Abstract
The acquisition of freeze tolerance in winter plants involves, among other cellular responses, activated catabolism of cell wall polysaccharides, thereby liberating oligosaccharides. One of these was identified as an oligosaccharin (physiologically active fragment) that most likely originates from hemicelluloses. Treatment of winter wheat seedlings with the oligosaccharin at 2°C increased their freeze tolerance by ∼30%. Results obtained to date suggest that the oligosaccharin acts as an endogenous and systemic signaling molecule during cold adaptation.
Acknowledgments
This work was partially supported by grants from the Russian Foundation for Fundamental Investigations (Nr. 00-04-48220) and from the National Scientific Committee of Tatarstan (Nr. 03-3.9-234). It was also supported in part by the United States Department of Energy-funded Center for Plant and Microbial Complex Carbohydrates (DE-FG05-93ER20097).
Notes
LT50, temperature at which the efflux of 50% of the total electrolyte in the tissue occurs, which is equivalent to a 50% lethality of the seedlings; OS, oligosaccharin