Growth and Quality Responses of Tall Fescue (Festuca arundinacea Schreb.) to Different Irrigation Levels and Nitrogen Rates

Abstract

A 2-year experiment was conducted to investigate the effects of different irrigation levels and nitrogen rates on visual turfgrass colour and quality and clipping yield of tall fescue (Festuca arundinacea Schreb.) under subhumid climatic conditions. The treatments consisted of five levels of irrigation, 25% (I1), 50% (I2), 75% (I3), 100% (I4) and 125% (I5), of the evaporation measured from a Class A pan and two rates of nitrogen, 25 kg N ha -1 (N1) and 50 kg N ha -1 (N2). The N rates were applied as a monthly rate during growing seasons (MaySeptember). The experimental area was irrigated by a pop-up sprinkler irrigation system. The irrigation was applied at 3-day intervals during May-September for both years. The seasonal crop evapotranspiration (ETc) under the treatments ranged from 315 to 1154 mm in 2007 and from 363 to 1100 mm in 2008. The ETc increased with increasing the both N rate and irrigation level, and the best seasonal turf quality of tall fescue was obtained for the I4 and I5 treatments under N2 rate. This study demonstrated that, when the level of irrigation and nitrogen rate were evaluated together, the N2I4 treatment ensured sufficiently dark turf colour and quality. Based on the results of this study, it is concluded that an acceptable turf quality can be sustained under the N1I1 treatment in May, N1I2 treatment in June, July and August and N1I4 treatment in September (or N2I2 treatment in September) according to water conservation. When rainfall amountis high (132.2 mm) in September, the N1I1 treatment may sustain acceptable turf quality for this month.

Assessing evidence on the agronomic and environmental impacts of turfgrass irrigation management

“…It is important to highlight the positive correlation between turfgrass quality and daily DMP in irrigated turfgrass. Where both variables were recorded in the same study, we observed a positive correlation, with R 2 values for the logistic regression ranging between .60 and .97 (Bañuelos et al., ; Candogan et al., , ; Lee, ; Qian & Engelke, ; Su et al., ; Telenko et al., ; Wherley, ). This nonlinear relationship shows that although low or zero growth rates might compromise turf quality, maximum turf quality scores are achieved before DMP rates reach their maximum.…”

“…Differences in turfgrass quality among species and varieties became more noticeable as the irrigation amount was reduced. In two studies conducted in Turkey, Candogan, Bilgili, Yazgan, and Acikgoz (, ) reported on the effects of irrigating perennial ryegrass ( Lolium perenne L.) and tall fescue ( Schedonorus arundinaceus [Schreb.] Dumort., nom.…”

“…Figure shows the reported variation in DMP for studies where the irrigation amount was varied. By irrigating at 50% Epan or less, DMP decreased markedly (e.g., Candogan et al., , ). However, the variation in DMP for different irrigation amounts also differed between studies.…”

“…Qian and Engelke () also reported negative impacts of over irrigation (115% vs. 55% Epan) in buffalograss due to too poor tolerance of the species to high irrigations, while tall fescue, bermudagrass and St. Augustine grass ( Stenotaphrum secundatum ) produced more dry matter in their clippings under regimes with high irrigation amounts. Despite the positive relation between DMP and irrigation, turfgrass DMP is more closely dependent on levels of N fertilisation (Candogan et al., , ). Figure shows the positive correlation between both variables based on reported observations from four studies.…”

“…These findings reportedly due to reductions in soil hydrophobicity and higher soil moisture uniformity. Candogan et al (2014Candogan et al ( , 2015 and Wang, Haver, and Pataki (2014) observed that turfgrass water consumption and the irrigation amounts required to produce acceptable turfgrass quality increased with increasing N fertilisation levels. Under non-limiting water conditions, turfgrass quality was more dependent on N than irrigation amount (Shaddox, Unruh, Trenholm, McGroary, & Cisar, 2016).…”