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We determined the impact of imidacloprid (Premise) on colonies of Reticulitennes spp. (Isoptera: Rhinotermitidae) through soil applications in the field. We selected 11 houses in the Raleigh, NC, area with active termite infestations. In–ground monitoring stations (mean = 75.9 stations) were installed around each house, and samples of termites visiting the monitors, in mud tubes, as well as samples from wood debris in the yard, were collected monthly for up to 14 mo to determine the numbers and locations of colonies present before treatment. We used microsatellite genetic markers to identify individual colonies present on each property. All houses were treated with Premise 75 WSP by using an exterior perimeter⁄interior spot treatment. After treatment, termite samples were collected monthly for 3 mo and then quarterly for 2 yr to track the fate of colonies. Of the 12 treated colonies (those attacking structures), 75% disappeared within 90 d and were not detected again. In contrast, only 25% of 48 untreated colonies (located 2 m or further from the treatment zone) and 40% of the six likely treated colonies (located within 0.5 m of the treatment zone but not known to be attacking the structure) were not detected again during the study. Our findings are consistent with strong colony–level effects of soil treatments with imidacloprid, resulting in the suppression or elimination of Reticulitermes spp. colonies in many cases. [ABSTRACT FROM AUTHOR]

Onset of abnormal behaviors, morbundity, and death was evaluated in eastern subterranean termites, Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae), exposed to several concentrations (45,90, 135, and 180 ppm) of indoxacarb and to several (5, 10,20,40,80, and 160 mm) exposure periods. Abnormal behaviors, morbundity, and death occurred in a predictable sequence: disorientation, ataxia, and morbundity followed by death. In general, higher concentrations and longer exposure periods resulted in faster onset of abnormal behaviors, morbundity, and death. The average onset time of abnormal behaviors, morbundity, and death was faster for groups of termites compared with individuals exposed to similar concentrations and periods of contact. The importance of onset times of abnormal behaviors as another important measure of the toxicity of slow–acting toxicants is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Neuropeptide F (NPF)-like immunoreactivity was previously found to be abundant in the eastern subterranean termite, Reticulitermes flavipes. Purification of the NPF from a whole body extract of worker termites was accomplished in the current study by HPLC and heterologous radioimmunoassay for an NPF-related peptide, Helicoverpa zea Midgut Peptide-I. A partial amino acid sequence allowed determination of the corresponding cDNA that encoded an open reading frame deduced for authentic R. flavipes NPF (Ref NPF): KPSDPEQLADTLKYLEELDRFYSQVARPRFa. Effects of synthetic NPFs on muscle contractions were investigated for isolated foreguts and hindguts of workers, with Drm NPF inhibiting spontaneous contractions of hindguts. Phylogenetic analysis of invertebrate NPF sequences reveals two separate groupings, with Ref NPF occurring within a clade composed exclusively of arthropods. [Copyright &y& Elsevier]

Eastern subterranean termite, Reticulitermes flavipes (Kollar), workers were continuously exposed to one of five chitin synthesis inhibiting (CSI) active ingredients and the protist community from the hindgut quantified biweekly for 21 d. The CSIs tested included commercially available formulations of diflubenzuron, hexafiumuron, lufenuron, noviflumuron, and novaluron. Results showed termites exposed to CSIs had a significant decrease (⩾30%) in the estimated total protist population after 3 d, regardless of treatment. Protist species impacted were Dinenympha fimbriata, D. gracilis, Microjoenia fallax, Pyrsonympha vertens, and Trichonympha agilis and could be indicative of weakened digestive homeostasis, but further studies are needed. We also provide evidence that lufenuron is highly toxic and discuss some of the implications this might have on termite management practices. [ABSTRACT FROM AUTHOR]

