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Author |
Scotti, I.; Gugerli, F.; Pastorelli, R.; Sebastiani, F.; Vendramin, G.G. |
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Title |
Maternally and paternally inherited molecular markers elucidate population patterns and inferred dispersal processes on a small scale within a subalpine stand of Norway spruce (Picea abies [L.] Karst.) |
Type |
Journal Article |
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Year |
2008 |
Publication |
Forest Ecology and Management |
Abbreviated Journal |
For. Ecol. Manage. |
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Volume |
255 |
Issue |
11 |
Pages |
3806-3812 |
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Keywords |
chloroplast microsatellites; mitochondrial minisatellites; pollen/seed dispersal; demography; spatial autocorrelation |
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Abstract |
The within-population spatial structure of genetic diversity is shaped by demographic processes, including historical accidents such as forest perturbations. Information drawn from the analysis of the spatial distribution of genetic diversity is therefore inherently linked to demographic-historical processes that ultimately determine the fate of populations. All adult trees and saplings in a 1.4-ha plot within a mixed Norway spruce (Picea abies [L.] Karst) stand were characterised by means of chloroplast (paternally inherited) markers, and a large sub-sample of these were genotyped at mitochondrial (maternally inherited) molecular markers. These data were used to analyse the spatial distribution of genetic variation and to compare the patterns corresponding to the two marker types. The plot presented non-homogeneous local stem density in the younger cohorts, and the indirect effect of this source of variation on the spatial genetic structure was investigated. Results suggest that (i) spatially limited seed dispersal induced patchiness in genotype distribution, while pollen flow had a homogenising effect; (ii) deviations from random spatial structure were stronger in the demographically most stable portions of the stand, while they were weaker where sudden bursts of regeneration occurred; (iii) spatially overlapping adult and sapling cohorts displayed the same spatial genetic structure (stronger on stable areas, weaker in portions of the stand undergoing events of intense regeneration), which was substantiated by the influence of local demographic processes. Regeneration dynamics as modulated by demography thus influences the distribution of genetic diversity within the stand both in the younger life stages and in the adult population. (C) 2008 Elsevier B.V. All rights reserved. |
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[Scotti, I.] INRA, UMR 0745, ECOFOG, F-97387 Kourou, France, Email: ivan.scotti@kourou.cirad.fr |
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ELSEVIER SCIENCE BV |
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ISSN |
0378-1127 |
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ISI:000257019100019 |
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no |
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Call Number |
EcoFoG @ eric.marcon @ |
Serial |
137 |
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Author |
Dejean, A.; Djieto-Lordon, C.; Cereghino, R.; Leponce, M. |
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Title |
Ontogenetic succession and the ant mosaic: An empirical approach using pioneer trees |
Type |
Journal Article |
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Year |
2008 |
Publication |
Basic and Applied Ecology |
Abbreviated Journal |
Basic Appl. Ecol. |
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Volume |
9 |
Issue |
3 |
Pages |
316-323 |
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Keywords |
ant-plant relationships; dynamics of associations; myrmecophytes; species turnover; tropical rainforests |
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Abstract |
Arboreal ant mosaics have been intensively investigated, but what generates these mosaics remains poorly understood. In this paper, we hypothesize that the dynamics of arboreal ant mosaics could be better understood by examining the ontogenetic succession of ants in tropical trees. We used three African pioneer tree species as biological models. Lophira alata (Ochnaceae) is a long-lived species that does not furnish any reward (i.e., extra-floral nectaries [EFNs], shelter) to ants, Anthocleista vogelii (Gentianaceae) bears extremely well-developed EFNs, and Barteria fistulosa (Passifloraceae) is a long-lived myrmecophyte providing both EFNs and domatia. For both L. alata and A. vogelii, we noted a succession of different associated ants as the plants grew and aged. Ground-nesting, arborealforaging ant species were the first associates, followed by arboreal species that build nests with the leaves of their host trees, together with some species nesting opportunistically in pre-existing cavities. Carton-building Crematogaster species were the last in this succession. The presence of EFNs on A. vogelii slows species turnover, demonstrating that the plant exerts some control over its ant associates. The comparison with B. fistulosa, which generally remains associated with the same plant-ant species during its entire ontogeny, highlights the importance of the selective attractiveness of the trees for their associated ants – or, perhaps, the existence of plant filters that screen arriving ants. (C) 2007 Gesellschaft fur Okologie. Published by Elsevier GmbH. All rights reserved. |
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Address |
[Dejean, Alain] CNRS Guyane, UPS 2561, F-97300 Cayenne, France, Email: alain.dejean@wanadoo.fr |
