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.