Improvement of 6-gingerol production in ginger rhizomes (Zingiber officinale Roscoe) plants by mutation breeding using gamma irradiation

Abstract Ginger (Zingiber officinale Roscoe) is a valuable culinary and medicinal plant. The compound 6-gingerol is the main gingerol in ginger rhizomes and it possesses interesting pharmacological and physiological properties. Mutation breeding involved using low doses of gamma radiation (5–30 Gy) to increase the genetic variability in ginger rhizomes (M1 generation). Ginger plants selected from the next generation (M2) were characterized and subjected to quantitative analysis for 6-gingerol content using HPLC of ginger extracts. M2 offspring from a parent ginger rhizome irradiated with 20 Gy was found to have a high 6-gingerol content (38.4 ± 0.01 mg/g methanol extract in comparison to 22.1 ± 0.03 mg/g methanol extract in non-irradiated control samples). Radiation induced genetic variability was also probed and confirmed using RAPD-PCR analysis. This research demonstrates the potential for ginger improvement and to our knowledge is the first to report the use of gamma radiation in breeding ginger plants with enhanced 6-gingerol content.