CALLUS GROWTH AND SOMATIC EMBRYOGENESIS IN THALAMUS TISSUE OF RANUNCULUS-ASIATICUS L CULTIVATED IN-VITRO - CYTOKININ EFFECT AND PHENOL METABOLISM

The effect of cytokinin on growth and plant regeneration of thalamus-d erived calluses of Ranunculus asiaticus L. has been investigated with various concentrations of 6-benzyladenine and 6-furfurylaminopurine (k inetin), in a medium containing 2,4-dichlorophenoxyacetic acid levels, which was decreased to 0 over three subcultures. Cytokinins, although not essential for initiating callus production, improved subsequent c allus growth and plant regeneration No somatic embryogenesis was obser ved on calluses grown on media lacking cytokinins or containing only k inetin. Calluses manifested embryogenesis on media containing 6-benzyl adenine plus kinetin or only 6-benzyladenine, Nondifferentiating callu s was characterized by a high content of phenolic polymers and an elev ated peroxidase and polyphenol oxidase activity in comparison with dif ferentiating callus. Differences in simple phenol concentrations were observed in the two kinds of callus.