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Porth, I., Scotti-Saintagne, C., Barreneche, T., Kremer, A., & Burg, K. (2005). Linkage mapping of osmotic stress induced genes of oak. Tree Genet. Genomes, 1(1), 31–40.
Abstract: Water stress affecting long-lived trees is an important challenge in forestry. Due to global climate change, forest trees will be threatened by extreme conditions like flooding or drought. It is necessary to understand differences in stress tolerance within certain species and to investigate putative relations on genomic level. In this study, osmotic stress induced genes of Quercus ssp. were positioned on two genetic linkage maps of oak. An intra-specific cross 3P*A4 of Quercus robur consisting of 88 offspring and an inter-specific cross 11P*QS29 of Q. robur and Q. petraea comprising 72 full-sibs were analyzed for the inheritance of 14 loci represented by 34 individual single nucleotide polymorphisms. Seven genes in the intra-cross, as well as other six genes in the inter-cross could be mapped and one gene could not be localised due to the severe distortion of the segregation. The collection of expressed sequences involved ribosomal proteins, members of the oxylase/oxygenase gene family, betaine aldehyde dehydrogenase, Dc3 promoter-binding factor, a putative member of the nodulin family, glutathione-S-transferase and proteins with unknown functions. In the inter-cross, two linked markers exhibited 89% deficiency of heterozygosity. Thirteen genes were positioned on ten different oak chromosomes and can serve as orthologous markers in comparative mapping studies within Fagaceae. © Springer-Verlag 2005.
Keywords: Est; Linkage map; Oak; Osmotic stress; Quercus ssp.; Fagaceae; Quercus; Quercus petraea; Quercus robur
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Latouche-Hallé, C., Ramboer, A., Bandou, E., Caron, H., & Kremer, A. (2003). Nuclear and chloroplast genetic structure indicate fine-scale spatial dynamics in a neotropical tree population. Heredity, 91(2), 181–190.
Abstract: Dicorynia guianensis is a canopy tree, endemic to the tropical rain forest of French Guiana. We compared generational and spatial genetic structure for maternally and biparentally inherited markers in two cohorts (adult and seedling) in order to infer processes shaping the distribution of genetic diversity. The study was conducted on a 40 ha study plot located at Paracou near Kourou, where 172 adults trees and 375 saplings were sampled. Aggregation of trees was therefore suggested at different distances, ranging from 100 to 400 m. There was a strong link between demographic and genetic spatial structures at small distances (less than 100 m) that is likely to be the consequence of restricted seed dispersal. Genetic differentiation was more pronounced between spatial aggregates than between cohorts. Despite the spatial differentiation, the species was able to maintain high levels of diversity for maternal genomes, suggesting rapid turnover of aggregates. Spatial autocorrelation was larger for chloroplast than nuclear markers indicating a strong asymmetry between pollen and seed flow. Fixation indices indicated a lower heterozygote deficiency for the adults, maybe because of gradual elimination of selfed trees. Genetic relatedness at lower distances was higher in adult trees than in saplings, as a result of generation overlapping in the adult cohort. Overall, our results confirm earlier biological knowledge about the dispersion mechanisms of the species, and lead to an enhanced role of spatial processes in the dynamics of genetic diversity of D. guianensis.
Keywords: Dicorynia guianensis; Gene flow; Genetic differentiation; Microsatellites; Spatial analysis; Tropical tree; gene flow; genetic structure; population genetics; spatial analysis; tree; tropical forest; Cell Nucleus; Chloroplasts; Cohort Studies; DNA, Plant; French Guiana; Genetic Markers; Pollen; Population Dynamics; Seeds; Trees; Variation (Genetics); French Guiana; Dicorynia guianensis; Embryophyta
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Groc, S., Delabie, J. H. C., Cereghino, R., Orivel, J., Jaladeau, F., Grangier, J., et al. (2007). Ant species diversity in the 'Grands Causses' (Aveyron, France): In search of sampling methods adapted to temperate climates RID C-4034-2011. C. R. Biol., 330(12), 913–922.
Abstract: This study aimed at showing the applicability of using a combination of four sampling methods (i.e., Winkler extractors, pitfall traps, baiting and manual collection), something most often conducted in the tropics, to create an inventory of ant species diversity in temperate environments. We recorded a total of 33 ant species in the Grands Causses by comparing three vegetal formations: a steppic lawn ('causse' sensu stricto), which was the most species-rich (29 species), followed by an oak grove (22 species) and a pine forest (17 species). No sampling method alone is efficient enough to provide an adequate sampling, but their combination permits one to make a suitable inventory of the myrmecofauna and to obtain information on the ecology of these ant species.
