NaCl胁迫对3种冷季型草坪草种子萌发和幼苗生长的影响

摘要

The seeds of 3 cool season turfgrasses including ryegrass (Lolium perenne),tall fescue (Festuca arundinacea) and Kentucky bluegrass (Poa pratensis) were used to study the seed germination and seedling growth under six levels of NaCl stress (0％,0.2％,0.4％,0.6％,0.8％ and 1.0％).The results showed that the germination potential,germination rate,relative germination potential,relative germination rate and germination index were inhibited with the increase of salt concentration.The relationship between the relative germination potential,relative germination and salt concentration was hyperbola correlation.The salt tolerance critical value of ryegrass,tall fescue and Kentucky bluegrass were 1.09％,1.11％ and 1.10％ respectively.The salt tolerance of fall fecue in seed germination stage was the best under salt stress,then followed by Kentucky bluegrass and ryegrass.The decrease of the biomass of Kentucky bluegrass seedlings was smaller than the others,and the increase of membrane permeability and proline content were increased significantly.From the combination of seed germination and seedling growth,compared with ryegrass and Kentucky bluegrass,tall fescue can be used as a better salt-tolerant cultivar.%以3种冷季型草坪草黑麦草(Lolium perenne)、高羊茅(Festuca arundinacea)和草地早熟禾(Poa pratensis)种子为材料,研究了6个NaCl浓度(0％、0.2％、0.4％、0.6％、0.8％、1.0％)处理下的种子萌发和幼苗生长指标.结果表明:随着盐浓度的升高,3种冷季型草坪草种子发芽势、发芽率、相对发芽势、相对发芽率和发芽指数均受到不同程度的抑制,盐浓度越高抑制越明显.3种冷季型草坪草的相对发芽势、相对发芽率与盐浓度均呈抛物线趋势.黑麦草、高羊茅和早熟禾的临界耐盐浓度分别为1.09％,1.11％和1.10％.高羊茅种子萌发期的耐盐性最好,其次,早熟禾和黑麦草.早熟禾幼苗生物量的下降幅度较小,细胞膜透性和脯氨酸含量的增加幅度较大,幼苗耐盐性表现为早熟禾＞高羊茅＞黑麦草.从种子萌发和幼苗生长状况综合分析,3种草坪草中高羊茅的耐盐性较好,可用于盐渍土草坪建植,有利于更好地发挥其耐盐和改良作用.