As water resources in many areas, but particularly the western United States, become more limiting and are sought by competing interests, there is a need for turfgrass species that require less irrigation for low-maintenance situations (Feldhake et al., 1983). The need to identify new lower water-requiring turfgrass species has resulted in the characterization of many perennial grass species for turfgrass potential (Diesburg et al., 1997), including crested wheatgrass [Agropyron cristatum (L.) Gaertn.]. Crested wheatgrass is a perennial Triticeae grass species, is well suited to harsh semiarid conditions, and is a key species for revegetation and forage production on rangelands of the Great Plains and intermountain regions of the United States (Asay and Jensen, 1996). Several studies have investigated the potential (Bushman et al., 2007; Diesburg et al., 1997; Hanks et al., 2006; Robins et al., 2006) and breeding (Asay et al., 1999; Hanks et al., 2005) of crested wheatgrass for turf. ‘RoadCrest’ was the first crested wheatgrass cultivar specifically developed for turf use (Asay et al., 1999), although other cultivars such as ‘Ephraim’ (Stevens et al., 1983) and ‘Fairway’ (Kirk, 1932) are commonly used in roadside stabilization and other low-maintenance turf situations. Breeding efforts are ongoing for further crested wheatgrass turf improvements.
A potential roadblock to higher public acceptance of crested wheatgrass turf is its poorer performance for turf characteristics such as color, quality, and increased tendency for summer dormancy when compared with traditional turf species (Bushman et al., 2007; Robins et al., 2006). Turf quality is a particularly important trait and consists of the combination of color intensity, leaf texture, and tiller density (Gibeault et al., 1989; Skogley and Sawyer, 1992) and can be affected by pest resistance. Hanks et al. (2005) identified the rapid spring growth and reduced summer turf quality as the most limiting characteristics of crested wheatgrass for turfgrass. However, the study also identified high levels of broad-sense heritability for turf quality and suggested that breeding efforts aimed at increasing crested wheatgrass turf quality would be successful (Hanks et al., 2005). Although high broad-sense heritabilities suggest the importance of genetic as compared with environmental factors (Holland et al., 2003; Nyquist, 1991), they are not indicative of the potential that can be made in a breeding program.
The objective of this study was the estimation of genetic variation and narrow-sense heritability for turf quality in a population of half-sib families. These families represent breeding materials used in ongoing efforts at improving turf-quality traits in crested wheatgrass for low-maintenance turfgrass conditions.
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