Document Type : Original Article
Authors
Department of Plant Protection, Faculty of Agriculture, Shahed University, Tehran, Iran
Abstract
The cabbage aphid was developed quicker and stronger resistance to increased application of insecticide than any other pest. In this research, according to the desired effect and harmless essential oils insecticidal activity of sublethal doses, LC10 and LC20 of plant essential oil of Ferula gommosa was studied on fertility life parameters and nymph production deterrence of B. brassicae aphid. The research was conducted in 25±1ºC, 60±5% RH and 16:8 (L:D) photoperiods in germinator. To study sublethal effects of essential oils, 15 fertilized aphids with same age were treated with sublethal concentrations and then fertility life table parameters were calculated and compared with control treatment. The results of bioassay experiments showed that two plant essential oils affected the cabbage aphid. Value of LC10, LC20 and LC50 for F. gommosa were 0.98, 1.86 and 6.31 μl/L air, respectively. The effect of sublethal doses of essential oil on the fertility life table parameters was significantly different from control. The highest effect on the reproductive and birth rates was recorded for LC20 and LC10 of F. gommosa, respectivily. Also treatment of LC20 and LC10 of F. gommosa was decreased the mean generation time and increased the doubling time, respectively. Regarding the nymph production deterrent, there was not significant difference between tested essential oils. The overall results showed that the Galbanum, Ferula gummosa essential oil has a high potential in controlling the cabbage aphid, B. brassicae especially in sublethal concentrations.
Keywords
)