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Termites play a major role in a variety of ecological processes in tropical and subtropical biomes worldwide, such as decomposition, soil formation and aeration, and nutrient cycling. These important ecosystem services were achieved through their highly complex societies and remarkable adaptations, including the evolution of reproductive division of labour, the acquisition of endosymbionts and the capacity for extensive environmental engineering, yet the causes and consequences of their ecological success are still poorly understood. The goals of our study were (a) to provide the first complete, species-level phylogeny of all currently recognized termite species by integrating the available genetic and taxonomic data, as well as methods of phylogenetic imputation and divergence time estimation; and (b) to explore variation in speciation rates among termite lineages. We provide the inferred relationships as a set of 1,000 pseudo-posterior trees, which can be used in future comparative analyses. We demonstrate that speciation rates have been relatively constant throughout the history of termites, with two positive shifts in speciation rates: one at their origin of Euisoptera and the other concordant with evolution of Termitidae. On the other hand, there was no obvious trend towards deceleration in speciation rates for termites as a whole, nor within the most species-rich families. The provided trees might represent a valuable resource for termite comparative studies by summarizing the available phylogenetic information, while accounting for uncertainty in the inferred topologies.

Termites play a major role in a variety of ecological processes in tropical and subtropical biomes worldwide, such as decomposition, soil formation and aeration, and nutrient cycling. These important ecosystem services were achieved through their highly complex societies and remarkable adaptations, including the evolution of reproductive division of labour, the acquisition of endosymbionts and the capacity for extensive environmental engineering, yet the causes and consequences of their ecological success are still poorly understood. The goals of our study were (a) to provide the first complete, species-level phylogeny of all currently recognized termite species by integrating the available genetic and taxonomic data, as well as methods of phylogenetic imputation and divergence time estimation; and (b) to explore variation in speciation rates among termite lineages. We provide the inferred relationships as a set of 1,000 pseudo-posterior trees, which can be used in future comparative analyses. We demonstrate that speciation rates have been relatively constant throughout the history of termites, with two positive shifts in speciation rates: one at their origin of Euisoptera and the other concordant with evolution of Termitidae. On the other hand, there was no obvious trend towards deceleration in speciation rates for termites as a whole, nor within the most species-rich families. The provided trees might represent a valuable resource for termite comparative studies by summarizing the available phylogenetic information, while accounting for uncertainty in the inferred topologies.

Termites are eusocial insects having evolved several feeding, nesting and reproductive strategies. Among them, inquiline termites live in a nest built by other termite species: some of them do not forage outside the nest, but feed on food stored by the host or on the nest material itself. In this study, we characterized some dimensions of the ecological niche of Cavitermes tuberosus (Termitidae: Termitinae), a broad-spectrum inquiline termite with a large neotropical distribution, to explain its ecological success. We used an integrative framework combining ecological measures (physico-chemical parameters, stable isotopic ratios of N and C) and Illumina MiSeq sequencing of 16S rRNA gene to identify bacterial communities and to analyse termites as well as the material from nests constructed by different termite hosts (the builders). Our results show that (1) nests inhabited by C. tuberosus display a different physico-chemical composition when compared to nests inhabited by its builder alone; (2) stable isotopic ratios suggest that C. tuberosus feeds on already processed, more humified, nest organic matter; and (3) the gut microbiomes cluster by termite species, with the one of C. tuberosus being much more diverse and highly similar to the one of its main host, Labiotermes labralis. These results support the hypothesis that C. tuberosus is a generalist nest feeder adapted to colonize nests built by various builders, and explain its ecological success., SCOPUS: ar.j, info:eu-repo/semantics/published

