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The period that begins with the reflections and debates around the new constitution in Tunisia is also the one of territorial reform. Questions about it and, more generally, about the recasting of local authorities and equalization rules has emerged as a major political and social issue. This article shows that what is played out in this country cannot free itself on the one hand from the territorial grids that have existed for several decades, on the other hand from the urban fact that takes more and more importance in the structuring of activities and wealth. This article finally stresses the need to take account of the representations and perceptions of the populations to carry out such a reform.

Many species show a time-lagged response to climate change, a phenomenon called climatic debt. Here, Bertrand and colleagues show that climate severity and plant tolerance to climate warming mainly influence the climatic debt of forest herbaceous plant communities.

Plant defense responses against pathogens often involve the restriction of the pathogen to its site of penetration achieved through the combined effects of the hypersensitive response (HR) and its tightly connected localized acquired resistance (LAR). The tobacco DD9-3 expressed sequence tag was previously isolated from a screen designed to isolate genes induced early during the HR, thus potentially involved in the induction/regulation of the HR or LAR. Translation of the open reading frame of DD9-3 revealed a leucine-rich repeat (LRR) domain highly homologous with the receptor domain of a receptor kinase, suggesting a potential function in signaling pathways. The full-length cDNA was cloned. It encodes a small (232 amino acids) LRR protein, designated Nicotiana tabacum leucine-rich protein 1 (NtLRP1), containing a signal peptide, four leucine zipper repeats, five LRR repeats, and a C-terminal domain rich in proline. NtLRP1 expression is induced early during the HR initiated by elicitins, Ralstonia solanacearum, or Tobacco mosaic virus. NtLRP1 coupled with the green fluorescent protein localizes to the endoplasmic reticulum (ER). Loss-of-function through virus-induced gene silencing or through RNA interference did not modify the elicitin-induced HR or LAR. Gain-of-function experiments through transient Agrobacterium tu-mefaciens-mediated NtLRP1 expression in tobacco leaves caused the suppression of the HR induced by 2 nM elicitin and delayed the HR when the elicitin was applied at higher concentrations. The results suggest that NtLRP1 acts as a modulator of the HR and that retention in the ER is essential for its function.

This article offers a comparative analysis of political divisions of French territory proposed between the mid-nineteenth century and the 2010s. The analysis of these regional maps allows us to identify some spatial structures specific to the French regionalist imaginary. Some geographical areas appear repeatedly and seem to be obvious while other areas look more uncertain. Mapping these regional divisions offers a general prism proper to question the new regional units proposed by the president of the French Republic in a bill submitted to Parliament in June 2014.

Focusing on Normandy, this paper intends to show that French “regions” are ambiguous realities, despite the efforts of institutionnalisation made since fifty years. The notion of “region” is actually associated to heterogeneous meanings that reduces its ability to be grasped by various stakeholders involved in their politicisation (political elites, journalists, citizens). A survey conducted in Normandy about the way elected officials perceive their region reveals that the various significations of the French “region” refer to disconnected spatial frameworks, generating deep and lasting confusions and geopolitical contradictions. Recurrent debates about a possible fusion of the “regions” Basse-Normandie et Haute-Normandie provides a significative example of existing ambiguities and deadlocks.

Thinking about what Europe is, about its limits often consists in trying to identify something such as a European identity, a common project or behavior in space. The approach by mental representations can be supplemented by more subjective perspective, the perception of borders. This article made from the survey results of the research project Eurobroadmap about the vision of Europe in the world allows identifying a typology of spatial forms of the boundaries of Europe. Interpretative mental maps by students show a configuration variable geometry of Europe, as the process of the construction of the European Union, with limits more or less marked. A comparison between the mental maps of different countries (members of the European Union, neighboring countries, remote countries…) shows the differences in perceptions of Europe.

