Feeding response of the cotton aphid,Aphis gossypii, to sublethal rates of flonicamid and imidacloprid

Abstract

The cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is an important sap-sucking pest of many plants, including melons and peppers. This study was conducted to determine the effects of sublethal exposure to flonicamid and imidacloprid and the mechanisms by which these insecticides affect the feeding behavior of A. gossypii. The median lethal concentrations (LC 50 ) of flonicamid and imidacloprid for adult A. gossypii were 2.40 and 1.92 mg l À1 , respectively. The lower lethal concentrations of flonicamid were 1.01 mg l À1 (LC 30 ) and 0.29 mg l À1 (LC 10 ), and those of imidacloprid were 0.82 mg l À1 (LC 30 ) and 0.24 mg l À1 (LC 10 ). The developmental period of A. gossypii nymphs at LC 30 was 3.6 days for both insecticides, which was shorter than that of the untreated controls (4.2 days). Longevity and total fecundity of A. gossypii adults were decreased at the sublethal concentrations of both insecticides. The lowest net reproductive rate was observed in A. gossypii treated with the LC 30 of flonicamid. Feeding behavior analyses using an electrical penetration graph showed that sublethal concentrations of flonicamid and imidacloprid had significant effects on the duration of phloem ingestion. Higher doses of flonicamid induced starvation by inhibiting phloem ingestion, whereas imidacloprid acted as a contact toxin rather than an inhibitor of feeding behavior.

Sublethal and transgenerational effects of dinotefuran on biological parameters and behavioural traits of the mirid bug Apolygus lucorum

“…This finding was in accord with the previous reports on A. gossypii exposed to LC 20 of cycloxaprid 39 and B. tabaci treated by LC 25 of imidacloprid 40 . However, significant impacts on the demographic parameters were shown in A. lucorum treated with LD 15 of sulfoxaflor 41 ; in M. persicae exposed to imidacloprid 17,23 or thiamethoxam 20 ; and in A. gossypii 24 , Aphis glycines 42 and R. padi 43 exposed to imidacloprid. Zhen et al 41 showed that the LD 15 of sulfoxaflor significantly reduced the r, λ, T, R 0 , and gross reproduction rate (GRR) of the F1 generation of A. lucorum compared with the control.…”

“…They selectively act as agonists of insect nicotinic acetylcholine receptors (nAChRs), preventing signal transduction and in turn resulting in a lasting impairment of the nervous system and the death of insect 12,13 , and such insecticides have been used to control aphids, whiteflies and thrips in many agricultural crops 14 . In addition to kill the pests directly, these insecticides also exhibited sublethal effects on the physiological and behavioural traits of insect pests, such as survival 15,16 , development duration 17-19 , fecundity 16,18,20-22 , and feeding behaviour [23][24][25][26][27] Pan et al 18 observed reduction in adult longevity, oviposition period, fecundity, and egg hatching rate but an increase in the pre-oviposition period of A. lucorum at either LD 10 or LD 40 of cycloxaprid. Daniels et al 27 reported that a sublethal dose of thiamethoxam (0.8 mg L −1 ) reduced xylem feeding by Rhopalosiphum padi.…”

“…Daniels et al 27 reported that a sublethal dose of thiamethoxam (0.8 mg L −1 ) reduced xylem feeding by Rhopalosiphum padi. Thus, the sublethal effects caused by these insecticides should be rigorously assessed to determine the response characteristics of insect pests.Electrical penetration graphs (EPGs) are an effective tool to study the feeding behaviour of sap-sucking pests such as aphids [23][24][25]27 . However, phytophagous mirids produce no salivary sheath 28 and perform macerating or lacerating behaviour [28][29][30][31] .…”

“…Fortunately, the biological meaning of the feeding waveforms in a few species of mirid bugs was recently clarified in several studies 29,32,33 . Additionally, EPGs were also applied to reveal the impacts of neonicotinoid insecticides on the feeding behaviour in Aphis gossypii 24,34 , Myzus persicae 23,35 , Sitobion avenae 25 , and R. padi 27,36 . Cui et al 25 found that cycloxaprid significantly increased the total length of non-probing periods and inhibited the phloem ingestion of S. avenae.…”

Evaluación del riesgo ecológico de insecticidas utilizados contra plagas hortícolas en el agente de control biológico Nesidicoris tenuis Reuter (Heteroptera: Miridae)

“…Para las hembras de N. tenuis, deltametrina redujo el consumo respecto del testigo de forma significativa y la respuesta funcional mostró una tasa de ataque (a) muy inferior a la obtenida en el tratamiento de agua, lo que altera la habilidad del depredador como regulador de la población de la presa (Li et al 2006). Aphis gossypii Glover (Hemiptera: Aphididae) en condiciones de laboratorio sobre hojas de pimiento (Koo et al 2015).…”