We report here the whole-genome sequence of Nostoc cycadae strain WK-1, which was isolated from cyanobacterial colonies growing in the coralloid roots of the gymnosperm Cycas revoluta It can provide valuable resources to study the mutualistic relationships and the syntrophic metabolisms between the cyanobacterial symbiont and the host plant, C. revoluta.

The carbon flux from woody debris, a crucial uncertainty within global carbon-climate models, is simultaneously affected by climate, site environment and species-based variation in wood quality. In the first global analysis attempting to explicitly tease out the wood quality contribution to decomposition, we found support for our hypothesis that, under a common climate, interspecific difference...

The Iberian Peninsula harbors about 50% of European plant and terrestrial vertebrate species and more than 30% of European endemic species. Despite the global recognition of its importance, the selection of protected areas has been ad hoc and the effectiveness of such choices has rarely been assessed. We compiled the most comprehensive distributional data set of Iberian terrestrial plant and ve...

The abrupt origin and rapid diversification of the flowering plants during the Cretaceous has long been considered an "abominable mystery." While the cause of their high diversity has been attributed largely to coevolution with pollinators and herbivores, their ability to outcompete the previously dominant ferns and gymnosperms has been the subject of many hypotheses. Common among these is that...

Inducible T-strand mobilization from the Ti plasmid of Agrobacterium tumefaciens to the genome of a plant host is mediated by the activation of a cascade of bacterial virulence genes. It is initiated when the bacterium senses the presence of a low molecular weight inducer secreted by the plant. Although many hydroxyphenylpropanoid and phenolic compounds can activate the virulence cascade, the o...

Mycorrhizal fungi constitute a key functional group of soil biota that greatly contribute to productivity and sustainability of terrestrial ecosystems. These are ubiquitous components of most of the ecosystems throughout the world and are considered key ecological factors in governing the cycles of major plant nutrients and in sustaining the vegetation cover (van der Hejden eta!. 1998; Requena ...

Cyanobacteria constitute one of the largest subgroups of Gram-negative photosynthetic prokaryotes and are of great evolutionary antiquity, dating back to the Precambrian (2.8–3.5 billion years ago). They are found worldwide in highly diverse ecosystems, from aquatic (limnic and marine) habitats to terrestrial systems and from polar to tropical regions of the globe. In terrestrial systems, nitro...

Tracheary element differentiation and secondary cell-wall formation have been studied in cell cultures of coniferous gymnosperms. Factors that influence tracheary element differentiation are (i) the sucrose concentration in the media, (ii) the concentration of nutrients in the media, (iii) temperature and light, and (iv) the types and concentrations of phytohormones in the media. There are adva...

Upper Westphalian coals are usually rich in organic-matter of different plant taxa, including gymnosperms. The assemblage from Kalinovo (Eastern Ukraine) is exceptional in being dominated by Sphenophyllum, both cuticles and conducting tissues. Sphenophyllum cuticles are easily distinguished by their parallel oriented cells with sinuous anticlinal walls, and paracytic stomata on the abaxial cuti...

Seventeen diterpenes belonging to the labdane, abietane and isopimarane skeleton classes were isolated from the resin of the Chilean gymnosperm Austrocedrus chilensis and identified by spectroscopic and spectrometric methods. The diterpene 12-oxo-labda-8(17),13E-dien-19 oic acid is reported for the first time as a natural product and 14 diterpenes are reported for the first time for the species.