Sampling subterranean termite species diversity and activity in tropical savannas: an assessment of different bait choices

Abstract.  1. Cellulose baits are commonly used for semi-quantitative sampling of subterranean wood-feeding termites, with a single food choice sampling programme implemented most often. In most situations, however, the composition and feeding preferences of the subterranean termite assemblage remain unknown.
2. The diversity, frequency, foraging activity, and intensity of attack of termites were assessed regularly at 144 baits representing 12 different bait choices over 8.5 months, in two northern Australian tropical savanna sites that differed in vegetation structure (closed vs open). Baits differed in type (paper rolls, cardboard, wooden stakes), position (surface, buried), and moisture status at installation (wet, dry).
3. Sixteen species were recorded, including 11 wood-feeders. Average species diversity, foraging activity, and bait consumption were greater at buried baits than at surface baits. Wooden baits were most attractive early in the experiment, and paper baits more attractive later. Mean species diversity was greatest at wooden stakes in the closed site. Species frequency of occurrence varied across bait choices.
4. A composite bait sampling protocol of stakes and paper rolls installed above and below ground gave an accurate assessment of the activity, diversity, and structure of the termite guild sampled across all baits over 8.5 months.
5. The choice of bait, its presentation, and time of examination are critical to the success of a termite baiting programme. If the aim is to characterise the structure and foraging activity of the subterranean termite assemblages that are attracted to baits, composite baiting protocols should be implemented.     

Toxic effects of 2-deoxy-D-galactose on Coptotermes formosanus (Isoptera: Rhinotermitidae) and symbionts

In the interest of developing interventions to infestations by Formosan subterranean termites, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), several rare sugars were tested for effects on the termites and symbionts. Among these, the D-galactose analog, 2-deoxy-D-galactose (2deoxyGal) showed promise as a potential control chemical. At a test concentration of 2deoxyGal (320.4 microg/mm3) in water applied to 5-cm filter paper, in bioassays with 20 termite workers, we found that worker termite mortality was significantly affected over a 2-wk period. Subsequent dose-mortality feeding studies confirmed these findings. In addition, consumption of the sugar-treated filter paper by termites caused a significant decrease in hindgut protozoan populations. 2deoxyGal caused dose-dependent termite mortality, taking on average 1 wk to begin killing workers, indicating that it may have promise as a delayed action toxin, which, if added to baits, could allow time after bait discovery for an entire colony to be affected.     

Effect of Summon Preferred Food Source on feeding, tunneling, and bait station discovery by the formosan subterranean termite (Isoptera: Rhinotermitidae)

This study evaluated the effect of Summon Preferred Food Source on feeding, tunneling, and bait station discovery by the Formosan subterranean termite, Coptotermes formosanus Shiraki. Bioassays were conducted to determine whether Summon disks affected the aggregation and feeding behavior of termites and to determine whether the presence of Summon disks caused increased recruitment of termites to wood blocks. When termites encountered the disk, they immediately clustered on top of the disk. Termites were observed aggregating on top of the disk throughout the experiment. Consumption of Summon disks was significantly greater than consumption of cardboard disks in paired choice tests. The presence of a Summon disk on top of a wood block caused a significant increase in consumption of the wood block. Bioassays also were conducted to determine whether water extracts of Summon disks affected termite behavior. Consumption of filter paper disks treated with a water extract of Summon disks was significantly greater than consumption of control filter paper disks. Termites tunneled through sand treated with a water extract of Summon disks faster than they tunneled through untreated sand. In a field test, the rate of infestation of monitoring stations with a Summon disk was 3 times greater than the rate of infestations of stations without a disk.     

