Pine wilt disease alters soil properties and root-associated fungal communities in Pinus tabulaeformis forest

Aims The objective was to elucidate how pine wilt disease impacts soil properties and root-associated fungi in Pinus tabulaeformis forest. Methods Soil responses to pine wilt disease were studied in three kinds of damaged (undisturbed, middle disturbed and high disturbed) stands. The responses of root-associated fungal community structure and diversity were examined through Illumina MiSeq sequencing of tagged amplicons of the 18S rDNA region. Soil nutrient properties were compared among stands using standard techniques. Results Stands disturbed by pine wilt disease had lower soil hyphal density, pH, P and K content, higher organic matter and higher total N (P < 0.05) compared with undisturbed stands. With the increasing of disease damage, the root ergosterol content, the colonization rates of ectomycorrhizal fungi and total hyphae were significantly decreased (P < 0.05). Dark septate endopasitic fungi decreased firstly and then increased again with the increased severity of disease. The composition of root-associated fungi differed among three kinds of disturbed stands. Basidiomycota and Ascomycota were the dominant root-associated fungi of P. tabulaeformis. Tuber, as the most abundant fungal taxa, predominated in the undisturbed stand, while Russula in high disturbed stand. The community richness and diversity of root-associated fungi were significantly lower (P < 0.01) in high disturbed stand than that of undisturbed stand. Conclusions Pine wilt disease alters soil biotic and nutrient properties. Our study revealed clear differences in the biomass, abundance, diversity and community structure of root-associated fungi among three pure P. tabulaeformis stands. Analysis of dominated RAF abundance provides one of methods to predict the damage degree of pine wilt disease to some extent.