Cemagref : Individual report

Cemagref carried out many experiments in 1994, within the European project, on Douglas-fir and Norway spruce cuttings associated with Laccaria bicolor S238N and, in some cases, with Pseudomonas fluorescens. Three trials were set up in greenhouses (task C) in relation with the rooting phase. Five experiments were conducted in nursery beds, and two were established in field trials to study the effectiveness of mycorrhizal short root colonisation and also the growth and survival performance of mycorrhizal cuttings (task D). The first outcomes showed that inoculation during the rooting phase is not successful. On the contrary, inoculation of the rooted cuttings in fumigated transplant beds is effective: it led to a high root colonisation by the inoculated fungal strain and, quite often, the growth performance was enhanced. After planting, the first-year height growth and the survival rate varied very little between treatments. Nevertheless, at Vidaillat, a positive effect of inoculation was observed for the first time on second-year height growth.