The application of leafy explant micropropagation protocol in enhancing the multiplication ef®ciency of Alstroemeria

Six tetraploid Alstroemeria clones were micropropagated by rhizome multiplication, a system whereby the shoots were cut off from the rhizome and discarded. In a three-week subculture interval, the average rhizome multiplication rate for all genotypes was 2.3. In one selected genotype the discarded shoots were used to initiate another micropropagation system: the leafy explant micropropagation system. In this system the leaves with axils and stem tissue were cut off the discarded shoots and cultured for 10 days in shoot induction medium followed by subculture on shooting medium for the formation of adventitious shoots. From the discarded shoots of one rhizome explant, on an average 1.1 leafy explants could be excised. Thus, combining the rhizome micropropagation together with the leafy explant micropropagation, the total number of explants were enhanced twice. Regenerated plants from both micropropagation systems were grown in the greenhouse to maturity. Plants regenerated from leafy explants were morphologically identical to those originated from the rhizome micropropagation. The leafy explant micropropagation protocol was not only suitable for in vitro grown explants of different genotypes, but also applicable to in vivo grown explants. # 2000 Elsevier Science B.V. All rights reserved.