Limited information is available on the optimal frequency and amounts of irrigation water needed to establish cool-season turfgrasses from seed in arid environments. A 2 × 2 factorial study was conducted at New Mexico State University in 2012 and repeated in 2017 to investigate the effect of four irrigation treatments: two reference evapotranspiration (ET_o) rates (60 and 120%), and two frequencies (daily and every other day [EOD]) on the establishment of several varieties of Kentucky bluegrass (Poa pratensis L.), perennial ryegrass (Lolium perenne L.), and tall fescue [Schedonorus arundinaceus (Schreb.) Dumort] (TF). Our hypothesis was that irrigation rates below 100% ET_o replacement applied EOD would negatively affect turfgrass establishment. Turfgrasses were seeded in the fall and digital image analysis was used to estimate percent coverage. The Area Under the Curve model was used to estimate days after seeding needed to reach 50 (DAS50) and 90% coverage (DAS90). Statistical analysis indicated a significant interaction (p < .0001) between ET_o and species and that irrigation frequency did affect establishment. Perennial ryegrass established the fastest and DAS90 was not affected by irrigation treatment. Kentucky bluegrass and TF established faster when irrigated daily at 120% ET_o. Varieties within the same species all performed equally. In general, our study suggests that cool-season turfgrasses can be established in arid regions using water conserving measures such as irrigating EOD at rates below 100% ET_o replacement. Further studies are needed to determine lowest ET_o replacement levels or irrigation frequency possible to achieve establishment.

中文翻译：

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优化建立冷季草坪所需的灌溉频率和数量

关于在干旱环境中从种子中建立冷季型草坪草所需的最佳灌溉水频率和数量的信息有限。2012 年在新墨西哥州立大学进行了一项 2 × 2 因子研究，并于 2017 年重复研究四种灌溉处理的效果：两种参考蒸散 (ET _o ) 率（60% 和 120%）和两种频率（每天和每前几天 [EOD]) 建立了几个品种的肯塔基早熟禾 ( Poa pratensis L.)、多年生黑麦草 ( Lolium perenne L.) 和高羊茅 [ Schedonorus arundinaceus (Schreb.) Dumort] (TF)。我们的假设是灌溉率低于 100% ET _o更换应用 EOD 会对草坪草的建立产生负面影响。草坪草在秋季播种，数字图像分析用于估计覆盖率。曲线下面积模型用于估计播种后达到 50 (DAS50) 和 90% 覆盖率 (DAS90) 所需的天数。统计分析表明 ET _o和物种之间存在显着的相互作用 ( p < .0001)，灌溉频率确实影响建立。多年生黑麦草生长最快，DAS90 不受灌溉处理的影响。每天以 120% ET _{o灌溉时，肯塔基早熟禾和 TF 建立得更快}. 同一物种内的品种都表现相同。总的来说，我们的研究表明，可以使用节水措施在干旱地区建立冷季型草坪草，例如以低于 100% ET _o替换率灌溉 EOD。需要进一步的研究来确定最低 ET _o替代水平或灌溉频率可能实现建立。