Abstract

One-leaf shoots from protocorms of Phalaenopsis ‘Silky Moon’ were used as explants for protocorm-like bodies (PLBs) and plantlets induction. Culture media contained Hyponex (6.5N-6P-19K) in the presence or absence of Saturn fert (20N-20P-20K) supplemented with 22.2 μM N⁶-Benzyladenine (BA), 100 g l^-1 potato juice, 2.0 g l^-1 peptone, 30 g l^-1 sucrose, 1.0 g l^-1 activated charcoal and 2.0 g l^-1Phytagel. A local commercial fertiliser, Viking Ship (10N-20P-30K), with or without Saturn fert was used to compare the effects of organic supplements and fertilisers on growth and development of explants. All explants were cultured for 10 weeks. The medium containing 0.75 g l^-1 Viking Ship with 1.0 g l^-1 Saturn fert provided significant higher number of PLBs per explant (24.4) with new plantlets per explant (8.3) than values (17.0 PLBs and 2.4 new plantlets per explant) obtained from the medium containing 1.0 g l^-1 Hyponex with 1.0 g l^-1 Saturn fert. An organic supplement, either yeast extract or biotin or folic acid, in the Viking Ship medium [1g l^-1 (10N-20P-30K) Viking Ship without Saturn fert) and Hyponex medium [1 g l^–1(6.5N-6P-19K) Hyponex with (20N-20P-20K) Saturn fert] enhanced numbers of PLBs and/or numbers of plantlets. The most significant organic supplement was 0.05 mg l^–1 biotin in the medium containing 2.75 g l^–1 Viking Ship. Effects of organic supplements in appropriate culture medium components on PLBs and plantlets formation were discussed.

Key words: Phalaenopsis, protocorm, protocorm-like bodies, hyponex medium, viking ship medium, yeast extract, biotin, folic acid.