Kirker Grant T, Bishell Amy, Cappellazzi Jed, Palmer Jonathan, Bechle Nathan, Lebow Patricia, Lebow Stan
USDA-FS Forest Products Laboratory, Madison, WI 53726, USA.
Dept. of Wood Science and Engineering, Oregon State University, Corvallis, OR 97731, USA.
Microorganisms. 2020 May 9;8(5):696. doi: 10.3390/microorganisms8050696.
The effects of leaf litter on moisture content and fungal decay development in above-ground wood specimens were assessed. Untreated southern pine specimens were exposed with or without leaf litter contact. Two types of leaf litter were evaluated; aged (decomposed) and young (early stages of decomposition). The moisture content of specimens was monitored, and specimens were periodically removed for visual evaluation of decay development. In addition, amplicon-based sequencing analysis of specimens and associated leaf litter was conducted at two time points. Contact with either type of leaf litter resulted in consistently higher moisture contents than those not in contact with leaf litter. Visually, evident decay developed most rapidly in specimens in contact with the aged leaf litter. Analysis of amplicon-based sequencing revealed that leaf litter contributes a significant amount of the available wood decay fungal community with similar communities found in the litter exposed wood and litter itself, but dissimilar community profiles from unexposed wood. Dominant species and guild composition shifted over time, beginning initially with more leaf saprophytes (ascomycetes) and over time shifting to more wood rotting fungi (basidiomycetes). These results highlight the importance of the contributions of leaf litter to fungal colonization and subsequent decay hazard for above-ground wood.
评估了落叶对地上木材标本含水量和真菌腐朽发展的影响。未处理的南方松标本在有或没有落叶接触的情况下进行暴露。评估了两种类型的落叶：老化（已分解）的和年轻（分解初期）的。监测标本的含水量，并定期取出标本进行腐朽发展的目视评估。此外，在两个时间点对标本和相关落叶进行了基于扩增子的测序分析。与任何一种落叶接触的标本含水量始终高于未与落叶接触的标本。从视觉上看，与老化落叶接触的标本中明显的腐朽发展最快。基于扩增子的测序分析表明，落叶对可用的木材腐朽真菌群落有很大贡献，在接触落叶的木材和落叶本身中发现了相似的群落，但与未接触落叶的木材群落特征不同。优势物种和类群组成随时间变化，最初以更多的落叶腐生菌（子囊菌）为主，随着时间推移转向更多的木材腐朽真菌（担子菌）。这些结果突出了落叶对地上木材真菌定殖和后续腐朽危害的贡献的重要性。
