Behavioral responses, rate of mortality, and oviposition of western cherry fruit fly exposed to malathion, zeta-cypermethrin, and spinetoram

Abstract

Western cherry fruit fly, Rhagoletis indifferens Curran (Diptera: Tephritidae), is a pest of sweet and tart cherry, Prunus avium L. (L.) and P. cerasus L., respectively, in western North America. This fly is commonly controlled with spinosad bait sprays. Spotted wing drosophila, Drosophila suzukii Matsumura, is potentially a new pest of cherries in this region that could be a threat to orchards at the same time as R. indifferens. Drosophila suzukii apparently is not controlled using spinosad bait sprays, but may potentially be controlled using malathion, zeta-cypermethrin, and spinetoram. However, how well these last three materials protect fruit against reproductively mature R. indifferens is not known. In laboratory observations, R. indifferens spent the least amount of time on cherries treated with zeta-cypermethrin, possibly because of its toxicity and irritant effects. In laboratory experiments, zeta-cypermethrin killed flies more quickly than malathion and spinetoram, causing up to 100% mortality 2 h after exposure. Zeta-cypermethrin prevented all oviposition when flies walked on dried residues for 20-25 min or were directly sprayed, and then exposed to cherries with dried residues, simulating exposure of mature female flies in a treated orchard. Malathion and spinetoram reduced oviposition compared with controls, but did not prevent it, when flies contacted residues or were directly sprayed at a high volume. Results suggest zeta-cypermethrin is the most effective of the three materials at protecting cherries against mature R. indifferens and could be used in an integrated control program for it and D. suzukii.

Comparative Efficacy of Insecticides on Bactrocera tryoni and Zeugodacus cucumis (Diptera: Tephritidae) in Laboratory and Semifield Trials in Fruiting Vegetables

“…Reynolds et al (2014) found spinetoram to be moderately effective on mortality of B. tryoni in laboratory tests. Likewise, Yee and Alston (2012) found that this chemical resulted in 81% mortality of R. indifferens females exposed to residues on cherries at Means with a letter in common are not significantly different (LSD test; P > 0.05).…”

“…Mean number of pupae developing from zucchini exposed to Z. cucumis in season two trials; back-transformed means (BTM) and predicted means on the log scale 6 1 standard error (PM) 24 h, and reduced oviposition compared to controls. Both Reynolds et al (2014) and Yee and Alston (2012) applied treatments and aged residues under laboratory conditions. Yee et al (2007) found that aging of spinetoram residues under field conditions resulted in reduced mortality of adult R. pomonella; however, residues remained effective up to 14 d in terms of preventing oviposition.…”

“…Reynolds et al (2014) found that efficacy of alpha-cypermethrin against B. tryoni was comparable to fenthion in semifield tests. Various isomers of cypermethrin have demonstrated efficacy against tephritids, for example, cypermethrin reduced infestation and increased yield in a trial to manage Bactrocera spp in cucumber (Sharma et al 2016); residues of zeta-cypermethrin on cherries effectively reduced oviposition by R. indifferens (Yee and Alston 2012); fresh cypermethrin residues on cucumber prevented oviposition by Dacus ciliatus Loew, the lesser pumpkin fly (Maklakov et al 2001). Efficacy of the second synthetic pyrethroid assessed, bifenthrin (Talstar 250 EC Insecticide/Miticide) was also comparable with dimethoate in a field cage trial against B. tryoni.…”

“…A number of studies have examined the toxicity of pesticides to tephritid fruit flies in the laboratory using a range of methods such as direct application to adult flies (Wang et al 2013), exposure to residues on artificial substrates (Mosleh et al 2011), exposure to residues on fruit applied and aged in the laboratory (Maklakov et al 2001, Yee 2008, Yee and Alston 2012 or the field (Yee et al 2007, Rahman andBroughton 2016), or application of insecticide sprays to infested fruit (Wise et al 2009). Small plot field trials have been employed to assess efficacy of insecticides for management of cucurbit-specific fruit flies such as Z. cucurbitae in cucurbits (Oke 2008, Khursheed and Raj 2012, Oke and Sinon 2013, and field trials conducted in tree crops for management of Rhagoletis spp.…”

Mechanism and effectiveness of safflower oil against female Queensland fruit fly Bactrocera tryoni

“…In general, a cover spray will result in faster population reduction than toxic bait application as shown in the laboratory (Raga & Sato, , ). In addition to direct (topical) exposure, cover spray may kill flies through tarsal contact and/or ingestion of residue (Yee & Alston, ). Another advantage of some chemical cover sprays is that they can kill eggs and larvae in the infested fruits, though this effect depends not only on toxic but also on penetrative properties of the insecticides (Wise et al., ).…”