COLCHICINE TREATMENT: A METHOD FOR GENETIC DIVERSITY INDUCTION OF DORITIS PULCHERRIMA LINDL. ORCHID OF THAILAND
Doritis pulcherrima Lindl. is one of the orchid species in Asia, including Thailand. Natural diploid and tetraploid Doritis pulcherrima, 17 clones, were used in this research. The diploid MVP 12 clone was selected to culture with aseptic technique for protocorm producing. Protocorms derived from this clone were used to induce tetraploid orchid plants. Polyploidization was induced via 2 month aged protocorms with various colchicine treatments. The suitable treatment was 100 mg/L of colchicine for 10 days. The survival rate of protocorms and plantlets were 39.2 and 67.0%, respectively. The 25% of induced plantlets were observed as tetraploid by somatic chromosome counting. The five tetraploid plantlets were selected. They were 4N1, 4N1, 4N2, 4N2 and 4N3. Most morphological characteristics of plantlets were significant, except stem diameter, leaf number, root diameter, lateral sepal length, and lip length. The genetic relationship among Doritis pulcherrima plants were performed with Amplified Fragment Length Polymorphism (AFLP) fingerprinting, DNA bands were observed as raw data. Phylogenetic tree was constructed using NTSYSpc 2.1 software. Results showed closely genetic diversity of this orchid species and all tetraploid induction plants were very close to the diploid mother plant, except for the 4N3 tetraploid induction plant. This interesting observation was due to mutation during polyploidization, so the colchicine treatment was a technique to make wider genetic diversity for this orchid species.
Rungruchkanont, K. and Apisitwanich, S. (2015). COLCHICINE TREATMENT: A METHOD FOR GENETIC DIVERSITY INDUCTION OF DORITIS PULCHERRIMA LINDL. ORCHID OF THAILAND. Acta Hortic. 1078, 175-180
orchid, Doritis pulcherrima, polyploidization, colchicine treatment, AFLP, genetic diversity