Higher vegetation types are generally determined by successive approximations and defined by a common consent. Instead, they might be statistically determined and repeated, according to a numerical method called ‘socio-ecology’. This method deals only with floristical data, but gives them an ecological meaning by a previous calibration of the relations between plants, computed as ecological indices. It is applied to a pair of two homologous samples, each having 2.000 relevés and coming from the 60.000 relevés stored in the French data bank ‘Sophy’. Each sample covers the main ecological gradients of the bank, it defines a hierarchy of vegetation types and it explains half the peculiarity of a type with only 10 to 30 discriminant plants, out of the 5.000 plants observed in the relevés. Results : 1) The discriminant plants may characterize the vegetation types, including the higher ones, in a coherent and readable form. 2) In the two independent classifications, having different structures, the same vegetation types are repeated. They are the reciprocal nearest types, in the socio-ecological space. Though the two classifications have no one relevé in common, the repeated types have nearly the same discriminant plants. 3) At the highest level, two clear-cut main types show the difference between light and shadow. The same herbaceous discriminant plants, for a type, and the ligneous or sciaphilous ones, for the other, have similar fidelities and constancies in the two classifications. 4) Such a numerical agreement, instead of common consent, appears again in the sub-types, which remind the classical ones, but which are repeatable.

Higher vegetation types are generally determined by successive approximations and defined by a common consent. Instead, they might be statistically determined and repeated, according to a numerical method called ‘socio-ecology’. This method deals only with floristical data, but gives them an ecological meaning by a previous calibration of the relations between plants, computed as ecological indices. It is applied to a pair of two homologous samples, each having 2.000 relevés and coming from the 60.000 relevés stored in the French data bank ‘Sophy’. Each sample covers the main ecological gradients of the bank, it defines a hierarchy of vegetation types and it explains half the peculiarity of a type with only 10 to 30 discriminant plants, out of the 5.000 plants observed in the relevés. Results : 1) The discriminant plants may characterize the vegetation types, including the higher ones, in a coherent and readable form. 2) In the two independent classifications, having different structures, the same vegetation types are repeated. They are the reciprocal nearest types, in the socio-ecological space. Though the two classifications have no one relevé in common, the repeated types have nearly the same discriminant plants. 3) At the highest level, two clear-cut main types show the difference between light and shadow. The same herbaceous discriminant plants, for a type, and the ligneous or sciaphilous ones, for the other, have similar fidelities and constancies in the two classifications. 4) Such a numerical agreement, instead of common consent, appears again in the sub-types, which remind the classical ones, but which are repeatable.

In vegetation science, an exchange between two floristical data banks increases the ecological gradient of the registered releves. Therefore, it also increases the discrimination between the behaviours of plants and, because of this, the distinctness of types of plant community. In practice, an exchange is restricted, on one hand by the priority given to the authors for processing their own releves and, on the other hand, by the interest of a bank which needs a benefit from its registered files, in order to support and develop the data processing. On the other hand, there is another kind of exchange, that of the socio-ecological calibrations of plants, which keeps the data in their initial bank and so protects everyone's interest. That exchange unites the gradients of the banks and improves the understanding of the releves. The socioecological calibI-ation of a plant is the set of its fidelities compared to all the plants of the bank. The calibration defines a statistical space of fidelities, where distances express the implicit ecological differences and determine the classification of relevès in types of plant communities corresponding to homogenous environments. The melting of the calibrations coming from two banks defines a common space of fidelities where plants and releves are localized and classified according to the common gradient covered by the two banks together.

The proposed method is based only on tlotistical data and nevertheless classifies the relevés into ecological groupings, corresponding to as similar environments as possible. It begins by calibrating the behaviour of each plant along a large gradient, in a national data bank of floristical releves, on the scale of France, the bank Sophy. It calibrates the behaviour of a plant by its fidelities to the 5,626 other plants of the bank, which are considered as indices of the environment. It defines a statistical space having 5.626 dimensions in which: 1) an axis measures the fidelity to a plant, considered as an ecological index; 2) a dot corresponds to the behaviour of a plant towards the indices; 3) the distance between two dots expresses the ecological difference between two behaviours; 4) the centre of gravity for the plants of a releve indicates the probable position of the relev6; 5) the distance between two releves expresses their ecological difference. Compared with this method, the correspondence factor analysis CFA: 1) locates the releves in a space, according to the fidelities of plants to releves, showing their floristical differences; 2) gives a weight to a plant according to its rarity, not its ecological behaviour; 3) deals only with subsets of the releves and rehandle the subsets by successive approximations; 4) transfers onto the graphs the empirical and intuitive method of a naturalist during field-work, The method is applied to about 400 releves in a district in the Northern Vosges (France). It generates an automatic classification of the releves, at several levels of synthesis. including the upper levels above the phytosociological classes. It explains half of the peculiarity of a type of plant community with 10 to 30 discriminant plants, which are the quantitative and gradual homologues of characteristic species.

