Abstract:
Summary
Community analyses of arbuscular mycorrhizal fungi (AMF) using ribosomal small subunit
(SSU) or internal transcribed spacer (ITS) DNA sequences often suffer from low resolution or
coverage. We developed a novel sequencing based approach for a highly resolving and specific profiling of AMF communities.
We took advantage of previously established AMF-specific PCR primers that amplify a
c. 1.5-kb long fragment covering parts of SSU, ITS and parts of the large ribosomal subunit
(LSU), and we sequenced the resulting amplicons with single molecule real-time (SMRT)
sequencing.
The method was applicable to soil and root samples, detected all major AMF families and
successfully discriminated closely related AMF species, which would not be discernible using
SSU sequences. In inoculation tests we could trace the introduced AMF inoculum at the
molecular level. One of the introduced strains almost replaced the local strain(s), revealing
that AMF inoculation can have a profound impact on the native community.
The methodology presented offers researchers a powerful new tool for AMF community
analysis because it unifies improved specificity and enhanced resolution, whereas the drawback of medium sequencing throughput appears of lesser importance for low-diversity groups
such as AMF.
