Table 1.
Chemical composition of essential oil isolated by hydrodistillation from dill seed.
Fig 1.
Effects of the samples at contact phase on colony diameter (cm) growth of S. sclerotiorum.
(A) The oil, (B) mixture of carvone and limonene, (C) limonene, (D) carvone. Values are means (n = 3) ± standard deviations.
Fig 2.
Effects of the samples at vapor phase on colony diameter (cm) growth of S. sclerotiorum.
(A) The oil, (B) mixture of carvone and limonene, (C) limonene, (D) carvone. Values are means (n = 3) ± standard deviations.
Fig 3.
Effects of the samples at contact phase on sclerotial germination of S. sclerotiorum.
(A) The oil, (B) mixture of carvone and limonene, (C) limonene, (D) carvone. Significant differences (p < 0.05) between means are indicated by the letters above histogram bars. Values are means (n = 3) ± standard deviations.
Fig 4.
Effects of the samples at vapor phase on sclerotial germination of S. sclerotiorum.
(A) The oil, (B) mixture of carvone and limonene, (C) limonene, (D) carvone. Significant differences (p <0.05) between means are indicated by the letters above histogram bars. Values are means (n = 3) ± standard deviations.
Table 2.
Mean lesion size following direct inoculation of detached oilseed rape leaves with mycelial agar plugs 12 h before and after treatment with concentration range of dill seed essential oil.
Fig 5.
Efficacy of the oil against S. sclerotiorum in potted plants.
(A) Control; (B)–(E) Treated with the oil (1.25, 2.50, 5.00, and 10.00 μL/mL); (F) Treated with carbendazol (1.00 mg/mL).
Table 3.
In vivo antifungal activity of dill seed essential oil against plant pathogenic fungus of S. sclerotiorum on greenhouse-grown oilseed rape plants.
Fig 6.
Scanning electron microscopy illustrated effects of the oil on microstructure surface of S. sclerotiorum.
Control (A, B, E, and F). Effects of essential oil on hyphal morphology (C and D). Effects of essential oil on surfaces of sclerotia and rind globular cells inside the sclerotium (G and H).
Fig 7.
Some possible mechanisms of the oil against S. sclerotiorum.
(A) UV spectrophotometric sterol profiles of S. sclerotiorum treated with the oil in comparison with those of the untreated control. (B) Effect of the oil on activity of malate dehydrogenase. (C) Effect of the oil on activity of succinate dehydrogenase. (D) Inhibitory effect of the oil on glucose-dependent acidification of medium in S. sclerotiorum. Significant differences (p < 0.05) between means are indicated by the letters above histogram bars. Values are means (n = 3) ± standard deviations.