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ELSEVIER GMBH, URBAN & FISCHER VERLAG |
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ISSN |
1439-1791 |
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Notes |
ISI:000256734600013 |
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no |
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Call Number |
EcoFoG @ eric.marcon @ |
Serial |
138 |
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Author |
Hattenschwiler, S.; Aeschlimann, B.; Couteaux, M.M.; Roy, J.; Bonal, D. |
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Title |
High variation in foliage and leaf litter chemistry among 45 tree species of a neotropical rainforest community |
Type |
Journal Article |
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Year |
2008 |
Publication |
New Phytologist |
Abbreviated Journal |
New Phytol. |
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Volume |
179 |
Issue |
1 |
Pages |
165-175 |
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Keywords |
French Guiana; interspecific and intraspecific variation; leaf litter traits; neotropical rainforest; nitrogen; nutrient resorption; phosphorus; stoichiometry |
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Abstract |
Distinct ecosystem level carbon : nitrogen : phosphorus (C : N : P) stoichiometries in forest foliage have been suggested to reflect ecosystem-scale selection for physiological strategies in plant nutrient use. Here, this hypothesis was explored in a nutrient-poor lowland rainforest in French Guiana. Variation in C, N and P concentrations was evaluated in leaf litter and foliage from neighbour trees of 45 different species, and the litter concentrations of major C fractions were also measured. Litter C ranged from 45.3 to 52.4%, litter N varied threefold (0.68-2.01%), and litter P varied seven-fold (0.009-0.062%) among species. Compared with foliage, mean litter N and P concentrations decreased by 30% and 65%, respectively. Accordingly, the range in mass-based N : P shifted from 14 to 55 in foliage to 26 to 105 in litter. Resorption proficiencies indicated maximum P withdrawal in most species, but with a substantial increase in variation in litter P compared with foliage. These data suggest that constrained ecosystem-level C : N : P ratios do not preclude the evolution of highly diversified strategies of nutrient use and conservation among tropical rainforest tree species. The resulting large variation in litter quality will influence stoichiometric constraints within the decomposer food web, with potentially far-ranging consequences on nutrient dynamics and plant-soil feedbacks. |
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Address |
[Haettenschwiler, Stephan; Aeschlimann, Beat; Couteaux, Marie-Madeleine; Roy, Jacques] CEFE, CNRS, F-34293 Montpellier 5, France, Email: stephan.hattenschwiler@cefe.cnrs.fr |
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BLACKWELL PUBLISHING |
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ISSN |
0028-646X |
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Notes |
ISI:000256412500017 |
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no |
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Call Number |
EcoFoG @ eric.marcon @ |
Serial |
139 |
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Author |
Grangier, J.; Dejean, A.; Male, P.J.G.; Orivel, J. |
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Title |
Indirect defense in a highly specific ant-plant mutualism |
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Journal Article |
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Year |
2008 |
Publication |
Naturwissenschaften |
Abbreviated Journal |
Naturwissenschaften |
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Volume |
95 |
Issue |
10 |
Pages |
909-916 |
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Keywords |
Allomerus decemarticulatus; Hirtella physophora; indirect defense; myrmecophytes; optimal defense theory |
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Abstract |
Although associations between myrmecophytes and their plant ants are recognized as a particularly effective form of protective mutualism, their functioning remains incompletely understood. This field study examined the ant-plant Hirtella physophora and its obligate ant associate Allomerus decemarticulatus. We formulated two hypotheses on the highly specific nature of this association: (1) Ant presence should be correlated with a marked reduction in the amount of herbivory on the plant foliage; (2) ant activity should be consistent with the “optimal defense” theory predicting that the most vulnerable and valuable parts of the plant are the best defended. We validated the first hypothesis by demonstrating that for ant-excluded plants, expanding leaves, but also newly matured ones in the long term, suffered significantly more herbivore damage than ant-inhabited plants. We showed that A. decemarticulatus workers represent both constitutive and inducible defenses for their host, by patrolling its foliage and rapidly recruiting nestmates to foliar wounds. On examining how these activities change according to the leaves' developmental stage, we found that the number of patrolling ants dramatically decreased as the leaves matured, while leaf wounds induced ant recruitment regardless of the leaf's age. The resulting level of these indirect defenses was roughly proportional to leaf vulnerability and value during its development, thus validating our second hypothesis predicting optimal protection. This led us to discuss the factors influencing ant activity on the plant's surface. Our study emphasizes the importance of studying both the constitutive and inducible components of indirect defense when evaluating its efficacy and optimality. |
