The anti-viral studies of plant extracts of Bunium persicum and Zataria multiflora on Nicotiana glutinosa and N. tabacum against tobacco mosaic virus (TMV; Tobamovirus, Virgaviridae) in Iran

To investigate the anti-TMV effects of Bunium persicum (BP) and Zataria multiflora (ZM), a set of experiments was conducted in a completely randomised design (n = 3) (p < 0.05). First, TMV particles were treated with different concentrations (0.5, 1.0, 2.5, and 5.0% (v/v)) of BP and ZM extracts. Nicotiana glutinosa and N. tabacum were mechanically inoculated with extract-treated TMV preparations at three intervals (24 h pre, simultaneous, and 24 h post-virus inoculation). Subsequently, local lesion number, inhibition rate, symptom index, and TMV accumulation were measured. Results showed that both extracts displayed significant anti-TMV effects. The highest inhibition percentages for BP and ZM extracts were 65.5% and 52.06%, respectively. 24 h pre-virus inoculation of both extracts at 5% was most efficient in reducing symptom index and ELISA extinction value. Therefore, ZM and BP can be considered as novel anti-TMV plants. Further studies are needed to find their mechanisms and evaluate their antiviral effects against other plant viruses.