Bait matrix for delivery of chitin synthesis inhibitors to the formosan subterranean termite (Isoptera: Rhinotermitidae)

The efficacy of three chitin synthesis inhibitors, diflubenzuron, hexaflumuron, and chlorfluazuron, incorporated into a novel bait matrix to kill the Formosan subterranean termite, Coptotermes formosanus Shiraki, was evaluated in the laboratory. The bait matrix was significantly preferred by C. formosanus over southern yellow pine wood in a two-choice feeding test. Bait formulations containing 250 ppm of the three chitin synthesis inhibitors were presented to termite nests with 2,500 individuals (80% workers and 20% soldiers) in the presence of alternative food sources consisting of cardboard and southern yellow pine, Pinus taeda L., wood. None of the bait formulations were significantly repellent or feeding deterrent to the termite workers evidenced by the lack of full consumption of alternative food sources. All nests presented with the bait formulations died within 9 wk, whereas the control nests (bait with no chitin synthesis inhibitors) remained alive 6 mo after the end of the study. No significant differences in consumption were observed among the chitin synthesis inhibitor treatments. Importance of this study for the improvement of current bait technology is discussed.     

The effect of bait design on bait consumption in termites (Isoptera: Rhinotermitidae)

The efficacy of baiting as a pest control method relies on the bait appealing to the pest species. In the case of wood-eating termites, bait stations should be designed to encourage termite presence and to maximize their consumption of bait matrix in order to expedite control in minimal time. A field experiment examined the effect of bait size (one large bait or four small baits of equivalent total size, with commensurate inspection and replacement schedules), compaction (tightly rolled or loosely folded) and composition (paper only or paper plus wood) on termite presence and on untreated bait paper removal rates over four months. All three factors were significant, with bait size the most important factor, followed by compaction and then composition. The least effective baits were small, compacted (rolled) paper-only baits with monthly inspections; these had the highest abandonment rate (70%) and had the least paper removed (mean of 24 g). The most effective baits were large, folded paper-plus-wood baits with inspections at two months; these had the lowest abandonment rate (20%) and had the highest paper removal (mean of 112 g). The more than four-fold difference between these baits types demonstrates that bait efficacy can be altered considerably merely by changing bait design without adding new ingredients to the bait matrix.     

白蚁纤维素粉饵料成型技术研究

为研究白蚁饵料成型工艺,比较了9种胶黏剂对白蚁纤维素饵料成型效果、耐水性能以及对白蚁取食的影响。结果表明:20%、40%剂量糊精;50%、100%剂量三聚氰胺甲醛树脂,10%、20%、40%田菁胶、卡拉胶、壳聚糖、明胶;10%、50%、100%聚乙烯醇、硅酸钠对微晶纤维素的成型效果较好,经上述剂量胶黏剂处理后,纤维素饵块的邵氏硬度(HD)极显著高于对照。耐水性能试验至第30天时,50%聚乙烯醇、100%聚乙烯醇、100%三聚氰胺甲醛树脂处理的纤维素饵块的溃散程度指数分别为1.33、1.00、2.00,其余饵块的溃散程度指数均达3级。生测结果显示,在7 d的室内强迫取食试验中,白蚁对50%聚乙烯醇、100%聚乙烯醇、100%三聚氰胺甲醛树脂处理的块状纤维素饵料的取食率均极显著低于对照,说明饵块中添加的上述胶黏剂对白蚁的取食具有一定的影响。综上,50%聚乙烯醇、100%聚乙烯醇、100%三聚氰胺甲醛树脂适用于白蚁纤维素饵料成型,但若想获得白蚁喜食的饵块仍需对配方做进一步的优化。     

Effect of Bemisia tabaci honeydew and its carbohydrates on search time and parasitization of Encarsia bimaculata

