The physiological stage of donor plants determined to a great extent the morphogenic potential of Lachersalia (Jacq.) hybrid leaves, but the optimal stage for various cultivars was different. Contact of the bud-forming adaxial epidermal cells with the medium did not significantly stimulate in vitro bud formation on Lachenalia leaf explants, but resulted in the formation of callus from the buds of certain hybrids. Wounding on either the adaxial or the abaxial side of leaves had a stimulating effect on certain hybrids, but others did not respond significantly. A reduction in the length of explants from 10 to 3.3 mm resulted in an increase in the total number of buds formed by a specific amount of explant tissue (width of explant = 15 mm).

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Virus-indexed Ornithogalum cv. Rojel plants were produced by eliminating Ornithogalum mosaic virus (OMV) through meristem-tip culture. The best plantlet regeneration was obtained from meristems derived from adventitious buds which developed on leaf explants taken from mother plants at the flowering stage. Acyclovir had no effect as an anti-viral compound on plantlet regeneration or virus elimination. Adenine arabinoside retarded plantlet development at concentrations of 10mg1-1 and higher, while 5.0 mg 1 -I suppressed the virus concentration beneath a detectable level in young plants. All the mature plants, however, tested positively for the presence of OMV.

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