Optimizing Pre-Germination Techniques for Three Turfgrass Species: Bentgrass, Kentucky Bluegrass and Perennial Ryegrass.

Many intensively trafficked areas such as athletic fields and golf courses require constant overseeding. Rapid seed germination and subsequent development are critical to managing these high wear areas. The objectives of this research were to determine the effect of water aeration, soaking duration, and water temperature on the mean germination time (MGT) and percent germination of three turfgrass species; Kentucky bluegrass (Poa pratensis, KBG), perennial ryegrass (Lolium perenne, PRG) and creeping bentgrass (Agrostis stonlonifera, CBG).

Two separate studies were conducted. The first was designed as a 2x3x4 factorial with an untreated control. Treatments were arranged in a split plot design with aeration/no aeration as the main plot split by species and soaking duration (8, 24, 48, and 72 hours) with an untreated control. Treatments were replicated three times within three runs completed at 20°C in a growth chamber. The second experiment was a 3x3x3 factorial nested, split plot with an untreated control. This experiment examined the effect of soaking duration (8, 24, and 48 hours) and water temperature (4, 20, 30°C) on seed germination for the three species. A total of three runs were completed, each consisting of three treatment replications.

Water aeration had little effect on treatments across turfgrass species, except PRG.  Therefore, aeration is not recommended for pre-germinating KBG and CBG.  Soaking duration and temperature had significant effects for KBG and CBG only.  KBG MGT was optimal at 20°C water temperature for 24h.  CBG MGT was optimal at 20°C for 48h.  To optimize MGT of PGR, seed should be aerated and soaked for 8h.  These results indicate that soaking duration and water temperature were not critical factors for PGR as there was no benefit to longer soaking durations or varying water temperatures.