Effects of exposure to imidacloprid direct and poisoned cotton aphids <i>Aphis gossypii</i> on ladybird <i>Hippodamia variegata</i> feeding behavior

Abstract

Imidacloprid is a pesticide used to control aphid infestations of cotton plants. However, poisoned aphids also serve as food for the ladybird natural predator Hippodamia variegata. We investigated whether imidacloprid-treated eggs, pupae, and adults of H. variegata and poisoned aphids altered ladybird predatory behavior. Laboratory bioassay results demonstrated that 0.72 g/L imidacloprid was lethal to ladybirds. Imidacloprid significantly reduced the hatching and emergence rates of H. variegata, and these effects were time and dose dependent. Predation was most adversely affected when the ladybirds directly consumed poisoned aphids and less so when directly exposed to the insecticide at sublethal concentrations. Imidacloprid use in cotton fields should be restricted to the initial stages of aphid infestation to avoid the period when adult ladybirds are present.

Life-table parameters, functional response, flight ability, and cross-generational effects of matrine demonstrate its safety to Hippodamia variegata (Coleoptera: Coccinellidae)

“…In agroecosystems, pesticide impacts on natural enemies can be from direct exposure to insecticides (contact toxicity) or from feeding on contaminated prey or flower resources (oral toxicity) (Wumuerhan et al 2020). Most evaluations of the effects of insecticides on natural enemies measure lethal effects from contact toxicity.…”

“…In this area, farmers tend to apply nonselective insecticides on a calendar basis to control aphids in cotton fields, which has increased insecticide resistance in cotton aphids from moderate to extremely high levels for organophosphates, pyrethroids, neonicotinoids, carbamate insecticides (Patima et al 2019, Li et al 2021, Ma et al 2021). This pattern of widespread use of nonselective insecticides has also damaged populations of Hippodamia variegata Goeze (Coleoptera: Coccinellidae), the dominant natural enemy population of cotton aphid in the region (Aguiar Santos et al 2017, Skouras et al 2019, Wumuerhan et al 2020). To help develop natural enemy friendly insecticides for IPM of cotton aphid, our team investigated the toxicity of matrine against A. gossypii and H. variegata to evaluate its effectiveness against cotton aphid and its safety to the pest's key natural enemy.…”

Effects on Life‐History Traits of Hypogastrura viatica (Collembola) Exposed to Imidacloprid Through Soil or Diet

“…We also observed fungal hyphae bloom on filters at high concentrations (Supporting Information, Figure S6), which would otherwise be removed by Collembola grazing (H. P. Leinaas and S. M. Kristiansen, personal observation). Reduced feeding activity could also be due to H. viatica actively avoiding food spiked with high concentrations to reduce exposure because imidacloprid disrupts feeding behavior in Coleoptera (Wumuerhan et al, 2020) and Hemiptera (Miranda et al, 2016). Such a behavioral effect is seen in other Collembola presented with metal‐contaminated food (Filser et al, 2000).…”

Identification of Active Species in Photodegradation of Aqueous Imidacloprid over g-C3N4/TiO2 Nanocomposites

“…Imidacloprid (IMI), which is the most widely used pesticide in the group of neonicotinoids, is a pesticide that is used in agriculture such as in crop protection against aphids, leafhoppers, psyllids beetles, etc. [1], and parasite management [2]. The use of neonicotinoids has been registered in approximately 120 countries worldwide [3], and IMI is one of the top ten global agrochemicals used as a pesticide worldwide [4].…”