AU1537400A - Termite attractant and/or feeding stimulant - Google Patents

Description

WO 00/36914 PCT/AU99/01033 1 TERMITE ATTRACTANT AND/OR FEEDING STIMULANT TECHNICAL FIELD The present invention is concerned with attractants 5 and/or feeding stimulants for termites and, more particularly, with attractants and/or feeding stimulants for use in termite baits and as a component of termiticidal compositions. 10 BACKGROUND ART Organochlorines have underpinned termite control around the world including in Australia, for many decades. With the ban on the use of organochlorines for termite control in Australia since 1995 and earlier or at similar 15 times in other countries, increasing efforts are being mounted to develop alternative termite management systems. Bait systems for the control of active termite infestations are considered increasingly the key management option for such situations. 20 In bait systems termites are offered a matrix on which the insects ought to feed in preference to other food sources available to a termite colony. Termites either take up a slow-acting, non-repellent lethal product which is incorporated into the food (matrix) or the termites 25 which aggregate in the matrix are directly treated with such a product. In both scenarios the agent is transported into the nest by the foragers and there distributed throughout the colony either via food exchange or mutual grooming between nest mates. 30 Following considerable research around the world there is now a growing awareness that just finding an effective bait toxin, initially thought to be the main impediment to the application of baits, is no guarantee at all that a WO00/36914 PCT/AU99/01033 2 bait system will work effectively in practice. Control strategies relying on baits have to cope with the fact that termites have a choice and that the insects cannot be forced to make contact with the baits. Termites have to be 5 able to locate a bait station in the first place, and once it is found, be attracted to it in significant numbers so that adequate transfer of the toxin from the bait site to the colony can occur. Differences in behaviour between species of termite, between colonies within a species and 10 between conditions at various sites potentially restrict the effectiveness of this control strategy. Currently used bait matrices, in most cases just straight cellulose products (timber, cardboard, paper), do not necessarily ensure contact and build up of termite numbers in bait 15 stations in a reliable, predictable fashion. Attempts have been made to enhance the attraction of termites to bait matrices through the addition of attractant compounds. For example, International Application WO99/07218 describes the use of 2,4 heptadienal 20 as an attractant for social pest insects such as wasps and termites. United States Patent No. 5,637,298 describes 2-4 naphthalenemethanol derivative substituted at the 7 or 8 position of the naphthalene ring structure by methyl, ethyl, propyl or isopropyl, and indicates that these 25 compounds increase bait acceptance by termites. Likewise, United States Patent No. 5,756,114 describes the incorporation of certain aromatic compounds including resorcylic acid, protecatechuic acid and vanillic acid into baits on the basis that they act as food odour attractants. 30 These compounds apparently mimic the trail-marking pheromone (Z,Z,E)-3,6,8-dodecatrien-1-ol. Thus, while they promote termite aggregation they do not necessarily stimulate feeding behaviour, and any increased feeding may WO00/36914 PCT/AU99/01033 3 be a consequence only of the increased numbers of termites at a selected site. Termites are social insects and the social organisation of termite colonies largely depends on 5 chemical signals present in the environment or produced by members of the colony. These signals modulate a variety of behaviours including foraging for food or communal exploitation of a food source. For example, during feeding, termites release a chemical signal from an 10 exocrine gland that stimulates nest mates to feed at the same site, thereby ensuring a rapid and efficient exploitation of the food source. All species of termite have paired labial glands located in the thorax. The glandular ducts join in the 15 head with those of the water sacs and the contents are secreted from the mouth as saliva. This secretion has been reported to have various functions depending on the species, and has variously been identified as a defensive substance in soldier termites, a regulator of nest 20 microclimate, a supporter of fungal cultivation in the nest or as a social nutrient. In addition, the labial glands have been said to secrete a cementing substance for nest construction or gallery building and have been identified as a source of digestive enzymes. 25 More recently, Reinhard et al., Journal of Chemical Ecology, Vol. 23 No. 10, 1997 concluded that the labial gland secretion may play a pheromonal role during food exploitation, and that this might be a general phenomenon in termites. Reinhard et al. took labial gland extracts 30 and used these in feeding choice tests. They observed that the labial gland secretion carries a signal that stimulates gnawing and feeding by termite workers during food exploitation. The extract of the labial gland even WO 00/36914 PCT/AU99/01033 4 elicited feeding behaviour when applied without food onto glass plates. These extracts were tested with both Reticulitermes santonensis and Schedorhinotermes lamanianus and proved to elicit a significant feeding preference in 5 the two species. In view of this, Reinhard et al. suggested that the signal function of the labial gland secretion for food exploitation is phylogenetically old and non-species specific. The chemical signal has now been identified for the first time and has proved to work as a 10 powerful feeding stimulant at natural low concentrations on a wide range of termite species. In view of this a class of compounds which stimulate termite feeding has been identified. 15 DISCLOSURE OF THE INVENTION According to a first aspect of the present invention there is provided a feeding stimulant for stimulating feeding activity in termites, comprising a compound having at least two OR groups, each of which is a substituent of 20 an aryl moiety, and R is hydrogen or an organic group, and addition compounds thereof. Where the feeding stimulant is a compound in which at least one R is an organic group it may have feeding stimulating activity or may be a pre-cursor of a compound 25 with feeding stimulating activity. In the former case, the organic group is preferably selected from the group consisting of alkyl, substituted alkyl, aryl or substituted aryl, and in the latter case is typically a compound which is hydrolysed to one having 30 feeding stimulating activity, such as those in which the organic group is a carbohydrate moiety. P-Arbutin is one such compound. Polymers or oligomers such as polyphenylethers, as well as being long-lived in the WO00/36914 PCT/AU99/01033 5 environment, will progressively hydrolyse to compounds having feeding stimulating activity. Compounds having feeding stimulating activity typically have an aromatic nucleus substituted by said at 5 least two OR groups. Typically such compounds have the following general formula I: OR

