Cheatgrass (Bromus tectorum) has established itself as a prolific invader across the rangelands of the western United States, resulting in an abundance of fine fuel and an increased wildfire frequency. The increased frequency of fires has led to a significant reduction in native vegetation, causing degradation of wildlife habitat, forage availability, and other ecosystem services. To address this destructive wildfire cycle, cattle can be utilized to reduce cheatgrass fuel loads and mitigate cheatgrass dominance through targeted grazing. Concurrently, livestock may be used as vectors for the dispersal of desired rangeland plant species seeds through faecal seeding. Many seeds of interest are susceptible to microbial degradation in the rumen, which is why our study aimed to utilize in situ methods to evaluate the effects that seed coat enhancements have on the viability of seed germination post ruminal fermentation. Four target species, Indian ricegrass (Achnatherum hymenoides), crested wheatgrass (Agropyron c ristatum), bottlebrush squirreltail (Elymus elymoides), and bluebunch wheatgrass (Pseudoroegneria spicata), were coated with either Polyvinylpyrrolidone (PVP) or PVP + ethyl cellulose (Ethocel). The seeds were subjected to ruminal fermentation for 0, 6, 12, 24, 36, 48, 96 hours, after which, the seeds were placed into petri dishes and germination was monitored for five weeks. PVP and PVP + Ethocel coating treatments resulted in decreased germination rates for the 0-hour treatment across all species except Indian ricegrass. However, coated seeds exhibited greater resistance to microbial degradation through time. The exception to this was Indian ricegrass, which exhibited an increase in germination through time for PVP and control groups. Additionally, coated crested wheatgrass seeds were incubated in vitro for 48 hours and incorporated into faecal pats of varying depths to examine emergence. Emergence in faecal material was notable for the PVP + Ethocel group, indicating its potential to protect seeds under harsh environmental conditions.
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