藜异型性种子后代植株盐响应生理机制

种子异型性是植物适应异质生境的重要策略,异型性对后代植株的影响值得深入研究。以具有种子异型性的荒漠植物藜为材料,测定了异型种子后代植株在不同浓度(0,50,300 mmol/L)Na Cl胁迫下的表型及与耐盐相关的生理指标变化,探讨了异型种子后代植株之间对盐胁迫生理响应机制的差异。结果显示,褐色种子后代植株在各浓度盐胁迫下的表型(株高、分枝数)均优于黑色种子。对其生理指标测定结果显示,褐色种子植株除电导率显著低于黑色种子植株外,氧化损伤指标(氧自由基、丙二醛含量)及抗氧化酶(SOD、CAT、POX)活性、抗氧化剂(Car、As A)含量、渗调物质(可溶性糖、脯氨酸、甜菜碱)含量等在两者之间无明显差异。研究结果暗示,藜异型性种子后代植株的早期生长表型在盐胁迫下所产生的差异可能是由种子胚的大小及萌发快慢差异所导致,而这种差异并未引起盐胁迫下两种植株抗氧化系统响应的差异。

Physiological responses to salt stress of plants derived from heteromorphic seeds of Chenopodium album

Seed heteromorphism is an important strategy of plants for adapting to heterogeneous environments, and the effect of heteromorphism on the descendant is worth studying in detail. In the present study, a comparison of the physiological responses to salinity stress between the brown seed plant and black seed plant of Chenopodium album (Imbikicane) was performed by analyzing the effects on growth and physiological changes under different concentrations (0, 50, and 300 mmol/L NaCl) of salt stress. The results indicated that the growth characteristics (plant height and branch number) of plants from the brown seed performed better than those of plants from the black seed under various salt concentrations. In addition to electrolyte leakage, for which the black seed plant had significantly higher values than the brown seed plant, all salt tolerance-related indices, such as oxidative damage parameters (O₂^.-, MDA), antioxidants (Car, AsA), antioxidant enzymes (SOD, CAT, POX), and osmolytes (Soluble sugar, Pro, and GB) showed no significant difference between two types of plants. This suggests that the difference between early growth characteristics of the two types of plants might be caused by diverse differences in the seed embryo size and germination speed, which did not to apply to the antioxidative system.