Pathogénie comparée de 4 espèces d'Helminthosporium Obtenues à Partir des Plantes Malades du Riz au Maroc

A comparative study into the pathogenicity of four Helminthosporiumspp. towards rice cultivars in Marocco In this paper, the behaviour of four Helminthosporium species on nine rice cultivars widely cultivated in Morocco, permit the classification of this species according to their virulence. Helminthosporium oryzae and Helminthosporium sativum are the most virulent and the best equipped to sporule on all varieties of tested lesions. The level of pathogenicity of Helminthosporium spiciferum and Helminthosporium australiensis and their capacity to sporule on host plant depend on the rice variety used. At the same time, each Helminthosporium induces characteristics symptoms on rice leaves.     

L'évolution parallèle des Juraphyllitidae euroboréaux et téthysiens au Pliensbachien: le rôle des contraintes internes et externes

Au Pliensbachien, un trend morphologique se developpe chez les Tragophyllocerassimpliquant un mécanisme hétérochronique (paedomorphose par néoténie) pour I'acquisition d'une morphologie suboxycône. Ce changement morphologique majeurest concomitant avecl'ingression de ces formes dans les mers de plateforme euroboréale ob la compétition inter-taxons est forte. Cette option morphofonctionnelle et évolutive, canalisée essentiellement par des contraintes externes étant amorcée, le genre va I'exploiter dans la mesure de ses possibilités (potentialités intrinsèques) en perfectionnant son oxycônie. Au contraire dans les mers téthysiennes, les Juraphyllites ne montrent pas d'évolution pour la morphologie de la coquille; celle-ci reste subplatycône durant tout le Lias moyen et il n'y a pas de changements environnementaux majeurs (milieux tamponnés). En outre la prolifération d'ornementations plus grossières, aussi bien chez les Juraphyllites que chez les Tragopbylloceras, correspond probablement à une meilleure exploitation des biomes d'Europe du NW et de la Téthys à une période bien précise qui est le Carixien moyen. Ce développement d'ornementation similaire chez des taxons partageant un héritage évolutif commun mais séparés paléogéographiquement, évoque le rôle prépondérant des contraintes internes. Ainsi l'évolution des Juraphyllites des Tragophyllocerasau Lias moyen paraît donc ètre un exemple de parallèlisme au sens strict du terme.□Évolution, hétérochronies, Juraphyllitidae, Lias, ontogenèse, Paléogéographie. A morphological trend in the Pliensbachian Tragophyllocerns involves a heterochronic process (paedomorphosis by neoteny) to acquire a suboxycone morphology. This major morphological change is concomitant with the ‘ingression’ of Tragophylloceras in the Euroboreal platform seas, where competition between taxa was strong. This functional-morphological and evolutionary option is mainly canalized by extrinsic constraints. Exploring these possibilities, Tragophylloceras then exploits and improves the oxycone option. By contrast, in the Tethyan seas, Juraphyllites shows no change in shell coiling; it stays subplatycone during all the Pliensbachian. There is no major environmental change. Moreover, the proliferation of coarser ornamentation in Juraphyllitesand Tragophylloceras probably corresponds to a better exploitation of the Euroboreal and Tethyan marine habitats during the Middle Carixian. The development of similar ornamentation in palaeogeographically separate taxa with a common evolutionary origin is mainly canalized by intrinsic constraints. The evolution of Juraphyllites and Tragophylloceras appears to be a good example of parallelism sensu stricto. □ Evolution, heterochrony, Juraphyllitidae, Lios, ontogeny, palaeogeography.     

Les statues-menhirs du Rouergue et du Haut-Languedoc : la posture des jambes et la technique de représentation des effigies féminines et masculines

Wex (1993) observes through the statuary of great historical cultures how body language appears to reflect the evolution of the respective status of man and woman. On the other hand, Serres (1997) reports that the feminine statues-menhirs of his so called groupe rouergat are represented with legs spread out, while masculine statues show broad as well as narrow postures. We examined this observation more systematically and further applied to it the properly ethological reading grid of Wex as a contribution to the history of gender relationships. A preliminary quantitative analysis aimed to determine which attributes give certainty about the sexual identity of the statues-menhirs. Special attention is given to the figures who underwent a gender change.     

Etude Ultrastructurale des Mérozoites et de la Schizogonie des Coccidies (Eimeriina): Eimeria magna (Perard 1925) de I'Intestin des Lapins et E. tenella (Railliet et Lucet, 1891) des Coecums des Poulets

SYNOPSIS. An electron microscopic study is made of merozoites and schizogony of Eimeria magna and Eimeria tenella from rabbits and chickens infected 5 days before fixation.
The merozoite outer layer is formed by a unit membrane lined by a dense osmiophilic layer. A micropyle is present. The apical complex of the cell is constituted by a conoid surmounted by 2 rings and surrounded by another from which about 26 subpellicular, tubular fibrils start. Two "rhoptries" (= toxonemes) go thru the conoid to the apex of cell. Rare sarconemes (= convoluted tubes) are disseminated in the anterior part of merozoites. A nucleus with nucleolus, Golgi apparatus, mitochondria, endoplasmic reticulum, lipid globules and glucidic grains were observed.
Schizogony starts by the formation of a multinucleated schizont which has a centriolar structure. The new merozoites appear as evaginations of the schizont's membrane. Cellular organelles (conoid, rhoptries, micropyle, sarconemes) differentiate and the nuclei enter the diverticula of the schizont. Then the development of merozoites proceeds by "external budding".
The ultrastructural similarities between the merozoites of Eimeria and the endodyocytes of Toxoplasmea, appear to us to be extremely interesting and indicate a close relationship between the Toxoplasmea and the Coccidia.     