R

6 1 R 2 10 (7) RS

R

3

R

4 15 wherein R, is selected from the group consisting of hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, aralkyl, and substituted aralkyl;

R

2 , R 3 , R 4 , R 5 and R 6 are independently selected from the group consisting of hydrogen, hydroxyl, alkyl, 20 substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, aryloxy, substituted aryloxy, alkaryl, substituted alkaryl, alkaryloxy and substituted alkaryloxy, or R 2 and R 3 together, R 3 and R 4 together, R 4 and R 5 together and/or Rs and R 6 together form an aryl group; 25 provided only that at least one of R 2 , R 3 , R 4 , R5 or R 6 is hydroxyl, alkoxy, substituted alkoxy, aryloxy, substituted aryloxy, alkaryloxy or substituted alkaryloxy. Preferably, RI is selected from the group consisting of hydrogen, alkyl, aryl and alkaryl. 30 More preferably, RI is selected from the group consisting of hydrogen, methyl, ethyl, phenyl and benzyl. More preferably still, RI is hydrogen. Preferably, R 2 , R 3 , R 4 , Rs and R 6 are independently WO00/36914 PCT/AU99/01033 6 selected from the group consisting of hydrogen, hydroxyl, alkyl, alkoxy, aryl, aryloxy, alkaryl, and alkaryloxy. More preferably, R 2 , R 3 , R 4 , R 5 and R 6 are independently selected from the group consisting of 5 hydrogen, hydroxyl, methyl, ethyl, methoxy, ethoxy, phenyl, phenoxy, benzyl and benzyloxy. More preferably still, at least one of R 2 , R 3 , R 4 , Rs or R 6 is hydroxyl. In particular, R 2 or R 6 , R 3 or R 5 or R 4 is typically hydroxyl. 10 Particularly preferred compounds for use in the present invention are selected from the group consisting of: p-hydroquinone (1,4-dihydroxybenzene) catechol (1,2-dihydroxybenzene) 15 resorcinol (1,3-diahydroxybenzene) phloroglucinol (1,3,5-trihydroxybenzene) 4-methoxyphenol methoxyhydroquinone (l-methoxy-2,5-dihydroxybenzene) 1,4-dimethoxybenzene 20 4-phenoxyphenol phenylhydroquinone 4-benzyloxyphenol Moreover, addition compounds such as quinhydrone (an addition compound of 1 mole hydroquinone and 1 mole 25 quinone) are also envisaged. Alternatively, said compound may have a plurality of aryl moieties. Preferably each said aryl moiety is a benzene ring and the compound is a polyphenylether. Typically, the 30 polyphenylether is an ether of p-hydroquinone having between 2 and 5 p-hydroquinone residues. The composition may further comprise a biologically acceptable carrier and/or extender.

WO00/36914 PCT/AU99/01033 7 As used throughout the specification and claims the term "alkyl" refers to straight or branched chain alkyl radicals, preferably C 1 -Cl 0 alkyl radicals and, more preferably, CI-C 4 alkyl radicals. 5 As used throughout the specification and claims the term "substituted alkyl" refers to an alkyl radical substituted by any substituent, conveniently, by hydroxyl, alkoxy, carboxy, carboxyalkyl, carbamoyl, carbamido, amino, mono- or di- alkyl substituted amino, halogen, 10 alkylcarbonyloxy or alkylcarbonylamino. As used throughout the specification the term "aryl" refers to a six-membered carbocyclic aromatic ring or a five- or six-membered heterocyclic aromatic ring containing 1, 2 or 3 oxygen, nitrogen or sulphur atoms as the 15 heteroatom, and includes fused ring systems containing a plurality of such rings. As used throughout the specification and claims the term "substituted aryl" refers to an aryl radical substituted by any substituent, conveniently, by hydroxyl, 20 alkoxy, carboxy, carboxyalkyl, carbamoyl, carbamido, amino, mono- or di- alkyl substituted amino, halogen, alkylcarbonyloxy or alkylcarbonylamino. As used throughout the specification and claims the term "alkoxy" refers to an alkoxy radical containing a 25 straight or branched chain alkyl radicals, preferably Cl-Ci 0 alkyl radicals and, more preferably, CI-C 4 alkyl radicals. As used throughout the specification and claims the term "substituted alkoxy" refers to an alkoxy radical substituted by any substituent, conveniently, by hydroxyl, 30 alkoxy, carboxy, carboxyalkyl, carbamoyl, carbamido, amino, mono- or di- alkyl substituted amino, halogen, alkylcarbonyloxy or alkylcarbonylamino.

