Seed Yield Potential of Tall Fescue Germplasm in the Great Plains of Wyoming.

Tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] is one of the most productive cool-season perennial grasses in the USA that can grow on a wide range of soils, has high drought and winter hardiness, and can be used for pasture, hay, stockpiling, silage, soil conservation, and turfgrass.  This grass can be a potential forage and seed crop in the Wyoming’s semi-arid environments.  The objective of this study is to identify tall fescue entries that will specifically be suitable for seed production in the Great Plains of Wyoming.  Three experimental entries and two standard cultivars of tall fescue were seeded in fall of 2008 under irrigated and dryland conditions at the Sustainable Agriculture Research and Extension Center near Lingle and the planting was repeated in spring of 2009.  The entries/cultivars were seeded (8 kg/ha) into small 1.5m×6m plots.  The experiments were laid out in randomized complete block design with four replications.  All the plots were irrigated for initial establishment of seedlings however, irrigation was stopped on dryland plots after establishment.  Seeds were harvested on July 31, 2009 using a combine.  Seed yield from the first year harvest showed a significant difference (P<0.0001) among the entries/cultivars.  A three-fold seed yield increase was recorded in irrigated plots compared to dryland plots (116 vs. 44 kg/ha) for cultivar ‘Fawn’.  Seed yield of all entries/cultivars in irrigated conditions varied from 116 kg/ha (‘Fawn’) to 367 kg/ha (PDF584).  Seed yield of PDF584 was not influenced by the irrigation and this entry produced higher seed yield (392 kg/ha) in dryland than irrigated plots.  The 1000-seed weight among the entries/cultivars ranged from 1.38 to 2.23 g in both irrigated and dryland plots.  Grasses are in great stand and data collection for 2010 is in the process.  Detailed data on seed yield and quality will be shown in the presentation.