Yildiztugay Evren, Ozfidan-Konakci Ceyda, Kucukoduk Mustafa, Duran Yagmur
Department of Biology, Selcuk University, Faculty of Science, Selcuklu, 42031, Konya, Turkey.
Department of Molecular Biology and Genetics, Faculty of Science, Necmettin Erbakan University, Meram, 42090, Konya, Turkey.
Bot Stud. 2014 Dec;55(1):6. doi: 10.1186/1999-3110-55-6. Epub 2014 Jan 17.
Sphaerophysa kotschyana Boiss. is naturally distributed in overly salty regions. The key to the completion of the life cycles of S. kotschyana in harsh saline soils may be hidden in changes of its osmo-protectants, but there is currently no information about the interaction between osmotic adjustment and water relations in adaptation to saline conditions. The aim of this article was to determine growth, relative growth rate (RGR), relative water content (RWC), osmotic potential (Ψ), photosynthetic efficiency (F/F), thiobarbituric acid-reactive substances (TBARS) and osmo-protectant contents [proline (Pro), choline (Cho) and glycine betaine (GB)] in S. kotschyana leaves and roots exposed to 0, 150 or 300 mM NaCl for 7 and 14 d (days).
The results clearly showed that the reductions in growth, RWC, F/F, RGR and Ψ were more pronounced at 300 mM, especially after 14 d. In the same group, the highest increase in TBARS was recorded in roots (126%) and leaves (31%). The induction at 150 mM was not as high. Therefore, roots appear to be the most vulnerable part of this plant. Moreover, S. kotschyana was able to withstand short-term low salinity.
The osmo-protectant accumulation in S. kotschyana as a salinity acclimation or adaptation was sufficient for toleration of low salt concentration (150 mM). In contrast, the plants exposed to the highest NaCl concentration (300 mM) were not able to maintain the ability to prevent water loss because of further decrease in root/shoot ratio of fresh weight (FW) and dry weight (DW), RWC and RGR.
科氏苦马豆（Sphaerophysa kotschyana Boiss.）自然分布于盐分过高的地区。在恶劣的盐渍土壤中完成科氏苦马豆生命周期的关键可能隐藏在其渗透保护剂的变化中，但目前尚无关于渗透调节与水分关系在适应盐渍条件下相互作用的信息。本文旨在测定暴露于0、150或300 mM氯化钠7天和14天的科氏苦马豆叶片和根中的生长、相对生长速率（RGR）、相对含水量（RWC）、渗透势（Ψ）、光合效率（F/F）、硫代巴比妥酸反应性物质（TBARS）和渗透保护剂含量[脯氨酸（Pro）、胆碱（Cho）和甘氨酸甜菜碱（GB）]。
结果清楚地表明，在300 mM时生长、RWC、F/F、RGR和Ψ的降低更为明显，尤其是在14天后。在同一组中，根（126%）和叶（31%）中TBARS的增加最为显著。150 mM时的诱导作用没有那么高。因此，根似乎是这种植物最脆弱的部分。此外，科氏苦马豆能够耐受短期低盐度。
科氏苦马豆中渗透保护剂的积累作为盐度驯化或适应足以耐受低盐浓度（150 mM）。相比之下，暴露于最高氯化钠浓度（300 mM）的植物由于鲜重（FW）和干重（DW）的根/茎比、RWC和RGR进一步降低，无法维持防止水分流失的能力。
