The process of fungal community succession in forests is still insufficiently known, especially in Mediterranean ecosystems. To reveal successional patterns, we studied changes in aboveground sporocarp composition in managed Pinus pinaster Ait. forests across a stand age chronosequence from 5 to more than 90 years in Soria province (Central Spain). We evaluated the effect of yearly conditions and stand age on species richness, composition, and trophic groups. All aboveground sporocarps were collected and identified in 21 plots, each measuring 150 m 2 , placed in a random stand agestratified survey. Sampling was performed weekly in the autumn during 6 years (1997)(1998)(1999)(2000)(2001)(2002). The effect of year and stand age on species richness was analysed using repeated measures analysis of variance and change in composition. Changes in community composition were evaluated via canonical correspondence analysis (CCA). The response of different trophic groups was analyzed using ANOVA with age as a fixed factor. Fungal community richness increased with stand age. This increase was related to the rise in humicolous saprotroph and mycorrhizal species. The presence of parasitic and lignicolous fungi was always very low, probably as a result of forest management. Yearly conditions exerted a stronger effect than stand age on aboveground sporocarp community richness and composition.Résumé : On connaît peu le processus de succession des communautés fongiques dans les forêts, surtout dans les écosys-tèmes méditerranéens. Afin de déceler les patrons de succession, les auteurs ont étudié les changements de la composition en sporocarpes épigés, dans des forêts aménagées de Pinus pinaster Ait., selon une chronoséquence d'âges, allant de 5 à 90 ans, dans la province de Soria (centre de l'Espagne). On a évalué l'effet des conditions annuelles et l'âge du peuplement sur la richesse en espèces et les groupes trophiques. Les auteurs ont récolté et identifié tous les sporocarpes dans 21 parcelles mesurant 150 m 2 , dans un suivi aléatoire des peuplements par strates d'âges. On a conduit un échantillonnage hebdomadaire au cours de l'automne de 6 années consécutives (1997)(1998)(1999)(2000)(2001)(2002), et analysé l'effet de l'année et de la classe d'âge sur la richesse en espèces, en utilisant l'analyse de variance par mesures répétées, ainsi que sur le changement de la composition. On a évalué les changements de composition des communautés avec CCA et la réaction des différents groupes trophiques avec ANOVA, l'âge étant le facteur fixe. La richesse de la communauté fongique augmente avec l'âge du peuplement. Cette augmentation est reliée à une augmentation des espèces saprotrophes humicoles et mycorhiziennes. La présence de champignons parasites et lignicoles est toujours faible, une conséquence probable de l'aménagement forestier. Les conditions annuelles exercent un effet plus important que l'âge du peuplement sur la richesse et la composition des communautés de sporocarpes épigés.

Wild fungi play a critical role in forest ecosystems, and its recollection is a relevant economic activity. Understanding fungal response to climate is necessary in order to predict future fungal production in Mediterranean forests under climate change scenarios. We used a 15-year data set to model the relationship between climate and epigeous fungal abundance and productivity, for mycorrhizal and saprotrophic guilds in a Mediterranean pine forest. The obtained models were used to predict fungal productivity for the 2021-2080 period by means of regional climate change models. Simple models based on early spring temperature and summer-autumn rainfall could provide accurate estimates for fungal abundance and productivity. Models including rainfall and climatic water balance showed similar results and explanatory power for the analyzed 15-year period. However, their predictions for the 2021-2080 period diverged. Rainfall-based models predicted a maintenance of fungal yield, whereas water balance-based models predicted a steady decrease of fungal productivity under a global warming scenario. Under Mediterranean conditions fungi responded to weather conditions in two distinct periods: early spring and late summer-autumn, suggesting a bimodal pattern of growth. Saprotrophic and mycorrhizal fungi showed differences in the climatic control. Increased atmospheric evaporative demand due to global warming might lead to a drop in fungal yields during the 21st century.

