Improving Drought Resistance and Persistence in Turf-Type Tall Fescue
2003
Carrow, R. N. | Duncan, R. R.
Improving tall fescue (Festuca arundinacea Schreb.) drought resistance is important for water conservation and persistence under drought stress. A 1996 to 1998 field study was conducted at Griffin, GA, to (i) assess effectiveness of a unique breeding/selection protocol designed to enhance drought/high temperature stress tolerances in tall fescue, and (ii) to determine the most drought resistant and persistent cultivars or ecotypes among 12 tall fescues. Six experimentals developed under various cycles of the GA breeding protocol (‘Southeast’ or 96-2, 96-3 to 96-7) were compared with five commercial cultivars and a Rutgers germplasm pool (RGP-1). The five grasses with the least average leaf firing (LF) during repeated dry-downs in 1997 and 1998 were from the GA gene pool, with average LF of four grasses exhibiting LF ≤ 14% compared with LF ≥ 29% for the commercial/RGP-1 pool. Persistence (percentage turf coverage) after 24 mo of repeated drought stress cycles revealed an average of 91 and 76% for the GA and commercial/RGP-1 pools, respectively, with Southeast and experimental 96-6 exhibiting the highest canopy coverage at 93%. Grasses demonstrating the best combined ranking of LF ≤ 14%; least change of turf quality (TQ) under repeated drought stress events with ΔTQ < 1.4; highest average TQ at TQ ≥ 6.4; and within the lowest evapotranspiration (ET) group (ET ≤ 2.72 mm d⁻¹) were all from the GA gene pool (Southeast, 96-5, 96-6, 96-7). This research provided strong documentation that significant enhancement of drought resistance and tall fescue persistence can be achieved by use of the GA breeding/selection protocol.
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