The use of herbal extracts can be considered as an alternative method to minimize the effects of synthetic chemical pesticide used to control plant pathogens on human and environmental health. The essential oils (EOs) obtained from Thymus pectinatus (TP), Thymus convolutus (TC), and Thymus vulgaris (TV) by hydrodistillation were analyzed by GC/MS. The main components of TP, TC, and TV were thymol (52.2%), p-cymene (17.03%), eucalyptol (24.47%), camphor (16.84%), α-pinene (12.88%), and carvacrol (72.47%). The antifungal activity of EOs against plant pathogens including Fusarium oxysporum f. sp radicis-Iycopersici (FORL), Phytophthora infestans, and Rhizoctonia solani was evaluated by using the agar dilution method. The EOs of TV and TP inhibited mycelium growth 100 % in FORL P. infestans, and R. solani at 4 μL/petri dose. The EOs of TC did not affect mycelial growth of R. solani and R. infestans while the mycelial growth of FORL was inhibited by 36.11%. Our findings suggested the use of these essential oils can prevent fungal infections on plants as alternatives to synthetic ones.

This study aimed to determine the composition andthe antifungal activity of the essential oils of Vaccinium myrtillus and Laurus nobilis plants. In the study, 22 components were identified in the essential oil of V. myrtillus, which represented 100% of the total essential oils. Accordingly, 1,8-cineole (41.07%), β-Linalool (12.72%), α-Pinene (12.17%) and Myrtenol (6.48%) were determined as the main components of the essential oil of V. myrtillus. The essential oil of L. nobilis consisted of 39 compounds and 1,8-cineole (50.68%), α-Terpinyl acetate (14.19%), 4-Terpinenol (4.07%) and α-Terpineol (2.90%) were determined as the main components, which represented 100% of the total essential oils. In the trials, doses of 0 (control) 1, 2, 4, 8 and 10 μL/petri dish were used. V. myrtillus essential oil inhibited mycelial growth in Sclerotinia sclerotiorum (Lib.), Alternaria solani, Fusarium oxysporum f. sp. radicis-lycopersici (Sacc.) W.C. Synder & H.N. Hans (FORL) and and Verticillium dahliae Kleb by 61.38%, 100%, 80.36% and 57.91% respectively. Bay laurel essential oil at 10 μL/petri dish dose inhibited the mycelial growth of A. solani, S. sclerotiorum, (FORL) by 100%, whereas it inhibited the mycelial growth in V. dahliae by 61.23%. Study results showed that V. myrtillus and L. nobilis essential oils have strong antifungal activities.

The purpose of this study was to assess the effectiveness of essential plant oils from Vitex agnus-castus L. (VAC) and Myrtus communis L. against the plant pathogens, Fusarium oxysporum f. sp. radicis-lycopersici (Sacc.) W.C. Synder & H.N. Hans, Rhizoctonia solani J.G. Kühn., Sclerotinia sclerotiorum (Lib.) de Bary and Verticillium dahliae Kleb., and to determine the chemical composition of the compounds in these essential oils. GC/MS analysis was identified 25 different compounds in VAC essential oil, while the main compounds were determined as Eucalyptol (17.75%), β-Caryophyllene (13.21%) and Spathulenol (10.41%). On the other hand, the essential oil of M. communis, consisted of 16 different compounds which were Eucalyptol (49.15%), Myrtenol (19.49%) and α-Pinene (8.38%) being its main compounds. An assessment of antifungal activity was performed under in vitro conditions. Plant pathogens were inoculated onto Petri dishes (60 mm) containing PDA medium (10 mL/Petri-1), and plant essential oils were applied at concentrations of 0.5, 1, 1.5, 2, 5 and 10 (μL/Petri-1) into the 5 mm diameter wells opened on the Petri dish surface. After that, the Petri dishes incubated at 22±2 °C. The results of this study, the essential oil of M. communis, at a dose of 10 μL/ Petri, inhibited the 100% mycelium growth of V. dahliae, S. sclerotiorum and R. solani. The highest dose of VAC essential oil was also 100% inhibited V. dahliae and S. sclerotiorum. The LC50 and LC90 values of M. communis and VAC essential oil calculated for V. dahliae, FORL, S. sclerotiorum and R. solani. This plant extracts were shown by in vitro conditions to be potential antifungal agents.

In this study, we investigated the antifungal activity of four different chitosan against Sclerotinia sclerotiorum and Fusarium oxysporum f.sp. cucumerinum (FOC). In addition, molecular docking studies of the chitosan compound against plant pathogens have been evaluated. Concentrations of 0.2, 0.3, 0.5, 1 and 2 mg/mL of each chitosan were used. The activity rate increased as the amount of concentration increased. Strong antifungal effects were observed at concentrations of 1 and 2 mg/mL of chitosan used against test fungi. For the first time with this study, the activity of chitosan against F. oxysporum f. sp. cucumerinum and molecular docking studies against both test pathogens were determined.