The experiment was carried out under field conditions. Five accessions were included in this study: Medicago sativa, Medicago media, Medicago falcata and interspecific hybrids Medicago falcata x Medicago sativa, Medicago falcata x Medicago media. The results showed that best source of germplasm of winterhardiness were Medicago media, Medicago falcata and hybrids Medicago falcata x Medicago sativa, Medicago falcata x Medicago media. The plants material derived from this study, possessed winterhardiness sufficient to use them in Polish climatically conditions.
The characterization of fructan structure, occurrence, pathways of synthesis and possible functions in the light of current views are presented. Fructans are polymers of fructose. They occur in numerous species of higher plants, i.e. in vegetative tissues of temperate grasses and cereals. Fructans play a role as reserve carbohydrates. The possible rotes of fructans in cryoprotection and in osmotic potential regulation are also discussed. Fructans are synthesized from sucrose. Two enzymes are involved in fructan biosynthesis: sucrose fructosyl transferase (SST) and fructan fructosyl transferase (FFT). A fructan exohydrolase (FEH) catalyzes the depolymerization and remobilization of stored fructans.