NaCl胁迫下红砂愈伤组织中主要离子累积特征的研究

盐胁迫下植物对Na+、K+、Ca2+、Cl-的选择性吸收代表了植物对盐胁迫的适应性。以荒漠植物红砂为材料,研究不同浓度NaCl胁迫对红砂愈伤组织Na+、K+、Ca2+、Cl-含量的影响。结果表明,NaCl胁迫下红砂组织相对生长率随着盐浓度的增加先增加后下降,100mM处理时达到最大;K+、Ca2+含量下降,Na+和Cl-含量升高,变化幅度随NaCl浓度的增加而增大。红砂愈伤组织具有很强的耐盐能力,低浓度NaCl处理可促进愈伤组织的生长,对Na+、K+、Ca2+、Cl-的吸收选择性提高,有利于避免离子代谢紊乱,减轻NaCl胁迫的伤害;在较高浓度下盐胁迫会对植物的生长造成一定的抑制。可见,离子平衡是红砂组织耐盐性的重要机理之一。

Characters of Ions Accumulation in Reaumuria soongorica Callus under Salt Stress

The ability to selectively absorb Na+, K+, Ca2+, and Cl- represents the salt tolerance of plants. In this study we stressed desert plant Reaumuria soongorica callus on Murashige and Skoog medium with 0~250 mM NaCl solution for 14 days, and then Na+, K+, Ca2+, Cl- contents in tissue of R. soongorica were measured. The result showed that low concentration of NaCl was required to promote growth of R. soongorica, and the maximum relative growth rate of R. soongorica was observed at 100 mM NaCl, whereas higher concentrations of NaCl (200 and 250 mM) inhibited growth. Under NaCl stress the K+, Ca2+content in R. soongorica callus decreased and the Na+, Cl- content increased and the decrement and increment increased as the NaCl concentration increased. When NaCl concentration was low the selectivity of R. soongorica for Na+, K+, Ca2+, Cl- absorption and transport and the capacity of their ion accumulation strengthened, and this was conducive to avoiding the disorder of ion metabolism and alleviating the damage of NaCl stress.