Enhanced emission of linalool from floral scent volatile bouquet in Jasminum auriculatum variants developed via gamma irradiation

Gamma irradiation is utilized in floriculture for generating variants with improved traits. In the present study, stem cuttings of Jasminum auriculatum Vahl. were irradiated with different levels of gamma rays viz. 0, 10, 20, 30, 40 and 50 Gray (Gy) to examine any alterations on the profile of floral volatile compounds (FVOCs). It was demonstrated that low dose (10 Gy) could enhance the contents of desired FVOCs as compared to non-irradiated plants, indicating a hormetic effect. The concentration of linalool (a monoterpene volatile) in the floral scent bouquet was found to be increased by two-fold in 10 Gy gamma-irradiated variants as compared with control. A concurrent decrease in benzyl acetate concentration was also noticed. Principal component analysis (PCA) of major FVOCs could cluster the plants developed from high and low irradiation doses. Expression analysis of acetyl-CoA-benzylalcohol acetyltransferase (JaBEAT), monoterpene synthase (JaMTS) and MYB transcription factor (JaMYB) genes correlated well with the concentrations of the corresponding FVOCs. Inter simple sequence repeat (ISSR) profiling of 10 Gy gamma-irradiated variants revealed the presence of significant DNA polymorphism (36.67%), as compared with control.