New data concerning the evolution of the vegetation in Lillo pinewood (Leon, Spain)

A pollen study of a peat-bog sited in the pinewood of Lillo (León, Spain) is presented. The diagram shows an initial phase where a well-developed pinewood was dominant with deciduous species, followed by a selective clearance process of Pinus . Finally, the pinewood recovers again towards a similar state to that described at the beginning of the profile. Radiocarbon dates point that the timing of peat formation took place around 1720±60 years bp and the deforestation on 780±80 years bp . The results have allowed to explain the autochthonous character of Lillo pinewood, which remains as one of the few relics of the southern slopes of the Cantabrian Range.     

Pulsed-field electrophoresis in contour-clamped homogenous electric fields (CHEF) for fingerprinting of Rhizobium spp

Abstract: A pulsed-field gel electrophoretic method based on contour-clamped homogeneous electric field (CHEF) was developed for the analysis of natural isolates of Rhizobium leguminosarum biovar viciae . The procedure involves the use of 'rare-cutting' endonucleases. The separation of genomic DNA fragments with split runs ( τ = 5 s for 15 h followed by τ = 12 s for 9 h) allows a clear definition of profiles with bands ranging from 20–300-kb pairs. Two and a half days are sufficient to reproducibly accomplish the procedure from cell lysis to gel picture. The method can be used for different fast-growing rhizobia.