3种冷季型草坪草对短期盐胁迫的生长响应

摘要

The growth characters of 3 cool season turfgrasses [ryegrass (Lolium perenne),tall fescue (Festuca arundinacea) and kentucky bluegrass (Poa pratensis)] were studied under short-term NaCl concentrations (0％,0.2％,0.4％,0.6％,0.8％,1％) in pot experiments.The results showed that tudgrass quality and wilting coefficient decreased with NaCl concentration increasing,and the growing of 3 turfgrasses were severely inhibited under salt stress.Leave relative water content of ryegrass,tall rescue and kentucky bluegrass decreased by 12％,9％ and 4％,respectively,compared with control.The effects of NaCl stress on underground biomass of 3 turfgrasses were greater than that on boveground biomass.There was a positive correlation between leaf coverage and biomass.Kentucky bluegrass has the highest salt resistance.Proline content and relative electrical conductivity of 3 turfgrasses under NaCl concentration of 1.0％ reached the maximum.K+ content in leaf and in root reduced with NaCl concentration increasing,but Na+ content in leaf and in root increased.Salt tolerance was in order of kentucky bluegrass＞tall fescue＞ryegrass.%采用盐水灌溉的方法,比较了3种冷季型草坪草黑麦草(Lolium perenne)、高羊茅(Festuca arundinacea)和早熟禾(Poa pratensis),在短期不同盐胁迫条件下(NaCl质量分数分别为0％,0.2％、0.4％、0.6％、0.8％、1％)生长特性.结果表明:3种草坪草的外观质量和叶片萎蔫系数总体上变化一致,随着盐浓度的不断增加而降低,生长受到严重抑制.黑麦草、高羊茅和早熟禾的叶片相对含水量比对照分别下降了12％,9％和4％,早熟禾的下降幅度最低.盐胁迫对根系生物量的影响大于对地上部分.绿叶盖度与植物生物量呈显著的正相关,早熟禾具有较高的抗盐性.3种草坪草在盐浓度为1.0％下叶片脯氨酸和电导率含量均达到最大值,早熟禾叶片电导率最高.叶片和根系K+含量随着盐浓度的提高而逐渐降低,Na+含量逐渐升高.根据短期盐胁迫各生长指标的结果,3种草坪草的抗盐能力依次为早熟禾＞高羊茅＞黑麦草.