Techniques for Studying Pollen Adhering to Nectar-Feeding Corn Earworm (Lepidoptera: Noctuidae) Moths Using Scanning Electron Microscopy

Corn earworm, Helicoverpa zea (Boddie), male moths (399) were collected from sexpheromone traps during spring and late summer for determination and identification of attached pollen. Comparisons made between dissecting light and scanning electron microscopy (SEM) show that direct mounting and viewing by SEM is a much more reliable technique for locating and separating pollen from other debris and for identifying pollen types. Red fingernail polish provides good conductive surfaces and better bonding for mounting specimens to SEM stubs than does silver paint and several other mounting media. Viewing all moth specimens by SEM is more costly, but added cost is partially offset by time saved in eliminating the preliminary examination by dissecting microscopes (≈ 15 min per specimen). About 3.5 h are required for preparation, analysis, and reporting result from individual moth specimens when using only SEM.