Developmental aspects of long-term callus culture ofVicia faba L

Vicia faba callus line (VFS1), isolated from explants of immature embryo, grew satisfactoriliy on Murashige and Skoog complete medium with 1.38 µM 2, 4-D, or with 0.92 µM 2, 4-D to which 1.0 µM kinetin was added. It also grew well on the B5 modified medium containing 2.3 µM 2, 4-D and 25.0 µM kinetin. On the last of these media the cultures grew more uniformly and without necrosis. They also showed diminishing variation in poliploidy in favour of diploids and corresponding aneuploids (hypodiploids). After being cultured for nearly three years on MS containing 1.38 µM 2, 4-D, 8-33% of cultures of VFS1 were able to regenerate roots when transferred to either MS half strength with 5.37 µM NAA, or to a medium without 2, 4-D, or else to media with addition of kinetin only (in various concentrations).