The chloro-nicotinyl insecticide imidacloprid is used extensively as a soil treatment against subterranean termites. We conducted the first study of the metabolic fate of imidacloprid in termites, by exposing workers of the eastern subterranean termite, Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae) to radiolabeled imidacloprid through topical application and ingestion. Several days after topical application, we detected up to 11 radiolabeled compounds. The parent compound, IMI, and the following six metabolites were identified by liquid chromatography/mass spectrometry: olefin-imidacloprid (major metabolite), 4/5-OH imidacloprid, 4,5-di-OH imidacloprid, des-nitro olefin imidacloprid, des-nitro imidacloprid, and a glucuronide conjugate of des-nitro imidacloprid (des-nitro IMI-glu). Over time, detoxification of imidacloprid proceeded from less polar to more polar compounds, with des-nitro IMI-glu seeming to be the ultimate, major end product in surviving termites. Degradation of imidacloprid was limited to internal tissues of the termite. Workers fed wood treated with imidacloprid or provided with a treated substrate (sand) had metabolitic profiles similar to topically treated termites. Termites fed imidacloprid or exposed to it in soil excreted detectable amounts of all of the identified metabolites. Finally, we determined that imidacloprid metabolites were less toxic to termites than imidacloprid itself. Only the olefin-imidacloprid and 5-OH imidacloprid caused morbidity in termites exposed to sand treated with these compounds, but at concentrations ≈10-20-fold higher than the parent imidacloprid. Our results shed light on the metabolic pathway used by termites to detoxify imidacloprid and show how metabolism plays a key role in determining the availability of the active ingredient and its various metabolites for transfer among workers within the colony. [ABSTRACT FROM AUTHOR]

Background: Termites (Isoptera) are eusocial insects whose colonies consist of morphologically and behaviorally specialized castes of sterile workers and soldiers, and reproductive alates. Previous studies on eusocial insects have indicated that caste differentiation and behavior are underlain by differential gene expression. Although much is known about gene expression in the honey bee, Apis mellifera, termites remain relatively understudied in this regard. Therefore, our objective was to assemble an expressed sequence tag (EST) data base for the eastern subterranean termite, Reticulitermes flavipes, for future gene expression studies. Results: Soldier, worker, and alate caste and two larval cDNA libraries were constructed, and approximately 15,000 randomly chosen clones were sequenced to compile an EST data base. Putative gene functions were assigned based on a BLASTX Swissprot search. Categorical in silico expression patterns for each library were compared using the R-statistic. A significant proportion of the ESTs of each caste and life stages had no significant similarity to those in existing data bases. All cDNA libraries, including those of non-reproductive worker and soldier castes, contained sequences with putative reproductive functions. Genes that showed a potential expression bias among castes included a putative antibacterial humoral response and translation elongation protein in soldiers and a chemosensory protein in alates. Conclusions: We have expanded upon the available sequences for R. flavipes and utilized an in silico method to compare gene expression in different castes of an eusocial insect. The in silico analysis allowed us to identify several genes which may be differentially expressed and involved in caste differences. These include a gene overrepresented in the alate cDNA library with a predicted function of neurotransmitter secretion or cholesterol absorption and a gene predicted to be involved in protein biosynthesis and ligase activity that was overrepresented in the late larval stage cDNA library. The EST data base and analyses reported here will be a valuable resource for future studies on the genomics of R. flavipes and other termites. [ABSTRACT FROM AUTHOR]

Tunnel volumes excavated by laboratory groups of the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), and the eastern subterranean termite, Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae) were measured by using two-dimensional foraging arenas. Group sizes of 20, 40, 60, 80, 100, and 200 termites were used for the study. Analysis of the images of tunnels taken hourly showed tunnel volume increased and eventually reached equilibrium for both termite species, but Co. formosanus reached the equilibrium faster at lower volume than R. flavipes. Co. formosanus constructed fewer primary tunnels with less branching than R. flavipes and no additional tunneling activity was observed once the tunnel volume reached equilibrium. R. flavipes, however, continued tunnel excavation even after reaching equilibrium, but the equilibrated volume was maintained by filling unused tunnels with sand excavated from newly dug tunnels. For each termite species, the tunnel volume equilibrium was proportional to the group size. The mean individual tunnel volume (mm³ per termite ± SE) of all group sizes computed over the whole experiment was significantly higher for 1]. flavipes (198.58 ± 1.21) than for Co. formosanus (84.24 ± 0.59). The shape of the growth curves for tunnel volumes indicated the presence of a double feedback system for termite tunneling activity, and we suggest that the positive relationship between nest and population size previously reported for numerous termites species is the result of the self-organized nest-building activity. [ABSTRACT FROM AUTHOR]

