Ameliorative Impact of an Extract of the Halophyte Arthrocnemum macrostachyum on Growth and Biochemical Parameters of Soybean Under Salinity Stress

A pot experiment was carried out to study the ameliorative role of foliar application of an extract of the halophyte Arthrocnemum macrostachyum ( A. macrostachyum) on soybean ( Glycin max L.) plants grown under salinity stress (0, 75, and 150 mM NaCl). Growth traits, content of photosynthetic pigments, osmolytes, ascorbic acid and total phenol, oxidative damage, and proteins pattern were determined. Growth parameters of soybean plants grown under both saline regimes (75 and 150 mM NaCl) were reduced except for the response to the foliar application of A. macrostachyum extract in either stressed or non-stressed plants. Foliar application of A. macrostachyum extract reinforced the photosynthetic pigment, soluble sugars, and soluble proteins content. Besides, it also minimized the negative impacts of salinity on soybean plants by decreasing the content of malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2 ). The results herein showed that the plant water extract and their interactions in the two NaCl levels increased the proline, total free amino acids, total phenols, and ascorbic acid content. Protein patterns in soybean leaves indicated protein expression suppression in soybean plants irrigated with 150 mM NaCl. The magnitude of suppression caused by the saline level was enhanced by using A. macrostachyum extract. The findings of this study indicate that the use of an extract of the halophyte A. macrostachyum can be considered as an unconventional and novel tool in the mitigation of salinity stress.