Seedmeal_16S
Soil bacterial community responses to oilseed meal addition
The goals of this study were to characterize the bacterial and fungal community responses to the addition of various biomass amendments, including Brassica juncea oilseed meal (brown mustard, a glucosinolate-containing seed meal), Linum usitatissimim (flax, a non-glucosinolate-containing oilseed meal), Sorghum bicolor (sorghum-sudangrass, a non-oilseed biomass source) at multiple time points across a 4-week laboratory-scale incubation. A non-amended control was studied characterized as well.  Incubations were performed in triplicate, and samples were collected after 3, 7, 14, and 28 days' incubation. Community DNA was extracted from each sample and submitted to the Research and Testing Laboratory (Lubbock, TX) for tag-pyrosequencing of the bacterial 16S rRNA gene. This data set contains 16S rRNA gene sequences for each of the 48 samples collected during this study (4 amendment types, 4 time points, and 3 replicates of each). A companion data set, containing fungal ITS gene sequence data will also be submitted.
Demand for bio-based fuels has sparked renewed interest in the use of oil-rich seeds for biodiesel production. Oilseed meals are a byproduct of this process. Although some can be used as animal feed, others are too toxic. Given that oilseed meals are relatively nutrient rich, land application as organic fertilizer or biofumigants represents a potential alternative use. In this study, soil bacterial and fungal community responses to amendments of a glucosinolate-containing brassicaceous oilseed meal (Brassica juncea), a non-glucosinolate-containing, non-brassicaceous oilseed meal (Linum usitatissimum), and a non-oilseed biomass (Sorghum bicolor) were characterized using replicated 16S rRNA gene sequence libraries at 4 time points over the course of a 28-day laboratory incubation. We hypothesized that both oil residue and glucosinolate content would alter community composition but that effects would diminish over time. Distinct separation of the bacterial andcommunities occurred along amendment-type lines, with mustard inducing large, short-lived increases in the abundance of Bacilli. Other amendments contributed to increased abundances of Actinobacteria. Shifts in bacterial community composition tended to be short-lived (i.e. days) but suggest that oilseed amendment has the potential to alter soil microbial community structure, particularly in the case of mustard.