The Function of Insect Trapping by Penstemon Digitalis and Cirsium Discolor

The capture of insect by sticky secretions occurs in many plant species in many plant families throughout the world. In a few cases such insect-trapping plants have been shown to be carnivorous, e.g., Drosera spp. and Pinguicula spp., and in some cases they have been shown to provide defense against herbivores. In most plants, however, the function of such insect-trapping is not known. In two herbaceous plants native to central Illinois, Penstemon digitalis Nutt. (Scrophulariaceae) and Cirsium discolor (Muhl) Spreng (Compositae), sticky substances that capture insects are produced in the inflorescences. I tested four hypotheses as to the function of insect-trapping in these two plant species: (1) Direct defense against herbivores; (2) Indirect defense against herbivores by attraction of predatory arthropods; (3) Direct nutrition of the plant by digestion and absorption of insects in the trap areas; and (4) Indirect nutrition by absorption of products of decay leached into the ground from the captured insects.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Ecology, Evolution, and Conservation Biology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Thomas, Patricia Ann

Contributors dc:contributor

• Willson, Mary F.,

• Biology, Botany
• Biology, Ecology

Language dc:language

eng

Identifier

(UMI)AAI8908867

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/77627