Keywords: ant diversity; Grands Causses; sampling methods; temperate climate
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Sharma, K., Degen, B., Von Wuehlisch, G., & Singh, N. B. (2002). Allozyme variation in eight natural populations of Pinus roxburghii Sarg. in India. Silvae Genet., 51(5-6), 246–253.
Abstract: Seeds collected from eight populations of Chir pine (Pinus roxburghii SARG.) from the natural distribution range of the species in Himachal Himalayas in India were analysed isozymatically at 11 enzyme systems. For the enzyme systems studied, 25 gene loci were identified out of which 18 were polymorphic. The observed mean values for genetic variation were slightly lower than mean values reported for Pinus species (number of alleles: 1.65 compared to 2.36; effective number of alleles: 1.13 compared to 1.26; observed heterozygosity: 0.153 compared to 0.179). A small differentiation among populations and large variation within populations were reflected by small value of GST (0.04): Considering the different genetic parameters three populations seem favourable for gene conservation measures.
Keywords: Allozymes; Differentiation; Genetic distance; Multilocus diversity; Pinus roxburghii; Variation; Enzymes; Forestry; Genes; Allozyme variations; Genetic engineering; Enzymes; Genes; Genetic Engineering; Pinus Roxburghii; Embryophyta; Pinus roxburghii
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Zhang, T., Bai, S. - L., Bardet, S., Almeras, T., Thibaut, B., & Beauchene, J. (2011). Radial variations of vibrational properties of three tropical woods. J. Wood Sci., 57(5), 377–386.
Abstract: The radial trends of vibrational properties, represented by the specific dynamic modulus (E′/ρ) and damping coefficient (tan δ), were investigated for three tropical rainforest hardwood species (Simarouba amara, Carapa procera, and Symphonia globulifera) using free-free flexural vibration tests. The microfibril angle (MFA) was estimated using X-ray diffraction. Consistent patterns of radial variations were observed for all studied properties. E′/ρ was found to decrease from pith to bark, which was strongly related to the increasing pith-bark trend of MFA. The variation of tan δ along the radius could be partly explained by MFA and partly by the gradient of extractives due to heartwood formation. The coupling effect of MFA and extractives could be separated through analysis of the log(tan δ) versus log(E′/ρ) diagram. For the species studied, the extractive content putatively associated with heartwood formation generally tends to decrease the wood damping coefficient. However, this weakening effect of extractives was not observed for the inner part of the heartwood, suggesting that the mechanical action of extractives was reduced during their chemical ageing. © 2011 The Japan Wood Research Society.
Keywords: Damping coefficient; Dynamic modulus; Extractives; Microfibril angle; Tropical woods
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Delabie, J. H. C., Groc, S., & Dejean, A. (2011). The tramp ant technomyrmex vitiensis (Hymenoptera: Formicidae: Dolichoderinae) on South America. Fla. Entomol., 94(3), 688–689.
Abstract: Technomyrmex vitiensis is a tramp ant that has spread through many parts of the Old World tropics via human commerce. This species has been previously reported only once in the New World, from San Francisco, California. Here, we report the first records of T. vitiensis in South America, from two sites deep in the forest of French Guiana. It is not clear how these ants were transported to such remote sites, 100 km inland. Copyright © 2011 BioOne All rights reserved.
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Faucheux, M. J., & Gibernau, M. (2011). Antennal sensilla in five Psychodini moth flies (Diptera: Psychodidae: Psychodinae) pollinators of Arum spp. (Araceae). Ann. Soc. Entomol. Fr., 47(1-2), 89–100.
Abstract: The pollination of the genus Arum (Araceae) is mainly achieved by deception, the floral odour mimicking the pollinator ovipositing site. In order to discover the sensory organs involved in this attraction, we have studied the antennae of five species of psychodine moth-flies (former Psychoda sensu lato = Psychodini), pollinators of Arum spp. The antennae of the five Psychodini reveal seven types of sensilla: multiporous tribranched sensilla basiconica (sensilla ascoidea), multiporous sensilla basiconica, multiporous sensilla coeloconica, multiporous sensilla auricillica, uniporous sensilla basiconica, aporous sensilla chaetica, aporous Böhm's sensilla. Each species possesses three, five or six of these sensillum types. All the multiporous sensilla are probably olfactory receptors while the uniporous sensilla basiconica must possess a contact chemoreceptive function. The multiporous tribranched sensilla basiconica (s. ascoidea), present in all the species, are the best candidates for the reception of the odours given off by the ovipositing sites and the inflorescences of Arum. The multiporous sensilla basiconica and the multiporous sensilla coeloconica may be involved respectively as CO2 receptors or thermoreceptors. Psychoda phalaenoides, which is the main pollinator of A. maculatum, is the species which possesses the largest number of antennal sensilla. The sexual dimorphism, studied only in Psycha grisescens, as concerns the number of sensilla and the absence of a sensillum type which differ according to sex, is difficult to interpret.