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[Grangier, Julien; Dejean, Alain; Male, Pierre-Jean G.; Orivel, Jerome] Univ Toulouse 3, Lab Evolut & Diversite Biol, CNRS, UMR 5174, F-31062 Toulouse 9, France, Email: grangier@cict.fr |
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SPRINGER |
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ISSN |
0028-1042 |
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Notes |
ISI:000259737600002 |
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EcoFoG @ eric.marcon @ |
Serial |
207 |
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Author |
Vendramin, G.G.; Fady, B.; Gonzalez-Martinez, S.C.; Hu, F.S.; Scotti, I.; Sebastiani, F.; Soto, A.; Petit, R.J. |
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Title |
Genetically depauperate but widespread: The case of an emblematic mediterranean pine |
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Journal Article |
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Year |
2008 |
Publication |
Evolution |
Abbreviated Journal |
Evolution |
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Volume |
62 |
Issue |
3 |
Pages |
680-688 |
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Keywords |
chloroplast microsatellites; conservation genetics; diversity depletion; human impact; Pinus pinea |
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Abstract |
Genetic variation is generally considered a prerequisite for adaptation to new environmental conditions. Thus the discovery of genetically depauperate but geographically widespread species is unexpected. We used 12 paternally inherited chloroplast microsatellites to estimate population genetic variation across the full range of an emblematic circum-Mediterranean conifer, stone pine (Pinus pinea L.). The same chloroplast DNA haplotype is fixed in nearly all of the 34 investigated populations. Such a low level of variation is consistent with a previous report of very low levels of diversity at nuclear loci in this species. Stone pine appears to have passed through a severe and prolonged demographic bottleneck, followed by subsequent natural- and human-mediated dispersal across the Mediterranean Basin. No other abundant and widespread plant species has as little genetic diversity as P. pinea at both chloroplast and nuclear markers. However, the species harbors a nonnegligible amount of variation at adaptive traits. Thus a causal relationship between genetic diversity, as measured by marker loci, and the evolutionary precariousness of a species, cannot be taken for granted. |
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Address |
[Vendramin, Giovanni G.] Ist Genet Vegetale, Sez Firenze, Florence, Italy, Email: petit@pierroton.inra.fr |
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BLACKWELL PUBLISHING |
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ISSN |
0014-3820 |
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Notes |
ISI:000253758600016 |
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no |
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Call Number |
EcoFoG @ eric.marcon @ |
Serial |
141 |
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Author |
Tindo, M.; Kenne, M.; Dejean, A. |
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Title |
Advantages of multiple foundress colonies in Belonogaster juncea juncea L.: greater survival and increased productivity |
Type |
Journal Article |
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Year |
2008 |
Publication |
Ecological Entomology |
Abbreviated Journal |
Ecol. Entomol. |
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Volume |
33 |
Issue |
2 |
Pages |
293-297 |
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Keywords |
colony development; evolution of eusociality; fitness; Polistinae; productivity |
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Abstract |
1. The ecological hypothesis predicts that multiple foundress colonies of social wasps may have a better survival rate and produce more brood per capita than single foundress colonies. With the aim of verifying if these characteristics exist in the primitively eusocial wasp species Belonogaster juncea juncea (L.), we monitored 49 foundations, including 13 single and 36 multiple foundress colonies, in Cameroon. 2. Multiple foundress colonies were significantly more successful than single foundress colonies in producing at least one adult. 3. The total productivity of the colonies increased significantly with the number of associated foundresses, but the productivity per capita did not. No single foundress colony reached the sexual phase, while eight (21.6%) multiple foundress colonies did. Males were produced in only five colonies, so that the sex ratio was biased in favour of females. 4. These results suggest that because of the strong ecological constraints on solitary nesting, survival and high colony productivity are two advantages of multiple foundress colonies in B. j. juncea. 5. The decreasing per capita productivity concomitant with an increasing number of females noted in this study illustrates once again Michener's paradox. The coefficient of variance of the per capita productivity significantly decreased with group size, as Wenzel and Pickering suggested in the model they created to explain the paradox. 6. Ecological factors may act in conjunction with other factors, such as genetic relatedness between associated foundresses, to promote joining behaviour in B. j. juncea. |
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[Tindo, Maurice; Kenne, Martin] Univ Douala, Fac Sci, BP Douala, Cameroon, Email: jtindo2000@yahoo.fr |
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BLACKWELL PUBLISHING |
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ISSN |
0307-6946 |
