container is a bag or sachet. 21. A method according to any one of paragraphs 15 to 20, wherein the release device is a lure.

22. A method according to paragraph 15, wherein the release device is a sprayer.

23. A method according to paragraph 22, wherein the release device is an aerosol sprayer.

24. A method according to any one of paragraphs 15 to 23, wherein the release device is adapted to release the compound in an amount which is at least the same as the amount of the compound produced by a single thrips.

25. A method according to paragraph 24, wherein the release device is adapted to release the compound in an amount which is at least four times the amount of the compound produced by a single thrips.

26. A method according to any one of paragraphs 15 to 25, wherein the release rate from the release device is 1 to 1 ^χ 10⁶ picograms per hour.

27. A method according to paragraph 26, wherein the release rate from the release device is 1000 to 5 ^χ 10⁵ picograms per hour.

28. A method according to any one of paragraphs 15 to 27, wherein the release device is associated with a thrips killing device or a thrips monitoring device.

29. A method according to paragraph 28, wherein the release device is attached to the thrips killing device or a thrips monitoring device. 30. A method according to paragraph 28 or 29, wherein the thrips killing device or thrips monitoring device is a trap.

31. A method according to paragraph 30, wherein the trap comprises a substrate and a sticky adhesive coating applied to the substrate.

32. A method according to paragraph 31 , wherein the substrate is in the form of a sheet. 33. A method according to paragraph 30, wherein the trap comprises a container which in use is filled with a mixture of water and detergent.

34. A method according to paragraph 33, wherein the trap is a water trap. 35. A method according to paragraph 33 or 34, wherein the release device is suspended above the container.

36. A method according to any one of paragraphs 33 to 35, wherein the release device is attached to the container. 37. A method according to paragraph 30, wherein the release device is integral with the thrips killing device or thrips monitoring device.

38. A method according to paragraph 37, wherein the thrips killing device is a trap comprising a substrate and a sticky adhesive coating applied to the substrate, and the substrate or sticky adhesive coating is impregnated with the behaviour-modifying compound. 39. A method according to any one of the preceding paragraphs, comprising the step of providing a pesticide associated with the behaviour-modifying compound.

40. A method according to paragraph 39, wherein the pesticide comprises an insecticide selected from spinosad, azadirachtin, imidacloprid, thiacloprid, bifenthrin, cyfluthrin , d- phenothrin, fenpropathrin, fluvalinate, permethrin, resmethrin, pyrethrum, fenvalerate, lambda-cyhalothrin, acephate, naled, sulfotepp, chlorpyrifos, diazinon, methiocarb, endosulfan, kinoprene, fenoxycarb, pyriproxyfen, oxythroquinox, abamectin, pymetrozine and pyridaben.

41. A method according to paragraph 39 or 40, wherein the pesticide comprises a biopesticide. 42. A method according to any one of the preceding paragraphs, comprising the step of providing a biological control agent associated with the behaviour-modifying compound.

43. A method according to paragraph 42, wherein the biological control agent is a predatory bug or mite.

44. A method according to paragraph 39, wherein the behaviour-modifying compound is provided in a composition comprising the pesticide.

45. A method according to paragraph 44, wherein the pesticide comprises an insecticide selected from spinosad, azadirachtin, imidacloprid, thiacloprid, bifenthrin, cyfluthrin , d- phenothrin, fenpropathrin, fluvalinate, permethrin, resmethrin, pyrethrum, fenvalerate, lambda-cyhalothrin, acephate, naled, sulfotepp, chlorpyrifos, diazinon, methiocarb, endosulfan, kinoprene, fenoxycarb, pyriproxyfen, oxythroquinox, abamectin, pymetrozine and pyridaben.

46. A method according to paragraph 44 or 45, wherein the pesticide comprises a biopesticide. 47. A method according to any one of paragraphs 44 to 46, wherein the behaviour- modifying compound is present at a concentration of < 1 wt% based on the total weight of the composition.

