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A novel metagenomics method was produced for taxonomic analysis of a community of soil bacteria via quantitative polymerase chain reaction (qPCR). Taxonomies were confirmed via phylum-specific primers targeting various regions of the 16S DNA gene. Through this method, the effects of common herbicides on soil bacterial communities were determined. This method was verified by direct comparison to shotgun sequencing of the same DNA library used for qPCR. Taxonomic analysis of a similar accuracy as metagenomic shotgun sequencing was achieved. The novel method improves the ability to taxonomically analyze soil bacterial communities without specialized equipment for DNA sequencing.

Rhizomes facilitate the wintering and vegetative propagation of many perennial grasses. Sorghum halepense (johnsongrass) is an aggressive perennial grass that relies on a robust rhizome system to persist through winters and reproduce asexually from its rootstock nodes. This study aimed to sequence and assemble expressed transcripts within the johnsongrass rhizome. A de novo transcriptome assembly was generated from a single johnsongrass rhizome meristem tissue sample. A total of 141,176 probable protein-coding sequences from the assembly were identified and assigned gene ontology terms using Blast2GO. The johnsongrass assembly was compared to Sorghum bicolor, a related non-rhizomatous species, along with an assembly of similar rhizome tissue from the perennial grain crop Thinopyrum intermedium. The presence/absence analysis yielded a set of 259 johnsongrass contigs that are likely associated with rhizome development.

Isolated in scattered remnants, less than 0.1% of Iowa's original tallgrass prairie remains. The small populations remaining are at risk for reduced genetic diversity, inbreeding depression, and outbreeding depression. In light of these concerns, we used microsatellite analysis to assess the genetic structure of butterfly milkweed (Asclepias tuberosa) populations on prairie remnants in northwest Iowa. We compared remnant populations with a restoration population at Dordt College in Sioux Center, Iowa, and with an Oklahoma seed source. Microsatellites identified for use in common milkweed (Asclepias syriaca) had sufficient polymorphism information content (PIC) across the butterfly milkweed (A. tuberosa) populations sampled (mean PIC = 0.624). The FIS values indicated a lack of inbreeding (mean FIS = −0.1455) even in the commercially expanded seed. The pairwise FST values showed a low degree of differentiation among the remnants (mean FST = 0.0453) but a moderate degree (mean FST = 0.105) of differentiation when comparing the remnants to the Dordt restoration or to seed from Oklahoma. Despite massive loss and fragmentation of the tallgrass prairie, our microsatellite analysis revealed no evidence of inbreeding in A. tuberosa. However, evidence of genetic differentiation suggests that effort should be made to preserve the diversity still present. Seed expansion efforts appear to have had minimal impact on overall genetic diversity, although the diversity in particular selectable traits may be reduced. The differences between the genetics of the propagated seed at the Dordt restoration and the Oklahoma seed when compared to native remnants support the usefulness of source-identified seed.

Rhizomes facilitate the wintering and vegetative propagation of many perennial grasses. Sorghum halepense (johnsongrass) is an aggressive perennial grass that relies on a robust rhizome system to persist through winters and reproduce asexually from its rootstock nodes. This study aimed to sequence and assemble expressed transcripts within the johnsongrass rhizome. A de novo transcriptome assembly was generated from a single johnsongrass rhizome meristem tissue sample. A total of 141,176 probable protein‐coding sequences from the assembly were identified and assigned gene ontology terms using Blast2GO. Estimated expression analysis and BLAST results were used to reduce the assembly to 64,447 high‐confidence sequences. The johnsongrass assembly was compared to Sorghum bicolor, a related nonrhizomatous species, along with an assembly of similar rhizome tissue from the perennial grain crop Thinopyrum intermedium. The presence/absence analysis yielded a set of 98 expressed johnsongrass contigs that are likely associated with rhizome development.