Effect of Babylon weeping willow (Salix babylonica L.) extracts on rooting of stem cuttings of olive (Olea europaea L.) 'Nabali'

Four experiments namely: soaking stem cuttings of 'Nabali' olive in willow water shoot extract (SE), leaf extract (LE), wood extract (WE), and bark extract (BE) plus dipping in 4000 ppm K-IBA solution were performed to test the effect of the extracts on rooting the cuttings. Irrespective of K-IBA dipping, the results showed that soaking the cuttings in BE for 48 h gave a significant increase in rooting percentage (46.9%) while soaking them in SE or LE or WE was ineffective. Soaking the cuttings in SE for 4 h or BE for 12 h significantly increased callusing percentages (61.3 and 55.6%,) while soaking them in LE or WE was ineffective. Soaking the cuttings in SE or LE or BE for 2, 24, 48 h, respectively, caused a significant increase in average number of roots per rooted cutting (3.9, 3.6, 4.4) while soaking them in WE was not. Irrespective of soaking the cuttings in the four willow extracts, dipping the cuttings in K-IBA 4000 ppm gave significantly higher rooting percentages (45.9, 44.3, 44.5, and 46.0%). Callusing percentage was significantly reduced in SE (40.5%) as compared to the control (55.5%) while in LE, WE, and BE was not. Average number of roots per rooted cutting was significantly increased in the four experiments.