48. A method according to paragraph 47, wherein the behaviour-modifying compound is present at a concentration of < 0.1 wt% based on the total weight of the composition. 49. A method according to paragraph 48, wherein the behaviour-modifying compound is present at a concentration of < 0.01 wt% based on the total weight of the composition.

50. A method according to any one of the preceding paragraphs, wherein the method of monitoring or controlling thrips includes attracting thrips in a crop growing area.

51. A method according to paragraph 50, wherein the crop comprises one or more of aubergine, avocado, bean, Benincasa hispida, cabbage, cantaloupe, Capsicum annum, carnation, chilli, Chinese cabbage, chrysanthemum, citrus, cotton, cowpea, cucumber, Cucurbita spp., Cyclamen, Ficus, hibiscus, lettuce, mango, melon, okra, onion, Orchidaceae, pea, peach, sweet pepper, plum, potato, pumpkin, rice, roses sesame, soyabean, squash, sunflowers, tobacco, or watermelon. 52. A method according to paragraph 50 or 51 , wherein the crop growing area is an enclosed crop growing area.

53. A method according to paragraph 52, wherein the crop growing area is enclosed by a glasshouse or polytunnel.

54. A method according to paragraph 50 or 51 , wherein the crop growing area is an open-field.

55. A method according to any one of paragraphs 1 to 49, wherein the method of monitoring or controlling thrips includes attracting thrips associated with a crop after the crop has been harvested. 56. A method according to any one of the preceding paragraphs, wherein the behaviour- modifying compound is present as part of a mixture of behaviour-modifying compounds.

57. A method according to paragraph 56, wherein the mixture is for modifying the behaviour of thrips and another pest or predator. 58. A composition for monitoring or controlling thrips, wherein the composition comprises a pesticide and a behaviour-modifying compound of Formula (1), wherein Formula (1) is:

where R is a C₂-C₈ straight or branched alkenyl group and the * denotes a stereocentre.

59. A composition according to paragraph 58, wherein R is a branched alkenyl group.

60. A composition according to paragraph 58 or 59, wherein R is a C₃-C₅ alkenyl group. 61. A composition according to any one of paragraphs 58 to 60, wherein R is a C₄ alkenyl group.

62. A composition according to any one of paragraphs 58 to 61 , wherein the stereocentre in Formula (1) has an R configuration.

63. A composition according to any one of paragraphs 58 to 61 , wherein the stereocentre in Formula (1) has an S configuration.

64. A composition according to paragraph 62, wherein the compound is a compound of Formula (2):

65. A composition according to paragraph 64, wherein the compound is a compound of Formula (3)

66. A composition according to any one of paragraphs 58 to 65, wherein the behaviour- modifying compound is present at a concentration of < 1 wt% based on the total weight of the composition.

67. A composition according to paragraph 66, wherein the behaviour-modifying compound is present at a concentration of < 0.1 wt% based on the total weight of the composition.

68. A composition according to paragraph 67, wherein the behaviour-modifying compound is present at a concentration of < 0.01 wt% based on the total weight of the composition.

69. A composition according to any one of paragraphs 58 to 68, wherein the pesticide comprises an insecticide selected from spinosad, azadirachtin, imidacloprid, thiacloprid, bifenthrin, cyfluthrin , d-phenothrin, fenpropathrin, fluvalinate, permethrin, resmethrin, pyrethrum, fenvalerate, lambda-cyhalothrin, acephate, naled, sulfotepp, chlorpyrifos, diazinon, methiocarb, endosulfan, kinoprene, fenoxycarb, pyriproxyfen, oxythroquinox, abamectin, pymetrozine and pyridaben.

70. A composition according to any one of paragraphs 58 to 69, wherein the pesticide comprises a biopesticide. 71. A method of treating a crop, the method comprising the step of applying a composition according to any one of paragraphs 58 to 70 to the crop.

