Effects of novel and commercial phytochemicals on beneficial arthropods

Pesticides have been proven to be noxious to non-target organisms, including beneficial arthropods. Moreover, pesticide applications, kill a broad range of natural enemies and pollinators, resulting in pest outbreaks of pesticide resistant phytophagous species and a worldwide shrinking of the pollinators' populations. Natural pesticides called phytochemicals, are considered environmentally friendly alternatives to conventional pesticides, presenting lower risk to animals and humans. To minimize the environmental impact and the disruption of the species interactions, the potential lethal and sublethal effects of phytochemicals on beneficial arthropods must be evaluated.The aim of this study was to evaluate the toxicity of five phytochemical pesticides (Requiem (R), Eradicoat (R), Prev-Am (R), FLiPPER (R), BPA044I), on two predatory mites, two predatory insects and one pollinator, which are all important components of current integrated pest management (IPM) programs. The lethal and sublethal effects of the phytochemicals were evaluated on the phytoseiid mites (Acari, Phytoseiidae), Phytoseiulus persimilis (Evans), and Amblyseius swirskii (Athias-Henriot), as well as the predatory insects Nesidiocoris tenuis (Reuter) (Heteroptera: Miridae) and Orius laevigatus (Fieber) (Heteroptera: Anthocoridae). Also, the lethal effects were evaluated on the pollinator Bombus terrestris L. (Hymenoptera: Apidae) which is used in greenhouse pollination. We evaluated the acute toxicity of the phytochemicals on adult arthropods and the effects on the predator fecundity, when exposed directly and indirectly through residues.Requiem (R) and BPA044I were harmless or slightly harmful to the mite and insect predators (toxicity <49%), nor did they affect their fertility, according to the IOBC classification. Eradicoat<(R)> was harmless to N. tenuis, but it had moderate toxicity to mites and O. laevigatus (<50%). Prev-Am<(R)> had high toxicity (>50%) on mites and low on insects, while FLiPPER (R) was moderately to highly toxic to all predators. The tested phytochemical products exhibited very low toxicity on the pollinator B. terrestris, with either oral or topical exposure and very high repellency. Overall, the evaluation of natural pesticide effects on biocontrol agents and pollinators is crucial for implementing successful IPM strategies.

Automated summary

Pesticides have harmful effects on non-target organisms, including beneficial arthropods and pollinators. Natural pesticides are considered safer alternatives. Evaluating their toxicity and impact on beneficial arthropods and pollinators is crucial for successful pesticide use.