Submitted to: Entomological Society of America Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 12/18/2005
Publication Date: 11/6/2005
Citation: Natwick, E.T., Behle, R.W., Cardoza, R.E., Lopez, M.I. 2005. Evaluation of insecticide bait formulations and various insecticides for control of darkling beetles, Blapstinus spp. (Coleoptera: Tenebrionidae) [abstract]. Entomological Society of America. Paper No. 21653.
Technical Abstract: Nine insecticide baits and a control were evaluated for efficacy against darkling beetles Blapstinus spp., in cantaloupe at Holtville, CA. Randomized complete block design field plots, with four replicates, measured 15.25 meters x 8.13 meters. Insecticide baits were applied at two-week intervals in May and June. Baits included two Gowan Company products, 5% carbaryl bran bait and 0.5% permethrin grape pumis bait; two Wilber Ellis Company products, 5% carbaryl bran pellets and 5% carbaryl bran crumbles; two DuPont products, 0.22% indoxacarb corn grit granules and 0.045% indoxacarb corn grit granules; and four baits formulated by USDA-ARS-NCAUR consisting of pre-gelatinized corn flour granules with 20% montmorillonite clay and cantaloupe rind juice baits with 5% carbaryl, 1% imidacloprid, 5% spinosad, or no insecticide, respectively. Beetle populations in field plots were evaluated via two methods. First, numbers of beetles beneath 20 melons per plot were recorded. Second, beetles beneath 10 potato slices, 6.35 millimeters thick, per plot were recorded after 12 hours. Laboratory experiments consisted of choice tests evaluating attractiveness and no-choice tests evaluating toxicity. Beetle counts in the field experiment were consistently lower in 0.5% permethrin grape pumice baited plots. In the no-choice laboratory experiment, the 0.5% permethrin grape pumice bait treatment had the most rapid knock-down and highest mortality, followed by 5% carbaryl bran bait. In the choice tests, 0.5% permethrin grape pumice bait was among the most attractive. A comparison of the four formulations of pre-gelatinized corn flour granules showed that bait with no insecticide was more attractive than insecticide formulations.