The Impact of Pine Wood Nematode Infection on the Host Fungal Community.

Yi Liu,Jie Xu,Hui Sun,Wen-Xiao Shen,Zhao-Lei Qu,Bing Liu,Yang Ma

doi:10.3390/microorganisms9050896

Yi Liu, Jie Xu + Show 5 more

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https://doi.org/10.3390/microorganisms9050896

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Abstract

Pine wilt disease (PWD), caused by pinewood nematode (PWN) Bursaphelenchus xylophilus, is globally one of the most destructive diseases of pine forests, especially in China. However, little is known about the effect of PWD on the host microbiome. In this study, the fungal community and functional structures in the needles, roots, and soil of and around Pinus thunbergii naturally infected by PWN were investigated by using high-throughput sequencing coupled with the functional prediction (FUNGuild). The results showed that fungal richness, diversity, and evenness in the needles of diseased trees were significantly lower than those of healthy ones (p < 0.05), whereas no differences were found in the roots and soil. Principal coordinate analysis (PCoA) showed that the fungal community and functional structures significantly differed only in the needles of diseased and healthy trees, but not in the soil and roots. Functionally, the saprotrophs had a higher abundance in the needles of diseased trees, whereas symbiotrophs abundance was higher in the needles of healthy trees (linear discriminant analysis (LDA) > 2.0, p < 0.05). These results indicated that PWN infection primarily affected the fungal community and functional structures in the needles of P. thunbergii, but not the roots and soil.

Highlights

Accepted: 19 April 2021Plant-associated microbes refer to total microorganisms that colonize the surface and interior of a plant, including fungi, bacteria, and archaea, and can be divided into phyllosphere, endosphere, and rhizosphere according to the different parts of plants [1,2]
Forests were originally dominated by conifer trees of P. thunbergii and P. massoniana Lamb, which are currently aged around 70 years
Good’s coverage of sequence was more than 98% for each sample, and sequencing depth effort is shown in Figure S1 as a rarefaction curve

Summary

Introduction

Plant-associated microbes refer to total microorganisms that colonize the surface and interior of a plant, including fungi, bacteria, and archaea, and can be divided into phyllosphere, endosphere, and rhizosphere according to the different parts of plants [1,2]. They can interact with the host plant in a beneficial, harmful, or neutral way [3,4,5]. Studies on forest tree microbiomes and their roles in mutualism and disease lag far behind parallel work on crop and human microbiome projects [6]. Many ectomycorrhizal or ericoid mycorrhizal fungi can form symbiotic relationships and interact with plants [8]

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