Abstract:  The search time of Encarsia bimaculata Heraty et Polaszek was examined and recorded by using filter paper discs in Petri dish arenas impregnated with Bemisia tabaci (Gennadius) honeydew or its component carbohydrates. Our data show that E. bimaculata used honeydew as a contact kairomone to locate its host. Females responded quantitatively to the honeydew and the search time in the treated patches increased. This increase was concentration-dependent with regard to the amount of honeydew applied, but it levelled off 0.05 g/ml onwards. The response of E. bimaculata to honeydew decreased with increasing time after application and was significantly reduced 8 days after treatment. The parasitoid females were also arrested in patches treated with glucose, fructose, trehalulose and trehalose; trehalose elicited the highest response in the parasitoids. However, sucrose and low concentrations of melezitose did not elicit a significant effect. Glucose, sucrose, fructose, trehalose and trehalulose increased the longevity of the parasitoid females by a factor of 8.4, 8.1, 6.3, 6.1 and 4.2, respectively. Melezitose and 0.15 g/ml natural honeydew, however, had no effect on parasitoid lifespan. The effects of aqueous spray of honeydew sugars on egg to adult survivorship and parasitization of B. tabaci by E. bimaculata significantly differed when compared with controls only in cases where mixtures of glucose + fructose and trehalose and fructose + trehalose were applied.     

Utilizing rabbit immunoglobulin G protein for mark-capture studies on the desert subterranean termite, Heterotermes aureus (Snyder)

Mark-capture dispersal studies were conducted to investigate the feasibility of marking the southwestern desert subterranean termite, Heterotermes aureus (Snyder) with rabbit immunoglobulin G (IgG). In turn, short-range dispersal patterns of H. aureus were measured across a 20-m diameter desert landscape at three distinct field locations. Each location consisted of 51 termite feeding stations containing corrugated cardboard. The central feeding station (CFS) at each location was impregnated with rabbit IgG. A circular grid was then constructed around each CFS that consisted of 50 additional unmarked cardboard feeding stations strategically placed around the CFS at distances of 1.5, 2.0, 4.0, 7.0 or 10.0 m. Termites self-marked with rabbit IgG by feeding on the marked bait. The CFS and the 50 peripheral feeding stations were sampled for marked termites twice at each location 17–65 days after the marked bait was placed at the CFS to determine the spatial dispersal patterns of H. aureus within each research grid. Termites that self marked by feeding on rabbit IgG marked bait were detected by an anti-rabbit IgG enzyme-linked immunosorbent assay (ELISA). Generally, the CFSs contained the highest frequency of marked termites with 28.0% of the individuals assayed from the CFSs containing rabbit IgG. Over the course of the study, 39 of the unmarked peripheral feeding stations contained at least one marked termite. Of the termites assayed from the peripheral stations (n = 2,955), 124 or 4.2% of the individuals contained the mark. The average distance traveled by the marked termites collected at the peripheral feeding stations was 5.7 ± 3.3 m from the CFSs. We also examined single nucleotide polymorphisms (SNPs) from termites collected at each field site. Data indicated that each field site were genetically distinct and therefore non-related termites. We discuss the advantages and limitations of marking termites with rabbit IgG for dispersal studies.     

Termite Feeding by <Emphasis Type="Italic">Gorilla gorilla gorilla</Emphasis> at Bai Hokou,Central African Republic

Though insectivory by large-bodied gorillas may be unexpected, researchers have reported it in all populations of gorillas studied to date. Our study of 2 well monitored groups of western gorillas (Gorilla gorilla gorilla) at Bai Hokou in Dzanga-Ndoki National Park, Central African Republic provides information on frequency and variability of termite consumption (the most commonly eaten insect) as well as some of the first direct observations of the behavior. Pooled data from both groups indicate termite feeding on 34% and 83% of days, through fecal analysis and feeding trails, respectively. Direct observations revealed that termite feeding occurred on 91% of the days for 1 group, in which the silverback fed on termites during 13% of all feeding scans, making termites the most commonly observed food item. The group that had a higher density of termite mounds in its home range consumed termites more frequently than the other group did. A higher proportion of fecal samples from the silverbacks contained termite remains than the ones from adult females and juveniles. Termite consumption was lower during the dry season, but it does not correlate with rainfall, measures of fruit availability, or fruit consumption. Displacements at termite mounds occurred more than expected, indicating that they are a patchy, sought-after food resource. Gorillas did not use tools to extract termites, but they used 2 different techniques to remove them from the cells. Though culture or social traditions may cause the variation in termite consumption across sites, further investigation of termite availability and consumption is necessary to rule out ecological and methodological explanations for observed variations.     

