FRUCTANS IN CALLUS OF GOMPHRENA-MACROCEPHALA ST-HIL

The production of fructose-containing carbohydrates by leaf and node c allus of Gomphrena macrocephala St.-Hil. grown in three different auxi n to cytokinin ratios is described. The amount of these carbohydrates in node callus rose with increasing a-naphthalene acetic acid to 6-ben zylaminopurine ratios, while in leaf callus it tended to decrease. An homologous series of fructans was detected only in callus grown in 1:2 auxin to cytokinin ratio. These fructans were of the inulin series in contrast to the phlein series present in the tuberous root of intact plants. Fructose polymers were also detected in culture medium and the se made up approximately 98% of the total fructo-polysaccharides produ ced. The mean molecular weight of these polymers (40 kDa) was 3 times greater than that of fructan from intact plants. The fructo-polysaccha ride pool could be a reflection of different physiological processes t aking place in the callus rather than a direct effect of growth regula tor treatment.