Rooting of aerial offshoots of date palm (Phoenix dactylifera L.) “Braim” by air layering method

Along with rooted ground offshoots, the date palm during the juvenile phase produces aerial offshoots, which are rootless and die after culturing. This study examined the stimulating effect of indole butyric acid (IBA) and its mixture with pyrogallol and fungicide captan on the rooting of date palm aerial offshoots. The combination of 2000 mg l-1 IBA + 0.5% pyrogallol + 0.3% captan was the most effective in the yield of rooted aerial offshoots in the date palm, which amounted to 100% after 14 weeks. This combination also showed the highest average number of small and large diameter roots and average root length per aerial offshoot (274, 152 and 23.75 cm, respectively). The addition of IBA with pyrogallol and captan was most effective on the aerial offshoot contents of starch, total carbohydrates and IAA, where the best results (35.7, 58.0, and 18.588 mg g-1 DW.), respectively, were obtained using 2000 mg l-1 IBA with 0.5% pyrogallol and captan 0.3%. The results also showed that the highest leaf chlorophyll content (6.56 mg g-1 FW.) was obtained in response to the above combination. The anatomical study showed that some vascular parenchyma cells had prominent nuclei and dense cytoplasm. Some of the meristemoids began to become individualized, the plane of cell divisions giving rise to the typical pointed shape of the root primordium. Therefore, by following these treatments, the aerial offshoots became ready for transplanting instead of being discarded.