Efficacy of the Laurus nobilis oils (Lauraceae) on Controlling of Aphis fabae (Hemiptera: Aphididae)

Abstract

In this study efficacy of essential and fixed oil of Laurus nobilis L., on controlling Aphis fabae Scopoli that grows on Vicia faba L. (Fabaceae) has been studied by experiments set up in the laboratories of Cukurova University Biology and Plant Protection Departments in 2016-2017. Fixed oils had previously been found to be effective on aphids according to death rate and Abbott test values, but they had also phytotoxic effects on plants. Therefore, the essential oils were preferred in the present study. In essential oil solution applications (prepared with hexane and glycerol monostearate), 100 mu L mL(-1) and overdoses caused significant phytotoxicity and according to the results hexane significantly caused the death of aphids, therefore, the study was continued without the use of hexane. The effects of hexane-free solutions prepared with glycerol monostearate were found statistically differences (p<0,05) between doses (5, 10, 25, 50 mu l mL(-1)). Especially the death rate and Abbott test results were higher at 25 and 50 mu L mL(-1) doses; however, no statistically significant difference was found 25 and 50 mu L mL(-1) doses. In addition, it was noticed that glycerol monostearate caused the death of aphids in the control group. Therefore, Tween 80 was used instead of glycerol monostearate in the last applications. In applications that prepared by Tween80, 25 and 50 mu L mL(-1) doses were found statistically significant (p<0,05) when compared to other doses (5 and 10 mu l mL(-1))but 50 mu L mL(-1) dose had phytotoxic effects. According to the results of this study, it is concluded that 25 mu L mL(-1) essential oil dose prepared by Tween 80 is the most suitable dose on aphid control.