Fig. 2.

Level of endogenous free IAA in the leaf from in vitro-grown plants of the interspecific hybrid Helianthus annuus × H. tuberosus. Free mean (± s.d.) IAA concentrations in three independent experiments each with three replicates. Columns marked with the same letter are not significantly different at the P = 0·05 level according to Tukey's test. Abbreviations: A-2, leaves of the non-epiphyllous clone; EMB-2 EP, epiphyllous leaves of the EMB-2 clone; EMB-2 NEP, non-epiphyllous leaves of the EMB-2 clone.