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Notes |
ISI:000253710000017 |
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no |
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Call Number |
EcoFoG @ eric.marcon @ |
Serial |
142 |
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Author |
Brendel, O.; Le Thiec, D.; Scotti-Saintagne, C.; Bodenes, C.; Kremer, A.; Guehl, J.M. |
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Title |
Quantitative trait loci controlling water use efficiency and related traits in Quercus robur L |
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Journal Article |
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Year |
2008 |
Publication |
Tree Genetics & Genomes |
Abbreviated Journal |
Tree Genet. Genomes |
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Volume |
4 |
Issue |
2 |
Pages |
263-278 |
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Keywords |
Quercus robur; carbon isotope composition; delta C-13; water use efficiency; QTL |
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Abstract |
Genetic variation for intrinsic water use efficiency (W-i) and related traits was estimated in a full-sib family of Quercus robur L. over 3 years. The genetic linkage map available for this F1 family was used to locate quantitative trait loci (QTL) for W-i, as estimated by leaf carbon stable isotope composition (delta C-13) or the ratio of net CO2 assimilation rate (A) to stomatal conductance to water vapour (g(w)) and related leaf traits. Gas exchange measurements were used to standardize estimates of A and g(w) and to model the sensitivity of gw to leaf-to-air vapour pressure deficit (sg(VPD)). delta C-13 varied by more than 3% among the siblings, which is equivalent to 40% variation of W-i. Most of the studied traits exhibited high clonal mean repeat-abilities (> 50%; proportion of clonal mean variability in global variance). Repeatabilities for delta C-13, leaf mass per area (LMA) and leaf nitrogen content were higher than 70%. For delta C-13, ten QTLs were detected, one of which was detected repeatedly for all 3 years and consistently explained more than 20% of measured variance. Four genomic regions were found in which co-localizing traits linked variation in W-i to variations in leaf chlorophyll and nitrogen content, LMA and sg(VPD). A positive correlation using clonal means between delta C-13 and A/g(w), as well as a co-localisation of QTL detected for both traits, can be seen as validation of the theoretical model linking the genetic architecture of these two traits. |
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Address |
[Brendel, Oliver; Le Thiec, Didier; Guehl, Jean-Marc] Ctr INRA Nancy, UMR INRA UHP 1137, F-54280 Seichamps, France, Email: brendel@nancy.inra.fr |
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Publisher |
SPRINGER HEIDELBERG |
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ISSN |
1614-2942 |
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Notes |
ISI:000253091100013 |
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Call Number |
EcoFoG @ eric.marcon @ |
Serial |
143 |
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Author |
Bleron, L.; Duchanois, G.; Thibaut, B. |
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Title |
Characteristic properties of embedding strength for the nailing of the gonfolio rose (Qualea rosea Aubl.) |
Type |
Journal Article |
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Year |
2008 |
Publication |
Holzforschung |
Abbreviated Journal |
Holzforschung |
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Volume |
62 |
Issue |
1 |
Pages |
86-90 |
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Keywords |
embedding strength; Eurocode V; nail |
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Abstract |
Experimental results are presented with single nail joints of gonfolo rose which were loaded at different grain angles and compared to results obtained by Eurocode V. A wide range of embedding strength tests was conducted. The embedding behaviour across the grain was also investigated with a specific test apparatus. The results were analysed and modelled in terms of strength. Initial loading and unloading stiffness of the timber have been taken into account. The embedment strength of the nails varied according to the angle between the direction of loading and that to the grain. This work is part of a larger research project to establish a computer program for the prediction of stiffness and limit strengths of all timber-to-timber and timber-to-steel joints. |
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Address |
[Bleron, Laurent] LABOMAP ENSAM, F-71250 Poret De Paris, Cluny, France, Email: laurent.bleron@cluny.ensam.fr |
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WALTER DE GRUYTER & CO |
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ISSN |
0018-3830 |
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Notes |
ISI:000252041400013 |
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no |
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EcoFoG @ eric.marcon @ |
Serial |
144 |
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Author |
Yatabe, Y.; Kane, N.C.; Scotti-Saintagne, C.; Rieseberg, L.H. |
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Title |
Rampant gene exchange across a strong reproductive barrier between the annual sunflowers, Helianthus annuus and H-petiolaris |
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Journal Article |
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Year |
2007 |
Publication |
Genetics |
Abbreviated Journal |
Genetics |
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Volume |
175 |
Issue |
4 |
Pages |
1883-1893 |
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Abstract |
