Abstract: The drought resistant characteristics of four species of Festuca L.at seedling stage were studied through successive drought,repeated drought and rewatering,and their drought-resistance order was compared through integrated appraisal,and the identification indices of drought resistance of Festuca species were given.The results show that the leaf tissue water content(TWC),relative water content(RWC),and soil relative water content(SRWC)decreased significantly(P<0.05),while cell membrane permeability(REC),praline(PRO)content,malondialdehyde(MDA)content,and chlorophyll content increased significantly under the successive drought stess(P<0.05);all of the indices recovered to different degrees after rewatering.F.arundincea cv.Fawn had the lowest(40%)survival rate,F.kryloviana Reverd.and F.kirilovii Steud.the medium(50%),and F.sinensis Keng.the highest(80%)under repeated drought stress.Their drought-resistance order at seedling stage was F.sinensis>F.krylovina>F.kirilovii>F.arundinacea.Leaf PRO,RWC,and chlorophyll a content could be used as the preferred physiology and biochemistry indices for the drought resistance identification of Festuca species and SRWC,leaf withering rate,and survival rate the reliable biological identification indices.

Key words: Festuca L., Seedlings stage, Drought resistance

摘要： 对羊茅属(Festuca L.)4种牧草苗期幼苗在连续干旱、反复干旱和复水后的抗旱性特征进行研究,并通过综合评定,比较4种材料的抗旱性强弱,提出了羊茅属牧草抗旱性鉴定的指标。结果表明,连续干旱胁迫下,羊茅属各牧草叶片组织含水量、相对含水量、土壤含水量显著降低(P<0.05),而细胞膜透性、脯氨酸、丙二醛、叶绿素显著增加(P<0.05);复水后各指标均有不同程度的恢复。反复干旱后,法恩苇状羊茅成活率最低(40%左右),西北羊茅和毛稃羊茅次之(50%左右),中华羊茅最高(80%左右)。经评定4种牧草苗期抗旱性顺序为:中华羊茅>西北羊茅>毛稃羊茅>法恩苇状羊茅。脯氨酸、相对含水量、叶绿素a可作为羊茅属牧草抗旱性鉴定首选生理生化指标;土壤相对含水量、叶片枯死率、牧草成活率可作为羊茅属牧草生物学鉴定的可靠指标。

关键词: 羊茅属, 苗期, 抗旱性