Methyl Jasmonate Elicited Helichrysum stoechas (L.) Moench Cell Suspensions, A Promising Source of Extracts with Allelopathic Activity?

International audienceHelichrysum stoechas (L.) Moench cell suspensions were analyzed by LC-ESI-QTOF, which highlighted the predominance of 3,5-O-dicaffeoylquinic acid (3,5-diCQA). Elicitation of H. stoechas cells with methyl jasmonate (200 mM) led to a massive rise in 3,5-diCQA, up to 5-fold-increase compared with control, reaching the concentration of 10.2 mg. g-1dry weight after 14 days of culture. Previous data showed that diCQA isomers are potent allelopathic compounds, thus the methanolic extracts of control and MeJa-elicited H. stoechas cells were tested for their phytotoxicity. With this in mind, activity on the seed germination and seedling growth of the model plant Lepidium sativum were tested. Phytotoxicity of both extracts occurred in a dose-dependent manner, with a greater activity of elicited cells extract. Indeed, in the concentration range from 0.31 to 0.83 mg. mL-1, the latter showed a significantly higher inhibition rate of L. sativum seedlings root growth, when compared to control cells extract. The data presented may contribute to explore new strategies towards the conception of bioherbicides from plant origin. To our knowledge, this study is the first report of the use of elicited plant cells grown in vitro as a raw material for the production of allelopathic metabolites