Quantification of b. Edulis extraradical mycelium in the soilunder different C. Ladanifer management treatments

Resum

Cistus ladanifer scrublands host an extraordinary production of highly demanded edible fungi. Among those, the species belonging to the genus Boletus have the greatest interest in these otherwise non-productive ecosystem. Regarding Boletus edulis Bull., previous research has found that its fructification, quite variable among years, depends on several factors like the age of the stand, its density and climatic factors. There is nonetheless important missing information on the life cycle of this species, like the seasonal dynamics of B. edulis mycelium on the soil. Consequently, in this study we wondered about whether different management options couldenhance the presence of Boletus edulis mycelium in the soil and thus, the production of mushrooms. The treatments consisted of different levels of fuel reduction: 50% clearing, totalclearing and no clearing (control), established in scrublands of different age and origin. Soil samples were taken at three different times: at the end of the sporocarp fruiting season(December), in April and in July. DNA extractions were performed with the PowerSoil® DNA Isolation Kit and B. edulis DNA was amplified by real-time PCR using specific primers and Taqman probes. Our results confirmed the widespread presence of B. edulis mycelium in the soil and a significant influence of management and time over the quantities of B. edulis extraradical mycelium in the soil. We found the amount of mycelium in the soil to be highest where no clearing was done, although there were also significant concentrations in 50% clearing plots. Total clearing plots displayed low concentrations of mycelium. Regarding seasonal dynamics, we found that B. edulis mycelium was more abundant in December. Finally, we found that the correlation between mycelium in the soil during the fruiting season and mushroom production was higher than in either April or July. Based on these results, the most suitable management practises to enhance B. edulis production and ecosystem conservation will be proposed.