Figure 1.

Effects of pretreatment of leaves of the embryogenic hybrid of Cichorium, with 0.5 mM polyamines (putrescine, spermidine, or spermine), of 330 mM glycerol,or of several concentrations of (± ) cis, trans abscisic acid (ABA), on the number of somatic embryos (mean ± SEM for n = 9 independent experiments). Conditions in abscissa (1 to 10) correspond to the pretreatment described just below in the column from the associated table. * indicates the values that are significantly different from that obtained without pretreatment (p < 0.05; Student-Fischer law).