WO00/36914 PCT/AU99/01033 8 As used throughout the specification and claims the term "aryloxy" refers to an aryloxy radical containing a six-membered carbocyclic aromatic ring or a five- or six membered heterocyclic aromatic ring containing 1, 2 or 3 5 oxygen, nitrogen or sulphur atoms as the heteroatom, and includes fused ring systems containing a plurality of such rings. As used throughout the specification and claims the term "substituted aryloxy" refers to an aryloxy radical 10 substituted by any substituent, conveniently, by hydroxyl, alkoxy, carboxy, carboxyalkyl, carbamoyl, carbamido, amino, mono- or di- alkyl substituted amino, halogen, alkylcarbonyloxy or alkylcarbonylamino. As used throughout the specification and claims the 15 term "alkaryl" refers to an alkaryl radical comprising a straight or branched chain alkylene radical, preferably a

C

1

-C

1 o alkylene radical and, more preferably, a C 1

-C

4 alkylene radical and a six-membered carbocyclic aromatic ring or a five- or six-membered heterocyclic aromatic ring 20 containing 1, 2 or 3 oxygen, nitrogen or sulphur atoms as the heteroatom, and includes fused ring systems containing a plurality of such rings. As used throughout the specification and claims the term "substituted alkaryl" refers to an alkaryl radical 25 substituted by any substituent, conveniently, by hydroxyl, alkoxy, carboxy, carboxyalkyl, carbamoyl, carbamido, amino, mono- or di- alkyl substituted amino, halogen, alkylcarbonyloxy or alkylcarbonylamino. As used throughout the specification and claims the 30 term "alkaryloxy" refers to an alkaryloxy radical containing a straight or branched chain alkyleneoxy group, preferably a CI-C 0 alkyleneoxy group and, more preferably, ClC 4 alkyleneoxy group, and a six-membered carbocyclic WO00/36914 PCT/AU99/01033 9 aromatic ring or a five- or six-membered heterocyclic aromatic ring containing 1, 2 or 3 oxygen, nitrogen or sulphur atoms as the heteroatom, and includes fused ring systems containing a plurality of such rings. 5 As used throughout the specification and claims the term "substituted alkaryloxy" refers to an alkaryloxy radical substituted by any substituent, conveniently, by hydroxyl, alkoxy, carboxy, carboxyalkyl, carbamoyl, carbamido, amino, mono- or di- alkyl substituted amino, 10 halogen, alkylcarbonyloxy or alkylcarbonylamino. As used throughout the specification and claims, the words "comprise", "comprises" and "comprising" are used in a non-exclusive sense, except where the context requires otherwise. 15 According to a second aspect of the present invention there is provided a method of stimulating feeding activity in termites, comprising the steps of: (1) providing a feeding stimulant as described above; and 20 (2) applying said feeding stimulant to a locus. Preferably, there is a food source at said locus. According to a third aspect of the present invention there is provided a method of attracting termites to a locus, comprising the steps of: 25 (1) providing a food source at said locus, (2) providing a feeding stimulant as described above; and (3) applying said feeding stimulant to said locus. The compounds of general formula I act as a feeding 30 stimulant and/or attractant to termite species, in particular, to Mastotermes darwiniensis, Coptotermes acinaciformis, Kalotermes flavicollis, Cryptotermes brevis, Hodotermes mossambicus, Zootermopsis angusticollis, WO00/36914 PCT/AU99/01033 10 Reticulitermes flavipes, Reticulitermes santonensis, Heterotermes indicola, Schedorhinotermes lamanianus, Coptotermes formosanus, Nasutitermes nigriceps, Nasutitermes exitiosus, Trinervitermes trinervoides and 5 Macrotermes subbyalinus. According to a fourth aspect of the present invention there is provided a bait for attracting termites, comprising: (1) a food source; and 10 (2) a feeding stimulant as described above. Typically the food source is a source of cellulose such as paper, cardboard, canite, chipboard, and sound or fungally decayed wood. The compound of general formula I is applied to the bait matrix in any convenient manner, 15 such as by spraying a solution of the compound on the bait matrix, soaking the bait matrix in such a solution or by admixture with a solid compound of general formula I. The bait matrix may also contain synergists and other attractants, as well as beneficial components such as 20 nitrogen-containing compounds, carbohydrates and the like as nutrients. Where necessary, antioxidants such as BHT, BHA or tocopherols may be added to stabilise the active compound within the bait. A controlled release system for the 25 compound of general formula I may be employed where desirable. Preferably, the bait matrix includes added toxins such as chitin synthesis inhibitors, insect growth regulators and other termiticides. Alternatively, termiticidal 30 substances can be applied to the bait matrix once it has been deployed in the field and has attracted a significant number of termites. In either case, it is preferred that the toxin be slow-acting and non-repellent so as to be WO00/36914 PCT/AU99/01033 11 transported into the nest by foragers and there distributed throughout the colony either via food exchange or mutual grooming between the nest mates. According to a fifth aspect of the present invention 5 there is provided a termiticidal composition comprising: (1) a termiticidal substance; and (2) a feeding stimulant as described above. According to a sixth aspect of the present invention there is provided a compound having at least two OR groups, 10 each of which is a substituent of an aryl moiety, and R is hydrogen or an organic group, and addition compounds thereof, when used for stimulating feeding activity in termites. According to a seventh aspect of the present invention 15 there is provided a compound having at least two OR groups, each of which is a substituent of an aryl moiety, and R is hydrogen or an organic group, and addition compounds thereof, when used to attract termites to a locus. According to an eighth aspect of the present invention 20 there is provided the use of a compound having at least two OR groups, each of which is a substituent of an aryl moiety, and R is hydrogen or an organic group, and addition compounds thereof, in stimulating feeding activity in termites. 