Cytological differences in leaf explants of chicory genotypes K59 and C15 cultured under SE-inducing conditions. Light microscopic images of stages in direct SE in leaf explants from the genotypes K59 (a, b, c) and C15 (d, e, f); semi-thin (3 μm) sections from leaf explants at day 4 (a, b, d, e) and day 8 (c, f) of culture under SE-inducing conditions stained with toluidine blue. At day 4, reactivating (*) and reactivated (**) cells can be observed in K59 (a), a well as some recently divided cells (b; DC), whereas in C15 only some reactivating cells are present (c, d). At day 8, numerous somatic embryos (SE) can be observed in K59 explants. ST = stomate; VB = vascular bundle. Bars: 30 μm.