Date of Graduation

5-2013

Document Type

Dissertation

Degree Name

Doctor of Philosophy in Plant Science (PhD)

Degree Level

Graduate

Department

Horticulture

Advisor

Michael D. Richardson

Committee Member

Douglas E. Karcher

Second Committee Member

Aaron J. Patton

Third Committee Member

Derrick M. Oosterhuis

Fourth Committee Member

Kristofor R. Brye

Fifth Committee Member

Rick Bennett

Abstract

Golf course superintendents are managing creeping bentgrass (Agrostis stolonifera L.) putting greens throughout the transition zone where temperatures can exceed optimum levels for consecutive days in the summer. The stress of creeping bentgrass associated with these supraoptimal temperatures has been well documented, but the management practices implemented on putting greens to increase green speeds may exacerbate these environmental stresses. To date, the physiological effects of these management practices in combination have not been evaluated for putting green turf. The objective of this dissertation project was to determine the effect of mowing heights, light-weight rolling, and foot traffic on performance and physiological parameters of `SR 1020' and `Penn G2' creeping bentgrass. Both above and below ground performance characteristics were evaluated in this project including: wear tolerance, turf quality, turf coverage, turf color, rooting characteristics, ball roll distance, ball mark severity, and ball mark recovery. Physiological data were collected with a custom photosynthesis chamber, and carbohydrate analysis was performed for all mowing and rolling treatments. Individual carbohydrates (total ethanol soluble sugars, glucose, sucrose, fructans, and average degree of polymerization) were determined for foliage, crown, and root material of each sample. Both performance characteristics and physiological parameters reached poorest levels in July or August each year as environmental stresses increased. Plots maintained at higher mowing heights and reduced rolling frequencies maintained better wear tolerance, turf quality, coverage, and color compared to lower mowing heights with frequent rolling. Net photosynthesis increased slightly as mowing heights were increased, but few significant differences were observed for these treatment combinations. Few consistent differences were observed for carbohydrate analysis with lower mowing heights or increased rolling frequencies, but increased mowing height generally resulted in higher carbohydrate concentrations in foliage and crown material following heat stress. Ball mark severity was rarely affected by these treatment combinations, but increased rolling frequencies increased maximum ball mark injury and extended recovery time. Fewer significant differences were observed for these parameters compared to initial expectations, but increased mowing heights and reduced rolling frequencies generally created healthier turf.

Share

COinS