Data from: Wood-inhabiting insects can function as targeted vectors for decomposer fungi

Most wood-inhabiting fungi are assumed to be dispersed primarily by wind, with the exception of a few species involved in mutualistic relationships with insects. In this study we tested whether several species of wood-inhabiting insects can function as dispersal vectors for non-mutualistic fungi, which would indicate that wood-inhabiting fungi can benefit from targeted animal-mediated dispersal. We sampled wood-inhabiting beetles (Coleoptera) from freshly felled wood experimentally added to forests and used DNA metabarcoding to investigate the fungal DNA carried by these insects. Staphylinid beetles rarely contained fungal DNA, while Endomychus coccineus, Glischrochilus hortensis and Glischrochilus quadripunctatus frequently carried fungal DNA with a composition specific to the insect taxon. A large proportion of the obtained fungal sequences (34%) represented decomposer fungi, including well-known wood-decay fungi such as Fomitopsis pinicola, Fomes fomentarius, Trichaptum abietinum and Trametes versicolor. Scanning electron microscopy further showed that some of the fungal material was carried as spores or yeast cells on the insect exoskeletons. Our results suggest that insect-vectored dispersal is of broader importance to wood-inhabiting fungi than previously assumed.

多数木栖真菌被认为主要依靠风力传播，仅少数与昆虫形成互利共生关系的类群除外。本研究旨在探究多种木栖昆虫是否可作为非互利共生真菌的传播媒介，以此验证木栖真菌能否通过靶向性的动物介导传播获得生存优势。我们从人工布设至林内的新鲜伐倒木中采集木栖甲虫（鞘翅目Coleoptera），并借助DNA宏条形码（DNA metabarcoding）技术检测这些昆虫携带的真菌DNA。结果显示，隐翅甲科甲虫体内极少检出真菌DNA，而红皮囊甲（Endomychus coccineus）、苹果露尾甲（Glischrochilus hortensis）和四斑露尾甲（Glischrochilus quadripunctatus）则常携带真菌DNA，且真菌群落组成与昆虫类群具有特异性关联。本次检测获得的真菌序列中，有34%属于分解真菌类群，其中包括多种知名木材腐朽真菌，如松生拟层孔菌（Fomitopsis pinicola）、木蹄层孔菌（Fomes fomentarius）、冷杉附毛孔菌（Trichaptum abietinum）以及彩绒革盖菌（Trametes versicolor）。扫描电子显微镜（Scanning electron microscopy）进一步观测发现，部分真菌以孢子或酵母细胞的形式附着于昆虫外骨骼表面。本研究结果证实，昆虫介导的传播对木栖真菌的重要性远超此前的学术认知。