四种暖季型禾草对水分胁迫的生理响应

为筛选出西南地区适宜种植的暖季型禾草种类，以毛花雀稗（Paspalum dilatatum Poir）、小毛花雀稗（Paspalum urville S.）、柳枝稷（Panicum. virgatum L.）和非洲狗尾草（Setaria anceps）为材料，采用盆栽控水方法，研究干旱胁迫对植物叶片相对含水量、光合参数、游离脯氨酸含量和丙二醛含量等生理生化指标的影响。结果表明，随干旱时间的延长，几种暖季型禾草都表现出相对含水量下降、光合速率和蒸腾速率下降、气孔导度下降、游离脯氨酸含量上升、丙二醛含量上升等特征，但几种暖季型禾草的反应及复水后各指标的恢复能力各不相同。通过上述6项指标综合评价后初步认为，几种暖季型禾草的抗旱性顺序为柳枝稷＞小毛花雀稗＞非洲狗尾草＞毛花雀稗。

Physiological Responses to Drought Stress of Warm-Season Forage Grasses

In order to evaluation the effects of drought stress, relative water content, photosynthetic parameter, content of free praline and content of malondiadiadehyde of four forage grasses were analyzed, with the experiment on pot culture with water stress in southwest area. The results indicated that with continuous lasting of drought time, four warm-season forage grasses all displayed the similar physiological characteristics, i.e. decreasing of relative water content, photosynthetic rate, transpiration rate and cond, increasing of content of free praline and malondiadiadehyde. However, the four warm-season forage grasses showed different physiological reaction to the drought stress, and different recovery abilities after re-irrigation. Through comparing the indexes and giving a comprehensive appraisal, the results indicated that the order of drought of forage grasses was Panicum . virgatum L.＞ Paspalum urville S. ＞ Setaria anceps＞ Paspalum dilatatum Poir.