两种不同耐盐大麦根际中离子的分布特征

DISTRIBUTION CHARACTERISTICS OF IONS IN THE RHIZOSPHERE OF TWO BARLEY VARIETIES WITH DIFFERENT SALINITY TOLERANCE

选用耐盐性较强的大麦滩引5号(T)和盐敏感大麦CTl6(S),用根袋法研究了大麦根际中各种盐分离子的分布特征及动态变化。T大麦土体的pH高于S大麦,根际则相反。与非根际比较,T大麦根际土壤中除K^+离子亏缺外,Na^+、Ca^(2+)、Mg^(2+)、SO_4^(2-)、Cl^-及HCO_3^-离子均富集;而S大麦根际土壤中K^+和Na^+离子亏缺,其它离子则不同程度地富集,但除HCO_3^-离子外,亏缺或富集的程度均不及T大麦显著。土壤中本身的含盐量和生育期会影响离子的分布,并与大麦对盐分离子的吸收有关。

The distribution characteristics and dynamic changes of salt ions in the rhizosphere of barley plants were investigated in rhizobag experiment, with salt tolerant variety Taiying No. 5 (T) and salt sensitive variety CT16 (S). It was found that pH value in nonrhizosphere of T barley was higher than that of S barley, while in rhizosphere, the contrary result was observed. Except for the K^+ depletion, Na^+, Ca^(2+), Mg^(2+), SO_4^(2-), Cl^- and HCO_3^-ions were accumulated in the rhizosphere of T barley compared to those of non-rhizosphere. For S barley, K^+ and Na^+ ions were depleted whereas other ions were accumulated to certain degree. But for HCO_3^- ion, the degree of depletion or accumulation of other ions was lower for S barley as compared with T barley. The original content of soil salt ions and growth stage of barley plant would affect the distribution of ions at barley root-soil interface and relate to the salt ion absorption of barley plant.