For selecting native turfgrass species which had stronger drought resistances, pot cultivation experiment was conducted to study the effects on the survival days,dynamic of daily mean evapotranspira-tion rate, wilting coefficients,soil moisture utilization rate of Festuca ovina , Koeleria cristata under long-term soil drought treatment from June to September in 2010, and Poa pratensis was used as control. The results indicated that:(l) The total survival days of F. ovina , K. cristata populations were 18 to 22 days longer than P. pratensis, and the temporary wilting time were 14 to 17days, longer than P . pratensis. (2) The daily mean evapotranspiration rate of F. ovina and K. cristata populations were significantly lower than P. pratensis before temporary wilting, the daily mean evapotranspiration rate of two wild species were 60. 44%, 65. 38% (respectively, compared with the index of P. pratensis . (3) The critical levels of soil moisture content of F, ovina and K. cristata populations were significantly lower than P . pratensis when temporary wilting and permanent wilting happened, the wilting coefficients had no significant differences between F. ovina and K. cristata, but significantly lower than the index of P. pratensis respectively. The mean maximum soil moisture utilization rate of the two wild grass populations were 75. 26% , significantly higher than P. pratensis which was 64. 11%. (4) The maximum soil moisture utilization rate of different species were as follows: F. ovina > K. cristata>P. pratensis.%为了筛选出抗旱性较强的乡土草坪草种,在2010年6～9月期间利用盆栽试验研究了持续干旱胁迫对(落)草、羊茅与对照植物草地早熟禾种群的存活期、日均蒸腾量及其动态、萎蔫系数等指标的影响.结果表明:(1)在持续干旱胁迫下,与草地早熟禾相比,(落)草、羊茅种群总存活时间延长了18d～22d,出现暂时萎蔫症状时间推迟了14d～17d.(2)在植物发生暂时萎蔫之前,野生羊茅、(落)草种群的日均蒸腾量都显著低于草地早熟禾,二者的日均蒸腾量分别仅为草地早熟禾日均蒸腾量的60.44％、65.38％.(3)(落)草和羊茅种群发生暂时萎蔫、永久萎蔫时的土壤临界含水量均显著低于草地早熟禾,它们的平均最大土壤水分利用率为75.26％,也显著高于草地早熟禾.三种植物土壤水分最大利用率大小依次为:羊茅＞(落)草＞草地早熟禾.
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