In vitro propagation of Artocarpus altilis (Park.) Fosberg (breadfruit) from mature plant material

A micropropagation protocol for Artocarpus altilis (breadfruit, yellow cultivar) using shoot tip explants taken from mature trees is outlined. Cultures were initiated from shoot tip explants (1-2 mm in length) on either N5K or N15K; (Margara, 1978) macronutrient formulation, MS (Murashige and Skoog, 1962) micronutrients and vitamins and 6-benzyladenine (BA, 4.4 mu M),. Single-node explants obtained from shouts formed at the initiation stage were used at tilt multiplication stage. Multiplication elongation and maintenance were possible on K30NH(4) (Margara. 1978) macronutrients;, MS micronutrients and vitamins and zeatin 2.2 mu M. Shoot elongation was not enhanced by the inclusion of gibberellic acid at 1.4 mu M 2.8 mu M or 14.0 mu M, along with zeatin at 2.2 mu M, when compared with those shoots cultured on zeatin only. N30NH(4) was found to be superior (with respect to shoot quality) to MS macronutrient formulations at the multiplication and maintenance stages, because the shoots with development were more vigorous than those formed on the other macronutrient formulations mentioned. Zeatin at 2.2 mu M yielded 50% more in vitro-formed shoots when compared with BA at 4.4 mu M for the same time period. Shoots rooted on hormone-free medium with a success rate of 60%. Regenerated plantlets were hardened with about a 40% success rate.