Palm plantations are of great socio-economic and ecological importance in Tunisia. They currently contain some three million trees that produce significant supplies of wood for the craft and furniture industries. In the past, date palm wood was also used as structural mate-rial. Its poor technological properties were improved by immersing in natural saltwater the freshly felled palm tree trunks. This was an ancestral practice in the Maghreb area, but it has now disappeared and information on the different parameters involved in this kind of process is scarce. The aim of this study was to assess the main technological properties of Phoenix dactylifera L. wood when preserved by salting. Wood samples collected in southern Tunisia from two common date palm cultivars (Kentichi and Deglet Noor) ranging from 40 to 50 years in age, untreated and preserved by salting in the Chot Djérid lake, were used for the experiments. The densities, mechanical properties, resistance to fungus and termites and chemical compositions of the untreated (control) and saltwater-treated palm wood samples were determined. The results showed a significant increase in the air-dried density of palm wood after immersion in saltwater. Saltwater treatment also greatly improved the Modulus of Rupture of palm wood perpendicular and parallel to the fibres. Both untreated and saltwater-treated palm wood appeared to be sensitive to termite attacks, but the treated palm wood seemed to be more toxic to the termites. Extractives, lignin and cellulose contents were slightly more abundant in the control samples, while hemicelluloses were more abundant in the treated samples. The analyses of mineral composition also provided some explanation of the improvement in palm wood performance after this natural preservation process.

Palm plantations are of great socio-economic and ecological importance in Tunisia. They currently contain some three million trees that produce significant supplies of wood for the craft and furniture industries. In the past, date palm wood was also used as structural mate-rial. Its poor technological properties were improved by immersing in natural saltwater the freshly felled palm tree trunks. This was an ancestral practice in the Maghreb area, but it has now disappeared and information on the different parameters involved in this kind of process is scarce. The aim of this study was to assess the main technological properties of Phoenix dactylifera L. wood when preserved by salting. Wood samples collected in southern Tunisia from two common date palm cultivars (Kentichi and Deglet Noor) ranging from 40 to 50 years in age, untreated and preserved by salting in the Chot Djérid lake, were used for the experiments. The densities, mechanical properties, resistance to fungus and termites and chemical compositions of the untreated (control) and saltwater-treated palm wood samples were determined. The results showed a significant increase in the air-dried density of palm wood after immersion in saltwater. Saltwater treatment also greatly improved the Modulus of Rupture of palm wood perpendicular and parallel to the fibres. Both untreated and saltwater-treated palm wood appeared to be sensitive to termite attacks, but the treated palm wood seemed to be more toxic to the termites. Extractives, lignin and cellulose contents were slightly more abundant in the control samples, while hemicelluloses were more abundant in the treated samples. The analyses of mineral composition also provided some explanation of the improvement in palm wood performance after this natural preservation process.

Thermal modification is an attractive alternative to improve the decay durability and dimensional stability of wood. However, thermally modified wood is generally not resistant to termite attacks, limiting the field of application of such materials. One way to overcome this drawback is to combine thermal modification treatment with an additional treatment. One such treatment is the impregnation of a boron derivative associated with appropriate vinylic monomers, which takes advantage of the thermal treatment to polymerise these monomers for boron fixation. Using this strategy, we recently showed that an impregnation of borax (2 or 4% boric acid equivalent) dissolved in a 10% aqueous solution of polyglycerolmethacrylate followed by thermal treatment under nitrogen at 220°C protects wood from both termite and decay degradations, even after leaching. Additionally, wood samples treated with a 10% polyglycerolmethacrylate aqueous solution and subjected to thermal treatment at 220°C presented improved resistance to termites while avoiding boron utilization. Based on these results, we investigate the effect of impregnation with two types of vinylic monomers, which are already used in the presence of boron, followed by thermal treatments at different temperatures. We evaluate termite and decay durability of wood to evaluate if thermal modification associated with light chemical modification could be a solution for utilization of thermally modified materials in termite-infested areas.

