Assessing the value and pest management window provided by neonicotinoid seed treatments for management of soybean aphid (Aphis glycines Matsumura) in the Upper Midwestern United States

Abstract

These data demonstrate that an IPM approach, combining scouting and foliar-applied insecticide where necessary, remains the best option for treatment of soybean aphids, both in terms of protecting the yield potential of the crop and of break-even probability for producers. Furthermore, we found that thiamethoxam concentrations in foliage are unlikely to effectively manage soybean aphids for most of the pests' activity period across the region. © 2017 Society of Chemical Industry.

Interactions of effects of host plant resistance and seed treatments on soybean aphid (Aphis glycines Matsumura) and soybean cyst nematode (Heterodera glycines Ichinohe)

“…Previous studies found that neonicotinoid seed treatments like thiamethoxam do not consistently prevent A. glycines populations from reaching economically damaging levels . This inconsistent reduction in A. glycines populations with neonicotinoid seed treatments often is a result of the timing of A. glycines colonization, which typically occurs when the concentration of the neonicotinoid compounds in the soybean tissues has diminished . Furthermore, thiamethoxam did not provide additional suppression of A. glycines populations on Rag1 soybeans in our plots, which may have been a result, in part, of the overall low A. glycines populations on those Rag1 cultivars.…”

Neonicotinoid Seed Treatments: Limitations and Compatibility with Integrated Pest Management

“…Although some studies have identified benefits (e.g., North et al, 2016; Hurley and Mitchell, 2017), evidence for their value has proven elusive in many, if not most, cases. The hallmark of peer‐reviewed studies on NST effects in corn and soybean production is variability in yield and economic effects among fields, years, and regions (reviewed in Douglas and Tooker, 2015; see also North et al, 2016; Hurley and Mitchell, 2017; Krupke et al, 2017a, 2017b). The primary explanation for this inconsistency is that NST mainly target occasional, soil‐dwelling pests (e.g., wireworms, white grubs, seedcorn maggot), populations of which are typically low and sporadic over space and time.…”

“…Surveys indicate that farmers infrequently perceive these pests as important problems (Fernandez‐Cornejo and Jans, 1999; Hurley and Mitchell, 2014). A secondary explanation is that the potential for neonicotinoids to benefit the crop is quite low because the active ingredient is only detectable in plant tissues for 2 to 3 wk after planting (Krupke et al, 2017a; Alford and Krupke, 2017). In other words, benefits can only be realized when economically damaging populations of relatively uncommon pests intersect with short‐lived insecticides in plant tissues.…”

“…Some active ingredient is lost during planting due to abrasion of seeds and release of contaminated dust (Krupke et al, 2012, 2017b), but a far larger amount (the majority of what is applied to the seed) is lost due to the high water solubility of these compounds (USEPA, 2003; US National Library of Medicine, 2017). The amount of neonicotinoid applied to seeds that actually gets absorbed by plants is typically about 1 to 10%; the rest remains in soil where it is vulnerable to leaching (Alford and Krupke, 2017; Krupke et al, 2017a).…”

Efficacy of afidopyropen against soybean aphid (Hemiptera: Aphididae) and toxicity to natural enemies

“…7 Foliar insecticides used for A. glycines management are generally from only three insecticide sub-groups: pyrethroids (Group 3A), organophosphates (Group 1B) and neonicotinoids (Group 4C), 10 with pyrethroids and organophosphates most commonly used. 8 This approach to management of A. glycines has proven effective, [11][12][13] but reliance on relatively few broad-spectrum insecticides increases risks for ecological backlash through impacts to natural enemies and development of resistance in the pest. 14 Aphis glycines is attacked by a diverse suite of natural enemies, including predators, parasitoids and pathogens.…”