The proposed method is based only on tlotistical data and nevertheless classifies the relevés into ecological groupings, corresponding to as similar environments as possible. It begins by calibrating the behaviour of each plant along a large gradient, in a national data bank of floristical releves, on the scale of France, the bank Sophy. It calibrates the behaviour of a plant by its fidelities to the 5,626 other plants of the bank, which are considered as indices of the environment. It defines a statistical space having 5.626 dimensions in which: 1) an axis measures the fidelity to a plant, considered as an ecological index; 2) a dot corresponds to the behaviour of a plant towards the indices; 3) the distance between two dots expresses the ecological difference between two behaviours; 4) the centre of gravity for the plants of a releve indicates the probable position of the relev6; 5) the distance between two releves expresses their ecological difference. Compared with this method, the correspondence factor analysis CFA: 1) locates the releves in a space, according to the fidelities of plants to releves, showing their floristical differences; 2) gives a weight to a plant according to its rarity, not its ecological behaviour; 3) deals only with subsets of the releves and rehandle the subsets by successive approximations; 4) transfers onto the graphs the empirical and intuitive method of a naturalist during field-work, The method is applied to about 400 releves in a district in the Northern Vosges (France). It generates an automatic classification of the releves, at several levels of synthesis. including the upper levels above the phytosociological classes. It explains half of the peculiarity of a type of plant community with 10 to 30 discriminant plants, which are the quantitative and gradual homologues of characteristic species.

In vegetation science, an exchange between two floristical data banks increases the ecological gradient of the registered releves. Therefore, it also increases the discrimination between the behaviours of plants and, because of this, the distinctness of types of plant community. In practice, an exchange is restricted, on one hand by the priority given to the authors for processing their own releves and, on the other hand, by the interest of a bank which needs a benefit from its registered files, in order to support and develop the data processing. On the other hand, there is another kind of exchange, that of the socio-ecological calibrations of plants, which keeps the data in their initial bank and so protects everyone's interest. That exchange unites the gradients of the banks and improves the understanding of the releves. The socioecological calibI-ation of a plant is the set of its fidelities compared to all the plants of the bank. The calibration defines a statistical space of fidelities, where distances express the implicit ecological differences and determine the classification of relevès in types of plant communities corresponding to homogenous environments. The melting of the calibrations coming from two banks defines a common space of fidelities where plants and releves are localized and classified according to the common gradient covered by the two banks together.

Biodiversity changes are lagging behind current climate warming. The underlying determinants of this climatic debt are unknown and yet critical to understand the impacts of climate change on the present biota and improve forecasts of biodiversity changes. Here we assess determinants of climatic debt accumulated in French forest herbaceous plant communities between 1987 and 2008 (that is, a 1.05 °C mean difference between the observed and bioindicated temperatures). We show that warmer baseline conditions predispose plant communities to larger climatic debts, and that climate warming exacerbates this response. Forest plant communities, however, are absorbing part of the temperature increase mainly through the species' ability to tolerate changing climate. As climate warming is expected to accelerate during the twenty-first century, plant migration and tolerance to climatic stresses probably will be insufficient to absorb this impact posing threats to the sustainability of forest plant communities.

The application of the criterion of fidelity of plants to plants over four millions botanical observations in France is considered to characterize the ecology of 215,000 phytosociological surveys. Among those discriminant plants, some are missing of the surveys, but they can have a certain probability of occurrence: these plants are called "probable plants" and they represent the "probable flora" of a territory. The study of their geographical distribution shows ecological gradients of flora across France in a better way than only considering the botanical observations. In fact, this method mitigates the discontinuities of taxa observations whose absence may be due to historical and/or anthropogenic factors., (Copyright © 2013 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