Methods to mark termites with protein for mark–release–recapture and mark–capture type studies

Studies were conducted to investigate the feasibility of marking the southwestern desert subterranean termite, Heterotermes aureus (Snyder), with rabbit immunoglobulin G (IgG) protein for mark–release–recapture (MRR) and mark–capture type studies. Qualitative laboratory studies were conducted to determine how long reagent-grade rabbit IgG is retained on or in H. aureus that were marked either externally with a topical spray, internally by feeding them a rabbit IgG-marked food source, or both internally and externally (double marked). Marked termites were detected by an anti-rabbit IgG enzyme-linked immunosorbent assay. Data indicated that the termites retained the mark for at least 35 days, regardless of the marking procedure. A second series of laboratory studies were conducted to determine how fast H. aureus acquire the mark after feeding on cardboard bait that was either sprayed or soaked in different formulations of rabbit IgG. The IgGs tested were a highly purified and costly reagent grade IgG at 5.0 mg/ml and a less pure and less costly technical grade rabbit IgG at 1.0 mg/ml. The results showed that termites acquired both marks equally well after exposure to the soaked cardboard treatment. The advantages and limitations of protein marking termites with rabbit IgG for MRR or mark–capture termite studies are discussed.     

Development of a biological control-based Integrated Pest Management method for Bemisia tabaci for protected sweet pepper crops

The tobacco whitefly, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae), is a key pest in commercial sweet pepper crops in southeast Spain. Its biological control is currently based on augmentative introductions of the parasitic wasp Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae), which need to be occasionally supplemented with pesticide applications. These pesticides can be harmful for the biological control agents. Therefore, it is important to improve the current strategy by reducing dependency on pesticides. Two potential solutions are conceivable: addition of another effective biocontrol agent or application of pesticide prior to the release of biocontrol agents. The mirid bug Nesidiocoris tenuis Reuter (Heteroptera: Miridae) and the predatory mite Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) are promising candidates as additional biocontrol agents. The aim of the present study was to test these possible solutions in two subsequent trials, i.e., a 'selection' and an 'improvement' experiment. In the selection experiment, four treatments were compared: E. mundus , N. tenuis  +  E. mundus , A. swirskii  +  E. mundus , and A. swirskii  +  N. tenuis  +  E. mundus . Amblyseius swirskii appeared able to significantly increase effectiveness against the pest, in contrast to N. tenuis, which did not contribute to whitefly control. The best strategy was the combination of E. mundus and A. swirskii . In the improvement experiment, three treatments were compared: E. mundus , A. swirskii  +  E. mundus , and A. swirskii  +  E. mundus +  pesticides. Amblyseius swirskii again proved capable of significantly reducing whitefly populations, and the implementation of pesticides before the release of the biocontrol agents was shown to increase the effectiveness against the pest even more.     

A comparison of two methods for sampling assemblages of subterranean,wood-eating termites (Isoptera)

