Le niébé (Vigna unguiculata [L.] Walp.) est l’une des principales cultures du bassin arachidier sénégalais. Il joue un rôle important dans les programmes de sécurité alimentaire et stratégies développement socio-économique pays. Toutefois, plusieurs contraintes (maladies, ravageurs, pression adventices, etc.) entraînent baisses rendements cette spéculation. donc important, trouver solutions adé...

Analysis of charcoal particles preserved in lake sediments has been frequently used to reconstruct fire, vegetation and climate history. Larger macroscopic (>125 μm) are attributed local fires, whereas microscopic (<125 μm), observed on pollen slides, a signal regional fire. Taxonomic identification the adds fire-history reconstruction by providing information about fuel composition past fire c...

Comprising ca. 28,000, species the Orchidaceae constitute one of most species-rich plant families. Orchids differ from other monocotyledons i.a., in formation so-called pollinaria, which are entities consisting pollen grains aggregated into compact pollinia and accessory structures, a viscidium mostly also pollinium stalk. The releases an adhesive material that attaches pollinarium to pollinato...

The Haemodoraceae is a relatively small family of monocotyledons. The most recent treatment by GEERINCK (1969) circumscribed the family as composed of rhizomatous, often sto loniferou s, scapose to subscapose herbs with basal, equitant, "Iris-like" leaves which are basally sheathing and distally unifacial by longitudinal folding and fusion. The inflorescence is terminal and usually branched and...

BACKGROUND The internal transcribed spacer 2 (ITS2) region of nuclear ribosomal DNA is regarded as one of the candidate DNA barcodes because it possesses a number of valuable characteristics, such as the availability of conserved regions for designing universal primers, the ease of its amplification, and sufficient variability to distinguish even closely related species. However, a general anal...

1. Cell-free extracts of all plants tested contained a novel enzyme activity (xyloglucan endotransglycosylase, XET) able to transfer a high-Mr portion from a donor xyloglucan to a suitable acceptor such as a xyloglucan-derived nonasaccharide (Glc4Xyl3GalFuc; XG9). 2. A simple assay for the enzyme, using [3H]XG9 and based on the ability of the [3H]polysaccharide product to bind to filter paper, ...

Self-incompatibility (SI) is found in approximately 40% of flowering plant species and at least 100 families. Although orchids belong to the largest angiosperm family, only 10% of orchid species present SI and have gametophytic SI (GSI). Furthermore, a majority (72%) of Dendrobium species, which constitute one of the largest Orchidaceae genera, show SI and have GSI. However, nothing is known ab...

Acetyl-coenzyme A (CoA) is used in the cytosol of plant cells for the synthesis of a diverse set of phytochemicals including waxes, isoprenoids, stilbenes, and flavonoids. The source of cytosolic acetyl-CoA is unclear. We identified two Arabidopsis cDNAs that encode proteins similar to the amino and carboxy portions of human ATP-citrate lyase (ACL). Coexpression of these cDNAs in yeast (Sacchar...

The systematic position of the river-weed family Podostemaceae remains enigmatic due to taxonomic difficulties imposed by the radically altered morphology of these alga-like angiosperms. Although previous workers have placed this group phylogenetically among a wide variety of monocotyledons and dicotyledons, most contemporary authors have proposed that fiver-weeds are closely related to members...

Phosphate homeostasis was studied in a monocotyledonous model plant through the characterization of the PHO1 gene family in rice (Oryza sativa). Bioinformatics and phylogenetic analysis showed that the rice genome has three PHO1 homologs, which cluster with the Arabidopsis (Arabidopsis thaliana) AtPHO1 and AtPHO1;H1, the only two genes known to be involved in root-to-shoot transfer of phosphate...