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Damage of crop plants in Greece by aphids results in serious economic losses for growers. In Greece, aphids are mainly controlled by chemical insecticides such as neonicotinoids and pyrethroids. In the present study, the response of Myzus persicae (Sulzer) and Aphis fabae Scopoli (Hemiptera: Aphididae) parthenogenetic lineages to imidacloprid and deltamethrin was examined. We evaluated toxicity of imidacloprid and deltamethrin on the fourth instar larvae of Coccinella septempunctata L. and Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae). Most of the A. fabae lineages showed low resistance factors (RRs) to both insecticides. However, 40% and 100% of M. persicae lineages showed moderate Resistance Ratios RRs values (> 10) for imidacloprid and deltamethrin, respectively. The Hazard quotient (HQ) values indicated that imidacloprid and deltamethrin may adversely affect C. septempunctata and H. variegata. We suggest that, the use of these insecticides should be carefully applied within Integrated Pest Management (IPM) programs. [ABSTRACT FROM AUTHOR]

The coccinellids Coccinella septempunctata L. and Hippodamia variegata (Goeze) are two native predators in Greece as well as very important biological control agents against aphids for many crops. The conservation of these predators in IPM approaches requires knowledge of the toxicity and the effects of insecticides on their biological characters. In the present study, the effects of five insecticides (kaolin, mineral oil, insecticidal soap, pymetrozine and imidacloprid) on the mortality, developmental time and consumption of fourth instar larvae of C. septempunctata and H. variegata were studied under laboratory conditions. Kaolin, insecticidal soap and pymetrozine were harmless to the last instar larvae of C. septempunctata and H. variegata whereas imidacloprid was moderate toxic. We concluded that kaolin, insecticidal soap and pymetrozine could be incorporated into IPM programs in combination with the two predator species studied. [ABSTRACT FROM AUTHOR]