Chemical polyploidization of Chrysanthemum boreale

Abstract

Chrysanthemum boreale (Asteraceae) is a wild flowering plant that has both ornamental and herbal uses. In the present study, colchicine was used as a chemical mutagen to induce polyploidy using in vitro shoots, which were cultured from C. boreale (2n = 2x = 18) nodal segments, and the efficacy of various colchicine concentrations and treatment durations were investigated. The results demonstrated that the induction of tetraploid plants by colchicine treatment were clearly successful. A total of 21 tetraploid and 110 chimera plants were identified using the chromosome counting method, and the colchicine concentrations of 200 ppm (48 h) and 300 ppm (12 and 24 h) were the most effective for inducing tetraploidy. Details about the successful induction, morphological characteristics, and cytology of the polyploids are described and compared with those of control plants. The tetraploid plants exhibited thicker and larger leaves, as well as larger and fewer stomata than the diploid plants. In this study, the polyploid plants of Chrysanthemum were induced successfully using colchicine treatment. This procedure contributed to the improvement of high-value species in the Chrysanthemum breeding program.