Abstract Within a 50 × 50 m area of wandoo Eucalyptus capillosa woodland in the Western Australian wheatbelt, the diversity and frequency of occurrence of wood-eating termite species was assessed at two food types. Over a 12 month period, monthly termite activity was determined: (i) at sound/undecayed artificial baits (seasoned wooden stakes of Jarrah, Karri, Pine, Batu, Oregon; Jarrah sawdust; paper rolls); and (li) at naturally occurring timber, fallen logs and branches of wandoo, in varying stages of decay. Termite diversity was 11 species at baits, 18 species at wandoo out of an overall site richness of 21 species. Karri attracted the most species (9); sawdust attracted none. At wandoo, Nasutitermes exitiosus, Coptotermes acinaciformis and Occasitermes occasus accounted for 59% of samples where termites were recorded. At baits, Heterotermes occiduus accounted for a mean of 80% of samples across bait types, but was rarely sampled at wandoo (5% of samples). Only H. occiduus, C. acinaciformis and Amitermes neogermanus ate bait. Pine, Oregon and paper rolls were most effective in attracting foraging termites in terms of highest per cent of replicates showing bait consumption and highest consumption rates. Jarrah and Batu were least attractive to foraging termites. Samples from wandoo underestimated the relative frequency of occurrence of H. occiduus within the study site. Coptotermes acinaciformis, which attack large food items, and certain species of Amitermes, which forage on subterranean food, may have been underestimated by both sampling methods. These findings indicate that a proper understanding of the structure of wood-eating termite assemblages within a given area requires a composite sampling strategy which addresses termites that eat sound or decayed wood, as well as surface and subsurface foragers.     

Protozoacidal Trojan-Horse: Use of a Ligand-Lytic Peptide for Selective Destruction of Symbiotic Protozoa within Termite Guts

For novel biotechnology-based termite control, we developed a cellulose bait containing freeze-dried genetically engineered yeast which expresses a protozoacidal lytic peptide attached to a protozoa-recognizing ligand. The yeast acts as a ‘Trojan-Horse’ that kills the cellulose-digesting protozoa in the termite gut, which leads to the death of termites, presumably due to inefficient cellulose digestion. The ligand targets the lytic peptide specifically to protozoa, thereby increasing its protozoacidal efficiency while protecting non-target organisms. After ingestion of the bait, the yeast propagates in the termite''s gut and is spread throughout the termite colony via social interactions. This novel paratransgenesis-based strategy could be a good supplement for current termite control using fortified biological control agents in addition to chemical insecticides. Moreover, this ligand-lytic peptide system could be used for drug development to selectively target disease-causing protozoa in humans or other vertebrates.     

Elimination of subterranean termite (Isoptera: Rhinotermitidae) colonies using a refined cellulose bait matrix containing noviflumuron when monitored and replenished quarterly

Using a quarterly (3-mo) monitoring and bait-replenishment interval, 122 subterranean termite colonies throughout the United States were baited with a refined cellulose bait matrix containing 0.5% noviflumuron. All colonies were eliminated in less than 1 yr after initiation of baiting as determined by long-term monitoring and genetic markers. Sixty-three percent of the colonies were eliminated during the first quarter after the initiation of baiting and 77% of colonies were eliminated after consuming two bait tubes or less. This suggests that a single baiting cycle and bait installed in response to a single active monitoring device were sufficient to eliminate the majority of colonies. Although termites temporarily abandoned stations after depleting bait, workers resumed feeding when baits were replenished. Colonies that consumed large amounts of bait before elimination foraged into multiple stations, thus allowing adequate amounts of bait to sustain feeding. The time to eliminate termite colonies with bait replenished quarterly was similar to that previously reported for laminated cellulose bait replenished monthly. Our data support the conclusion that extending the bait replenishment interval from monthly to quarterly for bait tubes with refined cellulose containing 0.5% noviflumuron did not adversely impact colony elimination.     

Feeding site selection by workers of the Formosan subterranean termite Coptotermes formosanus (Isoptera: Rhinotermitidae) - a re-analysis of field data from a mark-recapture study

During the early stages of the development of termite baits, dyed paper was placed in specified feeding stations to ascertain whether a slow-acting toxicant could be placed in a few bait stations to be delivered to the entire colony members of the Formosan subterranean termite, Coptotermes formosanus Shiraki. Feeding frequency data, as measured by the dye concentration in individual termites, suggested the absence of feeding site fidelity. However, these results were often misinterpreted as random movement of termites that were marked and released for population estimate studies, or the random search of food in soil by subterranean termites. A computer simulation program was constructed to re-examine this feeding frequency data, and confirmed the earlier conclusion that the lack of feeding site fidelity was the most likely explanation for the data.     

