Department of Biology, Lund University, Lund, Sweden.
Department of Plant Protection Biology, Swedish University of Agricultural Sciences, SLU, Alnarp, Sweden.
ISME J. 2021 Jun;15(6):1782-1793. doi: 10.1038/s41396-020-00886-7. Epub 2021 Jan 19.
How do fungi navigate through the complex microscopic maze-like structures found in the soil? Fungal behaviour, especially at the hyphal scale, is largely unknown and challenging to study in natural habitats such as the opaque soil matrix. We monitored hyphal growth behaviour and strategies of seven Basidiomycete litter decomposing species in a micro-fabricated "Soil Chip" system that simulates principal aspects of the soil pore space and its micro-spatial heterogeneity. The hyphae were faced with micrometre constrictions, sharp turns and protruding obstacles, and the species examined were found to have profoundly different responses in terms of foraging range and persistence, spatial exploration and ability to pass obstacles. Hyphal behaviour was not predictable solely based on ecological assumptions, and our results obtained a level of trait information at the hyphal scale that cannot be fully explained using classical concepts of space exploration and exploitation such as the phalanx/guerrilla strategies. Instead, we propose a multivariate trait analysis, acknowledging the complex trade-offs and microscale strategies that fungal mycelia exhibit. Our results provide novel insights about hyphal behaviour, as well as an additional understanding of fungal habitat colonisation, their foraging strategies and niche partitioning in the soil environment.
真菌如何在土壤中复杂的微观迷宫状结构中导航？真菌的行为，特别是菌丝尺度上的行为，在自然栖息地（如不透明的土壤基质）中很大程度上是未知的，并且难以研究。我们在模拟土壤孔隙空间及其微空间异质性主要方面的微制造“土壤芯片”系统中监测了七种担子菌落叶分解物种的菌丝生长行为和策略。菌丝面临着微米级的收缩、急转弯和突出的障碍物，被检查的物种在觅食范围和持久性、空间探索和通过障碍物的能力方面表现出明显不同的反应。菌丝行为不能仅根据生态假设来预测，我们的结果在菌丝尺度上获得了一种特征信息水平，这不能完全用经典的空间探索和利用概念（如方阵/游击策略）来解释。相反，我们提出了一种多变量特征分析，承认真菌菌丝表现出的复杂权衡和微观策略。我们的结果提供了关于菌丝行为的新见解，以及对真菌栖息地定殖、觅食策略和土壤环境中生态位划分的进一步理解。