72. A release device comprising the behaviour-modifying compound as defined in any one of paragraphs 1 to 8, for releasing the compound in the method of any one of paragraphs 1 to 57, wherein the release device is as defined in any one of paragraphs 15 to 49.

73. A release device according to paragraph 72, wherein the device is provided in an enclosure to prevent release of the behaviour-modifying compound.

74. A method of attaching a release device comprising a behaviour-modifying compound as defined in any one of paragraphs 1 to 8 to a thrips killing device or a thrips monitoring device.

75. A method of making a release device according to paragraph 72, wherein the method includes the step of applying a composition containing a behaviour-modifying compound as defined in any one of paragraphs 1 to 8 to the release device. 76. A method according to paragraph 75, wherein the composition applied to the release device comprises a solvent.

77. A method according to paragraph 75 or 76, wherein the method includes the step of providing an enclosure for the release device to prevent release of the behaviour-modifying compound. 78. A method of releasing a behaviour-modifying compound as defined in any one of paragraphs 1 to 8 in a glasshouse or polytunnel using a release device according to paragraph 72.

79. A method of treating a crop for thrips infestation, wherein the method includes the step of providing at least one thrips killing device comprising a compound as defined in any one of paragraphs 1 to 8 associated with the thrips killing device.

80. A method of monitoring thrips, wherein the method includes the step of providing at least one thrips monitoring device comprising a compound as defined in any one of paragraphs 1 to 8 associated with the thrips monitoring device.

81 A compound according of Formula (2):

A compound according to paragraph 81 , wherein the compound is a compound of

83. A compound according to paragraph 81 or 82, wherein the compound is for use in a method of monitoring or controlling thrips. 84. A compound according to paragraphs 83, wherein the compound is for use in a method of monitoring or controlling Thripinae.

85. A compound according to paragraph 84, wherein the compound is for use in a method of monitoring or controlling Thrips palmi (Karny).

86. A compound according to paragraph 83 or 84, wherein the compound is for use in a method of monitoring or controlling Frankliniella intonsa (Trybom).

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be described in greater detail. In particular, the considerable efforts that have been made to identify pheromones of T. palmi, to create synthetic versions of such pheromones, and to establish the behaviour-modifying properties of those pheromones. Collection of T. palmi

Adult male and female T. palmi used for the collection of volatile chemicals were obtained from the leaves of commercial eggplant crops (Solanum melongena L.) being grown in a polytunnel at Kobori near Utsunomiya, Tochigi Prefecture, Japan (N 36^° 30.483' E 139 59.536').

For initial volatile collection experiments adult male and female T. palmi were transported from Utsunomiya University, Japan, in small plastic boxes (ca. 12 cm x 8 cm x 4 cm) lined with layers of moistened tissue on fresh sprouting beans to Food and Environment Research Agency, Central Science Laboratory (CSL), York. The insects were held in secure quarantine facilities at (23°C, 65% relative humidity, 16:8 light:dark) until required for use in experiments under CSL (now Fera) licence PHSI 23/6735.

Additional collections of adult male and female T. pa/m/^'were made in the field in Japan in August 201 1 and again in October 201 1 at Kobori. Collections were made between 10 am and 4 pm. Adults were aspirated off the eggplant leaves and held in clean glass containers (50 ml round bottomed flasks) and kept cool in an ice box. Approximately 1 gram of eggplant leaves and petals were added to the round bottomed flasks to provide a food source and maintain humidity levels until the thrips were used for experimentation. Four separate collections were made with the first containing approximately 35 males and 400 females, the second 20 males and 365 females the third 26 males and 415 females and the fourth 18 males and 300 females. Females were distinguishable from males due to their larger size, and the presence of an ovipositor at the end of their abdomen.

To confirm that the collected thrips were T. palmi, representative samples were checked under a dissecting microscope in the UK and Japan.

