Fall Armyworm Symposium: Effect of Corn Foliar Cuticular Lipids on the Movement of Fall Armyworm (Lepidoptera: Noctuidae) Neonate Larvae

Authors

  • Guang Yang
  • Karl E. Espelie
  • B. R. Wiseman
  • David J. Isenhour

Abstract

Genotypes of corn known to vary in their resistance to fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), were utilized in a study designed to examine the plant resistance role of surface ultrastructure and cuticular lipids. Scanning electron microscopy showed dramatic differences between the ultrastructural appearance of lower (4th) and upper (8th) leaves of the resistant MpSWCB-4 and the susceptible Cacahuacintle X's. In a choice test, FAW larvae preferred the upper leaves from which the cuticular lipids had been removed over untreated leaves of these two genotypes. Larval behavior was monitored by video camera on the adaxial and abaxial surfaces of upper and lower leaves of MpSWCB-4 and Cacahuacintle X's and on foliage samples with and without cuticular lipids. FAW showed more nonacceptance behavior on the untreated foliage than on the chloroform-extracted foliage. FAW larvae traveled greater distances and crawled faster when they were on upper leaves rather than lower leaves and when they were on the abaxial leaf surface rather than the adaxial surface. However, no difference in behavior was found when larval movement was monitored on the cuticular lipid extracts from the foliage of two resistant and two susceptible corn genotypes.

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Published

1993-06-01

Issue

Section

Literature Review Articles