Feeding, uptake, and utilization of carbohydrates by western subterranean termite (Isoptera: Rhinotermitidae)

Western subterranean termite, Reticulitermes hesperus (Banks), prefers various mono-, di-, and trisaccharides, total feeding being the greatest on paper disks treated with 5% ribose followed by 3% xylose, 2% maltose, 2% fructose, 2% arabinose, and 2% ribose. In multiple choice tests, termites were not able to discriminate between 2% ribose, 2% fructose, 2% xylose, and 2% maltose. Termites readily take up [14C] sucrose in feeding studies. Most of the sucrose is used as an energy source for respiration (89.2%), a very small proportion remains within the termite (9.3%), and an even smaller amount is excreted as solid waste (1.5%). The amount of 14C label transferred to other colony members via trophallaxis, body contact, or grooming is small and directly dependent upon the time and numbers of donors and recipients. At day 15 postmixing, the percentage of transfer was highest, 14.4 and 15.1% for both 1:1 and 2:1 donor to recipient mixing ratios, respectively. The mean amount of labeled 14C received by recipients increased from seven disintegrations per minute (dpm) on day 2 to 30 dpm on day 15 for 1:1. Overall mean radioactivity recovered from recipient termites when mixed with donor termites at 1:1 ratio (20 dpm) was significantly less than (28 dpm) when mixed with donor termites at 2:1 ratio. Sugars act as phagostimulants to the termites at concentrations much higher to those that termites naturally encounter in wood. Termites readily metabolize carbohydrates such as sucrose, and thus their use in bait matrices may increase consumption and retention at bait stations.     

Effect of wood hardness and secondary compounds on feeding preference of Odontotermes formosanus (Isoptera: Termitidae)

Odontotermes formosanus (Shiraki) (Isoptera: Termitidae) is one of the most destructive plant pests in China, which control relies mainly on baits strategies. Baits made from the wood of eight different tree species were used to study the feeding preference of this termite, and conversely wood protection strategies of the tree species. Three bait types were used to identify wood protection strategies: solid wood (physical and chemical protection), crude flour (chemical protection) made from ground wood, and extracted flour (no protection) made by extracting crude flour with ethanol and toluene. Feeding preference was influenced by wood species and bait type. For solid wood, Magnolia denudata Desr (75%) and Elaeocarpus glabripetalus Merr (41%) were most preferred; for crude flour, E. glabripetalus (97%) and Quercus variabilis Blume (92%) were most preferred; and for extracted flour, there were no significant differences between wood species, demonstrating the influence of chemical defense. The greatest contrast between bait types was for Platanus orientalis L, the least preferred as solid wood and crude flour, suggesting that chemical defense compounds are particularly important in this species. Solid wood consumption was inversely correlated with wood density. Extracted flour consumption was positively correlated with glucose concentration. There was no direct effect of holocellulose and other components tested. O. formosanus preferred to fed on soft wood with low chemical protection (M. denudata); conversely trees protected their wood either physically [e.g., E. glabripetalus, Q. variabilis, Cinnamomum camphora (L.) Presl, and Ligustrum lucidum Aiton] or chemically (Populus bonati Levl) or a combination of both strategies (Liquidamba formosana Hance and P. orientalis).     

