Jouve L, Hoffmann L, Hausman J-F
CRP-Gabriel Lippmann, CREBS Research Unit, Luxembourg.
Plant Biol (Stuttg). 2004 Jan-Feb;6(1):74-80. doi: 10.1055/s-2003-44687.
Excess salt in the soil solution affects the plant either through osmotic or ionic effects. Poplar trees, as fast growing pioneer tree species, are thought to be potential suitable candidates for afforestation on saline soils. Osmotic and oxidative stress induced by salinity could be reduced by the production and accumulation of compatible solutes and osmoprotectants in the plant. In this respect, metabolites of this type could be interesting markers for the improvement of salt stress tolerance in breeding programmes. Results have shown that Populus tremula was able to cope with up to 150 mM NaCl without any effect on plant survival. During stress application, the endogenous level of malondialdehyde did not vary significantly between the treatments, indicating that the level of lipid peroxidation was similar in the control and in the stressed plants. However, proline, spermine, sucrose, mannitol, and raffinose levels increased temporarily or throughout the salt treatment. All these molecules are more or less closely related to antioxidant or osmoprotectant mechanisms during stress, suggesting a key role for these compatible solutes, osmoprotectants, and their metabolism for salt stress resistance. The accumulation of free proline, sucrose and mannitol, and the transitory increase in spermine level observable during low and high NaCl application must be considered as general salt stress reaction markers.
土壤溶液中过量的盐分通过渗透作用或离子效应影响植物。杨树作为速生先锋树种，被认为是盐碱地造林的潜在适宜候选树种。盐分诱导的渗透胁迫和氧化胁迫可通过植物体内相容性溶质和渗透保护剂的产生和积累来减轻。在这方面，这类代谢产物可能是育种计划中提高盐胁迫耐受性的有趣标记物。结果表明，欧洲山杨能够耐受高达150 mM的NaCl，且对植物存活没有任何影响。在施加胁迫期间，各处理间丙二醛的内源水平没有显著变化，这表明对照植株和受胁迫植株的脂质过氧化水平相似。然而，脯氨酸、精胺、蔗糖、甘露醇和棉子糖水平在盐处理期间暂时升高或持续升高。所有这些分子在胁迫期间或多或少都与抗氧化或渗透保护机制密切相关，这表明这些相容性溶质、渗透保护剂及其代谢在抗盐胁迫中起关键作用。在低浓度和高浓度NaCl处理期间观察到的游离脯氨酸、蔗糖和甘露醇的积累以及精胺水平的短暂升高，必须被视为一般的盐胁迫反应标记物。