Climate change is driving latitudinal and altitudinal shifts in species distribution worldwide, leading to novel species assemblages. Lags between these biotic responses and contemporary climate changes have been reported for plants and animals. Theoretically, the magnitude of these lags should be greatest in lowland areas, where the velocity of climate change is expected to be much greater than that in highland areas. We compared temperature trends to temperatures reconstructed from plant assemblages (observed in 76,634 surveys) over a 44-year period in France (1965-2008). Here we report that forest plant communities had responded to 0.54 °C of the effective increase of 1.07 °C in highland areas (500-2,600 m above sea level), while they had responded to only 0.02 °C of the 1.11 °C warming trend in lowland areas. There was a larger temperature lag (by 3.1 times) between the climate and plant community composition in lowland forests than in highland forests. The explanation of such disparity lies in the following properties of lowland, as compared to highland, forests: the higher proportion of species with greater ability for local persistence as the climate warms, the reduced opportunity for short-distance escapes, and the greater habitat fragmentation. Although mountains are currently considered to be among the ecosystems most threatened by climate change (owing to mountaintop extinction), the current inertia of plant communities in lowland forests should also be noted, as it could lead to lowland biotic attrition., (©2011 Macmillan Publishers Limited. All rights reserved)

This article presents a synthesis of the relationships between plants and climates at the scale of France, based on a probabilistic classification of 1874 bio-indicators. This classification defines plants groups that indicate the climate, named phytoclimates, expressing the climatic gradients in France. This classification shows 210 phytoclimatic groups distributed into ten cluster levels. The analysis of the various hierarchical levels shows two main phytoclimates testifying the importance of the marine masses and the altitude. The analysis of the third hierarchical level underlines particular phytoclimates which would not be easily recognizable by only analysing the overlapping of floristic and climatic territories. This classification allows one to select taxa that are indicators of the climate. The distribution monitoring or modeling of these taxa should show the effects of the global change on the ecosystems.

The influence of climate on plants geography is studied through a probabilistic calibration between a botanical database, containing 12 000 plots, and a meteorological database composed of 574 climatic stations. The calibration measures the climatical optimum (position) and the indicator power (concentration) of 1874 plants for six climatic variables. The validation of these relations is based upon the comparison of the estimation of climate by plants and the values measured by climatic stations near the plots. This validation underlines that plants are accurate (accuracy=88.5%) and stable (stability=96.5%) bio-indicators of climate variables.

Plant defense responses against pathogens often involve the restriction of the pathogen to its site of penetration achieved through the combined effects of the hypersensitive response (HR) and its tightly connected localized acquired resistance (LAR). The tobacco DD9-3 expressed sequence tag was previously isolated from a screen designed to isolate genes induced early during the HR, thus potentially involved in the induction/regulation of the HR or LAR. Translation of the open reading frame of DD9-3 revealed a leucine-rich repeat (LRR) domain highly homologous with the receptor domain of a receptor kinase, suggesting a potential function in signaling pathways. The full-length cDNA was cloned. It encodes a small (232 amino acids) LRR protein, designated Nicotiana tabacum leucine-rich protein 1 (NtLRP1), containing a signal peptide, four leucine zipper repeats, five LRR repeats, and a C-terminal domain rich in proline. NtLRP1 expression is induced early during the HR initiated by elicitins, Ralstonia solanacearum, or Tobacco mosaic virus. NtLRP1 coupled with the green fluorescent protein localizes to the endoplasmic reticulum (ER). Loss-of-function through virus-induced gene silencing or through RNA interference did not modify the elicitin-induced HR or LAR. Gain-of-function experiments through transient Agrobacterium tumefaciens-mediated NtLRP1 expression in tobacco leaves caused the suppression of the HR induced by 2 nM elicitin and delayed the HR when the elicitin was applied at higher concentrations. The results suggest that NtLRP1 acts as a modulator of the HR and that retention in the ER is essential for its function.

