土壤脱水过程中NaCl胁迫对羊草水分利用效率的影响

Effect of NaCl Stress on Water Use Efficiency ofAneurolepidium Chinense in Drying Soil

通过室内模拟实验研究了土壤脱水过程中NaCl胁迫对羊草生长和水分利用的影响。结果表明,在土壤脱水过程中,羊草株高、根长、干物质积累量、相对生长率(RGR)和蒸散量随盐度增加显著降低。羊草生长的临界土壤溶液NaCl浓度为253mmol/L,临界土壤含盐量为0.60%。在低盐处理(NaCl25～225mmol/L,总盐0.17～0.53%)时,增加盐度,水分利用效率(WUEET)、钾钠吸收选择性和运输选择性有显著提高;而在高盐(NaCl275～325mmol/L,0.63～0.73%)条件下,随盐度的增加,水分利用效率(WUEET)、钾钠吸收选择性和运输选择性降低。

The influence of NaCl stress on growth and water use efficiency of Aneurolepidium Chinense was studied using simulating experiment in drying soil. The results showed that, with salt increasing, the height and length of root, biomass, relative growth rate and Evapotranspiration were reduced greatly in drying soil. The salinity critical value of NaCl concentration in drying soil was 253 mmol/L for Aneurolepidium Chinense and the total salt content was 0.60%. Water use efficiency and K-Na selectivity ratios (SK, Na) increased with salinity from 25 mmol/L up to 225 mmol/L NaCl, and then they decreased at high salt level (NaCl 275～325 mmol/L).