Headspace volatile collection:

All glassware used in the collection of headspace volatiles was cleaned by first washing in a 5 - 10% detergent solution, then rinsing with distilled water, drying with acetone and finally heating at 200°C in a clean oven overnight to remove potential contaminants. Teflon tubing used in the portable entrainment apparatus described below was cleaned by first washing in a 5 -10% detergent solution, rinsing with distilled water, drying with acetone and then leaving in a fume hood at room temperature overnight to allow solvent to fully evaporate.

Two alternative methods were used to collect volatile compounds emitted by T. palmi. The first of these methods was carried out on T. palmi samples transferred to FERA in York, and the second was carried out on T. palmi samples in Utsunomiya, Japan.

Entrainments in FERA CSL Adult T. palmi were removed from the sprouting beans with a small aspirator, anaesthetized with carbon dioxide, and transferred into a clean glass container (volume 1.9 ml) that was then sealed with Teflon tape. The thrips were illuminated from above with a 60 W tungsten filament lamp to induce patrolling behaviour (Kirk and Hamilton, 2004). Head space volatiles were collected on a divinylbenzene (DVB)/carboxen/polydimethylsiloxane (PDMS) solid phase microextraction (SPME) fibre assembly (57348-U, Supelco, Poole, UK) at 27°C for up to 18 hr (Kirk and Hamilton, 2004). The numbers of males and females entrained in this way varied from 30 to 100 per replicate and in total approximately 4 entrainments of each sex were carried out in this way. After each entrainment the SPME fibre was sealed in a clean glass tube and transferred to Keele University for GC/MS analysis.

Entrainments in Utsunomiva

After field collection the 50 ml round bottomed flasks containing the thrips were transferred to the laboratory and the headspace volatiles collected using a set of portable entrainment apparatus (Barry Pye, Kings Walden, Herts. UK). Air drawn into the entrainment apparatus was first cleaned by passing it through an activated charcoal filter and then divided via a

Swagelok T-connector into 2 separate lines. This air then entered the round bottomed flasks containing the thrips and plant material via a Drechsel head. The air exiting from each round bottomed flask then passed into a glass column containing an adsorbent polymer (ORBO 402, Tenax TA). All tubing and components within the entrainment apparatus were connected with Swagelok connectors or Teflon tubing joints and were sealed with Teflon tape (Sigma-Aldrich Company Ltd., Gillingham, United Kingdom) to eliminate leakage of air. Air flow at the outlet of the Tenax tube was measured with a bubble flow meter and maintained at 5 ml s^" by adjustment of a rotameter (GPE Ltd., Leighton Buzzard, United Kingdom) at the air inlet side of the apparatus.

The two entrainment lines were run in parallel continuously for a period of 4 days. The Tenax TA columns were replaced every 24 hours with a fresh adsorbent column when fresh petals were also added to both round bottomed flasks.

Volatiles were eluted from the Tenax tubes using 2 ml of an 95:05 mixture of n-hexane and ethyl acetate. All four extracts were concentrated under a gentle stream of air to 1 ml and returned to Keele University where they were combined and volume reduced again to 100 μΙ for GC/MS analysis. The amount of monoterpene ester present in the T. palmi extracts were quantified by comparison of the peak area of the unknown ester with a known amount of neryl (S)-2-methylbutanoate of known concentration by GC/MS analysis. Chemical analysis of T. palmi volatile compounds

GC/MS

Coupled gas chromatography-mass spectrometry analyses were carried out on either a HP 5890 11+ gas chromatograph (GC) coupled to HP 5972A mass spectrometer or an Agilent 7890 GC coupled to an Agilent 5973 mass spectrometer (Agilent Technologies, Ipswich, UK). Both instruments were operated in electron impact (El) (70 eV, 180°C) mode.

SPME-collected headspace volatiles obtained at FERA CSL and hexane:ethyl acetate extracts of Tenax entrainment tubes obtained in Utsonomiya were analyzed on both HP5MS and DBWax columns (30 m x 0.25 mm inner diameter 0.25-μηι phase thickness) carrier gas was helium at 1 ml min^" .

