PARENT SESSION
Oral Session #45: Herbivory: Effects on Plants. Presiding: T. Craig.
Wednesday, August 8, 2001. 8:00 AM to 12:00 PM. Hall of Ideas H.
Maternally induced plant resistance: genetic variation, signals, and consequences.
Agrawal, Anurag1, 1
ABSTRACT- Herbivory has many consequences for plants, including effects on the characteristics of seeds and seedlings that maternal plants produce. I have been studying the plant responses to herbivory in wild radish plants. Within a generation, plants induce glucosinolates and are protected against subsequent attack. In addition, the progeny that are produced by damaged plants have variable size, germination, and growth, and the direction of these effects is variable among plant families. The seedlings that are produced by damaged plants are more resistant to caterpillars than the seedlings produced by undamaged plants. This effect on progeny can be stimulated by caterpillar herbivory or treatment of maternal plants with jasmonic acid, a natural elicitor of induced plant responses. Progeny of plants clipped with scissors were more susceptible to caterpillars than progeny of control plants. These results suggest that defense induction across plant generations is stimulated by induced response pathways, and not by leaf tissue loss. Maternal effects associated with herbivory affect growth and defense of progeny plants and may be subject to natural selection.
KEY WORDS: induced defense, herbivory, maternal effect