Methylcyclopentanoid Monoterpenes Mediate Interactions Among Insect Herbivores
MICHAEL J. RAUPP 1,
FRANK RIVERA MILAN 1,
PEDRO BARBOSA 1, and
BARBARA A. LEONHARDT 2
1 Department of Entomology, University of Maryland, College Park, MD 20742.
2 Insect Chemical Ecology Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD 20705.
Beetles secrete an array of chemicals generally believed to mitigate attack by predators. Methylcyclopentanoid monoterpenes secreted by larvae of the willow leaf beetle, Plagiodera versicolora, deter feeding by conspecific adults. Furthermore, the secretion elicits a strong repugnancy response in larvae of another willow herbivore, Nymphalis antiopa. Leaves bearing beetle larvae are less likely than leaves not bearing beetles to be frequented and consumed by Nymphalis larvae. Predator defense may not be the sole function of glandular secretions produced by herbivorous insects; secretions may also mediate interactions among herbivores that use a common resource.
Submitted on November 25, 1985
Accepted on February 14, 1986
