A B S T R A C TEuropean chestnut (Castanea sativa Mill.) trees have a significant impact in the Portuguese economy, due to the production of chestnuts and wood, and other related activities, such as mushroom collection and hunt. Hypholoma fasciculare (Huds.) is a saprophytic fungus widely distributed in Trás-os-Montes (northeast of Portugal) chestnut groves that displays an in vitro strong antagonistic activity against ectomycorrhizal (EMC) fungi. In this study, the above-and belowground fungal diversity was evaluated in three chestnut orchards, containing distinct H. fasciculare sporocarps abundances in an attempt to better understand the potential of this fungus to attain an improved chestnut tree sustainable productivity. Aboveground analysis was performed based on macrofungi collection during fruiting seasons (spring and autumn) of two consecutive years. Belowground evaluation was based on the metabarcoding of chestnut orchards soil DNA, using the fungal barcode ITS1 and a high-throughput sequencing (454-sequencing) approach. Although all collected fruitbodies were identified as being produced by Basidiomycota fungi, a more diversified fungal community was revealed by the belowground approach. Both approaches have revealed a rich and abundant ECM community in all chestnut orchards. The correlation between the abundance of H. fasciculare fruitbodies and specific fungal guilds fruitbodies/reads suggests that this fungus may affect soil fungal community, mainly ECM and phytoparasites, as well as species composition of fungal communities. Although not conclusive, the results suggest that H. fasciculare presence could be critical for sustainable chestnut ecosystems.Keywords: Castanea sativa, chestnut orchard soils, ectomycorrhizal community, Hypholoma fasciculare, ITS metabarcoding.
R E S U M OO castanheiro europeu (Castanea sativa Mill.) tem um enorme impacto na economia Portuguesa, sobretudo devido à produção de castanha e de madeira, mas também de actividades relacionadas com a colheira de cogumelos e a caça. Hypholoma fasciculare (Huds.) é um fungo saprófita amplamente distribuído nos soutos da região de Trás-os-Montes (nordeste de Portugal) e que apresenta, em condições in vitro, uma forte actividade antagonista contra fungos ectomicorrízicos. Neste estudo pretendeu-se avaliar a comunidade fúngica presente na superfície e no sub-solo de soutos contendo diferentes abundâncias de carpóforos de H. fasciculare, numa tentativa de compreender melhor a possibilidade deste fungo melhorar a produção sustentável do castanheiro. A diversidade fúngica à superfície do solo foi avaliada recorrendo à colheita de cogumelos durante o outono e a primavera, ao longo de dois anos consecutivos. A diversidade no sub-solo foi avaliada molecularmente pela extração do DNA do solo de soutos, amplificação da região ITS1 e sequenciação de nova geração (sequenciação 454). Apesar dos cogumelos colhidos serem todos produzidos por fungos Basidiomicetes, uma comunidade fúngica mais diversificada foi revelada pela abordagem molecular. No ent...