Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: July 21, 2011
Publication Date: October 16, 2011
Citation: Casler, M.D., Robins, J.G., Coblentz, W.K. 2011. Sparse-flowering orchardgrass is stable across temperate North America [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. Paper No. 235-7. Technical Abstract: Three sparse-flowering orchardgrass populations were developed by selective breeding as a mechanism to reduce stem production during the early spring season in management-intensive grazing systems. These populations and three check cultivars were evaluated under frequent- and infrequent-harvest systems at 21 locations in the USA and Canada in 2008-2010. Sparse-flowering populations had 61% fewer panicles than normal cultivars (48 vs. 125 panicles per square m). The sparse-flowering trait reduced first-cut forage yield by an average of 24%, but had little effect on regrowth yields. This effect was similar for both 3-cut and 5-cut harvest managements. The loss in forage yield of the sparse-flowering populations was partially compensated by an increase in quality, as measured by increased crude protein and digestibility, combined with reduced fiber. The sparse-flowering trait, including its impact on forage yield and quality, was stably expressed across temperate North America with relatively subtle variations associated with climate and geography.