Chemical and tactile cues influencing oviposition of a generalist moth, Spodoptera frugiperda (Lepidoptera : Noctuidae)

The current study was undertaken to investigate the role of the chemical and tactile cues in host-plant selection by Spodoptera frugiperda (Smith). Adult female S. frugiperda seemed Dot to depend on plant volatiles for orientation to host plants. In general, females oviposited more on control areas than on areas treated with leaf extracts of corn, cotton, and tomato. This outcome was independent of extraction duration (1 or 60 min) or solvent (hexane or methanol). The hexane extract of corn inhibited oviposition at doses of 1 and 0.2 g/ml but not at 0.005 and 0.001 g/ml. The methanolic leaf extract decreased oviposition at dosages of 1, 0.2, and 0.005 g/ml but not at a dosage of 0.001 g/ml. S. frugiperda females deposited more eggs on grooved or pitted surfaces than on smooth surfaces. Tactile cues seemed to be highly important during oviposition and could neutralize the deterrent effect of the corn leaf extracts; females oviposited on grooved surfaces independently of the presence or absence of leaf extracts.