Effects of methyl jasmonate on the trichomes and secretions of Chrysanthemum indicum var. aromaticum in leaves

By spraying methyl jasmonate of different concentrations and different treatment time on Chrysanthemum indicum var. aromaticum, trichomes density and the components of secretions in leaves were measured. The results showed that the density of T-shaped non-glandular trichomes and capitate glandular trichomes in leaves of C. indicum var. aromaticum were increased first and then decreased when the concentration of methyl jasmonate and treatment time were increased, the tip changed significantly than the middle leaves and leaf bases. The relative content of terpenoids increased with the increasing concentration of methyl jasmonate and treatment time, bicyclo3.1.0hex-2-ene, 4-methylene-1- (1-methylethyl)- and caryophyllene changed obviously. The concentration of benzene and alcohols began to fall when their relative content reached highest. At the concentration of 0.5% (24 hours) or 48 hours (0.25%) treating time, the content of p-cymene and aromadendrene began to decline, α-panasinsen, maaliene, guaiene and cis-sabinol decreased to 0. This indicates that methyl jasmonate could induce trichomes and the components of secretions in leaves of C. indicum var. aromaticum, and the best induction effect was achieved when the concentration was 0.25% and the treating time was 24 hours.