Utilization of 'TifGrand' bermudagrass for sports turf: wear tolerance, shade response, and quality improvement.

Abstract

‘TifGrand’ is a relatively new, reportedly wear-, shade-, and drought-tolerant bermudagrass cultivar. TifGrand is similar to other bermudagrasses such as ‘Tifway’ and ‘TifSport’, and yet, displays some unique features, uncommon to its family. Studies were conducted to evaluate and compare TifGrand to other bermudagrass cultivars for wear tolerance, as influenced by increasing levels of simulated wear applied with a Cady Traffic Simulator, similarly to American-football wear. Wear tolerance was investigated as in fall durability during simulation of wear, and spring response following fall wear-simulation. TifGrand consistently resulted in equal or greater fall durability, green cover, traction, and spring recovery, compared to other cultivars. Whereas some differences were noticed under light traffic, pronounced cultivar differences were noticed under higher frequencies of uninterrupted simulated wear. Studies were also conducted to evaluate and compare TifGrand to other bermudagrass cultivars as influenced by different shade regimes. Diurnal shade regimes, as well as continuous, increasing shade levels were simulated and turfgrass responses analyzed. TifGrand resulted in superior performance under moderate shade when compared to full-sun. Etiolation was a key factor in bermudagrass shade tolerance: cultivars with decreased etiolation (TifGrand and ‘TifSport’) resulted in superior quality. Physiological adaptations were also noticed, however, as a response to shading rather than as a tolerance mechanism. Additionally, herbicides and PGRs were applied attempting to suppress TifGrand seedhead formation, and to increase aesthetic quality. Flucarbazone plus trinexapac-ethyl and imazethapyr successfully suppressed TifGrand seedheads safely, resulting in quality improvement.