Original scientific paper

https://doi.org/10.2478/botcro-2014-0008

Physiological and biochemical responses of Fibigia triquetra (DC.) Boiss. to osmotic stress

Valerija Vujčić ; Department of Biology, Faculty of Science, University of Zagreb, Rooseveltov trg 6, HR-10000 Zagreb, Croatia
Sandra Radić Brkanac ; Department of Biology, Faculty of Science, University of Zagreb, Rooseveltov trg 6, HR-10000 Zagreb, Croatia

Abstract

Water deficit in the soil leads to osmotic stress in plants. The type of stress affects plant water relations, osmolyte accumulation and oxidative stress balance. The present study aimed to investigate the effects of osmotic stress on the Croatian perennial species Fibigia triquetra (DC.) Boiss, adapted to a hot and dry habitat. Plants grown in culture conditions were subjected to isoosmotic concentrations of mannitol and polyethylene glycol (PEG) and certain physiological and oxidative stress parameters were analyzed during a period of 14 days. Dry weight and proline content in Fibigia triquetra shoots increased in response to osmotic stress while the relative water content decreased. After an initial rise, chlorophyll and carotenoid levels in treated plants dropped to untreated plant levels. Oxidative damage to proteins and especially to lipids was evident upon PEG-induced osmotic stress. Superoxide dismutase and ascorbate peroxidase appear to play an essential protective role in stressed plants. Regardless of the osmotic agent, accumulation of heatshock proteins of 70 kDa was noticed under osmotic stress. The tolerance of the plant species to osmotic stress seems to be associated with increased capacity of the antioxidative
system and efficient photoprotective system.

Keywords

antioxidative enzymes; lipid peroxidation; mannitol; osmotic stress; oxidative damage; polyethylene glycol; proline; stress proteins

Hrčak ID:

127800

URI

https://hrcak.srce.hr/127800

Publication date:

2.10.2014.

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