Keywords: Chodopsycha; Deceptive pollination; Logima; Psycha; Psychoda
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Chartier, M., Pélozuelo, L., & Gibernau, M. (2011). Do floral odor profiles geographically vary with the degree of specificity for pollinators? Investigation in two sapromyophilous Arum species (Araceae). Ann. Soc. Entomol. Fr., 47(1-2), 71–77.
Abstract: We compared floral odour profiles among populations of two Arum species which show different degrees of specificity for their fly pollinators. Insects were collected from inflorescences in four populations of Arum italicum and two populations of Arum maculatum. In six Arum populations, we compared inflorescences odour profiles collected by Solid Phase Micro Extraction (SPME) and analysed by gas chromatography. We confirmed that from a pollination point of view, A. italicum is an opportunist species, as it is mainly pollinated by insects of the families Psychodidae, Chironomidae and Sciaridae, whereas A. maculatum is a specialist species, as it is 90% pollinated by Psychodidae. In all populations, Arum italicum was less attractive to pollinators than Arum maculatum. Floral odour profiles of A. italicum were not geographically structured among populations, suggesting a high gene flow or adaptation to a fluctuant guild of pollinators. On the contrary, odour profiles of A. maculatum varied between the two populations studied suggesting a lower gene flow or adaptation to different local pollinator preferences.
Keywords: Arum italicum; Arum maculatum; Floral scent; Psychodidae; Specificity
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Mariano, C. S. F., Silva Santos, I. D. A., Groc, S., Leroy, C., Malé, P. - J., Ruiz-González, M. X., et al. (2011). The karyotypes of Gigantiops destructor (Fabricius) and other ants from French Guiana (Formicidae). Ann. Soc. Entomol. Fr., 47(1-2), 140–146.
Abstract: The aim of this study, which was conducted in French Guiana, was to characterize the karyotypes of nine ant species belonging to the genera Anochetus, Apterostigma, Cyphomyrmex, Camponotus, Gigantiops, Myrmicocrypta, Odontomachus and Pseudomyrmex, and to compare them with published data. We present the first descriptions of the karyotypes of Gigantiops destructor (Fabricius), an endemic Formicinae of the Amazonian region, which is the only living species in the tribe Gigantiopini, and of a species from the poorly-known cryptic genus Myrmicocrypta, which belongs to the Myrmicinae tribe Attini.
Keywords: Chromosome number; Diversity; Minimum interaction theory
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Bremaud, I., Gril, J., & Thibaut, B. (2011). Anisotropy of wood vibrational properties: dependence on grain angle and review of literature data. Wood Sci. Technol., 45(4), 735–754.
Abstract: The anisotropy of vibrational properties influences the acoustic behaviour of wooden pieces and their dependence on grain angle (GA). As most pieces of wood include some GA, either for technological reasons or due to grain deviations inside trunks, predicting its repercussions would be useful. This paper aims at evaluating the variability in the anisotropy of wood vibrational properties and analysing resulting trends as a function of orientation. GA dependence is described by a model based on transformation formulas applied to complex compliances, and literature data on anisotropic vibrational properties are reviewed. Ranges of variability, as well as representative sets of viscoelastic anisotropic parameters, are defined for mean hardwoods and softwoods and for contrasted wood types. GA-dependence calculations are in close agreement with published experimental results and allow comparing the sensitivity of different woods to GA. Calculated trends in damping coefficient (tan delta) and in specific modulus of elasticity (E'/rho) allow reconstructing the general tan delta-E'/rho statistical relationships previously reported. Trends for woods with different mechanical parameters merge into a single curve if anisotropic ratios (both elastic and of damping) are correlated between them, and with axial properties, as is indicated by the collected data. On the other hand, varying damping coefficient independently results in parallel curves, which coincide with observations on chemically modified woods, either “artificially”, or by natural extractives.
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