Abiotic elicitation of Trifolium pratense L. Suspension culture

Important substances of secondary metabolism include flavonoids and isoflavonoids. The Trifolium pratense L. (Fabacae) suspension culture is characterized by low production of these metabolites and therefore we tried to influence the production output with elicitation. From their origin point of view, the elicitors are divided into two groups - biotic and abiotic. The latter group includes, for instance, the salts of heavy metals. Our work was aimed at observing the effect of the copper sulphate abiotic elicitor on the production of the Trifolium pratense L. suspension culture (variety DO-8 and variety DO-9) that was cultivated in Gamborg media supplemented with 2 mg.l^-1 of 2,4-dichlorophenoxyacetic acid and 2 mg.l^-1 of 6-benzylaminopurine. The maximum increase in the flavonoid production took place, when compared with the test check, during the 168-hour application of the 100 μmol concentration.
The DO-8 variety isoflavonoids production was stimulated namely during the 48-hour application of the 1 μmol concentration; the best elicitation effect of the DO-9 variety was achieved with the 168-hour application of the 10 μmol concentration.

Keywords: Trifolium pratense L. suspension culture; flavonoids and isoflavonoids; abiotic elicitation; heavy metals