ACCUMULATION OF PHENOLIC-ACIDS IN FILTRATE-TREATED ALFALFA CELL-CULTURES DERIVED FROM GENOTYPES WITH DIFFERENT SUSCEPTIBILITY TO FUSARIUM-OXYSPORUM

Alfalfa (Medicago sativa L.) cell cultures derived from a genotype susceptible to Fusarium oxysporum accumulated the double amount of phenolic acids than the culture derived from a genotype exhibiting increased resistance to Fusarium oxysporum (54.26 and 24.76-mu-g g-1 fresh mass, respectively). Phenolic acids bound as glycosides represented major fractions in both cultures (75 % and 69 % of total phenolics in sensitive and resistant cells, respectively). Treatment with a culture filtrate caused the changes in content and fraction composition of phenolic acids of the two cell lines. The total level of phenolics increased by 20 % in the challenged susceptible culture. The relative amounts of the investigated fractions of phenolic acids changed due to a tenfold increase in free acid content, a distinct decrease in ester- and glycoside-bound phenolics and an almost unchanged level of cell wall-bound acids. In contrast, filtrate treatment resulted in a 50 % increase in phenolic contents in the resistant culture as compared with control. The increase was caused by a threefold rise in the level of free acids, a twofold increase in ester-bound phenolic acids and a more than twofold increase in cell wall-bound phenolics. Treatment with a fungal filtrate also resulted in changes of the proportion of benzoic and cinnamic acid derivatives in both sensitive and resistant cell cultures.