With the aim of increasing knowledge of community structure, dynamics and production of ectomycorrhizal fungi, edible sporocarp yields were monitored between 1995 and 2004 in a Pinus sylvestris stand in the northeast zone of the Iberian Peninsula. A random sampling design was performed by stand age class according to the forest management plan: 0-15, 16-30, 31-50, 51-70 and over 71-years-old. Eighteen 150 m plots were established and sampled weekly every year from September to December. One hundred and nineteen taxa belonging to 51 genera were collected, 40 of which were edible and represented 74% of the total biomass. Boletus edulis, Lactarius deliciosus, Cantharellus cibarius and Tricholoma portentosum sporocarps, which are considered to be of high commercial value, represented 34% of the total production. B. edulis and L. deliciosus were the most remarkable and abundant species, and both were collected in more than 60% of the samplings. B. edulis fructified every year of the experiment; its mean production was 40 kg/ha and year and its maximum productivity was more than 94 kg/ha in 1998. The age class with the largest production of this taxa was the fourth (51-70 years), with 70 kg/ha. L. deliciosus only failed to fructify one autumn (2000); its mean production was almost 10 kg/ha and its maximum productivity close to 30 kg/ha in 1997. The maximum productivity of this species was found in the second (16-30 years) and fifth (71-90 years) stand age classes, with 18 and 16 kg/ha, respectively. Advances in this field can certainly offer new insights into factors affecting sporocarp production.

Ectomycorrhizas of Boletus aereus, Boletus edulis, and Boletus reticulatus were synthesized with Cistus sp. under laboratory conditions using synthesis tubes filled with a mixture of sterilized peat-vermiculite and nutrient solution. The fungal strains isolated from sporocarps were identified by molecular techniques. The inoculated seedlings were grown for 4-5 months. The ectomycorrhizas formed were described based on standard morphological and anatomical characters. The three ectomycorrhizas described were very similar, with white monopodial-pinnate morphology, a three-layered plectenchymatous mantle on plan view and boletoid rhizomorphs.

Lack of information and difficulty in predicting wild edible sporocarp yields is blocking its integration in forest management. In the Mediterranean area, this nontimber forest product has increased its market value, consumption demand, and interest over the last decade. In this work, sampling year and stand age effects are analyzed in order to advance knowledge of edible fungi community structure, dynamics, and production. Weekly autumnal sporocarp monitoring was performed from 1997 to 2011 in a Pinus pinaster managed forest in central Spain. After applying a random stand age-stratified survey, 21 plots of 150 m(2) have been set with three per stand age class. The forest age classes have been defined as follows: 0-10 years, mixture of parent and regenerated trees, 11-20, 21-40, 41-60, 61-90, and over 90 years. A total of 153 species belonging to 56 genera were recorded, 55 of which are edible. The production of edible sporocarps was 19.8 kg ha(-1), representing 31 % of total production. Sporocarp production presents a sharp interannual variability with autumns 62 times more productive than others. The most abundant edible species in terms of fresh weight per hectare has been Lactarius deliciosus with 7.0 kg ha(-1). Edible fungi yields registered a significant decline in 10 years following regenerative cutting. The presence of parent trees significantly increases production with regard to the first class. The highest production of edible species occurs in the middle age, 41-60 years, and in the following classes, a decrease is produced. L. deliciosus production registered differences with age, manifesting in a high yield in young stands (11-20 years) and significant recovery in woodlands near to the cutting.

The study of factors influencing the production and development of wild edible mushroom sporocarps is extremely important in the characterization of the fungi life cycle. The main objective of this work is to determine how tree age influences the speed of sporocarp growth of edible ectomycorrhizal fungi Boletus edulis and Lactarius deliciosus in a Pinus sylvestris stand. This study is based on information recorded on a weekly basis every autumn between 1995 and 2008 in a set of permanent plots in Spain. Sporocarps are collected weekly, and as a result, specimens may not have reached their maximum size. The study area is a monospecific P. sylvestris stand. Three age classes were considered: under 30 years, between 31 and 70 years, and over 70 years. Sporocarps of B. edulis and L. deliciosus grow faster in the first age class stands than in the other two, and in the second age class stands, sporocarps are more than 50% smaller. The average weight of the picked B. edulis sporocarps clearly varies in the three age classes considered, with its maximum in the first age class (127 g and 6.8 cm cap diameter), minimum in the second age class (68 g and 4.7 cm cap diameter), and showing a relative maximum in the third (79 and 4.3 cm cap diameter). L. deliciosus sporocarps are on average larger in the first age class (48 g and 7.4 cm cap diameter), decreasing in the second (20 g and 5.8 cm cap diameter) and also in the third (21 g and 5.3 cm cap diameter). The results show the influence of tree age in speed of sporocarp growth for the two ectomycorrhizal species.

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