In total, 289 termite samples were collected from 45 counties in Indiana during 2002-2004. Approximately 89% of the collection sites were associated with artificial structures, and almost half of the samples were from inside homes. The rest of the samples were from forested areas. Termite samples were identified based on their morphological characteristics, molecular characteristics, or both. Five species from the genus Reticulitermes were identified, and the relative abundance (percentage of the total collections) of these five species was Reticulitermes flavipes (Kollar) (90.0), Reticulitermes virginicus (Banks) (7.6), Reticulitermes arenincola (Goellner) (1.0), Reticulitermes tibialis (Banks) (1.0), and Reticulitermes hageni Banks (0.3). Based on the distribution map, R. flavipes was the dominant and the most widely distributed species in Indiana (44 counties); followed by R. virginicus (13 counties). The three other Reticulitermes species, R. arenincola, R. tibialis, and R. hageni, were encountered in only five counties. R. arenincola is considered a rare species and its distribution has been limited to sand dunes near Lake Michigan. However, in this study, two of the three R. arenincola samples were collected outside of its type location. R. tibialis was found in three counties, whereas R. hageni was only found in Evansville, IN. To complement the morphological identifications, a 389-bp region of the mitochondrial DNA (mtDNA) 16S rRNA gene was amplified and sequenced from all five Reticulitennes species. Based on species-specific polymorphisms exhibited in mtDNA sequences, a polymerase chain reaction-restriction fragment length polymorphism-based diagnostic tool was developed to identify samples lacking of diagnostic morphological characters. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to assess tunneling and soil movement capabilities of Reticulitermes flavipes (Kollar), the most commonly encountered termite in Oklahoma, through a no-choice test. In the tests, field-collected soils made up of different proportions of sand, silt, and clay were used, which were collected from a native tallgrass prairie habitat, and local river sand. The results show that soil texture significantly influences both the rate of tunneling and amount of soil removed from foraging tubes. The study concludes that normal subterranean termite foraging activities have an important, but not yet fully documented effect on nutrient cycling and soil turnover within the native Tallgrass Prairie National Preserve.

A laboratory study was conducted to determine the toxicity of indoxacarb and chlorantraniliprole to Eastern subterranean termites, Reticulitermes flavipes (Kollar) (Isoptera: Rhinot- ermitidae) resulting from topical applications and exposure to treated soil. Soils with varying organic matter (0.57-3.64%) and chemical characteristics were used in termiticide bioassays. Lethal dose resulting from topical application indicated that chiorantraniliprole was two- to 11-fold more toxic than indoxacarb. Lethal concentration assays yielded opposite results where concentrations of indoxacarb in soil that caused either 50 or 90% mortality of R.flavipes workers at 48 and 144 h were two- to six-fold lower than chlorantraniliprole. The bioavailability of indoxacarb and chlorantraniliprole was nega- tively correlated with soil organic matter. Our results suggest that indoxacarb is more bioavailable to termites in soil than chlorantraniliprole based on calculated bioavailability ratios. However, how these laboratory results correlate to actual field application data and termite efficacy is unknown, and more research is needed. These compounds seem to have excellent activity on termites and have potential to provide new modes of action and new chemistry as liquid termiticides. [ABSTRACT FROM AUTHOR]

