ORIGINAL PAPER Seasonal dynamics of Boletus edulis and Lactarius deliciosus extraradical mycelium in pine forests of central Spain Herminia De la Varga & Beatriz Águeda & Teresa Ágreda & Fernando Martínez-Peña & Javier Parladé & Joan Pera Received: 23 July 2012 / Accepted: 24 January 2013 / Published online: 8 February 2013 # Springer-Verlag Berlin Heidelberg 2013 Abstract The annual belowground dynamics of extraradi- cal soil mycelium and sporocarp production of two ectomy- corrhizal fungi, Boletus edulis and Lactarius deliciosus, have been studied in two different pine forests (Pinar Grande and Pinares Llanos, respectively) in Soria (central Spain). Soil samples (five per plot) were taken monthly (from September 2009 to August 2010 in Pinar Grande and from September 2010 to September 2011 in Pinares Llanos) in eight permanent plots (four for each site). B. edulis and L. deliciosus extraradical soil mycelium was quantified by real-time polymerase chain reaction, with DNA extracted from soil samples, using specific primers and TaqMan® probes. The quantities of B. edulis soil my- celium did not differ significantly between plots, but there was a significant difference over time with a maximum in February (0.1576 mg mycelium/g soil) and a minimum in October (0.0170 mg mycelium/g soil). For L. deliciosus, significant differences were detected between plots and over time. The highest amount of mycelium was found in De- cember (1.84 mg mycelium/g soil) and the minimum in February (0.0332 mg mycelium/g soil). B. edulis mycelium quantities were positively correlated with precipitation of the current month and negatively correlated with the mean temperature of the previous month. Mycelium biomass of L. deliciosus was positively correlated with relative humidity and negatively correlated with mean temperature and radia- tion. No significant correlation between productivity of the plots with the soil mycelium biomass was observed for any of the two species. No correlations were found between B. edulis sporocarp production and weather parameters. Spo- rocarp production of L. deliciosus was positively correlated with precipitation and relative humidity and negatively cor- related with maximum and minimum temperatures. Both species have similar distribution over time, presenting an annual dynamics characterized by a seasonal variability, with a clear increase on the amounts of biomass during the coldest months of the year. Soil mycelial dynamics of both species are strongly dependent on the weather. Keywords Boletus edulis . Lactarius deliciosus . Soil mycelium . Real-time PCR . Climate . Mushroom productivity Introduction Boletus edulis Bull. and Lactarius deliciosus Fr. are valued wild edible fungi, gastronomically appreciated and sold in local markets of many countries, particularly in Europe. These mushrooms are collected from the wild, and in some geographic areas, its trade has become an important eco- nomic income, as valuable nonwood forest products (Boa 2004). B. edulis and L. deliciosus are symbiotic fungi which form ectomycorrhizal associations with the roots of trees H. De la Varga (*) : J. Parladé : J. Pera IRTA, Sustainable Plant Protection, Centre de Cabrils, Ctra. de Cabrils, Km 2, 08348 Cabrils, Barcelona, Spain e-mail: hermivp@gmail.com B. Águeda : T. Ágreda : F. Martínez-Peña Centro de Investigación Forestal de Valonsadero, Consejería de Fomento y Medio Ambiente, Junta de Castilla y León, Apdo. Correos 175, 42080 Soria, Spain Mycorrhiza (2013) 23:391–402 DOI 10.1007/s00572-013-0481-3