Relationship of the Growth of Orchid Tissue to Changes in pH of the Growth Medium

Abstract

Meristems and lateral buds of 10 orchid species were aseptically cultured in modified liquid Vacin and Went (VW) media supplemented with 20% coconut water (CW). Changes in the pH of the medium during incubation depended on the species of orchia and incubation time.
The formation of protocormilike bodies was also highly correlated with pH changes.
Meristems and lateral buds of Vanda T.M.A. were aseptically cultured in modified liquid VW media supplemented with 20% CW. To stabilise the medium pH at 4.8 or 5.6 (buffer) citric acid was added at a rate of 1.5 g/l. On hundred percent formation of protocormlike bodies occurred when tissue was cultured in a medium of low pH whithout buffering; a lower level of formation resulted in a medium containing citric acid as a buffer.