Improvement of the tissue culture technique for Melaleuca alternifolia

Tea tree oil is extracted from the leaves and twigs of Melaleuca alternifolia (Maiden & Betche) Cheel, and it is widely used in medicines, food preservatives, cosmetics and health care products. Traditional propagation of M. alternifolia from seeds does not necessarily transfer the desired characteristics from their mother trees, the seedlings are not uniform, and the multiplication rate from cuttings is relatively low. For these reasons, it is necessary to develop tissue culture techniques for this species. This study showed that an efficient explant initiation medium for M. alternifolia was MS 1/2 + BA 0.6 mg L-1 + NAA 0.1 mg L-1 + sucrose 30 g L-1, which yielded a 75.9 % initiation rate. An efficient multiplication medium was MS + BA 0.3 mg L-1 + NAA 0.15 mg L-1 + sucrose 30 g L-1, which yielded a 4.3 multiplication rate and 3.2 cm shoot length. The rooting medium was MS 1/2 + IBA 0.1-0.25 mg L-1 + sucrose 15 g L-1, which yielded a 100 % rooting rate, 2.94-3.32 roots per individual and 1.36-1.44 cm root length. Local red-core soil was suitable as a transplant medium, and yielded 98 % survival. This study improved the tissue culture technique for mass-propagation of M. alternifolia, enabling the production of high quality plants for market.