You are here

Harvard Forest >

Harvard Forest Symposium Abstract 2013

  • Title: Insect and fungal communities of carnivorous pitcher plants
  • Primary Author: Leonora Bittleston (Massachusetts Institute of Technology)
  • Additional Authors: Anne Pringle (University of Wisconsin - Madison)
  • Abstract:

    Carnivorous pitcher plants hold water in their cup-shaped leaves, and passively trap insects. The plants exhibit exquisite convergent evolution: pitcher plant morphology and function has evolved separately in distant lineages in different parts of the world. Fungi, bacteria, and aquatic insects live within these microcosms and putatively assist in nutrient acquisition from prey.



    At Harvard Forest, we have looked at the effects of insect exclusion on the microbes within the Northern pitcher plant, Sarracenia purpurea. The insect exclusion treatment successfully excluded the keystone mosquito species Wyeomyia smithii, and greatly decreased numbers of other insects. The abundance of yeasts in cultures of pitcher fluid was positively correlated with insect counts, indicating that insects introduce, attract, or promote the growth of yeasts. Additionally, we found that one commonly associated yeast, Candida glaebosa, is present internally in surface-sterilized adult W. smithii, suggesting that the pitcher plant mosquito acts as a vector and may have a more complex association with this yeast.



    Preliminary data show high similarity among the insect and arachnid families associated with Southeast Asian and American pitcher plants of the genera Nepenthes and Sarracenia. Future research at Harvard Forest will examine how Sarracenia purpurea insects and microbes colonize similar but foreign Nepenthes hosts, versus artificial control pitchers.

  • Research Category: Biodiversity Studies
    Physiological Ecology, Population Dynamics, and Species Interactions