Monday, November 5, 2007
74-8
Chemical and Cultural Management Practices to Enhance ‘Champion' Bermudagrass Under Shade.
Christian Baldwin, Haibo Liu, Lambert McCarty, Nihal Rajapakse, Hong Luo, and Joe Toler. Hoeticulture, Clemson University, 143 P & A Building, Clemson, SC 29634
Managing warm-season turfgrasses when sunlight is blocked is challenging due to morphological limitations, such as reduced lateral stem growth. Proper cultural practices such as nitrogen and trinexapac-ethyl (TE) [4-(cyclopropyl-a-hydroxy-methylene)-3,5-dioxocyclohexanecarboxylic acid ethyl ester] are critical for successful turfgrass culture when sunlight is minimal. Therefore, a two-year field study from 15 June to 15 September 2006 and 2007 at Clemson University determined the best combination of management practices for sustaining a high quality ‘Champion’ bermudagrass (Cynodon dactylon (L.) Pers. X C. transvaalensis) putting green in shade. Treatments included continuous full-day 55% shade, TE applications (0.05 kg a.i. ha-1) every two weeks, iron applications (2.7 kg a.i. ha-1) every two weeks, and nitrogen (N) applications as urea (46-0-0) at rates of 147, 293, and 437 kg ha-1 every two weeks. Data collection included visual turfgrass quality (TQ) rated weekly from 1-9 (1=brown, dead turf, 7=acceptable quality, and 9=perfect, green turfgrass) based on color, density, texture, and uniformity of the bermudagrass surface. Total clipping yield and shoot chlorophyll concentration were collected at the middle and end of the study. Total non-structural carbohydrates were analyzed at the conclusion of the study. When grown in full-sun, results suggest best treatment combination is 437 kg N ha-1, along with TE and iron. Under 55% shade, best management practices are to fertilize with 147 or 293 kg N ha-1, as well as TE applications every two weeks with or without iron. Poorest quality turfgrass in shade was 437 kg N ha-1 without TE or iron.