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A novel trap designed to catch sap beetles and many other insects is described. This trap is durable, being manufactured from PVC pipe and brass screen. The modular trap orients in the wind such that air flows over screened-off bait compartments and through a screen funnel entrance. Insects approach and enter from down-wind and become trapped after passing through a wire mesh funnel. They subsequently move through a connecting tube, through an additional funnel, and into a removable collector. Catches of sap beetles were superior to a commercially available Japanese beetle trap. Several thousand sap beetles (primarily Carpophilus lugubris Murray) could be captured with appropriate baits over a 1-wk period. Fungi from the trapped sap beetles included Aspergillus flavus Link:Fr. and numerous common genera with species recognized as plant pathogens, entomopathogens, saprophytes, or biocontrol agents. Other families of insects that contain pests and were captured include Cantharidae, Chrysomelidae, Elateridae, Culicidae, Drosophilidae, Muscidae, Vespidae, and Noctuidae.

Toxicity and rates of ester hydrolysis of the pyrethroids fenpropathrin, fenvalerate, fluvalinate, cis- and trans-permethrin, and tralomethrin to third and last instars of the soybean looper, Pseudoplusia includens (Walker), and the tobacco bud worm, Heliothis virescens (F.), were determined. Tralomethrin was the most toxic to both stages for both species, while trans-permethrin and fenpropathrin were generally the least toxic. All pyrethroids were more toxic to third instars than to last instars for both species. In general, H. virescens larvae were less susceptible than P.includens larvae. Trans-permethrin was hydrolyzed at the greatest rate in both stadia of both insect species. Fenpropathrin was generally hydrolyzed at the lowest rate. Rates of hydrolysis were similar or less in last instars of both species compared with third instars.

The 1-naphthyl acetate esterase activity from the cell-free preparation of cultures of the yeast-like symbiont, Symbiotaphrina kochii Jurzitza ex. W. Gams and v. Arx, of the cigarette beetle, Lasioderma serricome (F.), was investigated with isoelectric focusing, gel filtration chromatography, selective inhibition, and temperature and solvent stability studies. Gel filtration indicated that activity was predominantly due to one enzyme (or closely related enzyme forms) with a molecular weight of approximately 38,000. The isoelectric point of most of the activity ranged from pH 4.6 to 4.8. The presence of three bands in this region suggested that isoenzymes were present. The apparent Km for the symbiont esterase was 114 μM and the Vmax was 8.9 nmole/rnin/mg protein. The symbiont esterase was relatively resistant to acetone, sensitive to temperature treatments, and partially inhibited by relatively high concentrations of organophosphates and thiol reagents, but not by chelators.

Midgut-mediated ester cleavage of p-nitrophenyl acetate increased in Trichoplusia ni (Hübner) larvae that were fed on diets containing extracts from resistant and susceptible soybean, Glycine max (L.) Merr., varieties. Activity ranged as follows: control < susceptible < resistant variety. The opposite trend was noted for ester cleavage by midguts of Pseudoplusia includens (Walker) larvae fed on the same diets, such that activity ranged as follows: control > susceptible > resistant variety. The use of the inhibitors piperonyl butoxide and S,S,S-tri-n-butyl phosphorotrithioate indicated that ester cleavage was primarily mediated by hydrolytic esterases.