Shino Ryotaro, Sotome Kozue, Endo Naoki, Maekawa Nitaro, Nakagiri Akira
a The United Graduate School of Agricultural Sciences, Tottori University.
b Fungus/Mushroom Resource and Research Center (FMRC), Faculty of Agriculture, Tottori University.
Mycoscience. 2023 Nov 20;64(6):136-149. doi: 10.47371/mycosci.2023.09.002. eCollection 2024.
, a genus in , , is a versatile fungus that lives as a wood decomposer, a potential pathogen of standing trees, and an orchid mycobiont. We previously reported that some species inhabiting wet wood in aquatic environments such as streams and waterfalls form synnema-like structures (SSs) bearing acanthophyses at their apices, and that they produce acanthophyses on vegetative hyphae when cultured on agar media. In this study, we investigated the acanthophysis-forming ability in and allied genera, and experimentally demonstrated the function of SSs. Phylogenetic analyses and observations of , and cultures showed that all of the strains forming acanthophyses belonged to , whereas strains of and did not produce acanthophyses. These findings suggest that SS/acanthophysis formation is a useful taxonomic character for members of . When strains were cultured under oxygen (O) concentrations of 5, 10, 20 and 40%, most of those cultured under 20% O formed the most acanthophyses. According to these experimental data, the SSs/acanthophyses in were considered to have a respiratory function. probably acquired the SS/acanthophysis-forming ability to adapt to moist and/or aquatic habitats and to decay wet wood in which the O concentration is often low.
[该属真菌] 是[某分类单元]中的一个属，是一种多功能真菌，可作为木材分解者生存，是立木的潜在病原体，也是兰花的菌根共生体。我们之前报道过，一些生活在溪流和瀑布等水生环境中的湿木上的[该属真菌]物种会形成顶端带有棘状附属物的似束丝结构（SSs），并且在琼脂培养基上培养时，它们在营养菌丝上也会产生棘状附属物。在本研究中，我们调查了[该属真菌]及其相关属中形成棘状附属物的能力，并通过实验证明了SSs的功能。对[该属真菌]、[另一属真菌]和[又一属真菌]培养物的系统发育分析和观察表明，所有形成棘状附属物的菌株都属于[该属真菌]，而[另一属真菌]和[又一属真菌]的菌株不产生棘状附属物。这些发现表明，SS/棘状附属物的形成是[该属真菌]成员的一个有用的分类特征。当[该属真菌]菌株在氧气（O）浓度为5%、10%、20%和40%的条件下培养时，大多数在20% O浓度下培养的菌株形成的棘状附属物最多。根据这些实验数据，[该属真菌]中的SSs/棘状附属物被认为具有呼吸功能。[该属真菌]可能获得了形成SS/棘状附属物的能力，以适应潮湿和/或水生栖息地，并分解氧气浓度通常较低的湿木。