25 According to a ninth aspect of the present invention there is provided the use of a compound having at least two OR groups, each of which is a substituent of an aryl moiety, and R is hydrogen or an organic group, and addition compounds thereof, in attracting termites to a locus. 30 According to a tenth aspect of the present invention there is provided the use of a compound in the manufacture of a bait for attracting termites, said compound having at least two OR groups, each of which is a substituent of an WO00/36914 PCT/AU99/01033 12 aryl moiety, and R is hydrogen or an organic group, and addition compounds thereof. According to an eleventh aspect of the present invention there is provided the use of a compound in the 5 manufacture of a termiticidal composition, said compound having at least two OR groups, each of which is a substituent of an aryl moiety, and R is hydrogen or an organic group, and addition compounds thereof. Typically, the compound having at least two OR groups 10 is a compound of general formula I as described above. It has been found that para-hydroquinone is the natural feeding stimulant, but exists in the labial glands of termites almost entirely as its glucose conjugate, 4 hydroxyphenyl-B-D-glucopyranoside, which is commonly called 15 B-arbutin. P-Arbutin and glucose conjugates of the other compounds of general formula I may also be used in the invention described above. In particular, p-arbutin or glucose conjugates of the other compounds of formula I can be incorporated into a bait matrix and, through slow decay 20 generating an active compound of general formula I, could act as a slow-release system. BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the invention will now be 25 described, by way of example only, with reference to the following examples. Example 1 - Use of Labial Glands Extracts as Termite Attractants 30 In order to prepare labial gland extracts, termites were killed and the paired labial glands were removed. The labial glands were disrupted by freezing them for 15 minutes at -20"C and extracted with 0.6 ml of water for 12 WO 00/36914 PCT/AU99/01033 13 hours at room temperature. Then the extract was frozen at -20 0 C until used. The labial gland extracts prepared and tested are listed in Table I. Each extract was chemically analysed for the presence of para-hydroquinone, and it was 5 found to be present in all. Selected extracts were used in a bioassay to establish feeding choice, as indicated in Table 1, below. Table 1: Labial gland extracts prepared and tested No. of glands Chemically Termite species No. of glands Chemically Bioassayed Extracted Analysed Kalotermes flavicollis 40 + Cryptotermes brevis 70 + + Mastotermes darwiniensis 30 + + Hodotermes mossambicus 40 + Zootermopsis angusticollis 40 + Reticulitermes flavipes 70 + + Reticulitermes santonensis 70 + + Heterotermes indicola 120 + Schedorhinotermes lamanianus 60 + Coptotermes formosanus 70 + + Coptotermes acinaciformis 80 + + Nasutitermes nigriceps 60 + Nasutitermes exitiosus 70 + + Trinervitermes trinervoides 30 + Macrotermes subhyalinus 40 + 10 The methodology employed in the choice tests was that used by Reinhard et al. supra. In these experiments the termites were housed in a suitable container with access via a silicone tube to a foraging arena. In each experiment 15 two semicircles of moist filter paper (2.5cm in diameter) were placed close beside each other in the arena. One of the two semicircles was randomly chosen for application of one of the 25pl aliquots of labial gland extract and then WO00/36914 PCT/AU99/01033 14 moistened with water. The other semicircle was just moistened. Feeding in termites is expressed by gnawing behaviour, which can be easily recognised by the hypognathous head positions wherein the termites bore their 5 mandibles into the food and wriggle their heads trying to tear off little pieces, which they can then transport back to the nest. The distribution of the first 20 gnawing/feeding termites on the semicircles was registered. For example, it 10 was observed that 19 of 20 Mastotermes darwiniensis termites responded by gnawing and eating the filter paper treated with one equivalent of its labial gland secretion while only one termite responded to the control. Similarly, 18 of 20 C. acinaciformis termites responded by 15 gnawing and eating the filter paper treated with 2.5 equivalents of its labial gland secretion while 2 responded to the control. A further important observation was that termites of selected species also responded strongly in the bioassay to labial gland secretion from an unrelated 20 species. For instance, C. acinaciformis termites responded to a test paper treated with one equivalent of M. darwiniensis gland secretion while M. darwiniensis termites responded to a test paper treated with 2.5 equivalents of C. acinaciformis gland secretion. These results 25 demonstrate that the labial gland extract is a non-specific feeding stimulant for termites. The results are summarised in Table 2.

