Propagation of Casuarina equisetifolia through axillary buds of immature female inflorescences cultured in vitro.

The study of the actinorhizal symbiosis in Casuarina equisetifolia requires an homogenous plant material. Consequently, we devised a method of micropropagation based on the use of immature female inflorescences (IFI) as explants. IFI excised from an adult tree formed multiple buds after 4-week incubation on Murashige and Skoog medium with 0.05 μmol 1(-1) NAA and 11.1 μmol 1(-1) BAP. The axillary buds evolved into 5-6 cm long shoots 5 weeks after the transfer of IFI on a similar medium except for the addition of activated charcoal. Rooting of the shoots was obtained on a third medium, without BAP or charcoal, but with 1 μmol 1(-1) NAA. The plantlets were transferred into soil. Their growth was satisfactory and no plagiotropic tendency was observed.