Etude de l’effet de la salinité sur la germination et l’anatomie de Peganum harmala L.

Abstract

A number of abiotic factors are known to affect seed germination and plant distribution in natural habitats. In this study, the effect of saline solutions at different concentrations (0 g/L, 2.5 g/L, 5 g/L, 10 g/L) was evaluated on the germination and development of Peganum harmala L. seeds, as well as on several physiological parameters (final germination rate (G%), germination speed (VG%)), morphological parameters (number of leaves (NL), stem length (SL), root length (RL), fresh mass and dry mass (FM and DM), and anatomical features. The results showed that treatment with different saline concentrations, compared to the control, led to a decrease in physiological parameters (G% and VG %). Thus, increasing NaCl concentration does not delay germination, but it does reduce the germination rate and speed. A decline was also observed in morphological parameters: NL, SL, RL, FM, and DM. It is concluded that the higher the concentration, the more the parameters decrease, particularly at the highest concentration (C3). Anatomical analysis of leaf and root sections revealed visible modifications. In the roots, there was a narrowing of vascular tissues and disruption of cellular organization. In the leaves, salinity caused epidermal thinning, deformation of the palisade parenchyma, and a reduction in cell density. These alterations limit conduction, photosynthesis, and the plant's resistance. It is concluded that Peganum harmala L. is a salt-tolerant (halophytic) plant.