Greenhouse studies were conducted from 1996 to 1998 to determine the efficacy of spinosad, and acephate, against western flower thrips (Frankliniella occidentalis Pergande) on transvaal daisy (Gerbera jamesonii H. Bolus ex. Hook f). In addition, the number of natural enemies inside and outside the greenhouse was determined. Studies were arranged in a randomized complete-block design with four blocks and four treatments per block. Three rates of spinosad, 50, 100, and 200 mg·L-1 (ppm), and one rate of acephate, 600 mg·L-1 were used in all three studies. Plants were artificially inoculated at bloom with 10 adult western flower thrips. The number of live and dead thrips was counted from each plant. In all three studies, both spinosad and acephate controlled thrips. However, there was more variation in the average number of live thrips for acephate than spinosad across years. In all treatments fewer live thrips and more natural enemies were found on plants outside the greenhouse than inside the greenhouse. This suggests that placing plants outdoors allows the natural enemies of thrips to colonize plants and provide supplemental control.
Raymond A. Cloyd and Clifford S. Sadof
Rebecca L. Loughner, Daniel F. Warnock, and Raymond A. Cloyd
Western flower thrips (Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)] collected from greenhouse, laboratory, and native populations were evaluated for resistance to the insecticide spinosad. Individual cut stems of transvaal daisy (Gerbera jamesonii H. Bolus ex Hook. f.) were inoculated with 25 adults from 1 of 9 thrips populations and maintained in isolation chambers. Treatments of no spray, water spray, spinosad at one-half label rate (0.41 mL·L-1) and spinosad at the recommended label rate (0.81 mL·L-1) were applied to the flowers. Three days after treatment, the number of live and dead thrips was recorded. Significantly more thrips were recovered from the control treatments than the spinosad treatments. Thrips survival varied by treatment and insect population. Based on an odds ratio analysis, the likelihood of recovering live thrips was greater in the IL-GH1 (Illinois greenhouse) population than in the NV-N1 (Nevada native) reference population for both spinosad treatments, suggesting resistance to spinosad in the IL-GH1 population. The IL-GH1 population was collected from a greenhouse regularly sprayed with spinosad whereas the NV-N1 population was collected in Incline Village, Nev., on wildflowers with no history of exposure to spinosad. This is the first documented indication of spinosad resistance in a thrips population. In comparison to the NV-N1 reference population, none of the populations collected from laboratory or native nonagricultural environments exhibited evidence of resistance to spinosad. Resistance to an insecticide with a novel mode of action, such as spinosad, indicates the necessity of rotating insecticides and implementing alternative methods of managing western flower thrips. Chemical names used: spinosad including spinosyn A and spinosyn D (Conserve SC).
Melissa Bonham, Gerald M. Ghidiu, Erin Hitchner, and Elwood L. Rossell
compare the effectiveness of a seed treatment of fipronil, an in-furrow application of thiamethoxam, and multiple foliar applications of spinosad or diazinon directed at the base of the plant for control of the carrot weevil in processing carrot. Materials
Suzette P. Galinato, R. Karina Gallardo, David M. Granatstein, and Mike Willett
applications of spinosad (Entrust; Dow AgroSciences, Indianapolis, IN) to control for potential apple maggot infestation. The detailed partial budgets are presented in Supplemental Tables 1 – 3 . Table 5 summarizes the partial budgets. Table 5. Annual profit
James D. Spiers, Fred T. Davies Jr., Chuanjiu He, Carlos E. Bográn, Kevin M. Heinz, Terri W. Starman, and Amanda Chau
This study evaluated the influence of insecticides on gas exchange, chlorophyll content, vegetative and floral development, and plant quality of gerbera (Gerbera jamesonii Bolus `Festival Salmon'). Insecticides from five chemical classes were applied weekly at 1× or 4× their respective recommended concentration. The insecticides used were abamectin (Avid), acephate (Orthene), bifenthrin (Talstar), clarified hydrophobic extract of neem oil (Triact), and spinosad (Conserve). Photosynthesis and stomatal conductance were reduced in plants treated with neem oil. Plants treated with neem oil flowered later—and at 4× the recommended label concentration had reduced growth, based on lower vegetative dry mass (DM) and total aboveground DM, reduced leaf area, thicker leaves (lower specific leaf area), higher chlorophyll content (basal leaves), and reduced flower production. Plants treated with acephate at 4× the recommended label concentration were of the lowest quality due to extensive phytotoxicity (leaf chlorosis). Plants treated with 1× or 4× abamectin or spinosad were of the highest quality due to no phytotoxicity and no thrips damage (thrips naturally migrated into the greenhouse). The control plants and plants treated with 1× bifenthrin had reduced quality because of thrips feeding damage; however gas exchange was not negatively affected.
Kathleen Delate, Andrea McKern, Robert Turnbull, James T.S. Walker, Richard Volz, Allan White, Vincent Bus, Dave Rogers, Lyn Cole, Natalie How, Sarah Guernsey, and Jason Johnston
-baited sticky traps to monitor leafroller populations in the orchard, Bacillus thuringiensis early in the season, Entrust (an organic insecticide released in 2003, developed from a soil-dwelling fungus, spinosad) later in the season, and a rigorous selection
Devin L. Radosevich, Raymond A. Cloyd, and Nathan J. Herrick
thrips in greenhouses and a water control. Experiments were set up as a completely randomized design. One transvaal daisy cut flower was considered an experimental unit. The three insecticides and application rates were as follows: spinosad (Conserve SC
Raymond A. Cloyd
spinosad (Conserve®; Dow AgroSciences, Indianapolis, IN); abamectin and azadirachtin [Azatin® (OHP, Mainland, PA) and Ornazin® (SePro, Carmel, IN)]; and acephate (Orthene®; Valent U.S.A., Walnut Creek, CA) and fenpropathrin (Tame®; Valent U.S.A.). The two
Raymond A. Cloyd and Amy L. Raudenbush
; Cloyd et al., 2009 ; Willmott et al., 2013 ). A number of the pesticides used in this study are classified as selective. These include spinosad (Conserve ® ; Dow AgroSciences, Indianapolis, IN), pyridalyl (Overture ® ; Valent U.S.A., Walnut Creek, CA
Raymond A. Cloyd and Joshua D. Gillespie
tau-fluvalinate at 8.0 fl oz/100 gal (Mavrik Aquaflow ® ; Wellmark International, Schaumburg, IL), pyridalyl at 8.0 oz/100 gal (Overture ® ; Valent U.S.A. Corp., Walnut Creek, CA), and spinosad at 6.0 fl oz/100 gal (Conserve ® ; Dow AgroSciences