In vitro inhibition activity of essential oils from some Lamiaceae species against phytopathogenic fungi

[Display omitted] •The antifungal activity was determined against phytopathogenic fungi.•Oils were more effective for H. maydis (76.1–88.2% mycelia growth inhibition).•The oils displayed significant effect on the spore germination.•Oils have potential as biofungicides for protection of crop and food materials. Natural products have been in focus as alternative, effective and safe materials against the phytopathogens. Investigations show Nepeta oils as effective in controlling the food crops decay. The inhibitory effects of essential oils derived from Nepeta leucophylla, Nepeta ciliaris, Nepeta clarkei and Calamintha umbrosa against five phytopthogenic fungi have been determined. In vitro antifungal activity varied with their constituents and target species. More active being the oils containing oxygenated terpenoids. Helminthosporium maydis was sensitive to the all oils, IC50 values have 43.6–109.3μgmL−1. The N. leucophylla oil possessing oxygenated iridoids was more effective against H. maydis (IC50 value of 43.6μgmL−1) while N. ciliaris was more active against Fusarium oxysporum (IC50 value of 219.2μgmL−1). The oils were effective against the spore germination of all the tested plant pathogens.