Production of tetraploid Gentiana triflora var. japonica ‘Royal Blue’ plants

Abstract

The aim of this work was to test a protocol for producing tetraploid plants of Gentiana. Tetraploid plants were produced by growing in vitro cultures of Gentiana triflora var. japonica ‘Royal Blue’ in the presence of oryzalin for 4 weeks. A population of plants was regenerated from these in vitro cultures and transferred to the greenhouse. The treated plants were screened for higher ploidy level on the basis of leaf thickness and further confirmation of polyploidy was provided by measuring guard cell lengths. The tetraploid nature of one plant with larger than normal guard cells was confirmed by flow cytometry and chromosome counts. The mean nuclear DNA contents of 2C and 4C nuclei were 9.26 pg and 17.77 pg DNA, respectively. Mitotic chromosome counts from diploid and tetraploid plants were 2n=26 and 2n=52 respectively. © 2003 Taylor & Francis Group, LLC.