Evaluation of different woods against fungus-growing termite Odontotermes obesus (Rambur) (Blattodea: Termitidae: Macrotermitinae) for use in bait stations

Fungus-growing termites are important pests in buildings and agriculture in Pakistan and are difficult to control with existing bait systems. Development of bait systems requires the knowledge of foraging behavior of termite species. Behavior of foraging workers depends upon the quality and quantity of the food placed in the bait stations. In the current study, we tested 16 different woods (of varying density) for their susceptibility to an important fungus-growing termite, Odontotermes obesus (Rambur). The aim was to find a highly susceptible wood for use in bait stations. The woods were evaluated in no-choice and choice feeding experiments in the field by mass loss and visual ratings to the termites. Statistically significant differences were recorded (P?<?.001). Woods having low density were preferred to high density woods. Highest mass losses (%) were recorded from Ficus religiosa (86.49–87.8%), Bombax malabaricum (86.53–88.43%) and Populus euramericana (75.62–76.31%) in both no-choice and choice tests under “very heavy attack (almost collapsed) to completely consumed” visual rating category. The woods having least mass losses were Albizia lebbeck heartwood (7.03–9.91%), Syzygium cumini (14.25–19.89%) and Dalbergia sissoo heartwood (14.35–24.88%) and had “slightly to superficial attack” with minimum rating values. Ficus religiosa, B. malabaricum and P. euramericana appear suitable woods for use in bait stations for fungus-growing termites.     

Evaluation of hexaflumuron for controlling the subterranean termite Coptotermes curvignathus (Isoptera: Rhinotermitidae) in Malaysia

Cellulosic bait matrices containing 0.5% hexaflumuron were tested against field colonies of the subterranean termite Coptotermes curvignathus Holmgren in Malaysia. Foraging activities of the termites were first monitored for several months by using survey stakes and wood bundles placed in underground monitoring traps. Infested stakes were replaced with bait devices. Termite workers to act as recruits were collected from infested stakes and placed in the bait devices. Subsequent activities of the termites were monitored by examining and weighing the wood in the monitoring traps. Data show that the four colonies had populations of 166,288-709,052 foragers and mean wood consumption rates of 305.9-508.2 g/mo per trap. These colonies ceased their activities at all monitoring devices 25-44 d after baiting had commenced. Colonies consumed approximately 27-79 g of bait matrix or 137.5-395 mg of hexaflumuron. Thus, C. curvignathus colonies could be monitored, characterized, baited, and foraging eliminated by using a bait matrix containing hexaflumuron.     

Field evaluation of potential control strategies against the invasive eastern subterranean termite (Isoptera: Rhinotermitidae) in Chile

Four different termite control strategies consisting of two soil treatments with cypermethrin and fipronil and two bait treatments with hexaflumuron and sulfluramid were evaluated for their efficacy and potential for controlling the invasive eastern subterranean termite, Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae), in Quillota and Valparaiso, Chile. Monitoring stations were installed at all sites to measure the overall termite activity next to and at distances up to 30 m away from infested structures, most being 3-5 m. Foraging activity was extremely seasonal with the maximum consumption rates occurring from January to April. Termite foraging activity was low from July to September. After treatments in January 2003, there was a significant decrease in wood consumption, percentage of active stations, and numbers of termites in traps for the first 6 mo with hexaflumuron baits. No significant change in R. flavipes foraging activity was observed on wood consumption and percentage of active stations for sulfluramid bait or cypermethrin and fipronil soils treatments. The seasonal pattern of foraging activity remained unchanged for all treatments in 2004 and 2005, except structures baited with hexaflumuron. Feeding activity at the monitors in the area surrounding the hexaflumuron baits declined to 0 after January 2004. Alate flights occurred in approximately 38% of the structures treated with cypermethrin and sulfluramid bait in 2003 and in approximately 40% of the structures treated with cypermethrin, fipronil, and sulfluramid bait in 2004. Sulfluramid baits and cypermethrin soil treatments did not have any impact within a 15-m radius of the structures. Soils treatments of fipronil and cypermethrin prevented termites access in 75% of the homes. The number of active monitoring stations only declined within 2 m of the fipronil-treated zone. Hexaflumuron exhibited a reduction in activity for at least a 15-m radius.