Seasonal variations effect on antioxidant compounds and their role in the adaptation of some halophytes at Wadi Gharandal, Southwest Sinai

Abstract

The impact of seasonal variations on lipid peroxidation in terms of malondialdehyde (MDA) content, and contents of chlorophyll a and b, carotenoid, ascorbic acid content, proline content, glycine betaine content and total phenols content were assessed in seven halophytic representative species, viz., the shoot system of Halocnemum strobilaceum (Pall.) M. Bieb., Arthrocnemum macrostachyum (Moric.) K. Koch, Suaeda vermiculata Forssk. ex J. F. Gmel., Atriplex halimus L., Zygophyllum album L., Tammarix nilotica (Ehrenb.) Bunge, and Limonium pruinosum (L.) Chaz. Lipid peroxidation and glycine-betaine increased in summer, while chlorophyll a and b, and carotenoid decreased in all the species studied. During winter, the ascorbic acid content increased in all species, except in L. pruinosum, while total phenols content increased during summer except in Z. album. Positive correlations were recorded among carotenoids with chl. a, chl. b, ascorbic acid, proline and total phenols and also proline content with total phenols in the first four species belongs to Amaranthaceae. These results indicate that glycine betaine biosynthesis play a pivotal role in diluting the oxidative damage result in abiotic stress, especially in Amaranthaceae. Keywords: Correlation, Glycine betaine, Halophytes, Total phenols