The in vitro aphicidal activity of four medicinal plant essential oils i.e. Moringa oleifera, Eruca sativa, Raphanus sativus and Allium sativum at concentrations of 1, 2 and 4 % on the mortality of rose aphid, Macrosiphum rosae and black bean aphid, Aphis fabae were evaluated after 12, 24, 48 and 72 hrs of exposure time. Results revealed that individual mortality percentages generally increased with increasing of oil concentrations tested at the four exposure times. Among treatments of the essential oils on M. rosae mortality, arugula oil significantly gave the highest value at all concentrations and exposure times that was reached to 97.5 %; followed by garlic oil with value of 80.6 %; whereas, treatment of moringa and radish oils gave the lowest values of rose aphid mortality those were amounted to be 63.3 and 69.2 %, respectively. A similar trend was observed in respect to A. fabae, since arugula oil was the best treatment, but radish oil ranked second, then garlic and moringa oils. On the other hand, garlic oil at concentration of 1 % gave the lowest mortality of black bean aphid individuals after 12 and 24 h of exposure. The study indicates the possible use of such essential oils against two aphid species.
Key words: Macrosiphum rosae; Aphis fabae; essential oils; insecticidal activity; in vitro
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