Wicaksono Wisnu Adi, Semler Bettina, Pöltl Martina, Berg Christian, Berg Gabriele, Cernava Tomislav
Institute of Environmental Biotechnology, Graz University of Technology, Graz, 8010, Austria.
Institute of Biology, University of Graz, Graz, 8010, Austria.
Environ Microbiome. 2023 Jun 1;18(1):46. doi: 10.1186/s40793-023-00501-0.
The microbiota of liverworts provides an interesting model for plant symbioses; however, their microbiome assembly is not yet understood. Here, we assessed specific factors that shape microbial communities associated with Riccia temporary agricultural crusts in harvested fields by investigating bacterial, fungal and archaeal communities in thalli and adhering soil from different field sites in Styria and Burgenland, Austria combining qPCR analyses, amplicon sequencing and advanced microscopy.
Riccia spec. div. was colonized by a very high abundance of bacteria (10 16S rRNA gene copies per g of thallus) as well as archaea and fungi (10 ITS copies per g of thallus). Each Riccia thallus contain approx. 1000 prokaryotic and fungal ASVs. The field type was the main driver for the enrichment of fungal taxa, likely due to an imprint on soil microbiomes by the cultivated crop plants. This was shown by a higher fungal richness and different fungal community compositions comparing liverwort samples collected from pumpkin fields, with those from corn fields. In contrast, bacterial communities linked to liverworts are highly specialized and the soil attached to them is not a significant source of these bacteria. Specifically, enriched Cyanobacteria, Bacteroidetes and Methylobacteria suggest a symbiotic interaction. Intriguingly, compared to the surrounding soil, the thallus samples were shown to enrich several well-known bacterial and fungal phytopathogens indicating an undescribed role of liverworts as potential reservoirs of crop pathogens.
Our results provide evidence that a stable bacterial community but varying fungal communities are colonizing liverwort thalli. Post-harvest, temporary agricultural biocrusts are important reservoirs for microbial biodiversity but they have to be considered as potential reservoirs for pathogens as well.
地钱的微生物群为植物共生提供了一个有趣的模型；然而，它们的微生物群落组装尚未得到理解。在这里，我们通过对奥地利施蒂里亚州和布尔根兰州不同田间地点的叶状体和附着土壤中的细菌、真菌和古菌群落进行qPCR分析、扩增子测序和先进显微镜检查，评估了影响与采收田地中扁萼苔临时农业结皮相关的微生物群落的特定因素。
扁萼苔属多样性被非常高丰度的细菌（每克叶状体10个16S rRNA基因拷贝）以及古菌和真菌（每克叶状体10个ITS拷贝）定殖。每个扁萼苔叶状体包含约1000个原核生物和真菌扩增子序列变体。田间类型是真菌类群富集的主要驱动因素，这可能是由于栽培作物对土壤微生物群的印记。这通过比较从南瓜田和玉米田采集的地钱样本，显示出更高的真菌丰富度和不同的真菌群落组成得到证明。相比之下，与地钱相关的细菌群落高度专业化，附着在它们上面的土壤不是这些细菌的重要来源。具体而言，富集的蓝细菌、拟杆菌和甲基杆菌表明存在共生相互作用。有趣的是，与周围土壤相比，叶状体样本显示富集了几种著名的细菌和真菌植物病原体，这表明地钱作为作物病原体的潜在储存库具有未被描述的作用。
我们的结果提供了证据，表明稳定的细菌群落但不同的真菌群落定殖在地钱叶状体上。收获后，临时农业生物结皮是微生物多样性的重要储存库，但它们也必须被视为病原体的潜在储存库。
