Vasilakoglou Ioannis, Dhima Kico, Giannakoula Anastasia, Dordas Christos, Skiada Vasiliki, Papadopoulou Kalliope
Department of Agriculture-Agrotechnology, University of Thessaly, 415 00 Larissa, Greece.
Department of Agriculture, International Hellenic University, 574 00 Echedoros, Greece.
Plants (Basel). 2021 Feb 4;10(2):299. doi: 10.3390/plants10020299.
Barley ( L.) exhibits great adaptability to salt tolerance in marginal environments because of its great genetic diversity. Differences in main biochemical, physiological, and molecular processes, which could explain the different tolerance to soil salinity of 16 barley varieties, were examined during a two-year field experiment. The study was conducted in a saline soil with an electrical conductivity ranging from 7.3 to 11.5 dS/m. During the experiment, a number of different physiological and biochemical characteristics were evaluated when barley was at the two- to three-nodes growing stage (BBCH code 32-33). The results indicated that there were significant ( < 0.001) effects due to varieties for tolerance to salinity. Carbon isotopes discrimination was higher by 11.8% to 16.0% in salt tolerant varieties than that in the sensitive ones. Additionally, in the tolerant varieties, assimilation rates of CO and proline concentration were 200% and up to 67% higher than the sensitive varieties, respectively. However, in sensitive varieties, hydrogen peroxide and lipid peroxidation were enhanced, indicating an increased lipid peroxidation. The expression of the genes , , and did not differ among barley varieties tested. This study suggests that the increased carbon isotopes discrimination, increased proline concentration (play an osmolyte source role), and decreased lipid peroxidation are traits that are associated with barley tolerance to soil salinity. Moreover, our findings that proline improves salt tolerance by up-regulating stress-protective enzymes and reducing oxidation of lipid membranes will encourage our hypothesis that there are specific mechanisms that can be co-related with the salt sensitivity or the tolerance of barley. Therefore, further research is needed to ensure the tolerance mechanisms that exclude NaCl in salt tolerant barley varieties and diminish accumulation of lipid peroxides through adaptive plant responses.
大麦（L.）由于其丰富的遗传多样性，在边缘环境中对盐分具有很强的适应性。在一项为期两年的田间试验中，研究了16个大麦品种在主要生化、生理和分子过程上的差异，这些差异可以解释它们对土壤盐分的不同耐受性。该研究在电导率为7.3至11.5 dS/m的盐渍土壤中进行。在试验期间，当大麦处于二至三叶期（BBCH编码32 - 33）时，评估了许多不同的生理和生化特征。结果表明，品种间在耐盐性方面存在显著（<0.001）差异。耐盐品种的碳同位素歧视比敏感品种高11.8%至16.0%。此外，在耐盐品种中，CO同化率和脯氨酸浓度分别比敏感品种高200%和高达67%。然而，在敏感品种中，过氧化氢和脂质过氧化作用增强，表明脂质过氧化增加。所测试的大麦品种中，基因、和的表达没有差异。本研究表明，碳同位素歧视增加、脯氨酸浓度增加（起渗透调节剂来源的作用）以及脂质过氧化减少是与大麦耐土壤盐分相关的特征。此外，我们发现脯氨酸通过上调应激保护酶和减少脂质膜氧化来提高耐盐性，这将支持我们的假设，即存在与大麦的盐敏感性或耐受性相关的特定机制。因此，需要进一步研究以确定耐盐大麦品种中排除NaCl的耐受机制，并通过适应性植物反应减少脂质过氧化物的积累。
