Defense against herbivory in Passiflora incarnata
Plants have evolved a myriad of chemical, mechanical and biological defense mechanisms that deter insect predators (herbivores). Because these defenses can be costly, production of the substance or morphology is sometimes induced by the presence of an herbivore, but produced in low levels, or not at all, when herbivores are absent. Passionflower (Passiflora incarnata) employs multiple defense mechanisms. In addition to the production of a chemical (hydrogen cyanide) that is toxic to many insects, plant leaves also have glands that secrete nectar that attract ants who prey on potential herbivores. The results of my research in the summer of 2011 suggest that the removal of leaf area on individual plants results in both an increase in the volume of nectar secreted and the thickness of leaves. I am currently asking whether the production of the chemical defense was also increased and whether the induction of increased leaf nectar is accompanied by the induction of other defense mechanisms and/or if genetic differences in nectar production (identified previously) are correlated with greater (or lesser) chemical or mechanical protection.
Student Collaborators
Anjum Somji
Aimee Beauchamp
Tabitha Marchbanks
Caleb Matthews
Nick Konstantinidis