Ryegrass Germplasm Overseeding Trials

Abstract

A field test was conducted to evaluate the turf performance of improved hybrid ryegrass (sometimes called intermediate ryegrass) Lolium hybridum versus that of perennial ryegrass germplasm (Lolium perenne) for winter overseeding purposes. "Gulf" annual ryegrass was also evaluated for comparison purposes. On all evaluation dates, the treatment effect was significant for all visual response variables measured (quality, color, texture, density, etc.). The mixture of LHRT hybrid ryegrass/Poa trivialis established quicker than other treatments during the first month (November). Perennial ryegrass entries provided the darkest color turf. Among hybrid ryegrasses, Pick A-97 was slightly darker in turf color when compared to LHRT. LHRT alone was darker in color than when mixed with Poa trivialis. In terms of overall turf quality, Pick A-97 and LHRT hybrid ryegrasses were essentially equal in performance. The spring decline was greater among hybrid ryegrasses than that of perennial ryegrass. Both hybrid ryegrasses (A-97 and LHRT) were superior to annual ryegrasses in all aspects of turf performance. By mid-June of 1999, Pick A-97 had more bermudagrass present (52%) than LHRT (28%). LHRT had more straw-colored (dead transition grass) than A-97 as well. By early July, A-97 and LHRT had 72% and 62% bermudagrass, respectively, and essentially the same amount of overseed present (20-23%). LHRT had 15% plot straw at this time, while A-97 had 8%. Among perennial ryegrasses, Sunshine had the slowest transition (42%), followed by Jiffie (50%) and Future 2500 (71%) by early July. The addition of Poa trivialis to LHRT hybrid ryegrass increased overall quality of the LHRT alone, but slowed transition slightly, most likely due to increased canopy densities achieved by the addition of Poa trivialis. This test demonstrated that the hybrid ryegrass germplasm tested here provided adequate fairway turf performance, and that transition among and between Lolium germplasm is variable, and genetically dependant.