Termite alates presumably do not mate in their natal nest or during a swarming event. Rather, after flight, females and males lose their wings, pair, and select a nest site, with mating typically taking place in the incipient nest. In this study of Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae), histology and other techniques were used to assess reproductive features of female and male imagos, including unflown alates, flown alates, and the primary pair in incipient and well-established (5-yr-old) colonies. The spermathecae of female flown alates were devoid of spermatozoa, as expected, but the lumen contained a mucus-like substance. Histochemical tests revealed that this substance was intensely stained by periodic acid-Schiff, which is diagnostic for mucopolysaccharides. This is the first study to confirm that termites possess a mucopolysaccharide secretion in the spermathecal lumen. The secretion may serve as a sperm energy source as has been suggested for some other insects. Transmission electron microscopy subsequently revealed the presence of a semiopaque secretory material in the spermathecal lumen and associated ductules of flown and unflown alates as well as queens. Unflown female alates showed the least reproductive development in terms of spermathecal diameter and terminal oocyte size. Unflown male alates similarly possessed less developed reproductive organs than the kings. [ABSTRACT FROM AUTHOR]

We examined the diversity, habitat preferences, and intraspecific variation of Reticulitermes (Isoptera: Rhinotermitidae) populations within Missouri. Approximately 600 subterranean termite colonies were sampled from paired urban and woodland environments plus home infestations throughout the state. Samples were first identified to species using morphological characters and morphometrics. In addition, a portion of ≈428 bp from the 16S rRNA from 365 samples was sequence to confirm morphology-based species identifications and to describe intraspecific genetic variability of Reticulitermes populations in Missouri. Reticulitermes flavipes (Kollar), Reticulitermes virginicus (Banks), Reticulitermes tibialis Banks, and Reticulitermes hageni Banks were found in Missouri. Twenty-one haplotypes of R.flavipes were identified, which represents one of the highest haplotype diversities reported for this species from a single state. Moreover, nine of these 21 haplotypes have not been reported in the United States before this study. Three haplotypes of R. hageni, five haplotypes of R. tibialis, and four haplotypes of R. virginicus were identified. The most abundant haplotypes of R. flavipes and R. hageni occur in woodlands, urban environments, and home infestations, suggesting a probable local origin for most of the subterranean termite infestations occurring in Missouri. [ABSTRACT FROM AUTHOR]

Abstract: Reticulitermes flavipes workers were topically inoculated with ≈10,000 conidia of the entomopathogenic fungus Metarhizium anisopliae. After being kept in groups of 20 individuals for 1–9 d, histopathological examination showed that termites had an individual immune reaction. The nodule formation at the point of entrance of the fungal hyphae was identified as a cellular encapsulation and the different steps in the nodule formation are described. The relative number of hemocytes per termite increased 24h after fungal exposure and remained high in the hemolymph for at least 3 d before decreasing back to pre-exposure levels. The role of an individual immune cellular reaction in social insects is discussed. [Copyright &y& Elsevier]

Abstract: Allatostatins (ASTs), with a C-terminal sequence Tyr/Phe-Xaa-Phe-Gly-Leu/Ile-amide, are multifunctional neuropeptides that were first discovered by their ability to inhibit juvenile hormone (JH) synthesis by the corpora allata (CA) in cockroaches. These A-type ASTs have since been demonstrated to inhibit JH synthesis in crickets, termites and more recently locusts. The gene for the precursor of A-type ASTs has been identified in several species of cockroaches, in crickets and in locusts, but not yet in termites, although 5 AST peptides were isolated from the lower termite Reticulitermes flavipes that are identical to known cockroach ASTs. In this study, primers designed from AST amino acid sequences of cockroaches are used to identify the gene for the preproAST peptides in R. flavipes. In addition, the expression of the gene in brain tissues is demonstrated for egg-laying and non-egg-laying neotenic reproductives. The gene codes for 14 individual peptides and its sequence is closer to that of cockroaches and the cricket than to that of other insect orders in which these peptides do not act as allatostatins. Among the known cockroach AST genes, the termite AST gene is most similar to that of Periplaneta americana, a species belonging to the primitive family Blattidae. [Copyright &y& Elsevier]

