Plant regeneration from cell suspensions of spinach

Friable calluses induced from root segments of spinach (Spinacia oleracea L.,.) with a high amount of growth regulators (indole-3-acetic acid 48.52 mu M and gibberellic acid 10 mu M) were suspended in liquid medium. The cell fraction sized between 100 and 200 mu m was used to establish suspension cultures. Adventitious shoots and roots were obtained from the suspensions (3.2 x 10(5) cells per mi) by procedures comprising successive subcultures on two or three different media. In both of these procedures, the composition of the second culture medium (concentrations of plant growth regulators) had a key influence on the organogenesis of the suspensions. Regenerated shoots elongated and rooted on different solid media. Plantlets transplanted in soil grew and developed normally until flowering and produced seeds.