In vitro Propagation of Caprifig and Female Fig Varieties (Ficus carica L.) from Shoot-tips

Fig trees are threatened by the attack of Fig Mosaic Disease (FMD) on leaves and fruits caused by viruses of several genera. Shoot-tip culture is a convenient method for viral sanitation. For this purpose, a reliable protocol for rapid in vitro propagation was developed with shoot-tips of three major Tunisian local fig (Ficus carica L.) varieties Zidi (ZDI), Soltani (SNI), Bither Abiadh (BA) and one rare and recalcitrant caprifig Assafri (ASF). For each in vitro step, four Murashige and Skoog (MS) media with different combinations of plant regulators were used. The best initiation of shoot-tips with sizes 0.5, 1 and 1.5 mm was obtained on medium M3 containing 0.2 mg L-1 Benzyle Amino Purine (BAP), 0.1 mg L-1 1-NaphthaleneAcetic Acid (NAA) and 0.1 mg L-1 Gibberellic acid (GA3). The variety (SNI) showed the highest shoot-tip initiation potentialities for the establishment step with 100% of explant development rate. The shoot multiplication and plantlet development were provided by medium M6 with 0.5 mg L-1 BAP and 0.1 mg L-1 NAA. The highest average of leaf number increase (92 leaves per plant) and proliferation rate (16.91 branches per plant) were reached on M6. The best rooting rate (83.34%) was favored by medium M11 with half-strength MS and 1 mg L-1 Indole-3-Butyric Acid (IBA). Ex vitro rooting of fig plantlets was successfully performed on moist peat with success rate of 90%. The acclimatized fig vitroplants showed high establishment rates (92.1%) and rapid growth on substrates S1 composed by peat without symptoms of virus diseases or morphological abnormalities.