The Comparative Study of Antioxidants in Plants of East Georgian Arid Habitats (Yagludja and Kvernaqi hills)
The preliminary report of 2021 of the world meteorological organization on the climate global situation clears its negative changes all over the world. Especially disturbing is the temperature rise, accompanied by hot waves, forest fires, intensive melting of the ice cover, and other undesirable aftereffects. Climate warming significantly increases the chances of dying of many plant species. Drought resistant plants have the highest potential of adaptation to increased temperature and water deficiency. Thus, knowledge of their biology will be especially important in deserted regions restoration. The nonspecific mechanisms of resistance, especially antioxidant system, are concerned as one of the leading in plants drought resistance. The presented study aimed the comparative study of the indices of antioxidant system (ascorbic acid, tocopherol, carotenoids, anthocyanins, soluble phenols, proline, total proteins and soluble carbohydrates, as well as the activity of catalase, peroxidase, nitrate reductase and the total antioxidant activity in percents of inhibtion) of drought resistant species-Astragalus microcephalus Willd. (Astracantha microcephala (Willd.) Podlech)-goat’s thorn,Theucrium polium L-felty germander, Euphorbia seguieriana Neck- spurge, Capparis spinosa L-caper bush, Paliurus spina-christi Mill–Christ’s thorn, growing in two different arid habitats of the East Georgia (Iagludja and Kvernaqi hills).
The defence mechanisms of the antioxidant system appeared to be partially different in one and the same species of various habitats, as well as in different species of the same habitats. Activation of phenolic substances and anthocyanins synthesis against extreme conditions of both habitats (water deficiency, high temperature and intensive irradiation) was common for all tested species. Additionaly, activation of peroxidase in Kvernaqi species and intensive accumulation of soluble carbohydrates in Iagludja plants was mentioned.