SPME samples from male T. palmi were analysed separately to those from female T. palmi. Analysis of SPME fibres was carried out by introducing the fibres into the HP 5890 GC via a Merlin Microseal (Thames-Restek, High-Wycombe, UK) septum-less heated injector (180°C) fitted with a SPME glass injection sleeve (0.75 mm i.d.; Supelco, UK). SPME samples were desorbed for 8 minutes before the fibre assembly was withdrawn. An initial oven

temperature of 40°C was held for 2 minutes then the temperature was increased (10°C min^" ) to 250°C (10 minutes).

For the Tenax entrainment tube extracts the samples were introduced via a heated injector port (180°C). The GC was temperature programmed with an initial 2 minutes at 40°C, an increase of 10°C min^"1 to 120°C, an increase of 6°C min^"1 to 180°C, then an increase of 10°C min^"1 to a final temperature of 250°C, held for 1 minute.

The gas chromatogram of volatile compounds obtained from male T. palmi at FERA CSL showed a compound that eluted at around 18 minutes, which was completely absent from chromatograms for the females. The mass spectrum of the peak suggested a monoterpene ester structure similar to that of the western flower thrips aggregation pheromone neryl (S)-2- methylbutanoate but with a relative molecular weight (RM) of 236.

Comparison with synthetic molecules

The small amounts of volatile compounds produced by T. palmi mean that such compounds can only be collected in extremely small amounts. This presents a considerable challenge when it comes to characterising the emitted compounds because the sensitivity of most characterisation techniques, including N.M.R., is too low. To solve this considerable problem, the present inventors devised an alternative approach to identify the male-specific compound with a RM of 236.

Specifically, to identify the compound of interest, a library of monoterpene C5 esters i.e. pentanoates, pentenoates and pentynoates was created. The library contains 89

compounds which have a RM of 236 and spectra and relative retention time of these compounds were compared to the T. palmi RM 236 compound. To create this library, the following general reaction was carried out.

A monoterpene alcohol (1 mmol), a 5-carbon carboxylic acid (1.2 mmol), and 4- dimethylaminopyridine (DMAP) (0.05 mmol) were dissolved in dry dichloromethane (2 ml), and the solution was stirred in an ice bath. Λ/,Λ/'-dicylcohexylcarbodiimide (DCC) (1.2 mmol) was added portion-wise over 30 minutes, and stirring was continued for another 30 minutes with cooling and then for 3 hours at room temperature. Then the by-product in the reaction, dicyclohexylurea, was filtered off, and the precipitate was washed with petroleum spirit (boiling point 40-60°C). The filtrate was washed with saturated aqueous sodium bicarbonate solution, dilute hydrochloric acid, and water, dried over magnesium sulfate, and filtered. After concentration, the residue was purified by column chromatography on silica gel (100-200 mesh), and eluted with a 98:2 petroleum spirit to ethyl acetate mixture. Pure fractions identified by thin layer chromatography were collected and concentrated (pure ester, yield -95%).

In some instances the 5-carbon carboxylic acid was synthesised from the corresponding 5- carbon alcohol. In such instances, Jones reagent was added portion-wise over a 30 minute period to a stirred solution of the alcohol in acetone (2 ml/mmol) at 0°C until an orange colour persisted. The reaction mixture was then stirred for one hour. The progress of the reaction was monitored by TLC analysis. Once the reaction was complete, excess reagent was quenched by the addition of ethanol or methanol and then stirred for one hour. The solution was then concentrated under vacuum. The residue was taken up in ethyl acetate, washed with water, saturated brine, dried over anhydrous MgS0₄, filtered and concentrated to afford the crude carboxylic acid (yield 75-80%).