Laminarin, a beta-1,3 glucan with single beta-glucose branches at position 6, was chemically sulfated to produce PS3 with a degree of sulfation of 2.4. PS3 has previously been shown to activate the salicylic acid (SA) signaling pathway in infiltrated tobacco and Arabidopsis thaliana leaf tissues. Here, we investigated whether PS3 induces systemic defense and resistance responses in tobacco. Using a radiolabeled compound, it was first demonstrated that PS3 remains strictly localized to the infiltrated tissues. PS3 is also resistant to beta-glucanase degradation. In transgenic PR1-beta-glucuronidase (GUS) tobacco plants, PS3 causes a strong increase in GUS activity in treated tissues but none in untreated leaves. PS3-infiltrated tissues challenged with tobacco mosaic virus (TMV) 8 d after elicitor application show a decrease in both the lesion number and the lesion size, whereas treatment with laminarin, the unsulfated native glucan, affected only the lesion number. PS3 does not induce systemic acquired resistance to TMV. PS3 and laminarin show synergistic effects in promoting the oxidative burst in tobacco cell suspensions and in increasing the expression of genes encoding O-methyltransferases of the phenylpropanoid pathway in tobacco plants. No synergistic effect was observed on the expression of either the SA-dependent acidic PR1 gene or the ethylene-dependent basic PR5 gene in tobacco plants.

Plant defense responses against pathogens often involve the restriction of the pathogen to its site of penetration. Restriction is achieved through the combined effects of the hypersensitive response (HR) and its tightly connected localized acquired resistance (LAR). As LAR is induced by unknown signals released by the cells undergoing the HR, LAR inducing/regulating genes must show a HR-specific pattern of expression. Here, we describe a differential display reverse-transcript polymerase chain reaction (DDRT-PCR) strategy to isolate tobacco expressed sequence tags (ESTs) characterized by such an expression profile, which also characterizes genes involved in the induction/execution of the HR. We compared the DDRT-PCR profile of tobacco cell suspensions treated with beta-megaspermin inducing the HR with that of untreated cells and cells treated with alpha-megaspermin inducing a Defense No Death (DND) phenotype. The expression profile of the selected ESTs was analyzed in tobacco plants expressing a beta-megaspermin-induced HR or a DND phenotype, including LAR, induced by three different elicitors. This comprehensive analysis allowed to identify 24 HR-specific ESTs, half of them shows no or non-significant homology with ESTs and genes in the databases. The other half exhibits homology with genes encoding a receptor-like kinase protein, proteins involved in the regulation of plasma membrane structure, proteins of the ubiquitin/26S proteasome proteolytic system, RNA binding proteins, and a protein hypothesized to be a true regulator of the HR.

Sulfate substituents naturally occurring in biomolecules, such as oligosaccharides and polysaccharides, can play a critical role in major physiological functions in plants and animals. We show that laminarin, a beta-1,3 glucan with elicitor activity in tobacco (Nicotiana tabacum), becomes, after chemical sulfation, an inducer of the salicylic acid (SA) signaling pathway in tobacco and Arabidopsis thaliana. In tobacco cell suspensions, the oxidative burst induced by the laminarin sulfate PS3 was Ca2+ dependent but partially kinase independent, whereas laminarin triggered a strickly kinase-dependent oxidative burst. Cells treated with PS3 or laminarin remained fully responsive to a second application of laminarin or PS3, respectively, suggesting two distinct perception systems. In tobacco leaves, PS3, but not laminarin, caused electrolyte leakage and triggered scopoletin and SA accumulation. Expression of different families of Pathogenesis-Related (PR) proteins was analyzed in wild-type and mutant tobacco as well as in Arabidopsis. Laminarin induced expression of ethylene-dependent PR proteins, whereas PS3 triggered expression of ethylene- and SA-dependent PR proteins. In Arabidopsis, PS3-induced PR1 expression was also NPR1 (for nonexpressor of PR genes1) dependent. Structure-activity analysis revealed that (1) a minimum chain length is essential for biological activity of unsulfated as well as sulfated laminarin, (2) the sulfate residues are essential and cannot be replaced by other anionic groups, and (3) moderately sulfated beta-1,3 glucans are active. In tobacco, PS3 and curdlan sulfate induced immunity against Tobacco mosaic virus infection, whereas laminarin induced only a weak resistance. The results open new routes to work out new molecules suitable for crop protection.

