First report of community dynamics of arbuscular mycorrhizal fungi in radiocesium degradation lands after the Fukushima-Daiichi Nuclear disaster in Japan

Arbuscular mycorrhizal fungi (AMF) can be beneficial for improving restoration of radioactive-cesium ((137)Cs)-contaminated soils through soil remediation. However, there has been no information on species diversity and the composition of AMF communities in (137)Cs-contaminated soil after the Fukushima-Daiichi Nuclear Power Plant (NPP) disaster. We examined the community dynamics of indigenous AMF colonizing roots of napiergrass (Pennisetum purpureum) in two different (137)Cs-contaminated land-use fields (grassland and paddy field) by an Illumina MiSeq sequencing investigation within a 30-km radius around the Fukushima-Daiichi NPP in 2013 (sampling year 1) and 2014 (sampling year 2). We found nine AMF families, including Glomeraceae, Gigasporaceae, Paraglomeraceae, Claroideoglomeraceae, Acaulosporaceae, Archeosporaceae, Ambisporaceae, Diversisporaceae and uncultured Glomeromycotina in roots. Glomeraceae was the most abundant in both grassland and paddy field, followed by Paraglomeraceae. The diversity of AMF in grassland and paddy field was higher in 2014 than in 2013. Furthermore, the AMF community structure was impacted by sampling year and land-use type. The AMF community structures colonizing napiergrass roots were also significantly impacted by land-use type and year throughout the 2-year investigation. To our knowledge, our results are the first report to reveal the community dynamics of indigenous AMF in the (137)Cs-contaminated fields around NPP.