Increasing the Expression of Genes Chavicol O-Methyl Teransferase and Cinnamate 4-Hydroxilase under Methyl Jasmonate Treatment in Medicinal Plant Basil (Ocimum basilicum L.)

Basil is a rich source of phenylpropanoids and enzymes Chavicol o-methyl transferase and cinnamate 4-hydroxylase are involved in the biosynthesis of these compounds.
Material and A completely randomized design with three replications was conducted in greenhouse to assess the effect of methyl jasmonate on the expression of the genes encoding CVOMT and C4H enzymes. Methyl jasmonate with concentrations of 0, 0.1 and 0.5 mM was sprayed on healthy plant leaves in flowering stage. Plant leaves were sampled at 0, 24, 48 and 72 hours after spraying. Relative expression of the genes was determined by real time PCR. Methyl jasmonate concentrations and sampling times were considered as main and sub-plots, respectively, and analysis of variance was performed in a split plot in time design.
Based on the results of variance analysis and mean comparison tests, the highest expression of the CVOMT gene was achieved in a concentration of 0.5 mM methyl jasmonate at 48 hours after spraying (p≤0.01). The expression of the C4H gene was significantly (p≤0.05) affected by the methyl jasmonate concentrations and sampling times. The maximum expression of this gene was obtained in 0.1 mM concentration of methyl jasmonate. Also, the expression of C4H gene was reached its peak 48 hours after spraying.
Methyl jasmonate with concentrations of 0.1 and 0.5 mM methyl jasmonate lead to significant increase in the expression of the genes encoding CVOMT and C4H enzymes which could probably increase the production of phenylpropanoids such as chavicol and methyl chavicol.