地毯草耐盐浓度梯度筛选与临界盐浓度研究

以地毯草(Axonopus compressus)为对象，利用水培法进行耐盐鉴定，初步研究不同盐浓度对地毯草坪用品质、叶色和枯黄率的影响，并对地毯草耐盐性进行了评价。结果表明，不同的处理之间存在显著或极显著性差异，在低浓度处理下（0～120 mmol·L-1），叶色和坪用品质得分6分以上；而在高浓度处理下（140～180 mmol·L-1），景观价值低于6分。叶片枯黄率与之正好相反，在低浓度下（0～140 mmol·L-1），枯黄率较低；而在高浓度下（160～180 mmol·L-1），枯黄率超过50%，从而导致地毯草草坪观赏价值过低。通过建立回归方程，以枯黄率50%作为确定存活的临界值指标，求得地毯草具有盐半致死临界浓度为141 mmol·L-1。

Study on screening of salt concentration gradient and critical concentration on Axonopus compressus

In the present study,we took Axonopus compressus as the main research object,aiming to evaluate its ability of salt resistance.The turf quality,leaf color,and leaf firing percentage of carpet grass in different salt concentrations by hydroponics experiment were examined.The results of this study showed that there were significant or very significant differences among different treatments of salt concentration.Under the treatment of low salt concentration(0-120 mmol·L-1),the scores of leaf colour and turf quality were both higher than six,meanwhile,under the treatment of high salt concentration(140-180 mmol·L-1),the scores were lower than six.However,leaf firing showed a different pattern,which has a lower percentage at low concentration(0-140 mmol·L-1) than that at the high concentration(160-180 mmol·L-1).Taking yellow rate dropping at 50% as an index,we built a regression equation and found that the critical salt concentration of NaCl to A.compressus was 141 mmol·L-1.