Effect of insecticidal fusion proteins containing spider toxins targeting sodium and calcium ion channels on pyrethroid‐resistant strains of peach‐potato aphid (Myzus persicae). Issue 7 (28th August 2014)

• Record Type: Journal Article
• Authors: Yang, Sheng; Fitches, Elaine; Pyati, Prashant; Gatehouse, John A
• Is Part Of: Pest management science. Volume 71:Issue 7(2015:Jul.)
• Page Start: 951
• Page End: 956
• Publication Date: 2014-08-28
• Subjects: Pests -- Control -- Periodicals; Pesticides -- Periodicals; 632.9
• DOI: 10.1002/ps.3872
• Languages: English
• ISSNs: 1526-498X

Abstract

<abstract abstract-type="main" id="ps3872-abs-0001"> <title>Abstract</title> <sec id="ps3872-sec-0001" sec-type="section"> <title>BACKGROUND</title> <p id="ps3872-para-0001">The recombinant fusion proteins Pl1a/GNA and Hv1a/GNA contain the spider venom peptides <italic>δ</italic>‐amaurobitoxin‐PI1a or <italic>ω</italic>‐hexatoxin‐Hv1a respectively, linked to snowdrop lectin (GNA). Pl1a targets receptor site 4 of insect voltage‐gated sodium channels (NaCh), while Hv1a targets voltage‐gated calcium channels. Insecticide‐resistant strains of peach‐potato aphid (<italic>Myzus persicae</italic>) contain mutations in NaCh. The pyrethroid‐resistant <italic>kdr</italic> (794J) and <italic>super‐kdr</italic> (UKO) strains contain mutations at residues L1014 and M918 in the channel <italic>α</italic>‐subunit respectively, while the <italic>kdr</italic> + <italic>super‐kdr</italic> strain (4824J), insensitive to pyrethroids, contains mutations at both L1014 and M918.</p> </sec> <sec id="ps3872-sec-0002" sec-type="section"> <title>RESULTS</title> <p id="ps3872-para-0002">Pl1a/GNA and Hv1a/GNA fusion proteins have estimated LC<sub>50</sub> values of 0.35 and 0.19 mg mL<sup>−1</sup> when fed to wild‐type <italic>M. persicae</italic>. For insecticide‐resistant aphids, LC<sub>50</sub> for the Pl1a/GNA fusion protein increased by 2–6‐fold, correlating with pyrethroid resistance (wild type < <italic>kdr</italic> < <italic>super‐kdr</italic> < <italic>kdr</italic> + <italic>super‐kdr</italic> strains). In contrast, LC<sub>50</sub> for the Hv1a/GNA fusion protein showed limited correlation with pyrethroid resistance.</p> </sec> <sec id="ps3872-sec-0003" sec-type="section"> <title>CONCLUSION</title> <p id="ps3872-para-0003">Mutations in the sodium channel in pyrethroid‐resistant aphids also protect against a fusion protein containing a sodium‐channel‐specific toxin, in spite of differences in ligand–channel interactions, but do not confer resistance to a fusion protein targeting calcium channels. The use of fusion proteins with differing targets could play a role in managing pesticide resistance. © 2014 Society of Chemical Industry</p> </sec> </abstract>