Abstract: The allatostatins (ASTs), with a Tyr/Phe-Xaa-Phe-Gly-Leu/Ile-amide C-terminus, are neuropeptides that occur in many orders of insects, but are known to inhibit juvenile hormone (JH) synthesis by corpora allata (CA) only in cockroaches, crickets, and termites. 5 AST peptides with similar sequences to those of 6 species of cockroaches have been isolated and sequenced from extract of brain tissue of the termite Reticulitermes flavipes. The amino acid sequence of a 6th peptide, R. flavipes AST-7, determined by LC–MS/MS following HPLC fractionation of brain extract, is S-P-S-S-G-N-Q-R-L-Y-G-F-G-L-NH2. The 8 terminal amino acids are identical to AST-7 of the cockroach Diploptera punctata. R. flavipes and D. punctata AST-7s inhibited JH synthesis by CA of both species equally and their affinity for antibody against D. punctata AST-7 is similar. Immunoreactivity of termite tissue with this antibody indicates neuro- and myomodulatory activity of the peptide in addition to its demonstrated allatostatic function. The density of AST immunostaining in axons within the CA of R. flavipes and the rate of JH synthesis by similar glands were negatively correlated. This is evidence that when AST is abundant in the glands it is being released in vivo to limit JH production. [Copyright &y& Elsevier]

Abstract  Primer pheromones play key roles in regulating division of labor, which is a fundamental and defining aspect of insect sociality. Primer pheromones are chemical messengers that transmit hormone-like messages among colony members; in recipients, these messages can either induce or suppress phenotypic caste differentiation. Here, we investigated soldier caste-derived chemicals as possible primer pheromones in the lower termite Reticulitermes flavipes, a species for which no primer pheromones have yet been identified. We determined that soldier head extracts (SHE), when provided to totipotent workers along with the insect morphogenetic juvenile hormone (JH), significantly enhanced soldier caste differentiation. When applied alone, however, SHE had no impacts on caste differentiation, survivorship, or any other aspect of worker biology. These findings support a function of soldier chemicals as primer pheromones that enhance the action of the endogenous JH. In accord with previous studies, γ-cadinene and the corresponding aldehyde, γ-cadinenal, were identified by gas chromatography–mass spectrometry and nuclear magnetic resonance analyses as the two most abundant components of R. flavipes SHE. Validative bioassays with commercially available cadinene confirmed activity. Several other terpenes, previously identified in R. flavipes soldiers, also were found to be active. These findings reveal a novel primer pheromone-like function for soldier-derived terpenes in termites and further suggest convergent evolution of terpene functions in enhancing JH-dependent soldier caste differentiation. [ABSTRACT FROM AUTHOR]

A year-long field experiment showed that Reticulitermes flavipes attacked and used single stakes and wooden stake bundles differently in two habitats that varied in alternative forage. In both habitats, the number of termites present in single stakes and stake-bundles increased with stake resource size, and the number of larvae recorded from feeding sites was a close reflection of the number of workers attracted to a given food source. Over 12 mo, more single stakes and stake bundles were heavily attacked and abandoned in the pine woods compared with grassy clearings, Paradoxically, the number of termites present in single stakes and stake bundles was greater in the food-poor habitat (grassy clearings), yet the wood was less consumed compared with the food-rich habitat (pine woods). Use of stake bundles as nests and the slower rate of wood consumption in grassy clearings indicated that termites seemed to value food resources in relative terms, i.e., those termites with abundant alternative food resources consumed quickly and departed, whereas those lacking extra resources ate slowly and settled in. These field results confirm earlier laboratory results that showed that termites modified wood consumption rates dependent on the amount of food available to the colony as a whole. The appearance of mature (physogastric) reproductives (⪢ 1 yr old) in stake bunches in both habitats further indicated that termites track resources and opportunistically shift colony activities and possibly territory boundaries depending on the nature of the resources and other environmental factors. Implications for managing termites with a baiting strategy are discussed. [ABSTRACT FROM AUTHOR]

