Susceptibility of Asian citrus psyllid, Diaphorina citri (Hemiptera: Liviidae), to the insecticide afidopyropen: a new and potent modulator of insect transient receptor potential channels

Xue Dong Chen,Muhammad Ashfaq,Lukasz L. Stelinski

doi:10.1007/s13355-018-0574-8

Abstract

A relatively new insecticide chemistry for controlling sucking insects, afidopyropen, was investigated for toxicity against Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae). We evaluated the mortality of D. citri eggs, nymphs, and adults treated with afidopyropen using both laboratory-reared and field populations. We also quantified the effects of sublethal doses of afidopyropen on D. citri feeding, host choice selection, and fecundity. For laboratory susceptible adults, the contact LC50, topical application LD50, and leaf dip LC50 were 2.13, 2.00, and 3.08 ng/µL, respectively. For adults collected from a commercially managed citrus grove in Florida, the contact LC50, topical application LD50, and leaf dip LC50 were 1.37, 1.92, and 4.89 ng/µL, respectively. Egg hatch was significantly reduced following exposure to afidopyropen at 100 ng/µL. Furthermore, afidopyropen reduced D. citri nymph survival and adult emergence at concentrations ranging between 0.01 and 100 ng/µL. Diaphorina citri adult feeding decreased on citrus leaves treated with afidopyropen in a concentration-dependent manner as measured indirectly by honeydew excretion, and appeared almost completely inhibited after treatment with 10 and 100 ng/µL solutions of afidopyropen. In choice tests, significantly fewer D. citri adults settled on afidopyropen-treated plants than on control plants at 24, 48, and 72 h after release, with no differences in settling between males and females. Afidopyropen reduced the fecundity of D. citri in a concentration-dependent manner. Collectively, the results suggest that afidopyropen could contribute to the integrated management of D. citri and may therefore be useful in rotational programs to improve resistance management.

Highlights

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is a serious pest across Asia, USA, and Brazil (FFTC 2009, 2012; Kiritani and Su 1999; Narouei-Khandan et al 2015; Rogers 2008; Shinohara et al 2006; Stansly and Rogers 2006; Tomimura et al 2014)
We present an investigation evaluating the general toxicity of afidopyropen against D. citri using both a laboratory population with known susceptibility to multiple insecticide classes as well as insects collected from a field population treated with insecticides according to grower norms in Florida
Our objective was to evaluate the response of laboratory and field populations of D. citri to a new insecticide, afidopyropen

Summary

Introduction

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is a serious pest across Asia, USA, and Brazil (FFTC 2009, 2012; Kiritani and Su 1999; Narouei-Khandan et al 2015; Rogers 2008; Shinohara et al 2006; Stansly and Rogers 2006; Tomimura et al 2014). Afidopyropen is a new potent and specific modulator of insect transient receptor potential vanilloid (TRPV) cation channels, exhibiting unique binding (Kandasamy et al 2017; Nilius and Owsianik 2011). It is derived from natural products (Jeschke 2017; Leichter et al 2013). The insecticidal activity of chordotonal organ TRPV channel modulators is likely related to species selectivity at the target level and the importance of chordotonal organs for insect survival Their mode of action involves stimulating heterologously expressed transient receptor potential channels that act by targeting nanchung (NAN) and inactive (INA) proteins (Kandasamy et al 2017). Afidopyropen is practically nontoxic to other species—including German cockroach Blatella germanica (Linnaeus) (Blattodea: Blattellidae), yellow fever mosquito Aedes aegypti (Linnaeus) (Diptera: Culicidae), Colorado potato beetle Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), red flour beetle Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), house fly Musca domestica (Linnaeus) (Diptera: Muscidae), and fireflies Photuris spp. (Coleoptera: Lampyridae)—despite the presence of NAN and IAV transcripts (Leichter et al 2013)

Objectives

Methods

Results

Discussion

Conclusion