Effect of Salinity Stress on Seedling Development of Different Ecotypes of the Model Legume Medicago truncatula

Abstract

For the analysis of seedling growth under salinity stress, it will be useful to study root growth in comparison to shoot elongation under salt stress. In this study, we assessed the variability of eleven ecotypes of M. truncatula under salt stress (137 mM) of NaCl compared to the control. Several studies are focalised in root growth and development because it is the most sensitive part of the plant and controls rapid transmission information to other plant parts. In order to assess the level of root sensitivity, we measured the shoot length to root length ratio. The Results showed that Tru 131 ecotype, with a high ratio (Root more vigorous than shoot) is more tolerant to salinity stress than the sensitive ecotypes that had a low ratio. We consider that the most tolerant Algerian ecotype Tru 11 (Tru 131) can be cultivated in saline and semi-arid areas in Algeria and Mediterranean regions in order to improve the legumes productivity and ameliorate the nitrogen fixation.

Physiological and biochemical characterization of rootlets response to salt stress in two <i>Medicago truncatula</i> Gaertn. ecotypes

“…The investigation of the effect of salt stress on seedling development of four genotypes of M. truncatula, showed that the root growth of Tru 131 genotype is more resistant to salinity stress under different concentration of NaCl (0 mM, 68 mM, 102 mM and 137 mM) than Jemalong, the sensitive one (Amouri et al 2014). In addition, the assessment of the variability between eleven ecotypes of M. truncatula under salt stress (137 mM of NaCl), showed that the tolerant ecotype Tru 131 had the best root growth compared to the sensitive ecotypes like Jemalong (Amouri 2015). In the other hand, we observed that salt stress decreased the water potential of the roots, much in the tolerant genotype Tru 131 compared to the susceptible genotype Jemalong.…”

Trait based assessment in seedling stage of rice for salinity tolerance

“…When root to shoot ratio on weight basis was analyzed, an increase in mean root to shoot ratio under salinity stress was observed (Fig 2). Salt tolerant genotypes has generally higher root to shoot ratio compared to susceptible one and this trait can be used for screening genotypes for tolerance to abiotic stress (Amouri, 2015;Thomas et al,2020).…”