Forficula auricularia (Dermaptera) in orchards: Monitoring seasonal activity, the effect of pesticides, and the perception of European fruit growers on its role as a predator or pest

Abstract

BACKGROUND We investigated several aspects that could affect the role of the European earwig (Forficula auricularia) as a generalist predator in orchards: (i) seasonal activity in apple orchards, (ii) effectiveness of two cardboard trap types (roll vs tape) to enhance earwig densities, (iii) the effect of pesticides (chlorpyrifos‐methyl, spinosad, indoxacarb, spirotetramat, pirimicarb, sulphur, fluopyram tebuconazole) on earwig survival and behaviour, and (iv) the perception of European fruit growers of the earwigs’ role as a predator or pest. RESULTS The highest activity of earwigs in apple trees was observed in summer. Roll traps were a more effective capture method than tape traps. The roll traps also significantly increased earwig abundances in trees. Only the earwigs exposed to the insecticides indoxacarb, spinosad and chlorpyrifos‐methyl had significantly higher mortality and more erratic behaviour than earwigs from the control treatment. Earwigs from orchards with long‐term (>10 years) application of chlorpyrifos‐methyl had significantly lower mortality when exposed to this insecticide than earwigs from nonsprayed orchards. The fruit growers perceived earwigs as natural enemies of aphids and psyllids but also as pests. However, they regarded the damage caused by earwigs as economically unimportant without the necessity for management against them. CONCLUSION Fruit growers can increase earwig densities by installing rolled cardboard bands around trees. The highest seasonal activity of European earwigs coincides with applications of insecticides in orchards. This could disturb the earwigs' potential to suppress pest populations because several insecticides widely used in orchards have lethal and sublethal effects on earwigs even though they seem to develop some degree of pesticide resistance over time. © 2020 Society of Chemical Industry

Compatibility of powdered sulphur and natural enemies for the control of Drosophila suzukii (Diptera: Drosophilidae): Effects on Anthocoris nemoralis (Hemiptera: Anthocoridae) and Trichopria drosophilae (Hymenoptera: Diapriidae) activity

“…Contrary to what was expected, powdered sulphur did not interfere with the activity of A. nemoralis . Limited previous studies similarly found no effects of sulphur‐based compounds on predator activity and behaviour (Niedobova et al., 2021; Satoh et al., 2012). This should support the previous general assumption that inorganic compounds and other fungicides appear to be safer to beneficial arthropods than organic and neurotoxic insecticides (Pekár, 2012; Pérez‐Guerrero et al., 2014).…”

Organic orchard floor management in peach: effects on arthropods and associated fruit injury in the Intermountain West

“…Additionally, direct feeding on fruits can cause fruit disfiguration, rendering the product unmarketable. This has been observed with green peach aphids feeding on fruits before shuck split, as well as European earwigs ( Forficula Auricularia Linnaeus), which can chew into the skin of ripe peaches and generate spots that make fruits unmarketable (Jana et al 2021). Lygus bugs ( Lygus spp., order: Hemiptera) on the other hand are known to create “cat-facing” injury, a characteristic fruit malformation of deep depressions and creases.…”

Limited effects of glyphosate on the behaviour and immunity of males from six populations of the European earwig

“…The use of crop protection products (which includes pesticides, herbicides and other chemical substances) is one of the most important and recent causes of ecosystem dysfunction and biodiversity loss (Jana et al 2021). Over the past decade, a growing body of evidence has shown that the spraying of these chemical substances on and off crops can affect not only the target plants and animals but also a wide range of non-target organisms, including insects (Desneux et al 2007).…”