Thermal modification is an attractive alternative to improve the decay durability and dimensional stability of wood. However, thermally modified wood is generally not resistant to termite attacks, limiting the field of application of such materials. One way to overcome this drawback is to combine thermal modification treatment with an additional treatment. One such treatment is the impregnation of a boron derivative associated with appropriate vinylic monomers, which takes advantage of the thermal treatment to polymerise these monomers for boron fixation. Using this strategy, we recently showed that an impregnation of borax (2 or 4% boric acid equivalent) dissolved in a 10% aqueous solution of polyglycerolmethacrylate followed by thermal treatment under nitrogen at 220°C protects wood from both termite and decay degradations, even after leaching. Additionally, wood samples treated with a 10% polyglycerolmethacrylate aqueous solution and subjected to thermal treatment at 220°C presented improved resistance to termites while avoiding boron utilization. Based on these results, we investigate the effect of impregnation with two types of vinylic monomers, which are already used in the presence of boron, followed by thermal treatments at different temperatures. We evaluate termite and decay durability of wood to evaluate if thermal modification associated with light chemical modification could be a solution for utilization of thermally modified materials in termite-infested areas.

Termites are major decomposers in tropical regions and play critical roles in many soil-related processes. Studies conducted in Asia and the Neotropics suggest that habitat modification can strongly affect termite assemblages, but data on termite communities from forests in Africa, especially West Africa, are scarce. Here, we measured the short-term impact of slash-and-burn agriculture on termite assemblages in an agricultural region of central Côte d'Ivoire. We assessed termite diversity and relative abundance in four habitat types: secondary forest, cleared forest, burned forest, and crop fields. The secondary forest had higher species richness compared with the other habitats, but all habitat types had similar assemblage structures. Fungus-growing termites were the most abundant feeding group in all habitats. Soil feeders were most abundant in secondary forest, intermediately abundant in cleared and burned forests, and almost entirely absent in crop fields. Wood-feeding species showed clear responses to burning; their abundances decreased after fire. We conclude that slash-and-burn agriculture does not appear to severely erode the diversity of termite assemblages. This could be due to the dominance of ecologically versatile fungus growers or to the relatively long time between clearing and burning. However, forest clearing negatively affects soil feeders, with the Apicotermitinae most affected by canopy loss., SCOPUS: ar.j, info:eu-repo/semantics/published

Termite colonies are typically founded by a pair of sexually reproducing dispersers, which can sometimes be replaced by some of their offspring. Some Reticulitermes and Embiratermes species routinely practice asexual queen succession (AQS): the queen is replaced by neotenic daughters produced by parthenogenesis, which mate with the primary king. Here, to cast light on the evolution of AQS, we investigated another candidate species, Cavitermes tuberosus (Termitinae). Of 95 nests, 39 contained a primary queen and 28 contained neotenic females (2–667 individuals), usually with the primary king. Microsatellite analyses confirmed that colonies were initiated by single pairs after large dispersal flights. More than 80% of the neotenic females were of exclusively maternal origin and completely homozygous, suggesting automictic parthenogenesis with gamete duplication. Conversely, workers, soldiers, and most alates and primary reproductives were produced sexually. AQS often occurs late, after colonies have reached maturity, whereas early AQS in other species may boost the young colony’s growth rate. We suggest additional benefits of AQS in C. tuberosus, related with a smaller size, lesser stability and higher mobility of colonies. Our data add to the phylogenetical dispersion and diversity of modalities of AQS in termites, supporting a multiple evolutionary origin of this process., SCOPUS: ar.j, info:eu-repo/semantics/published

