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Anatomically distinct representatives of Cactaceae Juss. family have different response to acute heat shock stress

2018; Elsevier BV; Volume: 242; Linguagem: Inglês

10.1016/j.flora.2018.03.014

1618-0585

N. V. Nuzhyna, Kateryna Baglay, A. V. Golubenko, Oleh Lushchak,

Plant responses to water stress

In order to escape extreme environmental conditions plants have developed different survival strategies. The study of plant response to high temperatures is especially interesting in representatives of varied cacti families that have to resist big temperature oscillations. In the present study plants of Aylostera, Echinocactus and Mammillaria genera were exposed to temperatures of 40 or 50 °C for 3 h and peroxidase and superoxide dismutase activity, photosynthetic pigments and flavonoids concentration, and lipid peroxide oxidation level in the stem were determined. Plants with different anatomical structure showed distinct patterns of response to high temperature. Plants of Echinocactus grusonii proved the highest drought and heat resistant with strong antioxidant response and the most expressed xerophytic features of anatomical structures (epidermis and cuticle thickening, calcium oxalate accumulation, water-storage tissue development). Heat stress induced a quick increase of peroxidase activity and flavonoid concentration in this species. Relative heat resistance (40 °C) in Mammillaria bocasana is also facilitated by increased flavonoid concentration, chlorophyll a and carotenoid concentration and also high superoxide dismutase activity under normal conditions. We conclude that the development of antioxidant reactions depends on anatomical protection of plants. More effective anatomical conformation to the stress conditions may be accompanied by rapid response to stress at the antioxidant biochemical level. Less effective protection at the anatomical level to hyperthermia is accompanied by the presence of a larger activity of antioxidant enzymes in conditions without short-term high-temperature stress. Plants which do not possess these qualities, Aylostera flavistyla in particular, suffer more from short-term high-temperature stress.