We report on the molecular cloning of the Phytophthora megasperma H20 (PmH20) glycoprotein shown previously as an inducer of the hypersensitive response, of localized acquired resistance and of systemic acquired resistance in tobacco (Nicotiana tabacum), and of the PmH20 alpha- and beta-megaspermin, two elicitins of class I-A and I-B, respectively. The structure of the glycoprotein shows a signal peptide of 20 amino acids followed by the typical elicitin 98-amino acid-long domain and a 77-amino acid-long C-terminal domain carrying an O-glycosylated moiety. The molecular mass deduced from the translated cDNA sequence is 14,920 and 18,676 D as determined by mass spectrometry. This structure together with multiple sequence alignments and phylogenetic analyses indicate that the glycoprotein belongs to class III elicitins. It is the first class III elicitin protein characterized, which we named gamma-megaspermin. We compared the biological activity of the three PmH20 elicitins when applied to tobacco cv Samsun NN plants. Although alpha- and gamma-megaspermin were similarly active, beta-megaspermin was the most active in inducing the hypersensitive response and localized acquired resistance, which was assessed by measuring the levels of acidic and basic pathogenesis-related proteins and of the antioxidant phytoalexin scopoletin. The three elicitins induced similar levels of systemic acquired resistance measured as the expression of acidic PR proteins and is increased resistance to challenge tobacco mosaic virus infection.

Agrobacterium vitis is a common pathogen of grapevine. Most strains utilize tartrate, an abundant compound in grapevine. Strain AB3 carries two tartrate utilization (or TAR) regions: TAR-I (on the large pTrAB3 plasmid) and TAR-II (on the AB3 Ti plasmid). TAR-I and TAR-II were structurally and functionally analyzed and are similar to the TAR-III region from the tartrate utilization plasmid pTrAB4 of the nopaline-type A. vitis strain AB4 (Crouzet and Otten, J. Bacteriol. 1995, 177:6518-6526). The minimal tartrate utilization region of TAR-I contains four genes (ttuA-ttuD). The ttuC gene is homologous to the tartrate dehydrogenase gene from Pseudomonas putida. Outside the minimal region a second ttuC-like gene is found (ttuC') which is transcribed and complements a ttuC mutant. Most grapevine isolates carry one or two of the three characterized TAR regions and show a considerable degree of polymorphism around these regions.

The octopine/cucumopine (o/c) Ti plasmids of Agrobacterium vitis carry two T regions, TA and TB. The TA region resembles the octopine TL region. The TB region contains the auxin synthesis genes TB-iaaM and TB-iaaH and the cucumopine synthesis gene cus. Within the group of o/c isolates, strains 2608 and 2641 are closely related. However, 2641 lacks the TB region. The restriction maps of pTi2608 and pTi2641 were established and showed that the TB deletion resulted from intramolecular recombination between two directly repeated sequences separated by 66 kb in pTi2608. The 2,294-bp repeated sequence lacks inverted repeats and does not duplicate its target site, indicating that it is not a classical bacterial insertion sequence (IS element). It was therefore called an RSAv element (repeated sequence of A. vitis). The RSAv element carries two open reading frames: ORF234 is homologous to the traR gene of the A. tumefaciens nopaline Ti plasmid pTiC58; ORF488 is homologous to the sucrose phosphorylase gene of Leuconostoc mesenteroides and the glucosyl transferase A gene of Streptococcus mutans. The RSAv repeat starts precisely at the start codon of ORF488 and ends two base pairs 3' of the stop codon of ORF234. The structural organization of the RSAv element suggests that the amplification event did not result from a random amplification process. A study of the distribution of the two RSAv copies (RSAv-1 and RSAv-2) in pTi2608 and other o/c isolates indicates that the ancestor o/c Ti plasmid contained only RSAv-1 and that this sequence was duplicated at one point during the divergent evolution of the o/c Ti plasmids.(ABSTRACT TRUNCATED AT 250 WORDS)

The octopine/cucumopine (o/c) strains of Agrobacterium vitis are divided into limited (LHR) and wide host range (WHR) strains. We present here the first map of a Ti plasmid from a WHR o/c strain, Tm4. pTiTm4 (252 kb) has homology with the octopine Ti plasmid pTiAch5, the nopaline plasmid pTiC58, and the Ri plasmid pRiHRI. Approximately 155 kb of pTiTm4 is homologous with the LHR o/c Ti plasmids pTiAB3 and pTiAg57, the remaining part is pTiTm4-specific. Our data suggest that the evolution of the o/c Ti plasmids was accompanied by large-scale changes in plasmid structure. The origin of replication of pTiTm4 was localized by a functional assay.