Inoculation with natural microbial suspension and phytate amendment as
sole source of phosphorus increased soybean growth and shifted microbial
Phytate represents an organic pool of phosphorus in soil that require
hydrolysis by phytase enzymes produced by microorganisms prior to its
bioavailability by plants. We hypothesize that in a greenhouse trail on
soybean plants inoculated or non-inoculated with a microbial suspension
made from an age-old maple forest’s undisturbed soil mineralize phytate.
MiSeq Amplicon sequencing targeting bacterial 16S rRNA gene and fungal
ITS was performed to assess microbial community changes following
treatments. Our results showed that soybean nodulation and shoot dry
weight biomass increased when phytate was applied to the nutrient-poor
substrate mixture. Bacterial and fungal diversities of the root and
rhizosphere biotopes were relatively resilient following inoculation by
microbial suspension; however, bacterial community structure was
significantly influenced. Interestingly, four arbuscular mycorrhizal
fungi (AMF) were identified as indicator species, including Glomus sp.,
Claroideoglomus etunicatum, Funneliformis mosseae and an unidentified
AMF taxon. We also observed that an ericoid mycorrhizal taxon Sebacina
sp. and three Trichoderma spp. were among indicator species.
Non-pathogenic Planctobacteria members highly dominated the bacterial
community as core and hub taxa for over 80% of all bacterial datasets
in root and rhizosphere biotopes. Overall, our study documented that
inoculation with a microbial suspension and phytate amendment improved
soybean plant growth.