Pressure from subterranean termites is known to vary geographically across the United States, but there are few quantitative studies concerning the threat of structural infestation for any geographic region. We assessed the number and locations of termite colonies present on 20 infested residential properties in central North Carolina, where subterranean termite pressure is considered to be heavy. This was achieved by using microsatellite markers to determine colony identity of termites collected over 6-14 mo from mud tubes in structures, below-ground monitors, and wood debris in the yard. In total, we identified 188 distinct colonies and determined their breeding structures. Reticulitermes flavipes (Kollar) was by far the most common species, accounting for nearly 90% of all colonies; the remaining colonies belonged to Reticulitermes hageni Banks and Reticulitermes virginicus (Banks). In four cases, there were two colonies infesting a structure simultaneously; in all other cases only a single colony was detected in the structure. Colony densities were high, averaging 62 colonies per ha (25 per acre) with a maximum of 185 colonies per ha (75 colonies per acre). Foraging ranges of R. flavipes and R. hageni colonies were generally small (<30 linear m), and most colonies were headed by a single pair of monogamous reproductives with nearly all the remaining colonies headed by relatively few inbreeding descendants of the original monogamous pair. These results provide the most detailed picture to date of the number, distribution, and colony characteristics of subterranean termite colonies located in and around residential structures. [ABSTRACT FROM AUTHOR]

Abstract: Immunoreactivity to cockroach Diploptera punctata allatostatin-7 (Dippu AST-7) has been demonstrated previously in axons innervating the corpora allata of the termite Reticulitermes flavipes. This peptide and Dippu AST-11 inhibited juvenile hormone (JH) synthesis by corpora allata (CA) of brachypterous neotenic reproductives (secondary reproductives) of termites. The present study shows that R. flavipes CA are also inhibited by Dippu AST-2, AST-5, AST-8, and AST-9 at approximately the same rank order of potency as demonstrated in D. punctata. Another allatostatin from Periplaneta americana (Peram AST-12) also inhibits JH synthesis by R. flavipes CA. Sensitivity to the allatostatins is higher in glands with low rates of JH synthesis than in those with relatively high JH synthetic rates as has been demonstrated in CA from male and female secondary reproductives as well as in those from non-egg-laying and egg-laying females. The identical inhibitory effects of R. flavipes brain extract on CA from both D. punctata and R. flavipes and the isolation and identification of five cockroach allatostatins (Dippu AST-1, AST-2, AST-5, AST-8, and Peram AST-12) from termite brain extract reflect the close relationship between cockroaches and termites. [Copyright &y& Elsevier]

The effect of temperature on [14C] fipronil uptake and transfer from donor (D) to recipient (R) Reticulitevmes flavipes (Kollar) (Isoptera: Rhinotermitidae) workers was evaluated. Test chambers used in the fipronil uptake study were constructed from petri dishes containing autoclaved soil treated with 1 ppm [14C] fipronil (1.14 µCi of total radioactivity per petri dish), distilled water, and R. flavipes workers. Test chambers were held in environmental growth chambers preset at 12, 17, 22, 27, and 32°C. For the fipronil transfer study, donor termites stained with Nile blue-A were exposed to soil treated with 1 ppm [14C] fipronil for 2 h. Donors were then combined with unexposed recipient termite workers at either 1D:5R, 1D:10R, or 1D:20R ratios. Test chambers consisted of a nest and feeding chamber connected by a piece of polyethylene tube and held in growth chambers at 12, 17, 22, 27, and 32°C. Worker termites were sampled over time and the amount of [14C] fipronil present was measured by scintillation counting. Some degree of uptake and transfer occurred at all temperatures and ratios in this study. The highest level of uptake occurred by termites held at 22-32°C, followed decreasingly by 17 and 12°C. Maximum transfer of [14C] fipronil occurred at the higher ratios (1:5 > 1:10 > 1:20) of donors to recipients. Data presented in this study suggest that temperature is one of the key factors affecting the rate of uptake and subsequent horizontal transfer of [14C] fipronil in subterranean termites. [ABSTRACT FROM AUTHOR]

