TRINEXAPAC-ETHYL AND OVERSEEDING EFFECTS ON SHEAR STRENGTH OF FOUR BERMUDAGRASS CULTIVARS GROWN ON SAND-BASED SYSTEM

摘要

Bermudagrasses (Cynodon dactylon (L.) Pers.; C.dactylon x C.transvaalensis Burt-Davey) is often used for athletic fields due in part to the excellent playing surfaces they provide.Minimal research evaluating shear strength of bermudagrass cultivars used for athletic turf have been completed and published.The objective of this study was to evaluate the effects of cultivars,applications of TE,and overseeding with perennial ryegrass on shear strength of bermudagrasses grown on a sand-based system.The cultivars ‘Quickstand’,‘Tifway 419’,‘Riviera’,and ‘Yukon’ grown in a sand-based medium were used to investigate differences in shear strength.Trinexapac-ethyl (TE) was applied at label rates and frequencies or untreated.Perennial ryegrass (Lolium perenne L.) was overseeded at 0,612,and 1224 kg.pure live seed (PLS) per hectare.Shear tests were conducted once wk-1August through November in 2007 and 2008 using the Clegg shear tester.Significant differences (p<0.05) in shear strength indicated Quickstand= Riviera > Tifway 419 =Yukon (2007) and with Riviera ≥ Quickstand > Tifway 419 = Yukon (2008).Significant differences (p<0.05) in shear strength due to overseeding were not observed in 2007 and only for the last three observation dates in 2008 where a significant (p<0.05) decrease in shear strength was observed.Applications of TE had no significant (p>0.05) effects on shear strength in either year of the study.Cultivar was the most important parameter for shear strength with Riviera consistently providing greater shear strength.