Elytrigia elongata, a rhizomatous and sparse-type perennial herb of the Triticeae tribe, with stronger drought and salt tolerance, is an important wild genetic resource for wheat variety improvement. However, no precise information about seed germination and biochemical responses of this species to drought, salinity and mixed saline–alkaline stresses is available. Hence, this experiment was conducted to investigate the effects of three abiotic stresses on seed germination and physiological characteristics of two E. elongata accessions. The results showed that drought and mixed saline–alkaline stresses impair seed germination and bud seedling growth of E. elongata. However, seed germination and bud seedling growth were promoted by 50 mmol/L, but inhibited by 100–200 mmol/L salinity treatments. The malondialdehyde (MDA) content was increased and the activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in the bud seedlings were significantly increased (p <.05) with increasing osmotic stress from 0 to −0.4 MPa, and salinity and mixed saline–alkaline from 0 to 150 mmol/L, but reduced at −0.75 MPa osmotic stress and 200 mmol/L salinity and mixed saline–alkaline stresses. Under the same salinity and mixed saline–alkaline treatment, the activities of SOD and CAT of EE030 were higher than those of EE024 except in 200 mmol/L salinity treatment; however, the MDA content of EE030 was lower than that of EE024, except in 150 mmol/L salinity treatment. In conclusion, the results of this study demonstrated that E. elongata seeds are more tolerant to salinity stress than to drought and mixed saline–alkaline stresses, and EE030 seed are more tolerant to three abiotic stresses than are the seeds of EE024.

中文翻译：

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两种 Elytrigia elongata 种质暴露于非生物胁迫下的种子萌发和生化反应

Elytrigia elongata是小麦科多年生疏根草本植物，具有较强的耐旱耐盐性，是小麦品种改良的重要野生遗传资源。然而，没有关于该物种对干旱、盐度和混合盐碱胁迫的种子萌发和生化反应的准确信息。因此，本实验旨在研究三种非生物胁迫对两种E. elongata种质种子萌发和生理特性的影响。结果表明，干旱和盐碱混合胁迫会损害E. elongata 的种子萌发和芽苗生长. 然而，50 mmol/L 可促进种子萌发和芽苗生长，但受 100-200 mmol/L 盐度处理的抑制。丙二醛（MDA）含量增加，芽苗中超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和过氧化物酶（POD）活性显着增加（p <.05) 随着渗透胁迫从 0 增加到 -0.4 MPa，盐度和混合盐碱从 0 增加到 150 mmol/L，但在 -0.75 MPa 渗透胁迫和 200 mmol/L 盐度和混合盐碱胁迫下降低. 在相同盐度和盐碱混合处理下，除200 mmol/L盐度处理外，EE030的SOD和CAT活性均高于EE024；然而，EE030 的 MDA 含量低于 EE024，除了在 150 mmol/L 盐度处理。总而言之，本研究结果表明E. elongata种子比干旱和盐碱混合胁迫更能耐受盐分胁迫，EE030 种子比 EE024 种子更能耐受三种非生物胁迫。