Abstract: Workers of Reticulitermes flavipes were isolated in groups of increasing numbers to determine the in vitro rates of juvenile hormone (JH) synthesis by individual pairs of corpora allata (CA) as other castes differentiated. Only neotenic reproductives developed in groups of 12. Mean JH synthesis rates increased after 5 weeks but only a few individuals had significantly higher rates, about 0.4pmol/pair/h, which occurred at about 3 weeks before neotenics developed. Soldiers and neotenics developed in groups of 50. Mean rates increased to a peak at week 6 after isolation, but only a few individuals had rates approaching 1pmol/pair/h, which occurred at the same time after isolation as the development of pre-soldiers. JH synthesis by CA of pharate pre-soldiers and soldiers was low compared to that of pharate workers and neotenics. CA of pre-soldiers attained a peak mean rate of JH synthesis of 0.9pmol/pair/h at 6 days of age, whereas CA of soldiers attained only a peak mean rate of 0.3pmol/pair/h. These measurements of JH synthesis by individual pairs of CA suggest that the few workers destined to become pre-soldiers have 2.5-fold higher JH synthesis than the few that would develop into neotenic reproductives, and show that a cycle of synthesis accompanies the development of pre-soldiers into soldiers. [Copyright &y& Elsevier]

Fire is an important part of forest ecosystems, as is the insect fauna. Changes in wood brought about by fire may alter the ability of termites to use the wood, interrupting the decay cycle of woody debris. The ability of termites to find, infest, and feed upon wood after it had been charred was evaluated in the laboratory and field. Eastern subterranean termites, Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae), fed on char from burned wood had significantly reduced numbers of protozoa compared to termites fed on pine shavings, but significantly more than starved termites. The ability of termites to find and infest wood was not affected by surface charring. In a laboratory choice test, there were no significant differences in the onset of feeding by termites between charred and non-charred wood boards. Likewise in the field, no differences were observed in the time to initial attack by termites on charred and non-charred wood boards or bolts. Because termites will likely survive fires of low to moderate intensity, in most cases, there should be no disruption of the termite contribution to forest nutrient and carbon cycles. [ABSTRACT FROM AUTHOR]

Abstract: Efficacy of three prototype termite cellulase inhibitors, cellobioimidazole (CBI), fluoromethylcellobiose (FMCB) and fluoromethylglucose (FMG) was investigated using biochemical and feeding assays. Optimal conditions for measuring endoglucanase, exoglucanase and β-glucosidase activities were first determined. The three inhibitors were then tested under optimal conditions against enzyme fractions that represented endogenous (foregut/salivary gland/midgut) and symbiotic (hindgut) cellulases. In vitro, CBI and FMCB both inhibited exoglucanase and β-glucosidase activity (I50s in nM and mM range, respectively). Feeding assays showed significant impacts on both survivorship and feeding stimulation by FMCB and CBI. Enzymatic measurements on feeding assay survivors showed impacts on all three cellulase activities by CBI and lesser impacts by FMG and FMCB. Validative bioassays with the sugars glucose, maltose and cellobiose showed no feeding stimulation or mortality as occurred in feeding inhibitor bioassays. These results indicate efficacy for two cellobiose-based inhibitors, FMCB and CBI, suggesting potential for these inhibitors as novel termite control agents. [Copyright &y& Elsevier]

Recent changes in termite management technologies have stimulated a need for better understanding of basic termite ecology. Studies estimating the number of individuals in foraging populations and foraging territory sizes of subterranean termite colonies have been conducted in many areas of the United States. However, colonies of Reticulitermes occurring in the central Great Plains have not been well characterized. Results of studies conducted with three colonies of R. flavipes (Kollar) on an Oklahoma native tallgrass prairie are provided herein. Foraging population numbers, foraging areas, maximum linear foraging distances and soldier caste ratios were determined. Estimated foraging areas for individual colonies ranged from 9.0 to 92.3 m². Colonies contained 10,357 to 183,495 foragers. Soldiers comprised 2.69 to 4.46% of the foraging populations. We conclude that rather than the result of a few large populations, the widespread termite pressure in this native habitat is likely the result of many small colonies foraging in close proximity. [ABSTRACT FROM AUTHOR]