摘要
用不同盐分浓度的NaCl中性盐对羊草进行胁迫,探讨在土壤脱湿过程中,NaCl胁迫对羊草生长和矿质元素吸收分配的影响。结果表明,当土壤溶液NaCl浓度小于125mmol/L(土壤总盐小于0.34%)时,盐分胁迫对羊草株高、根长、干物质积累量和相对生长率(RGR)无显著影响,且根系的钾钠吸收选择性和运输选择性随盐度处理水平的增加而增强。但当NaCl浓度超过225mmol/L(土壤总盐大于0.53%)后,其株高、根长、干物质积累量和相对生长率(RGR)随盐度增加而显著降低(P<0.05),根系的钾钠吸收选择性和运输选择性也随盐度处理水平的增加而逐渐减弱。NaCl胁迫条件下,羊草对K、Ca的比吸收率(SAR)降低,茎叶K、Ca含量随盐度的增加显著减少(P<0.05),Na、Cl含量则均随盐度的增加而显著提高,植株K/Na降低。羊草茎叶的盐分离子(Na+、Cl-)含量与相对生长率(RGR)之间呈显著的负相关关系。
Leymus chinensis was exposed to different content of NaCl (25,75,125,175,225,275,325 mmol/L) for 50 days in drying soil. The influence of NaCl stress on growth and mineral absorption was studied by using simulating experiment. The results showed that, length of root, biomass, relative growth rate and KNa selectivity ratios (Sk, Na) were reduced significantly with salinity from 225 mmol/L up to 325 mmol/L NaCl. Salt stress decreased the specific absorption rate of K and Ca, the content of K and Ca, and K/Na ratio in plant. With salt increasing, the specific absorption rate of Na and Cl, and the content of Na and Cl in Leymus chinensis increased notably. There is a negative relation between relative growth rate and the content of Na and Cl in Leymus chinensis.
出处
《草业学报》
CSCD
2003年第2期40-45,共6页
Acta Prataculturae Sinica
基金
国家自然科学基金项目"盐渍土壤-牧草系统盐分与养分离子交互作用研究"(编号:39800110)。
