The effect of Persian lilac and fig plant crude aquatic and ethanolic extracts on disease caused by Cucumber mosaic virus in cucumber (Cucumis sativus) plants under greenhouse condition

Persian lilac (Melia azedarach) of Meliaceae family and fig (Ficus carica) of Moraceae family are considered to be as important medicinal plants native to Iran. In this study, the antiviral effect of the crude ethanolic and aquatic extracts of the persian lilac and fig plants in decreasing disease severity caused by Cucumber mosaic virus (CMV) in cucumber plants was assessed using with the double antibody sandwich ELISA (DAS-ELISA) and Semi quantitative-RT-PCR (Sq-RT-PCR). In addition, the transcription level of pathogenesis related protein-1 (PR-1), resistance and specific activity of phenylalanine ammonia- lyase (PAL) enzyme were evaluated using Sq-RT-PCR assay. ELISA results showed that the presence level of CMV in cucumber seedlings was significantly decrease up to 15 days after their treating with the 100 ppm of ethanolic and 1000 ppm of aquatic extracts of fig and persian lilac plants in compare to the non-treated control plants. The PR-1 expression level and PAL enzyme specific activity were also significantly increased compared to the non-treated control infected plants in samples treated with the ethanolic extracts of persian lilac and fig plants at the concentration of 100 ppm up to 15 days after treatments. Disease severity was also significantly decreased in cucumber seedlings treated with the 100 ppm concentration of ethanolic extract of the persian lilac and fig plants. Totally, results of this study indicated that the systemic acquired resistance might be activated against CMV by applying ethanolic extracts of persian lilac and fig plant used in this study in treated cucumber seedlings through different molecular and biochemical mechanisms.