We measured the cytonuclear disequilibrium between 11 nuclear allozyme loci and both mitochondrial and chloroplast DNA haplotypes in a natural population of ponderosa pine (Pinus ponderosa, Laws). Three allozyme loci showed significant associations with mtDNA variation, while two other loci showed significant association with cpDNA. However, the absolute number of individuals involved in any of...

Repeated grafting of shoot apices from mature Sequoia sempervirens (D. Don) Endl. trees onto young seedling shoots in vitro causes emergence of rejuvenated, or phase-reversed, scion shoots. The phase reversal is indicated by a restored rooting competence and renewed vigor of roots and shoots. We earlier reported of restriction fragment length polymorphism between juvenile or rejuvenated and adu...

The taxonomy and phylogeny of Asian Meconopsis (Himalayan blue poppy) remain largely unresolved. We used the internal transcribed spacer (ITS) region of nuclear ribosomal DNA (nrDNA) and the chloroplast DNA (cpDNA) trnL-F region for phylogenetic reconstruction of Meconopsis and its close relatives Papaver, Roemeria, and Stylomecon. We identified five main clades, which were well-supported in th...

Genetic structure and seed Germination in PortuGuese PoPulations of Cheirolophus uliginosus (asteraceae): imPlications for conservation strateGies.— Cheirolophus uliginosus is a threatened species, endemic to the Atlantic coast of the Iberian Peninsula, where it occupies a few restricted localities. In our study we analysed the patterns of cpDNA haplotypes variation and reproductive success—ger...

Draba ladina (Brassicaceae) is a small alpine flower endemic to the Swiss Alps. It occurs exclusively at elevations between 2600 and 3000 m and is restricted to less than a dozen mountains in the Lower Engadin. Morphological characters and polyploidy suggest a hybrid origin. Potential diploid progenitor species are distributed widely and often occur sympatrically. To study the evolutionary hist...

The cotton genus (Gossypium spp.) contains 8 monophyletic diploid genome groups (A, B, C, D, E, F, G, K) and a single allotetraploid clade (AD). To gain insight into the phylogeny of Gossypium and molecular evolution of the chloroplast genome in this group, we performed a comparative analysis of 19 Gossypium chloroplast genomes, six reported here for the first time. Nucleotide distance in non-c...

The general phylogeographical paradigm for eastern North America (ENA) is that many plant and animal species retreated into southern refugia during the last glacial period, then expanded northward after the last glacial maximum (LGM). However, some taxa of the Gulf and Atlantic Coastal Plain (GACP) demonstrate complex yet recurrent distributional patterns that cannot be explained by this model....

The complete nucleotide sequence of the plastid genome of the haptophyte Emiliania huxleyi has been determined. E. huxleyi is the most abundant coccolithophorid and has a key role in the carbon cycle. It is also implicated in the production of dimethylsulphide (DMS), which is involved in cloud nucleation and may affect the global climate. Here, we report the plastid genome sequence of this ecol...