Asexual queen succession (AQS), in which workers, soldiers and dispersing reproductives are produced sexually while numerous non-dispersing queens arise through thelytokous parthenogenesis, has recently been described in three species of lower termites of the genus Reticulitermes. Here, we show that AQS is not an oddity restricted to a single genus of lower termites, but a more widespread strategy occurring also in the most advanced termite group, the higher termites (Termitidae). We analysed the genetic structure in 10 colonies of the Neotropical higher termite Embiratermes neotenicus (Syntermitinae) using five newly developed polymorphic microsatellite loci. The colonies contained one primary king accompanied either by a single primary queen or by up to almost 200 neotenic queens. While the workers, the soldiers and most future dispersing reproductives were produced sexually, the nondispersing neotenic queens originated through thelytokous parthenogenesis of the founding primary queen. Surprisingly, the mode of thelytoky observed in E. neotenicus is most probably automixis with central fusion, contrasting with the automixis with terminal fusion documented in Reticulitermes. The occurrence of AQS based on different mechanisms of ploidy restoration raises the hypothesis of an independent evolutionary origin of this unique reproductive strategy in individual lineages of lower and higher termites., SCOPUS: ar.j, info:eu-repo/semantics/published

Asexual queen succession (AQS), in which workers, soldiers and dispersing reproductives are produced sexually while numerous non-dispersing queens arise through thelytokous parthenogenesis, has recently been described in three species of lower termites of the genus Reticulitermes. Here, we show that AQS is not an oddity restricted to a single genus of lower termites, but a more widespread strategy occurring also in the most advanced termite group, the higher termites (Termitidae). We analysed the genetic structure in 10 colonies of the Neotropical higher termite Embiratermes neotenicus (Syntermitinae) using five newly developed polymorphic microsatellite loci. The colonies contained one primary king accompanied either by a single primary queen or by up to almost 200 neotenic queens. While the workers, the soldiers and most future dispersing reproductives were produced sexually, the nondispersing neotenic queens originated through thelytokous parthenogenesis of the founding primary queen. Surprisingly, the mode of thelytoky observed in E. neotenicus is most probably automixis with central fusion, contrasting with the automixis with terminal fusion documented in Reticulitermes. The occurrence of AQS based on different mechanisms of ploidy restoration raises the hypothesis of an independent evolutionary origin of this unique reproductive strategy in individual lineages of lower and higher termites., SCOPUS: ar.j, info:eu-repo/semantics/published

Trials referring applicability of the final product, such as durability tests to fungi and termites are crucial in developing panels. Therefore, panels made with different percentages of sugarcane bagasse particles (Saccharum sp.) and eucalyptus fiber (Eucalyptus grandis), bounded with two dosages of urea formaldehyde resin (13% and 16%), were evaluated for biological resistance (bioassays) to termites and fungi, which is fundamental in defining use and application of the final product. We used the termite species Reticulitermes santonensis, rhinotermitidade, and the fungy Pleurotus ostreatus, a white rot basidiomycete, according to AFNOR standardization procedures. In general, the new panels were not resistant to bioassays and there was a similarity in the dynamics of attack and mass loss among the different doses of resin applied, thus evidencing the need of applying protective coating on the panels surface or adding termiticide and fungicide products.

Trials referring applicability of the final product, such as durability tests to fungi and termites are crucial in developing panels. Therefore, panels made with different percentages of sugarcane bagasse particles (Saccharum sp.) and eucalyptus fiber (Eucalyptus grandis), bounded with two dosages of urea formaldehyde resin (13% and 16%), were evaluated for biological resistance (bioassays) to termites and fungi, which is fundamental in defining use and application of the final product. We used the termite species Reticulitermes santonensis, rhinotermitidade, and the fungy Pleurotus ostreatus, a white rot basidiomycete, according to AFNOR standardization procedures. In general, the new panels were not resistant to bioassays and there was a similarity in the dynamics of attack and mass loss among the different doses of resin applied, thus evidencing the need of applying protective coating on the panels surface or adding termiticide and fungicide products.