WO 00/36914 PCT/AU99/01033 15 Table 2: Natural lures Origin of labial Quantity of Termite species gland extract (gland Response Responding to lure Extract equivalents) M. darwiniensis M. darwiniensis 1 +++ C.acinaciformis 2.5 +++ C.acinaciformis M.darwiniensis 1 +++ C.acinaciformis 2.5 +++ An analysis of the labial gland extract shows that para-hydroquinone is present at low levels, usually less 5 than 10 -1 grams per gland, but is present at much higher concentrations in the saliva. f-arbutin is present in high concentrations in the glands but is no longer evident in the saliva. Presumably B-arbutin is broken down enzymatically into para-hydroquinone and glucose during 10 release of the termite's saliva, hence it was postulated that para-hydroquinone was the principal chemical feeding stimulant. Example 2 - Synthetic Compounds as Termite Attractants 15 Feeding choice tests were conducted with para hydroquinone and a number of related chemical substances in the manner described above in Example 1. The experimental data is summarised in Table 3.

WO 00/36914 PCT/AU99/01033 16 Table 3: Synthetic lures Termite species Quantity responding to Compound in Response lure Lure[ng] M.darwiniensis p-hydroquinone 5 +++ Quinhydrone 5 ++ Catechol 5 -/+ Resorcinol 5 + Phloroglucinol 5 -/+ 4-methoxyphenol 5 + Methoxyhydroquinone 5 + 1,4-dimethoxybenzene 5 ++ 4-phenoxyphenol 5 -/+ phenylhydroquinone 5 + polyphenylether* 5 + 4-benzyloxyphenol 5 -/+ C.acinaciformis p-hydroquinone 1 +++ quinhydrone 5 ++ catechol 5 ++ resorcinol 5 ++ phloroglucinol 5 ++ 4-methoxyphenol 5 + methoxyhydroquinone 5 + 1,4-dimethoxybenzene 5 + 4-phenoxyphenol 5 -/+ phenylhydroquinone 5 polyphenylether* 5 4-benzyloxyphenol 5 S.actuosus p-hydroquinone 5 +++ C.brevis p-hydroquinone 5 +++ N.exitiosus p-hydroquinone 5 +++ R.santonensis p-hydroquinone 5 +++ R.flavipes p-hydroquinone 5 +++ C.formosanus p-hydroquinone 5 +++ * Mixture comprising mainly a pentamer of p hydroquinone, but including dimer and trimer of p 5 hydroquinone as impurities.

