Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 5/3/2004
Publication Date: 10/31/2004
Citation: Casler, M.D., Barker, R.E., Cherney, J.H., Papadopolous, Y.A., Johnson, R.C., Jenderek, M.M. 2004. Breeding non-flowering orchardgrass [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. Paper No. 4380.
Technical Abstract: Orchardgrass (Dactylis glomerata L.) is a valuable pasture species in much of temperate humid North America. However, profuse and early flowering in spring creates management problems for graziers and reduces intake of livestock in a management-intensive rotational grazing system. Two sparse-flowering populations WO-SF-B and WO-SF-C have been shown to produce fewer panicles per plant have higher frequencies of sparse-flowering and non-flowering plants than orchardgrass cultivars. Plants have varying levels of expression of the non-flowering trait, ranging from slightly sensitive (sparse-flowering in one year) to highly sensitive (stable non-flowering across years), with highly sensitive plants found only within populations WO-SF-B and WO-SF C. The non-flowering trait of orchardgrass appears to be controlled by floral-regulation genes that are turned off by short-day temperatures below a critical threshold. Such a threshold appears to exist for all orchardgrass plants, but is increased in those plants expressing the non-flowering trait. Plants have been selected for further research to define the appropriate contrasting environments for optimal seed and forage production.