Assessment of the effects of novel insecticides on green peach aphid (Myzus persicae) feeding and transmission of Turnip mosaic virus (TuMV)

Abstract

BACKGROUND Laboratory bioassays using treated leaf disks of peach were conducted to determine the efficacy of nine insecticides against the green peach aphid (GPA), Myzus persicae (Sulzer). The effects of these insecticides on aphid feeding behaviors and rates of transmission of Turnip mosaic virus (TuMV) to potted rutabaga plants were also determined. RESULTS Median lethal concentration (LC50) values after 48 h feeding varied considerably, ranging from lows of 1.5 and 4.6 μg a.i./L for sulfoxaflor and λ‐cyhalothrin, respectively, to 97.2 and 167.9 μg a.i./L for flonicamid and spirotetramat. LC50 values were lowest and roughly equivalent for λ‐cyhalothrin (1.2) acetamiprid (2.1), sulfoxaflor (0.23) and flupyradifurone (2.3) after 72 h feeding. Electrical penetration graph (EPG) recordings showed modest effects on feeding behaviors for certain insecticides, with sulfoxaflor, spirotetramat, and acetamiprid non‐significant reduction in feeding duration and number of pathway and potential drop phases occurring during the first 5 min compared with the control. However, greenhouse experiments carried out to investigate the effect of these insecticides on rates of transmission of TuMV, which is transmitted non‐persistently by GPA, resulted in only modest non‐significant reductions in infection rates for acetamiprid, pymetrozine, λ‐cyhalothrin, and flonicamid of 27%, 23%, 20%, and 17%, respectively. CONCLUSION All test materials were efficacious to GPA at differing levels, and some such as sulfoxaflor and acetamiprid non‐significantly reduced the duration and number of pathways and potential drop phases of feeding within the first 5 min. None, however, resulted in significant reductions in rates of transmission of TuMV. © 2020 Her Majesty the Queen in Right of Canada. Pest Management Science © 2020 Society of Chemical Industry

Sublethal concentrations of pymetrozine reduce Sogatella furcifera transmission of Southern rice black‐streaked dwarf virus

“…15 As expected, we found that the honeydew excretion (feeding amount) of WBPH fed with rice plants treated with LC 10 and LC 50 of pymetrozine significantly decreased with increasing insecticide concentration. Similar results have been reported in Aphis fabae Scopoli, 15 Myzus persicae (Sulzer), 16,18,20 Nilaparvata lugens. 35 It is suggested that pymetrozine selectively interferes with the regulation of feeding behavior which finally results in starvation.…”

“…19 Nevertheless, in a glasshouse test, pymetrozine afforded only a modest non-significant reduction (23%) in infection of TuMV. 20 In another test, pymetrozine was not constant in reducing the spread of PVY. 21 Plant virus transmission is closely associated with specific probing behaviors of the insect vectors.…”

“…Due to its interfering with feeding behavior, pymetrozine has been employed to combat plant virus spread, significantly reducing the transmission of Cauliflower mosaic virus (CMV), 16 Potato virus Y (PVY) and Potato leafroll luteovirus (PLLV), 17,18 and the infection of sweet potatoes by Sweet potato leaf curl virus (SPLCV) 19 . Nevertheless, non‐significant effects of pymetrozine on virus spread have also been reported, such as moderate reduction in infection rate of rutabaga plants by Turnip mosaic virus (TuMV) 20 and sporadic reduction of PVY spread in a limited period of time after insecticide application 21 . Currently, the effects of pymetrozine on WBPH transmission of SRBSDV are not known, though WBPH feeding behaviors have been recorded by electrical penetration graph (EPG) in relation with pymetrozine treatment 22 .…”

Turnip mosaic virus, a virus for all seasons

“…Since Shattuck (1992), many new insecticides have been released, however, some of those more effective in killing aphids, for example the neonicitinoids have been banned on most crops in Europe (Regulation (EU) No 485/2013, The European Commission, 2013). Despite recent experiments on the efficacy of nine “novel” insecticides against the green peach aphid, M. persicae , none resulted in significant reductions in rates of transmission of TuMV (Samara, Lowery, Stobbs, Vickersa, & Bittnera, 2021).…”

Producing sugar beets without neonicotinoids: An evaluation of alternatives for the management of viruses-transmitting aphids

“…Brassica napus subsp. rapifera(Samara et al 2021). Spirotetramat, another systemic insecticide authorized on several crops in the EU (including sugar beets), inhibits lipid biosynthesis in sap-sucking insects, including mealybugs, psyllids, aphids, gall midges.…”