Diversity and fruiting pattern of macrofungi associated with chestnut (Castanea sativa) in the Trás-os-Montes region (Northeast Portugal)

The chestnut (Castanea sativa) agro-ecosystem is of great social, economic and landscape importance in NE Portugal. There are multiple resources associated with this crop, among them fruit and wood production and mushroom harvesting. However, information about the diversity and ecology of macrofungi is very scarce. In this context, the aim of this study was to assess the macrofungal diversity associated with chestnut trees over 4 y. Carpophore surveys were conducted in a non-tilled C. sativa orchard located in Bragança, Portugal, from Sep. 2002 to Dec. 2005. A total of 2677 carpophores belonging to 73 species across 16 families and 23 genera were recorded. Of the total number of macrofungal species listed, 82 % were ectomycorrhizal (EM) species. The genera with the greatest species richness were Russula, Inocybe and Lactarius, which accounted for 38.4 % of all species collected. The most abundant species were Laccaria laccata, Hebeloma crustuliniforme and Inocybe geophylla, which produced around 35 % of all carpophores. The cumulative number of species over the four successive years revealed that 80.5 % of macrofungal species that potentially exist in the study area were surveyed. Species richness and carpophore abundance fluctuated across years, which could have been related to weather conditions, especially to rainfall. Fructification occurred in two distinct seasons a year, autumn and spring, the first one being the most important in terms of number of species and carpophores. These data could be an important contribution toward the development of sustainable management practices for chestnut agro-ecosystem conservation.