WO00/36914 PCT/AU99/01033 17 When synthetic lures were tested, none of the principal labial gland constituents (glucose, inositols, P arbutin) elicited any feeding stimulation, except at unnaturally high concentrations where they probably served 5 a nutritional role as food supplements. However p hydroquinone elicited feeding stimulation at natural trace levels in the laboratory bioassays. For instance the threshold for attraction was 5 nanograms p-hydroquinone (50 picomoles) for M. darwiniensis and 100 picograms p 10 hydroquinone (1 picomole) for C. acinaciformis. Thus, there are different lower thresholds of feeding stimulation for different termite species. Synthetic compounds somewhat related in molecular structure to hydroquinone also elicited feeding responses 15 from M. darwiniensis and C. acinaciformis in the laboratory bioassays, as shown in Table 3. Example 3 - Mode of Attraction The mode of attraction of termites to the para 20 hydroquinone source may well include both olfactory and gustatory stimulation. The attractivity of para hydroquinone over distance (olfactory perception) was tested both in empty and sand-filled plastic arenas (ID 14.5 cm, height 1 cm, covered with a glass plate), which 25 were attached via a silicone tube to the housing container of the termites. Tests were carried out with M. darwiniensis and C. acinaciformis. Per test, two treated filter papers (25ng - 25pg p-hydroquinone and water as control, respectively) were placed in opposite positions in 30 the arenas. The direction of the tunnel/galleries built and the behaviour of a foraging termites in reference to the position of the filter papers were evaluated. In all tests both termite species built tunnels/galleries in direction WO00/36914 PCT/AU99/01033 18 to the p-hydroquinone-treated filter paper, never towards the control filter paper. When foraging the termites usually walked slowly in a zigzag way, but when in proximity of the source of p-hydroquinone (ca. 5-6 cm), 5 their behaviour changed suddenly: they walked straight and fast to the treated filter paper. Based on these observational data we concluded that the vapour of p hydroquinone creates an "active space" of several centimetres, which once perceived directs the termites 10 towards the source of the vapour by the concentration gradient. This active space did not get larger with increased p-hydroquinone concentration. Example 4 - Choice Feeding Tests 15 Laboratory colonies of Mastotermes darwiniensis and Coptotermes acinaciformis have been tested in a choice feeding test (mimicking an actual bait situation in the field) with pieces of Eucalyptus regnans wood (ca. 3.5g). The colonies (ca. 500 termites in M. darwiniensis, 2000 20 termites in C. acinaciformis) were housed in plastic containers. Plastic arenas of 5cm diameter, 3.5cm high were attached with perspex tubes on opposite sides of the colony container. In these arenas the wood was offered: one treated with 20ng p-hydroquinone, dissolved in water, 25 the other just moistened as control. The wood was dried and weighed before and after the test, the difference in weight as the amount eaten by termites was analysed after 3 days, 1 week and 4 weeks. After 3 days and one week both M. darwiniensis and C. 30 acinaciformis had eaten significantly more of the wood treated with the feeding stimulant than of the control (See Table 4). After 4 weeks the effect was gone. Therefore p hydroquinone does act as feeding stimulant in a choice WO 00/36914 PCT/AU99/01033 19 feeding test, although as only a little p-hydroquinone was applied, the effect was only short-term. This could be improved when testing the signal in the field under natural conditions and with complete termite colonies. 5 Table 4: Laboratory choice feeding tests with Mastotermes darwiniensis and Coptotermes acinaciformis: Amount wood eaten [g] after 3 days, one week and four weeks, comparing wood treated with 20ng p-hydroquinone to control (mean + 10 sd, n=20, Wilcoxon-Matched-Pairs-Test, ***: significant difference at p<0.001, n.s.: no significant difference). Duration of Treated wood Control wood Species P trial eaten [g) eaten [g] 3 days 0.234±0.139 0.121±0.108 *** M.darwiniensis 1 week 0.737±0.557 0.506±0.527 ** 4 weeks 2.397±0.968 2.255±0.918 n.s. 3 days 0.056±0.0.36 0.032±0.033 ** C.acinaciformis 1 week 0.185±0.159 0.096±0.109 ** 4 weeks 1.162±0.851 1.209±0.929 n.s. Example 5 - Field Trials Colonies of Coptotermes lacteus (ACT), Coptotermes 15 acinaciformis (NT) and Mastotermes darwiniensis (NT) have been used for large baiting trials in the field. Furthermore Coptotermes frenchi (ACT), Nasutitermes exitiosus (NSW) , Schedorhinotermes actuosus (NT), Coptotermes travians (Malaysia) and Coptotermes 20 curvignathus (Malaysia) have been tested exemplarily at infestation sites in urban areas and in the field. Paper towel of ca. 10g was used as bait matrix. It was either treated with 20pg hydroquinone (dissolved in water) or moistened with water only (=control). The paper was folded 25 and stuffed in plastic tubes. Termites had access to the bait material through holes drilled into the tubes. One WO00/36914 PCT/AU99/01033 20 treated and one control bait each were placed at feeding/infestation sites of the field colonies. In case of the larger field trials, up to 24 colonies per species had been selected, and drums filled with wood had been dug 5 into the soil around colonies as feeding sites. Baits were placed on top of the infested drums and covered with plastic foil and soil. In case of the exemplary trials single infestation sites have been selected and the baits were attached directly onto the infestation and covered 10 with plastic foil and soil, or cardboard to ensure minimum disturbance. Baits were checked after 1 to 4 days or after 2 weeks, depending on species and activity. The amount of paper eaten and the number of termites were analysed. As usual in natural field colonies there was a strong 15 variation of data between colonies, therefore for statistical analysis data had to be transformed into log and square root, respectively. In the large field trials C. lacteus, M. darwiniensis and C. acinaciformis had all consumed significantly more of the bait material and there 20 were more termites attracted to the baits, when hydroquinone had been applied (See Table 5). The exemplary tests with C. frenchi, S. actuosus, C. travians and C. curvignathus all indicated increased feeding activity on treated baits over control baits (See Table 6). Tests with 25 N. exitiosus showed no feeding activity even after long exposure, due to the difficult dietary preferences of this species. However, we could still show increased termite presence in treated baits compared to control baits (See Table 6). We therefore conclude that hydroquinone in fact 30 acts also under natural conditions in the field as strong and effective attractant and feeding stimulant on various termite species, when added to baits.

