Variability of hydrogen peroxide and carbohydrate content in mosses with different desiccation tolerance under conditions of dehydration and rehydration
I. Boiko, Î. Lobachevska
Institute of Ecology of the Carpathians, NAS of Ukraine
11, Stefanyk St., Lviv 79000, Ukraine
The adaptive responses of moss species with different resistance to water deficit Funaria hygrometrica Hedw. and Bryum argenteum Hedw. in terms of dehydration and rehydration were investigated. It was established that dank moss F. hygrometrica rapidly loses significant amounts of water during dehydration, compared with a tolerant to desiccation B. argenteum, which is able not only to hold water, but also to intensive restoration of tissues moisture capacity due to rehydration. The changes of adaptive responses depending on the length of dehydration/rehydration in moss with different resistance to drying were revealed. In F. hygrometrica a significant increase in the hydrogen peroxide content due to dehydration was observed, while in B. argenteum increased activity of carbohydrate osmoprotectors synthesis was recorded. As a result of rehydration concentration of carbohydrates and hydrogen peroxide in gametophores of mosses was decreased. It was established that bryophytes with different ecological strategies exhibit similar mechanisms of desiccation tolerance; particularly in B. argenteum stability is realized due to higher activity of adaptive response, primarily constitutive cellular protection.
Keywords: desiccation tolerance, dehydration, rehydration, hydrogen peroxide, carbohydrates, bryophytes, Funaria hygrometrica Hedw., Bryum argenteum Hedw.