Salinity Tolerance in Kentucky Bluegrass Hybrids.

Salinity Tolerance in Kentucky bluegrass Hybrids Paul Harris, Paul Johnson, Shaun Bushman, Kelly Kopp Abstract Alternative sources of water, such as reclaimed water, generally have elevated salinity levels which put stress on turfgrass. Kentucky bluegrass (Poa pratensis) is sensitive to salinity stress, but is very well adapted to many turfgrass areas because of its dark color, durability, ability to recover from wear, and soft texture. Because of those positive traits, it has been the subject of selection for salinity tolerance. The objective of this experiment was to test differences in salinity tolerance among parental lines previously evaluated and hybrids among them. Forty four parent and hybrid plants established in 6.4 x 25.5 cm containers with silica sand were irrigated with increasing salinity levels. Plants were irrigated 1.25 cm every-other-day with an automated boom irrigation system. Treatments began at 3 dSm-1 for two weeks then increased to 6 dSm-1 for six weeks. Electrolyte leakage was measured to quantify salt stress along with visual ratings of plant health. The experiment was replicated 3 times. Grasses that consistently rated well were Hampton 768, North Star-3-5, 12-F9, and Bor-3-5. We found mixed results between electrolyte leakage and quality ratings, and individual entries didn’t always perform the same in replicate runs. We did find that the hybrid plants generally performed worse than the parents. We concluded that some Kentucky bluegrass hybrids have potential for use in environments with elevated salinity levels. Additional work will be needed to determine environmental adaptability, as well as evaluating turfgrass quality traits withstanding the stresses of routine turfgrass maintenance.