Selectivity of phytossanitary products used on citrus orchards to Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae)

Abstract: The effect of some phytosanitary products used on citrus orchards on Chrysoperla externa was evaluated. The maximum dosages of thiametoxan, imidacloprid, milbemectin, pyriproxyfen and spirodiclofen were sprayed on eggs of this chrysopid in a Potter tower, with toxicity evaluations on this and subsequent development phases. The experiment was conducted at 25±2oC, 70±10% RH and 14-hour photophase in a complete randomized design with six treatments and thirty replicates. Survivorship of contaminated eggs, larvae, pupae and adults originating from contaminated eggs was evaluated. Addditonally, number and viability of F1 generation eggs were evaluated. Imidacloprid and spirodiclofen were statistically different from control with egg viability of 76.7% for both products, with 96.7% for control. As for thiametoxan, milbemectin and pyriproxyfen, they did not influence egg survival rate, with 93.3%, 80.0% and 80.0%, respectively. Spirodiclofen received the slightly noxious (class 2) classification.