Sur les familles des Helicancylidae Hyatt, 1894 et des Acrioceratidae Vermeulen, 2004 ; réponses et précisions apportées au travail de Bert, 2009

This work is mainly an answer to the work of Bert (2009), on families Helicancylidae Hyatt, 1894 and Acrioceratidae Vermeulen, 2009. On the nomenclatural speaking, the non validity of the genus Helicancylus Gabb, 1869 and of the family Helicancylidae Hyatt, 1894 and, consequently, the validity of the family Acrioceratidae Vermeulen, 2004 are established. The second part of this work is devoted to the respect of former work and, contrary to the assertions from Bert (2009), it is shown that the stratigraphical positioning of the Upper Barremian level with small Barremites, realized by Cotillon (1971), is at least as precise as that proposed by Bert. The last part of this work highlights a lack of bibliographical references, fact which had already been highlighted ( Vermeulen and Lepinay, 2010) in a former work of Bert et al. (2009).     

Stratigraphie, paléoécologie et foraminifères du paléogène des Alpes Maritimes et des Alpes de Haute-Provence (Sud-Est de la France)

Paleogene sedimentation in the Alpes Maritimes and Alpes de Haute Provence regions is composed of one complete sedimentary sequence. This sequence begins with the continental Formation from Microcodium and continues with the Cerithium layers, the Calcaires Nummulitiques and the Marnes Bleues, which are overlaid by the turbidites of the Grès d’Annot Formation. Sedimentation starts in the Nummulites perforatus zone close to the base of ‘the Truncorotaloides rohri zone (P 14) and ends in the Cassigerinella chipolensis-Pseudohastigerina micra zone (P 18) and the NP21 zone in the upper part of the Grès d’Annot. More biomarkers were used in order to define a more detailed local biozonation (biozones AMP 1 to AMP 7). Four local zones were also defined by the last occurrence of Nummulites millecaput and N. perforatus-N. ptukhiani and then by the first appearance of N. retiatus (AMGF 1-4). The evolution of benthic foraminiferal assemblages shows an increase in bathymetry from the internal platform in the Cerithium layers to the calcareous platform with large foraminifers, then to the external platform and the deep offshore environment of the Marnes Bleues and Grès d’Annot. Low faunal diversity in the Grès d’Annot together with the predominance of agglutinated species indicates a poorly oxygenated, organic rich and turbidite environment. Seven steps (SD 1 to SD 7) in the Eocene marine transgression are shown from East to West by detailed local biozonation and sequence analysis. Grès d’Annot sedimentation is also diachronous, beginning within the Truncorotaloides rohri zone (P 14, AMP 1) in the East and ending within the Pararotalia opima opima zone (P 20, middle Rupelian) in the West (Barrême). Small foraminifer Paleogene fauna from the Alpes Maritimes and Alpes de Haute Provence was studied from 400 samples. It is composed of 378 species. Two new taxa are proposed: Fissurina niceana n. sp. and Globocassidulina alpina n. sp. The species from the Escarène and Gorbio neighborhood described by M. von Hantken (1884) were re-examined.     

L’ambre cénomanien d’Anjou : stratigraphie et paléontologie des carrières du Brouillard et de Hucheloup (Ecouflant,Maine-et-Loire)

The Ecouflant area (Maine-et-Loire, France) shows the last outcrops from the Anjou region that allow the study of early Cenomanian lignites and the associated amber. The quarry of Le Brouillard was historically the most studied locality, but it is now partly covered by bulky waste. No fossil arthropod has been found in the amber collected in this locality, and only a few bacterial filaments and plant fragments were detected among the microinclusions. The quarry of Hucheloup shows a wider exposure. Amber is poor, but fossil plants and bivalve are frequent. Based on the sedimentological series and the palaeontological contents of the lignitic clay, we suggest that it corresponds to estuarine to coastal depositional environments with variable salinity.     

L'Ichthyofaune des marnes messiniennes des environs de senigallia (Marche,Italie): Signification paleoecologique et paleogeographique

The revision of the fish fauna from the Messinian marls of Senigallia (Marche, Italy) leads to the reduction of the faunal list of the fossil Fishes found in this locality to only four species. One new genus is created: Cryptolebias new. gen.. This fish fauna characterizes an environment with a variable salt content: it may have been more or less temporarily connected with the sea, although it was also exposed to noticeable continental influences, as demonstrated by the occurrence of Amphibians and Reptiles (Ophidians).