【摘要】 采用网室盆栽实验,研究了不同浓度海水(0,5%,10%,20%,30%和40%)处理下罗勒生长及生理特性的响应特征。结果表明,海水胁迫显著降低罗勒植株生长速率及地上部干物质积累量,而根系在30%海水处理下基本不受影响。高盐(30%和40%)处理显著促进罗勒植株可溶性糖和脯氨酸的积累、提高其叶片水分利用效率,但光合作用受到不同程度的抑制,光合速率的降低主要是由气孔因素所引起。海水胁迫下植株大量吸收Na+的同时伴随根系或茎部K+和Ca2+含量的显著降低,而叶片K+、Ca2+含量维持不变或显著增加。盐胁迫植株体内57.1%～64.6%的Na+积累在根系,而超过50%的K+和Ca2+分布在叶片中。海水胁迫明显降低罗勒植株K+/Na+和Ca2+/Na+,但所有盐处理的植株均维持较高的叶片K+/Na+和Ca2+/Na+,40%海水处理的叶片K+/Na+值仍高于3。研究结果表明,罗勒通过将Na+主要区隔于根系并维持叶片K+/Na+或Ca2+/Na+的稳定,以及在高盐环境下积累可溶性糖和脯氨酸进行渗透调节来适应不同浓度的海水胁迫。更多还原

【Abstract】 Basil(Ocimum basilicum) seedlings were subjected to 0,5%,10%,20%,30% and 40% seawater under netting house conditions.Increasing seawater concentration led to considerable reduction in plant growth rate and dry mass accumulation.However,root growth was not affected even by treatment with 30% seawater.High salinity(30% and 40% seawater) caused significant increases of soluble sugar and proline contents as well as leaf water use efficiency,whereas photosynthesis was inhibited mainly due to stomatal restriction.Accumulation of Na+ was correlated with a decline of Ca2+ and K+ in stems,roots or both.However,contents of K+ and Ca2+ in leaves increased or remained relatively unchanged with increasing salt levels.In plants stressed by salinity,Na+ were partitioned mainly in roots(57.1%-64.6% of the total) and more than 50% of the K+ and Ca2+ were stored in leaves.In addition,seawater stress decreased the K+/Na+ and Ca2+/Na+ in this species,although the higher K+/Na+ and Ca2+/Na+ were observed in leaves rather than in roots and stems.The K+/Na+ was greater than three even when subjected to 40% seawater.These results suggest that salt tolerance of basil plants might be associated with the compartmentalisation of Na+ in roots and the balance of K+,Na+ and Ca2+ in leaves as well as the osmotic adjustment with soluble sugar and proline under conditions of high salinity.更多还原