Insecticidal Activity of a Petroleum-Derived Spray Oil and an Organosilicone Surfactant on Listronotus maculicollis (Kirby) Adults in Laboratory and Greenhouse Bioassays

Abstract

The annual bluegrass weevil (ABW), Listronotus maculicollis (Kirby), is a severe pest of golf course turf in eastern North America. The development of pyrethroid- and multiple-resistant populations has created a dire need for novel tactics to control adults. We examined the insecticidal properties of a petroleum-derived spray oil (PDSO; Civitas Turf Defense™.) and an organosilicone, nonionic soil surfactant (Silwet L-77®) in laboratory and greenhouse bioassays. Civitas and Silwet killed > 75% of ABW adults in multiple assays. The level of control was positively affected by increased rate, spray application volume, and soil moisture levels. Dissections of weevils treated with Civitas revealed material entering the insect’s hemocoel after 15–30 min, though most mortality occurred between the 3 and 24 h observation periods. Reducing rates while increasing carrier volume or soil moisture levels through irrigation applied prior to or after application also provided excellent control of adults in the same observation periods. Silwet provided comparable, yet less consistent levels of control in the laboratory studies but was excluded from further tests after treated plants demonstrated phytotoxicity in greenhouse studies. Neither Silwet nor Civitas efficacy was affected by pyrethroid resistance levels in the ABW populations tested.

Bee Pollinator Mortality Due to Pesticide-Laden Particulate Matter from Beef Cattle Feedyards

“…Bees sited downwind of feedyards became coated with PM, which may have exacerbated toxicity by clogging spiracles and potentially inducing anoxia (see Figure S2). 45 Recent laboratory-based experiments have demonstrated that agrochemical-free PM generated from organic cattle manure is not toxic to pollinators 46 which indicates that agrochemicals bound to fugitive feedyard PM are most likely responsible for the elevated mortality observed among bees sited downwind of feedyards in the present study. Additionally, pesticides that were not included in our analyses, but nevertheless previously documented to occur in fugitive feedyard PM (e.g., piperonyl butoxide, boscalid, pyraclostrobin, etc.…”

Effectiveness of Agave genotype extracts applied alone or mixed with mineral oil against the cactus scale mealybug Diaspis echinocacti (Hemiptera: Diaspididae)

“…On the other hand, the high mortality of D. echinocacti with mineral oil, alone, is due to the action Mode of this material, covering the waxy carapace of scale insects with a thin film and killing them by asphyxiation (Martín-López et al 2006). Furthermore, mineral oils are non-polar and therefore more likely to penetrate the hydrophobic integument of the scale mealybug (McGraw et al 2022) as shown for eggs, nymphs, and adults of the mealybugs Lepidosaphes beckii (Newman) and Parlatoria ziziphus (Lucas) (Hemiptera: Diaspididae) on citrus plants treated with mineral oil in Sheben El-Kanater, Caliubia province, Egypt (Helmy et al 2012).…”