GC/MS analysis was carried out for each of the monoterpene esters using HP5MS and DBWax columns, as described above. Kovats retention index (Kl) data obtained for certain of the molecules by GC/MS analysis is presented in Table 1. The results in Table 1 show that the monoterpene ester lavandulyl 3-methyl-3-butenoate (RM 236) has an identical Kovats retention index to the male specific compound of interest. Furthermore, the inventors found that lavandulyl 3-methyl-3-butenoate enhanced the signal from the male specific compound when included in the T. palmi samples for GC/MS analysis.

TABLE 1

After determining that the compound having a RM of 236 corresponded to lavandulyl 3- methyl-3-butenoate, the inventors next wished to determine whether the molecule emitted by the T. palmi had a specific stereochemistry about the stereocentre in the lavandulyl group. To do this, (R) and (S) enantiomers of lavandulyl 3-methyl-3-butenoate were made and compared to the samples obtained from T. palmi using chiral GC/MS chromatography, as described below.

Synthesis of enantiomeric lavandulol from racemic lavandulol

Enantiomers of lavandulol were resolved using lipase-catalysed transesterification. A mixture of (i)-lavandulol (2.31 g, 15 mmol), succinic anhydride (3 g, 30 mmol) and lipase (1.115 g, Fluka, 1777 U/mmol of (i)-lavandulol) was stirred in 50 ml ether at room temperature. Stirring was stopped periodically and aliquots of the supernatant solution analyzed by GC on a Cyclosil-B column (30 m x 0.25 mm; 0.25 μηι film) in order to monitor the progress of the transesterification. The reaction was terminated after 48 hours by filtration of the enzyme and dilution with 20 ml ether. The ethereal mixture was stirred with 1 M Na₂C0₃ solution (60 ml) for 30 minutes. The basic aqueous layer was extracted with additional 20 ml of ether. The combined organic fractions were extracted with more 1 M Na₂C0₃ solution (20 ml), dried over MgS0₄ and the solvent removed to give 0.68 g of the (/^-enantiomer with an enantiomeric excess of 98% and chemical purity of 90%.

The combined basic aqueous fractions were hydrolyzed by stirring with 1 M NaOH solution (50 ml) for 5 hours and then the product was extracted with ether (60 ml), dried over MgS0₄ and the solvent removed to give 0.80 g of the (S)-enantiomer with an enantiomeric excess of 54% and chemical purity of 99%.

The lavandulol was subsequently used to produce (/^-lavandulyl 3-methyl-3-butenoate and (S)-lavandulyl 3-methyl-3-butenoate (purity 100% by TLC) in the reaction scheme described above using 3-methyl-3-butenoic acid as the 5-carbon acid.

Chiral GC/MS

Analysis of the enantiomeric composition of lavandulyl 3-methyl-3-butenoate standard and authentic thrips material was carried out by GC/MS on a Cyclosil-B column (30 m x 0.25 mm; 0.25 μηι film). The carrier gas was helium (flow rate 1 ml min^" ). Samples were introduced via a heated injector port (180°C) and the GC was temperature programmed with an initial 2 minutes at 55°C, an increase of 5°C min^"1 to 115°C, held for 1 minute, then an increase of 0.5°C min^"1 to 165°C. Results from the chiral chromatography showed that (/^-lavandulyl 3-methyl-3-butenoate and (S)-lavandulyl 3-methyl-3-butenoate are clearly separated with retention times of 45.195 minutes and 45.345 minutes respectively. The male specific T. palmi compound eluted at 45.198 minutes which suggested that the T. palmi compound was (/^-lavandulyl 3-methyl-3- butenoate. Co-injection of the T. palmi compound with the (/^-lavandulyl 3-methyl-3- butenoate standard gave peak enhancement, providing further support that the T. palmi compound is (/^-lavandulyl 3-methyl-3-butenoate.

