Impact of activated charcoal, culture medium strength and thidiazuron on non-symbiotic in vitro seed germination of Pecteilis radiata (Thunb.) Raf

We investigated the effects of activated charcoal (AC), culture medium strength and various levels of thidiazuron (TDZ) on asymbiotic in vitro seed germination and seedlings development of Pecteilis radiata, an endangered terrestrial orchid. Seeds were inoculated in culture bottle containing quarter-, half- and full-strength Murashige and Skoog (1962) medium (MS) with 0, 1, 2, 4 or 8 μM thidiazuron (TDZ), 3% (w/v) sucrose, and 0.8% (w/v) plant agar. The culture medium strength, TDZ levels, and their interactions had a significant (P