This article provides a meta-analysis of quantitative data available in literature regarding the relation between termite numbers and the volume of their mounds for 24 species belonging to 13 genera. The leading question behind this analysis is: "how do the respiratory gas exchanges regulate the size of termite mounds?" This question is answered through the analysis of the log-log regression between the volume of the mound and the number of inhabitants. The most confident data support the hypothesis of a respiratory regulation that can be achieved through a relation between the termite numbers and (1) the volume of their mounds (slope of the regression near 1, Noditermes), (2) the surface of the outer walls of their mounds (slope of the regression near 0.67, Termitinae and Nasutitermes) or (3) a compromise between the surface of the outer walls of their mounds and some linear structures of their nests (slope of the regression between 0.67 and 0.33, Trinervitermes and Macrotermes). The way this is achieved is linked with the architecture of the mound. A confident relation was found between the number of individuals and the epigeal volume of their mounds for 18 species for which the most reliable data were provided. Three more accurate models are proposed for estimating the termite population based on the nest material and architecture and on the size of the termites. © International Union for the Study of Social Insects (IUSSI) 2010., SCOPUS: ar.j, info:eu-repo/semantics/published

This article provides a meta-analysis of quantitative data available in literature regarding the relation between termite numbers and the volume of their mounds for 24 species belonging to 13 genera. The leading question behind this analysis is: "how do the respiratory gas exchanges regulate the size of termite mounds?" This question is answered through the analysis of the log-log regression between the volume of the mound and the number of inhabitants. The most confident data support the hypothesis of a respiratory regulation that can be achieved through a relation between the termite numbers and (1) the volume of their mounds (slope of the regression near 1, Noditermes), (2) the surface of the outer walls of their mounds (slope of the regression near 0.67, Termitinae and Nasutitermes) or (3) a compromise between the surface of the outer walls of their mounds and some linear structures of their nests (slope of the regression between 0.67 and 0.33, Trinervitermes and Macrotermes). The way this is achieved is linked with the architecture of the mound. A confident relation was found between the number of individuals and the epigeal volume of their mounds for 18 species for which the most reliable data were provided. Three more accurate models are proposed for estimating the termite population based on the nest material and architecture and on the size of the termites. © International Union for the Study of Social Insects (IUSSI) 2010., SCOPUS: ar.j, info:eu-repo/semantics/published

Termites represent one of the most abundant belowground animal taxa in tropical rainforests, where their species richness is much higher than in any other ecosystem. This high diversity in soil ecosystems is however difficult to explain by classical Hutchinsonian niche theory, as there is little evidence for spatial or temporal separation between species. Using δ13C and δ15N isotopic ratios, we tested if resource partitioning along the humification gradient occurs in neotropical soldierless termites of the Anoplotermes-group. Two distinct sites were investigated to check if interspecific differences are transposable between sites. Significant differences in δ15N were found between species of the Anoplotermes-group. Although some species displayed higher intersite δ15N variation than others, species-average δ15N values for both sites were highly correlated, showing that sympatric soldierless soil-feeding termites feed on distinct components of the soil. Our data also suggest that some species are more likely to shift along this gradient than others, in response to overall habitat conditions or to the presence of competitors. Feeding niche differentiation can therefore account for the high species richness and diversity of soldierless soil-feeding termites in neotropical rainforests. © 2009 Elsevier Ltd. All rights reserved., SCOPUS: ar.j, info:eu-repo/semantics/published

Depuis une vingtaine d'années, la présence des termites dans tes habitations n'a cessé de s'accroître. Plus de 60 départements sont actuellement Infestés. Les dégâts causés sont importants car les termites se nourrissent essentiellement de cellulose. Cependant, grâce à une meilleure connaissance du phénomène, la lutte s'organise en associant tes scientifiques, les industriels, les applicateurs et les administrations. De nouvelles techniques permettent de mieux se protéger et de combattre ce fléau.

Depuis une vingtaine d'années, la présence des termites dans tes habitations n'a cessé de s'accroître. Plus de 60 départements sont actuellement Infestés. Les dégâts causés sont importants car les termites se nourrissent essentiellement de cellulose. Cependant, grâce à une meilleure connaissance du phénomène, la lutte s'organise en associant tes scientifiques, les industriels, les applicateurs et les administrations. De nouvelles techniques permettent de mieux se protéger et de combattre ce fléau.

