Alteration in plant tissue morphology and physiology induced by plasma treatment

Abstract

The expansion of plasma medicine and its demand for precise and localized in vivo treatments of living cells and tissues resulted in the fast development of various plasma devices that operate at atmospheric pressure. In the present study, plant undifferentiated compact tissue (calli) of Balkan endemic small bearded iris (Iris reichenbachii Heuff.) was treated using a plasma needle device designed for biomedical applications and tested with numerous diagnostic procedures [1]. Significant morphological alterations of the iris calli were observed after direct plasma treatment. The indicated changes evaluated at the surface of the calli tissue after prolonged culture could be attributed to an enhanced cell division (mitotic activity) of the plant cells and differentiation of friable calli stimulated by low-temperature plasma. The current morphological changes were followed by the significant shift in calli physiology. The results showed that the plasma treatment enhanced the accumulation of specific arabinogalactan proteins in the epidermal cells and extracellular space of the iris calli. At the same time, the plant antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX), that represent the main lines of plant cell defence against oxidative stress, exhibited different pattern of expression depending on the plasma treatment. The present study outlines that the plasma technique could be applied as an alternative and valuable approach for promoting regeneration and multiplication in a plant meristematic tissue culture.