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Palynological analysis of the genus Mertensia Roth, s. lat. (Boraginaceae) was performed. All pollen grains studied were mostly dumbbell shaped and had 6-heteroaperturate pollen type without exception. The type of pollen of Mertensia does not contradict recent classifications that assign Mertensia to Cynoglosseae. Among six sections of Mertensia, pollen grains of section Oreocharis (the Himalayan Mertensia) were different from those of other sections in having granulate sculpturing on the colpus and pseudocolpus membranes. The results, along with other morphological differences, may support Riedl's treatment of the Himalayan species of Mertensia in the distinct genus Pseudomertensia Riedl. Of the other sections, four monotypic sections (sections Steenhanmera, Neuranthia, Typomertensia, and Mertensianthe) showed pollen structures similar to each other. Pollen grains in section Eumertensia had some variations in size and ornamentation, especially in the species distributed in western North America. Key words: Boraginaceae, Mertensia, palynology, pollen grains, Pseudomertensia, taxonomy. Les auteurs ont effectue une analyse palynologique du genre Mertensisa Roth, s. lat. (Boraginaceae). Tous les grains de pollen etudies montrent generalement une forme d' haltere avec un type de pollen a 6 heteroapertures, sans exception. Le type de pollen ne s'oppose pas a la recente classification assignant les Mertensia aux Cyboglosseae. Au sein des six sections de Mertensis, les grains de pollen de la section Oreocharis (Mertensia de l'Himalaya) different de ceux des autres sections par leur patron granulaire sur les membranes des colpi et pseudocolpi. Les resultats, tout comme les autres differences morphologiques, pourraient supporter le traitement de Rield placant les especes de Mertensia de l'Himalaya dans un genre distinct, les Peudomertensia Riedl. Parmi les autres sections, quatre sections monotypiques (sections Steenhanmera, Neuranthia, Typomertensia,etMertensianthe) montrent des structures polliniques similaires les unes aux autres. Les grains de pollen de la section Eumertensia montrent quelques variations en grosseur et ornementations, surtout chez les especes de l'Ouest nord-americain. Mots-cles : Boraginaceae, Mertensia, palynologie, grains de pollen, Pseudomertensia, taxonomie. [Traduit par la Redaction], Introduction The genus Mertensia (Boraginaceae) comprises about 45 species distributed throughout temperate regions in the Northern Hemisphere (Mabberley 2008). Mertensia has been assigned to subfamily Boraginoideae (Johnston 1924; Al-Shehbaz 1991) [...]

* Premise of the study: Genetic and chromosomal variations in plants are often reflected in the geographical distribution patterns. Therefore, identifying such phylogeographical patterns on population is important for understanding the process of plant diversification and speciation, and analyzing both molecular and cytological aspects is necessary. * Methods: We investigated the phylogeographic pattern and genetic diversity of the widespread Japanese sedge, Carex conica complex, based on chloroplast DNA haplotypes and chromosomal variations. * Key results: Sixteen distinct haplotypes were detected from 258 individuals in the C. conica complex inferred from the cpDNA sequences of intergenic spacer (IGS) between atpB and rbcL, IGS between trnT and trnL, trnL intron, and IGS between trnL and trnF. Most haplotypes showed distinct geographical structures. Phylogenetic analyses revealed two major clades, clades 1 and II, among 16 haplotypes of the complex. The haplotypes of clade I were mainly found in eastern Japan, while most haplotypes of clade II were found in western Japan. Four intraspecific aneuploids of 2n = 32, 34, 36, and 38, with forming normal bivalents in meiotic divisions, were also found in the complex. The geographical distribution of these intraspecific aneuploids corresponded well with those of the haplotypes. * Conclusions: Our results suggest that the genetic diversity and chromosomal variations in the C. conica complex may have originated from contractions and expansions of geographical ranges affected by Quaternary climatic oscillations. Key words: aneuploidy; atpB-rbcL; Carex conica; chromosome number; cpDNA; Cyperaceae; trnT-trnL-trnF. doi: 10.3732/ajb.0900338

Product analyses and nanosecond time-resolved spectroscopy on laser flash photolysis are analyzed for the photoinduced electron-transfer reaction of 3,4-di([alpha]-styryl)furan. A new method is provided for the generation of aryl-substituted tetramethyleneethane (TME)-type intermediates.

The results of an investigation of the thermoluminescence and electroluminescence of arylated methylenecyclopropanes 1 are described. The mechanistic features of this reaction system have the potential of overcoming significant problems associated with organic light emitting diodes.