Vegetative Growth of Greens-Type Poa annua Relative to Other Cool-Season Turfgrass Species

Salt problems on golf courses are increasing in both frequency and severity primarily due to the decreasing availability of fresh water resources. Driven by local water conservation plans, more and more golf courses are irrigated with effl uent water, which is usually high in salinity and rich in detrimental salts (Marcum et al., 1998; Suplick-Ploense et al., 2002). Salt can have adverse eff ects on turfgrass growth including physiological drought, ion toxicity, and ion imbalances (Carrow and Duncan, 1998; Carrow et al., 2001). Most cool-season turfgrass species are particularly suscep-tible to salinity stress during seed germination with the possible exception of perennial ryegrass (Lolium perenne L.) (Dudeck and Peacock, 1985; Harivandi et al., 1992). Therefore, soils and irriga-tion water with high salinity levels are often more of an obstacle to turf establishment than to the maintenance of mature turfgrass (Qian and Suplick, 2001). As salt problems become one of the most complex management challenges, screening and breeding cool-season turfgrass cultivars that are salt-tolerant during both seed germination and vegetative growth becomes important. Poa annua L. (annual bluegrass), a member of the Poacea