Establishment and performance of bluegrass species and tall fescue under reduced-input maintenance in a temperate Mediterranean environment

Abstract

Turfgrass water conservation has become important in many parts of the world, including the transition zones of Mediterranean Europe. Species selection is considered one of the most important factors influencing turfgrass water use, and drought-tolerant cool-season species are encouraged to be used in areas where long dormancy periods of warm-season grasses is unacceptable. A field study was conducted from Mar. 2007 to Sept. 2009 at Padova University, Italy, to evaluate establishment and performance of nine turfgrass cultivars under reduced-input maintenance. The study included hybrid bluegrass (Poa pratensis × P. arachnifera) cultivars Solar Green, Thermal Blue, and Thermal Blue Blaze; kentucky bluegrass (Poa pratensis) cultivars Cocktail, Cynthia, and Geronimo; and tall fescue (Festuca arundinacea) cultivars Apache, Murray, and Regiment. Establishment rate was assessed after two seeding dates (20 Mar. and 20 Sept.), and grasses were subsequently fertilized with 15 g·m-2 nitrogen per year and irrigated once every 2 weeks at 40% of reference evapotranspiration from June to August. Turfgrass and weed cover were estimated 60 days after seeding (DAS), and turf quality was evaluated weekly on a scale of 1 (worst) to 9 (best). Normalized difference vegetation index (NDVI) was measured weekly during 2009. Tall fescue cultivars exhibited greater quality than hybrid bluegrass or kentucky bluegrass, under both spring and autumn seeding. Hybrid bluegrass had similar quality to kentucky bluegrass cultivars, although they performed well only when sown in autumn. Our results suggest that among the tested grasses, tall fescue performed better under the reduced irrigation in a Mediterranean transition zone climate than kentucky bluegrass or hybrid bluegrass.