Feeding-Site Preference of Fall Armyworm, Corn Earworm, and Granulate Cutworm (Lepidoptera:Noctuidae) on Florunner Peanut1

Abstract

Abstract The feeding-site preferences of fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), corn earworm (CEW), Helicoverpa zea (Boddie), and granulate cutworm (GCW), Agrotis subterranea (F.) were studied on excised laterals and entire plants of Florunner peanut. Six larval size classes, based on head-capsule widths, were distinguished for FAW and GCW, and five for CEW. FAW and CEW larvae had very similar feeding behaviors. Both species fed primarily on the terminal three leaves of peanut laterals, but this preference for young foliage declined with larval age. All FAW and CEW size classes fed on blooms, with greatest incidence (21% of feeding observations) occurring in the second through fourth size classes. Axillary-bud feeding by FAW and CEW was greatest (23 and 17% of feeding observation, respectively) in the third size class. The last two larval size classes of FAW and CEW spent 20% of feeding time on R2 pegs. GCW fed primarily on blooms through the first four size classes. Foliage feeding by GCW remained ≤10% of feeding observations until the fifth size class. GCW did not feed on axillary buds in whole plant studies. Peg feeding by GCW peaked in the fourth and fifth size classes (36% of feeding observations). On whole plants, each FAW consumed 4.8 ± 1.2 tetrafoliate leaves, severed 6.3 ± 1.6 pegs, and damaged an additional 3.6 ± 1.7 pegs. Each CEW consumed 4.7 ± 0.8 leaves, severed 7.1 ± 1.6 pegs, and damaged 2.4 ± 1.4 pegs. Each GCW consumed 3.9 ± 0.5 leaves, severed 8.5 ± 2.0 pegs, and damaged 3.5 ± 1.3 pegs.