Plant species may remain morphologically distinct despite gene exchange with congeners, yet little is known about the genomewide pattern of introgression among species. Here we analyze the effects of persistent gene flow on genomic differentiation between the sympatric sunflower species Helianthus annuus and H. petiolaris. While the species are strongly isolated in testcrosses, genetic distances at 108 microsatellite loci and 14 sequenced genes are highly variable and much lower (on average) than for more closely related but historically allopatric congeners. Our analyses failed to detect a positive association between levels of genetic differentiation and chromosomal rearrangements (as reported in a prior publication) or proximity to QTL for morphological differences or hybrid sterility. However, a significant increase in differentiation was observed for markers within 5 cM of chromosomal breakpoints. Together, these results suggest that islands of differentiation between these two species are small, except in areas of low recombination. Furthermore, only microsatellites associated with ESTs were identified as outlier loci in tests for selection, which might indicate that the ESTs themselves are the targets of selection rather than linked genes (or that coding regions are not randomly distributed). In general, these results indicate that even strong and genetically complex reproductive barriers cannot prevent widespread introgression. |
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Address |
Indiana Univ, Dept Biol, Bloomington, IN 47405 USA, Email: lriesebe@indiana.edu |
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Publisher |
GENETICS |
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ISSN |
0016-6731 |
ISBN |
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Notes |
ISI:000246448800029 |
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no |
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Call Number |
EcoFoG @ eric.marcon @ |
Serial |
216 |
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Author |
Schimann, H.; Ponton, S.; Hattenschwiler, S.; Ferry, B.; Lensi, R.; Domenach, A.M.; Roggy, J.C. |
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Title |
Differing nitrogen use strategies of two tropical rainforest late successional tree species in French Guiana: Evidence from N-15 natural abundance and microbial activities |
Type |
Journal Article |
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Year |
2008 |
Publication |
Soil Biology & Biochemistry |
Abbreviated Journal |
Soil Biol. Biochem. |
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Volume |
40 |
Issue |
2 |
Pages |
487-494 |
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Keywords |
soil; litter; nitrate; nitrification; tree rooting; N-15; Eperua falcata; Dicorynia guianensis; tropical forest |
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Abstract |
Previous studies in lowland tropical rainforests of French Guiana showed that, among non-N-2-fixing trees, two groups of late successional species contrasting in their leaf N-15 natural abundance coexist, suggesting two different main ways of nitrogen acquisition. Two abundant late-successional species typically co-occurring in rainforests in French Guiana, namely Eperua falcata and Dicorynia guianensis, were chosen as representative of each group. Stable isotope techniques and measurements of potentials of microbial N transformation were performed to assess to what extent leaf N-15 natural abundance of these species could be related to (i) delta N-15 signatures of soil mineral N sources and (ii) the capacity of soil to express nitrification and denitrification (both processes being directly involved in the balance between NH4+ and NO3-). Soil delta N-15-NH4+ was roughly similar to leaf delta N-15 of D. guianensis (around 3.5 parts per thousand), suggesting a preferential use of NH4+, whereas in E. falcata, leaf delta N-15 values were closer to root delta N-15-NO3- values (0.2 and -2.0 parts per thousand, respectively), suggesting a preferential use of NO3-. These differences in N source utilization were not accompanied by differences in availability in soil NO3- or in intensity of microbial functions responsible for soil N mineral evolution. However, (i) under both tree species, these functions showed clear spatial partitioning, with denitrification occurring potentially in soil and nitrification in the litter layer, and (ii) E falcata fine roots colonized the litter layer much more strongly than D. guianensis fine roots. This strongly suggests that (i) the contrasted leaf delta N-15 values found in the two late-successional species reveal distinct N acquisition strategies and (ii) the ability of roots to predominantly exploit the litter layer (E falcata) or the soil (D. guianensis) may constitute an important explanation of the observed differences. A complementarity between tree species, based on mineral N resource partitioning (itself resulting from a spatially structured location of the microbial functions responsible for the balance between NH4+ and NO3-), n thus be supposed. (c) 2007 Elsevier Ltd. All rights reserved. |
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[Schimann, Heidy; Ponton, Stephane; Domenach, Anne-Marie; Roggy, Jean-Christophe] UMR Ecol Forets Guyane, F-97387 Kourou, French Guiana, Email: heidy_schimann@cirad.fr |
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PERGAMON-ELSEVIER SCIENCE LTD |
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0038-0717 |
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ISI:000251655800021 |
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EcoFoG @ eric.marcon @ |
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146 |
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