Les Mofu du Nord-Cameroun vivent, ou plutôt vivaient, avec les insectes. Ces derniers sont impliqués dans tous les aspects de leur vie : ils entrent dans l'alimentation et la pharmacopée, viennent en appui agronomique, servent d'augures et même d'insectes de compagnie. Les Mofu, céréaliculteurs de montagne, ont valorisé le mil au point d'en faire l'objet d'une véritable religion. Ils opposent un registre d'insectes bénéfiques pour le mil à ceux qui sont maléfiques et aux ravageurs. Les premiers aident le mil, des semailles au battage et jusque dans les silos. La lutte contre les seconds passe plus par des pratiques rituelles que par l'application de recettes phytosanitaires traditionnelles. L'assainissement des habitations à l'aide d'un Dorylus dénote une connaissance précise de l'éthologie des insectes. Ce même Dorylus livre, sinon la clé d'une grille classificatoire anthropisée du monde des insectes, du moins illustre-t-il une volonté d'y projeter la structure et les comportements de la société mofu. Aujourd'hui, les Mofu descendent sur les piémonts et vont travailler dans les villes, ainsi perdent-ils progressivement l'intimité qu'ils entretenaient avec leurs insectes.

SCOPUS: ar.j, info:eu-repo/semantics/published

Les Mofu du Nord-Cameroun vivent, ou plutôt vivaient, avec les insectes. Ces derniers sont impliqués dans tous les aspects de leur vie : ils entrent dans l'alimentation et la pharmacopée, viennent en appui agronomique, servent d'augures et même d'insectes de compagnie. Les Mofu, céréaliculteurs de montagne, ont valorisé le mil au point d'en faire l'objet d'une véritable religion. Ils opposent un registre d'insectes bénéfiques pour le mil à ceux qui sont maléfiques et aux ravageurs. Les premiers aident le mil, des semailles au battage et jusque dans les silos. La lutte contre les seconds passe plus par des pratiques rituelles que par l'application de recettes phytosanitaires traditionnelles. L'assainissement des habitations à l'aide d'un Dorylus dénote une connaissance précise de l'éthologie des insectes. Ce même Dorylus livre, sinon la clé d'une grille classificatoire anthropisée du monde des insectes, du moins illustre-t-il une volonté d'y projeter la structure et les comportements de la société mofu. Aujourd'hui, les Mofu descendent sur les piémonts et vont travailler dans les villes, ainsi perdent-ils progressivement l'intimité qu'ils entretenaient avec leurs insectes.

SCOPUS: ar.j, info:eu-repo/semantics/published

Au Burkina Faso, la dégradation biologique des bois pose de gros problèmes; les termites, en particulier, provoquent beaucoup de dégâts. Dans la recherche d'une alternative au traitement chimique, nous avons mesuré expérimentalement la durabilité conférée au bois de hêtre par la torréfaction

Au Burkina Faso, la dégradation biologique des bois pose de gros problèmes; les termites, en particulier, provoquent beaucoup de dégâts. Dans la recherche d'une alternative au traitement chimique, nous avons mesuré expérimentalement la durabilité conférée au bois de hêtre par la torréfaction

SCOPUS: ar.j, info:eu-repo/semantics/published

SCOPUS: ar.j, info:eu-repo/semantics/published

Cette note a pour objet de présenter un appareil conçu et mis au point au CTFT, permettant, d'une part, de pallier les inconvénients de la méthode traditionnelle et conduisant, d'autre part, à une meilleure fiabilité dans le comptage et à une plus grande rapidité d'exécution

Cette note a pour objet de présenter un appareil conçu et mis au point au CTFT, permettant, d'une part, de pallier les inconvénients de la méthode traditionnelle et conduisant, d'autre part, à une meilleure fiabilité dans le comptage et à une plus grande rapidité d'exécution

info:eu-repo/semantics/published

FLWNA, info:eu-repo/semantics/published

FLWNA, info:eu-repo/semantics/published