Huang H.-Y.,Gansu Key Laboratory of Crop Genetic Improvement and Germplasm Enhancement |
Huang H.-Y.,Gansu Agricultural University |
Ma W.-F.,Gansu Agricultural University |
Chen X.-Y.,Lanzhou University |
And 2 more authors.
Chinese Traditional and Herbal Drugs | Year: 2011
Objective: To establish the system of high frequency chromosome doubling and to lay the fundation for obtaining the strain of licorice with a high active ingredient content. Methods: Exogenous hormone of naphthalencacetic acid (NAA) and 2, 4-dicholorophenoxyacetic acid (2, 4-D) were used to induce callus of Glycyrrhiza uralensis explants from cotyledons, hypocotyls, and radicle, and the effect of NAA and 2, 4-D were tested on callus cell ploidy and content of secondary metabolites. Results: The result showed that there were significant effects of NAA and 2, 4-D with different concentrations on cell ploidy of different explants callus. The frequency of cell with chromosome 2n > 14 and 2n = 28 was significantly higher in hypocotyls callus than those in cotyledons and radicle. They were up to 42.38% and 25.19%, respectively. Meanwhile, the frequency of cell with 2n >14 and 2n = 28 in cotyledons, hypocotyls, and radicle callus all reached the highest under the concentration of 2.0 mg/L NAA, 2.0 mg/L 2,4-D, and 1.0 mg/L 2,4-D, respectively. They were up to 61.50%, 39.20%, 63.00%, 36.23%, 63.50%, and 37.50%, respectively. The doubling rate of callus cell increased by the extension of cultured time. Furthermore, there were significant effects of NAA and 2,4-D on promoting the contents of glycyrrhizic acid and licorice flavanone. The contents of glycyrrhizic acid and licorice flavanone of cotyledons callus reached the highest on MS medium with 1.0 mg/L NAA and 1.0 mg/L 2,4-D, they were up to 52.13 mg/g and 8.36 mg/g, respectively.And the contents in hypocotyls callus reached the highest on MS medium with 2 mg/L NAA, they were up to 49.01 mg/g and 8.54 mg/g, respectively. Besides the contents of glycyrrhizic acid and licorice flavanone showed positive correlation with chromosome doubling frequency of callus cell. Conclusion: There are significant effects of NAA and 2, 4-D with different concentrations to promote chromosome doubling and the content increasing of glycyrrhizic acid and licorice flavanone in different explants callus. It suggests that perhaps the new material in licorice with higher pharmacodynamic components will be obtained by chromosome Doubling.