Field Trials The effect of (/^-lavandulyl 3-methyl-3-butenoate was tested by comparing the number of thrips caught on traps with and without the synthetic pheromone. Rectangular blue sticky traps, 10 cm x 25 cm (Takitraps®, Syngenta Bioline, UK), were placed in a greenhouse crop of eggplants (Solanum melongena variety 'Senryo 2') near Utsunomiya, Japan (N +36° 30.483' E +139° 59.536'). The greenhouse was a plastic tunnel about 50 m long and 5 m wide with two rows of crop running along it. Traps were suspended with the base about 10 cm above the canopy of the crop, which was at a height of about 1.2 metres. The crop was predominantly infested with two species of thrips: Thrips palmi (Karny) and, to a lesser extent, Frankliniella intonsa (Trybom). The north-facing side of each trap was exposed and a cleaned rubber septum (diameter 6.3 mm, length 10.8 mm, International Pheromone Systems Ltd., UK) was stuck to the middle of the exposed side. The treatment septa received 30 μg of (/^-lavandulyl 3-methyl-3-butenoate in 30 μΙ hexane and the control septa received 30 μΙ hexane.

Pairs of treatment and control traps (treatment traps with treatment septa and control traps with control septa) with the order randomised within each pair were set out along the length of the tunnel. A series of four experiments was conducted over 8 days with the spacing between traps within each pair set at either 1.6 m or 4 m and the duration of the experiment lasting either 1 day or 4 days. New traps were set out and re-randomised for each of the four experiments. The results of the four experiments were combined. The data were log ₀ (x+1) transformed and analysed by analysis of variance with trap pairs treated as blocks.

Treatment traps caught more than control traps in all four experiments for both female and male Thrips palmi and the effect was statistically significant (Fi_,24 = 13.05, P <0.001). The results were also statistically significant for females (Fi_,24 = 12.22, P =0.002) and males (Fi_,24 = 6.71 , P =0.016) when analysed separately. The treatment traps also caught a greater number of Frankliniella intonsa than control traps, and the effect was statistically significantly (Fi_,24 = 4.55, P =0.043).

TABLE 2

These data demonstrate that (/^-lavandulyl 3-methyl-3-butenoate is effective at attracting thrips, in particular Thripinae such as T palmi and F. intonsa. The work leading to this invention has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 252258.

REFERENCES

Br0dsgaard, H. F. (1989) "Coloured sticky traps for Frankliniella occidentalis (Pergande) (Thsanoptera, Thripidae) in glasshouses" Journal of Applied Entomology, 107(2), 136-140. Cannon, R.J.C., Matthews, L. & Collins, D.W. (2007a) "A review of the pest status and control options for Thrips palmi' Crop Protection 26, 1089-1098.

Cannon, R.J.C., Matthews, L, Collins, D.W., Agallou, E., Bartlett, P.W., Walters, K.F.A., Macleod, A., Slawson, D.D. & Gaunt, A. (2007b) "Eradication of an invasive alien pest, Thrips palmi' Crop Protection 26, 1303-1314. Kawai, A. (2001) "Population management of Thrips palmi Karny" [In Japanese with English summary] Japanese Journal of Applied Entomology and Zoology Ab, 39-59.

Kirk, W.D.J, and Hamilton, J.G.C. (2004) "Evidence for a male-produced sex pheromone in the western flower thrips Frankliniella occidentalis" Journal of Chemical Ecology, vol. 30(1), 167-174. Nagai, K. (1993) "Studies on integrated pest management of Thrips palmi Karny" [In Japanese with English summary]. Spec Bull Okayama Agric Exp Stn 82, 1-55.

Yano, E. (2004) "Recent development of biological control and IPM in greenhouses in Japan" Journal of Asia-Pacific Entomology 7, 5-1 1.

Claims

1. A method of monitoring or controlling Thysanoptera (hereafter thrips) using a behaviour-modifying compound of Formula (1), wherein Formula (1) is:

where R is a C₂-C₈ straight or branched alkenyl group and the * denotes a stereocentre.

2. A method according to claim 1 , wherein R is a branched alkenyl group.

3. A method according to claim 1 or 2, wherein R is a C₃-C₅ alkenyl group.

4. A method according to any one of claims 1 to 3 wherein the compound is a compound of Formula (2):

5. A method according to any one of the previous claims, wherein the method is used to monitor or control Thrips palmi (Karny) or Frankliniella intonsa (Trybom).