WO 00/36914 PCT/AU99/01033 21 Table 5: Field baiting trials with Coptotermes lacteus (ACT), Coptotermes acinaciformis (NT) and Mastotermes darwiniensis (NT) . (W): Amount bait material eaten [g] and (No): number of termites [N} in baits, comparing baits 5 treated with 20pg hydroquinone to control baits (mean ± SE, Paired Samples T-test, ***: significant difference at p<0.001, data transformed to log or sqrt for statistical analysis). Species Trial N Treated Bait Control Bait P W[g) 0.392±0.156 0.181±0.099 *** C. lacteus 3 days 17 No[N] 269.7±169.1 198.9±147.7 *** W[g] 0.766±0.164 0.368±0.126 ** M.darwiniensis 2 days 12 No[N] 18.5±3.6 7.7±2.9 ** WEg] 0.056±0.010 0.035±008 ** C.acinaciformis 2 days 16 No[N] 120.6±29.5 84.1±20.0 *** WO 00/36914 PCT/AU99/01033 22 Table 6: Exemplary field baiting trials with Coptotermes frenchi (ACT), Schedorhinotermes actuosus (NT), Coptotermes travians (Malaysia), Coptotermes curvignathus (Malaysia) and Nasutitermes exitiosus (NSW). Proportion bait material 5 eaten [%] or termite presence, respectively, comparing baits treated with 20pg hydroquinone to control baits. Proportion Proportion eaten/termite eaten/termite Species Trial n presence (treated presence bait) (control bait) C. frenchi 2 weeks 3 30% 5% 90% 0% 30% 0% S. actuosus 4 days 1 5% 0% C. travians 1 day 2 20% 20% 60% 40% C. curvignathus 1 day 3 95% 20% 50% 5% N. exitiosus 2 weeks 4 Termites present Not touched Termites present Not touched Termites present Not touched Termites present Not touched INDUSTRIAL APPLICABILITY The compounds of the present invention are useful in 10 stimulating feeding activity in termites so as to enhance the effectiveness of termite baits.

Claims (47)

1. A feeding stimulant for stimulating feeding activity in termites, comprising a compound having at least two OR groups, each of which is a substituent of an aryl moiety, 5 and R is hydrogen or an organic group, and addition compounds thereof.

2. A feeding stimulant as claimed in claim 1 wherein at least one R is an organic group and said compound has 10 feeding stimulating activity.

3. A feeding stimulant as claimed in claim 2 wherein said organic group is selected from the group consisting of alkyl, substituted alkyl, aryl, substituted aryl, aralkyl 15 and substituted aralkyl.

4. A feeding stimulant as claimed in claim 1 wherein at least one R is an organic group and said compound is a precursor of a compound with feeding stimulating activity. 20

5. A feeding stimulant as claimed in claim 4 wherein said compound is hydrolysed to a compound in which said at least one R is hydrogen. 25

6. A feeding stimulant as claimed in claim 5 wherein said organic group is a carbohydrate moiety.

7. A feeding stimulant as claimed in claim 6 wherein said compound is P-arbutin. 30

8. A feeding stimulant as claimed in claim 1 wherein said compound has an aromatic nucleus substituted by said at least two OR groups. WO00/36914 PCT/AU99/01033 24

9. A feeding stimulant as claimed in claim 8 wherein said compound has the following general formula I: OR 1 5 R 1 R2 6 NN(I) R 5 R3 R 4 10 wherein RI is selected from the group consisting of hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, aralkyl and substituted aralkyl; R 2 , R 3 , R 4 , R 5 and R 6 are independently selected from the group consisting of hydrogen, hydroxyl, alkyl, 15 substituted alkyl, alkoxy, substituted alkoxy, aryl, substituted aryl, aryloxy, substituted aryloxy, alkaryl, substituted alkaryl, alkaryloxy and substituted alkaryloxy, or R 2 and R 3 together, R 3 and R 4 together, R4 and R5 together and/or R5 and R6 together form an aryl group; 20 provided only that least one of R 2 , R 3 , R4, R5 or R6 is hydroxyl, alkoxy, substituted alkoxy, aryloxy, substituted aryloxy, alkaryloxy or substituted alkaryloxy.

10. A feeding stimulant as claimed in claim 9 wherein RI 25 is selected from the group consisting of hydrogen, alkyl, aryl and alkaryl.

11. A feeding stimulant as claimed in claim 10 wherein RI is selected from the group consisting of hydrogen, methyl, 30 ethyl, phenyl and benzyl.

