Preliminary Investigation on the Toxicity of Different Formulations on Some Groups of Beneficial Arthropods in Emilia-Romagna Orchards

Control of the most relevant phytophagous of apple and pear trees in Emilia-Romagna (Northern Italy) is achieved by insecticides but it is improved also by defence techniques allowing protection of useful insects. It is therefore relevant to understand in detail the effects of the most common insecticides employed in integrated defence of the two above mentioned cultures on the main auxiliary insects, both predators and parasitoids. With this aim we performed open field tests to evaluate the acute toxicity (48 hours after the treatment), according to the method suggested by IOBC Working Group “Integrated Protection in Orchards” to test three recently developed active ingredient: Spinosad, Indoxacarb and Methoxyfenozide. These three principles were compared to Azinphos methyl, presently one of the most widely employed insecticides with a broad action spectrum. Spinosad is a natural insecticide compound, whose active principle is a toxin produced by Saccharopolispora spinosa, Indoxacarb and Methoxyfenozide are synthetic molecules, respectively belonging to the family of oxadiazines and moult accelerators, while Azinphos methyl is an organophosphate compound. The results show that Azinphos methyl is characterized by a lower selectivity towards generic Coccinellidae, while mortality towards Antochoris nemoralis is rather limited for all active principles tested, on the contrary to what observed for parasitoid Hymenoptera.