Effect of Concentration and Duration of Colchicine Treatment on Polyploidy Induction in Dendrobium scabrilingue L.

Abstract

Summary The induction of polyploidy in Dendrobium scabrilingue L. was conducted by using colchicine treatment while being cultured on semi-solid VACIN and WENT (1949). Protocorm like bodies (PLBs) of diploid D. scabrilingue L. were treated with 0.000, 0.025, 0.050, 0.075 and 0.100 % (wt/vol) of colchicine for 3, 7, 14 and 21 d, respectively. The most effective treatment was 0.075 % (wt/vol) colchicine for 14 d which resulted in about 36.8 % surviving PLBs and with 43.1 % of tetraploid orchids, as measured by flow cytometry. Tetraploid plantlets showed broadened, 2–3 times thicker, less pointy, dark green leaves and increased stem and root diameter as compared to diploid plants. The results show that the ongoing selection process will provide improved and easier to cultivate D. scabrilingue L. of higher commercial value for Thai orchid growers.