6. A method according to any one of the previous claims, wherein the compound is used as an attractant or a confusant.

7. A method according to any one of the preceding claims, wherein the method includes killing thrips.

8. A method according to any one of the preceding claims, wherein the compound is provided in a release device.

9. A method according to claim 8, wherein the release device (a) comprises a matrix and the compound is dispersed within the matrix, suitably wherein the matrix is made of rubber;

(b) is a container having walls that are permeable to the compound, suitably wherein the walls are flexible, suitably wherein the container is a bag or sachet; (c) is a lure; or

(d) is a sprayer, suitably an aerosol sprayer.

10. A method according to claim 8 or 9, wherein the release device is adapted to release the compound in an amount which is

(a) at least the same as the amount of the compound produced by a single thrips; (b) at least four times the amount of the compound produced by a single thrips;

(c) a release rate from the release device of 1 to 1 ^χ 10⁶ picograms per hour; or

(d) a release rate from the release device of 1000 to 5 ^χ 10⁵ picograms per hour.

11. A method according to any one of claims 8 to 10, wherein the release device is associated with a thrips killing device or a thrips monitoring device, suitably wherein the release device is attached to the thrips killing device or a thrips monitoring device or wherein the release device is integral with the thrips killing device or thrips monitoring device.

12. A method according to claim 11 , wherein the thrips killing device is a trap comprising a substrate and a sticky adhesive coating applied to the substrate, and the substrate or sticky adhesive coating is impregnated with the behaviour-modifying compound.

13. A method according to any one of the preceding claims, comprising the step of providing a pesticide associated with the behaviour-modifying compound, suitably wherein the pesticide comprises an insecticide selected from spinosad, azadirachtin, imidacloprid, thiacloprid, bifenthrin, cyfluthrin , d-phenothrin, fenpropathrin, fluvalinate, permethrin, resmethrin, pyrethrum, fenvalerate, lambda-cyhalothrin, acephate, naled, sulfotepp, chlorpyrifos, diazinon, methiocarb, endosulfan, kinoprene, fenoxycarb, pyriproxyfen, oxythroquinox, abamectin, pymetrozine and pyridaben.

14. A method according to any one of the preceding claims, wherein the method of monitoring or controlling thrips includes attracting thrips in a crop growing area, suitably wherein the crop comprises one or more of aubergine, avocado, bean, Benincasa hispida, cabbage, cantaloupe, Capsicum annum, carnation, chilli, Chinese cabbage, chrysanthemum, citrus, cotton, cowpea, cucumber, Cucurbita spp., Cyclamen, Ficus, hibiscus, lettuce, mango, melon, okra, onion, Orchidaceae, pea, peach, sweet pepper, plum, potato, pumpkin, rice, roses sesame, soyabean, squash, sunflowers, tobacco, or

watermelon.

15. A composition for monitoring or controlling thrips, wherein the composition comprises a pesticide and a behaviour-modifying compound of Formula (1), wherein Formula (1) is:

where R is a C₂-C₈ straight or branched alkenyl group and the * denotes a stereocentre.

16. A composition according to claim 15, wherein the compound is a compound of Formula (2):

17. A release device comprising the behaviour-modifying compound as defined in any one of claims 1 to 4, for releasing the compound in the method of any one of claims 1 to 16, wherein the release device is as defined in any one of claims 9 to 12.

18. A method of attaching a release device comprising a behaviour-modifying compound as defined in any one of claims 1 to 4 to a thrips killing device or a thrips monitoring device.

19. A method of treating a crop for thrips infestation, wherein the method includes the step of providing at least one thrips killing device comprising a compound as defined in any one of claims 1 to 4 associated with the thrips killing device.

20. A compound according to Formula (2)

A compound according to claim 20, wherein the compound is a compound of