Association between soil and root microbiomes and within-farm-spatial-variation of soybean yields I: The bacterial perspective.
Ananda Bandara - The Pennsylvania State University. Paul Esker- The Pennsylvania State University, Terrence Bell- The Pennsylvania State University, Dilooshi K. Weerasooriya- The Pennsylvania State University, Ryan Trexler- The Pennsylvania State University
The occurrence of high and low yielding sites within a farm has been a common yield limiting issue in soybean growing states. The causes behind such yield variations are currently unknown. We hypothesize that the potential differences of soil/root associated bacterial communities contribute to within-farm-spatial-variation of soybean yields (WFSVSY). Therefore, the objective of this study was to explore the bacterial communities of samples collected from high and low yielding sites at V1 and R8 soybean growth stages (SGS). Bulk soil (BS), rhizosphere soil (RS), and soybean root (R) samples were collected from eight farms in Pennsylvania (five high and low sites per farm). DNA extracted from samples were subjected to PCR targeting bacterial 16S rRNA genes (515F/806R primers) and amplicons were sequenced using MiSeq platform. The ?-diversity analysis did not distinctly cluster data points based on yield (high/low), farm, or SGS for BS and RS samples. For R samples, a clear clustering was observed based on SGS. In BS, ?-diversity was similar among high and low yield sites, however higher ?-diversity was observed in high yield sites for both RS and R. While RS showed higher ?-diversity at V1 compared to R8, the opposite was observed for R. There were no noticeable differences in relative abundances at the phyla level across high and low sites at V1 and R8. In-depth analysis will be performed to see whether specific bacterial taxa drive WFSVSY in Pennsylvania.