Fumigant toxicity of the essential oil derived from Carum copticum C.B. Clarke (Apiaceae) were assessed against growth stages of Indian meal moth, Plodia interpunctella (Hubner) (Lepidoptera: Pyralidae). Seeds of the plant were collected from Tehran, Iran and hydrodistilled to extract their essential oil. The essential oil was analyzed by GC and GC-MS. Thymol (64.51%), γ-terpinene (17.52%) and p-cymene (16.16%) were the main components among the eight constituents characterized in the oil, representing 98.19% of the total components detected.All bioassay tests were conducted at 25 ± 1°C, 65±5% RH and photoperiod of 16:8 h (light:dark). After These findings indicated that essential oil from seeds of C. copticum could have potential of practical value for application in management of the Indian meal moth in storage.

Plant secondary metabolites play an important role in plant-insect interactions and therefore such compounds may have insecticidal or antifeedant activity against insects. Carum copticum C. B. Clarke (Apiaceae) is one of these plants that have medicinal effects on humans. The chemical composition of the essential oil from dry seeds of C. copticum was studied by gas chromatography (GC) and gas chromatography mass spectrometry (GC-MS). Thymol (41.34%), α-terpinolene (17.46%) and ρ-cymene (11.76%) were found to be the major constituents of the oil. In fumigant toxicity tests with the essential oil against adults of Sitophilus oryzae (L.) and Tribolium castaneum (Herbst) at 27±1 o C and 60%±5% RH, it was observed that S. oryzae (LC 50 = 0.91 μL/L) were significantly susceptible than T. castaneum (LC 50 = 33.14 μL/L). The mortalities of the insect species reached 100% at concentrations higher than 185.2 μL/L and 12-h exposure time. The findings indicate the strong insecticidal activity of C. copticum oil and its potential role as a fumigant for storedproduct insects.Chemical constituents and fumigant toxicity of Carum copticum 215 † Units LC 50 and LC 95 = μL/L, applied for 24 h at 27 o C. ‡ 95% lower and upper fiducial limits are shown in parenthesis.

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Fumigant activity of essential oil vapors distilled from Carum copticum C. B. Clarke and Vitex pseudonegundo Hand I. MZT. was tested against eggs, larvae and adults of Callosobruchus maculatus (F.). Fumigant toxicity was assessed at 27 ± 1°C and 60 ± 5% RH, in dark condition. The influence of different concentrations of the essential oil vapors on egg hatchability, larval and adult mortality was significant. Data probit analysis showed that lethal concentration of the essential oil to kill 50% of the population (LC 50 ) for egg, larvae and adult were found to be 1.01, 2.50 and 0.90 ll/l air of C. copticum oil, followed by 2.20, 8.42 and 9.39 ll/l air essential oil of V. pseudonegundo, respectively. Between these essential oils, C. copticum was almost more toxic than V. pseudo-negundo on all growth stages of C. maculatus. The present study suggests that essential oils from these medicinal plants may be potential grain protectants as botanical alternative fumigants and could be used in the management of various life stages of C. maculatus.