APICAL CALLUS FORMATION IN SOLIERIA-FILIFORMIS (GIGARTINALES, RHODOPHYTA) CULTURED IN TANKS

Loose-lying wild plants of the carragenophyte Solieria filiformis (Kut zing) Gabrielson were cultivated under greenhouse conditions in 600 1 tanks in stationary and turbulent cultures, produced either by air bub bling or water jets at the bottom of the tanks. One week after inocula tion 90.3% of the apices of the plants grown in air turbulent cultures initiated the formation of callus. The apices were not broken and app arently non-wounded. No callus formation were observed from a few acci dentaly broken apices in any culture. Only 4% of the apices in water t urbulent cultures induced callus. Reorganization of branches from the calli took place after three weeks. Organogenetic calli detached from the mother plant after four weeks and formed spherical masses of 3 cm in diameter growing as unattached balls. Cellular disorganization (i.e . callus formation) in S.filiformis seems to be a consequence of inter mittent abrasion or contact stimuli against tank walls produced by tur bulence.