12. A feeding stimulant as claimed in claim 11 wherein RI is hydrogen. WO00/36914 PCT/AU99/01033 25

13. A feeding stimulant as claimed in any one of claims 9 to 12 wherein R 2 , R 3 , R4, R 5 and R 6 are independently selected from the group consisting of hydrogen, hydroxyl, alkyl, alkoxy, aryl, aryloxy, alkaryl, and alkaryloxy. 5

14. A feeding stimulant as claimed in claim 13 wherein R 2 , R 3 , R 4 , R 5 and R 6 are independently selected from the group consisting of hydrogen, hydroxyl, methyl, ethyl, methoxy, ethoxy, phenyl, phenoxy, benzyl and benzyloxy. 10

15. A feeding stimulant as claimed in claim 14 wherein R 2 or R 6 is hydroxyl.

16. A feeding stimulant as claimed in claim 14 wherein R 3 15 or R 5 is hydroxyl.

17. A feeding stimulant as claimed in claim 14 wherein R 4 is hydroxyl. 20

18. A feeding stimulant as claimed in claim 1 wherein said compound is selected from the group consisting of: p-hydroquinone quinhydrone catechol 25 resorcinol phloroglucinol 4-methoxyphenol methoxyhydroquinone 1,4-dimethoxybenzene 30 4-phenoxyphenol phenylhydroquinone 4-benzyloxyphenol WO 00/36914 PCT/AU99/01033 26

19. A feeding stimulant as claimed in claim 1 wherein said compound has a plurality of aryl moieties.

20. A feeding stimulant as claimed in claimed 19 wherein 5 each said aryl moiety is a benzene ring.

21. A feeding stimulant as claimed in claim 20 wherein said compound is a polyphenylether. 10

22. A feeding stimulant as claimed in any one of claims 1 to 21 further comprising a biologically acceptable carrier and/or extender.

23. A method of stimulating feeding activity in termites, 15 comprising the steps of: (1) providing a feeding stimulant as claimed in any one of claims 1 to 22; and (2) applying said feeding stimulant to a locus. 20

24. A feeding stimulant as claimed in claim 23 wherein there is a food source at said locus.

25. A method of attracting termites to a locus, comprising the steps of: 25 (1) providing a food source at said locus; (2) providing a feeding stimulant as claimed in any one of claims 1 to 22; and (3) applying said feeding stimulant to said locus. 30

26. A bait for attracting termites, comprising: (1) a food source; and (2) a feeding stimulant as claimed in any one of claims 1 to 22. WO00/36914 PCT/AU99/01033 27

27. A bait as claimed in claim 26 wherein said food source is a source of cellulose.

28. A bait as claimed in claim 27 wherein said food 5 source is selected from the group consisting of paper, cardboard, canite, chipboard, sound wood and fungally decayed wood.

29. A bait as claimed in any one of claims 26 to 28 10 further comprising a termiticidal substance.

30. A bait as claimed in claim 29 in which said termiticidal substance is a chitin synthesis inhibitor or an insect growth regulator. 15

31. A bait as claimed in any one of claims 26 to 30 further comprising an antioxidant.

32. A bait as claimed in any one of claims 26 to 31 20 further comprising a synergist and/or other attractants.

33. A bait as claimed in any one of claims 26 to 32 further comprising nutrients such as nitrogen-containing compounds and carbohydrates. 25

34. A termiticidal composition comprising: (1) a termiticidal substance; and (2) a feeding stimulant as claimed in any one of claims 1 to 22. 30

35. A termiticidal composition as claimed in claim 34 wherein said termiticidal substance is a chitin synthesis inhibitor or insect growth regulator. WO00/36914 PCT/AU99/01033 28

36. A compound having at least two OR groups, each of which is a substituent of an aryl moiety, and R is hydrogen or an organic group, and addition compounds thereof, when used for stimulating feeding activity in termites. 5

37. A compound as claimed in claim 36 of general formula I as defined in claim 9.

38. A compound having at least two OR groups, each of 10 which is a substituent of an aryl moiety, and R is hydrogen or an organic group, and addition compounds thereof, when used to attract termites to a locus.

39. A compound as claimed in claim 38 of general formula 15 I as defined in claim 9.

40. The use of a compound having at least two OR groups, each of which is a substituent of an aryl moiety, and R is hydrogen or an organic group, and addition compounds 20 thereof, in stimulating feeding activity in termites.

41. The use of a compound as claimed in claim 40 wherein said compound is of general formula I as defined in claim 9. 25

42. The use of a compound having at least two OR groups, each of which is a substituent of an aryl moiety, and R is hydrogen or an organic group, and addition compounds thereof, in attracting termites to a locus. 30

43. The use of a compound as claimed in claim 42 wherein said compound is of general formula I as defined in claim 9. WO 00/36914 PCT/AU99/01033 29

44. The use of a compound in the manufacture of a bait for attracting termites, said compound having at least two OR groups, each of which is a substituent of an aryl moiety, and R is hydrogen or an organic group, and addition 5 compounds thereof.

45. The use of compound as claimed in claim 44 wherein said compound is of general formula I as defined in claim 9. 10

46. The use of a compound in the manufacture of a termiticidal composition, said compound having at least two OR groups, each of which is a substituent of an aryl moiety, and R is hydrogen or an organic group, and addition 15 compounds thereof.

47. The use of a compound as claimed in claim 46 wherein said compound is of general formula I as defined in claim 9.