Understanding rhizome and tiller traits as an approach to improve fine fescue sod

Abstract

Rhizomes and tillers are important morphological features for many turfgrasses and are traits deserving of more focus for cool-season turfgrass breeding. These two types of stems can allow for resilience and competitiveness in a lawn. Rhizomes and tillers are helpful for sod production which requires turf to be able to quickly form a thick mat of interlocking plant material that can hold together during harvest and transplanting. Kentucky bluegrass (Poa pratensis L.) has the ability to form rhizomes, and is the predominant sod species in Minnesota and the surrounding states. However, consumers would benefit from increased availability of species which require fewer inputs such as fine fescue (Festuca L. spp.) sod for lawns and roadsides. Strong creeping red fescue (Festuca rubra L. subsp. rubra Gaudin) displays robust rhizomatous growth that parallels Kentucky bluegrass and shows promise as a low-input sod option. However, strong creeping red fescue breeding has not been improved for rhizome production or improved sod characteristics. For my dissertation, I pursued breeding and genomics approaches to assess fine fescues of the Festuca rubra complex for sod improvement with a focus on strong creeping red fescue stem growth and development as components of sod formation. I characterized diversity of available germplasm via molecular genetic markers, phenotypes in the growth chamber and field environments, and evaluated the effect of photoperiod on rhizome and tiller production. This investigation of rhizome and tiller traits of these fine fescue taxa could help plant breeders develop new low-input cultivars with enhanced sod forming ability.