Acta Univ Latv (2008) 745: 179–186

Growth of tissue culture and changes in oxidative enzyme activity of Sorbus and tayberry cultivars during cold storage

Abstract

The aim of the present work was to compare the effect of different concentrations of sucrose on success of long-term cold storage of two woody plant tissue cultures – Sorbus and tayberry cultivars. Increased sucrose concentration significantly diminished the number of necrotic shoots for Sorbus explants. High sucrose concentration in the medium together with other optimal cultivation conditions allowed successful storage of Sorbus and tayberry cultivars without subculturing for five years. After transplanting to fresh medium at 24°C explants completely renewed growth and development. During the period of initial growth inhibition at low temperature the activity of oxidative enzymes peroxidase and polyphenol oxidase increased, reaching a peak value when growth of the explants resumed. Increase of both peroxidase and polyphenol oxidase activity during the period of growth inhibition was positively correlated with the concentration of sucrose in the incubation medium.