CENTENNIAL HONORS COLLEGE
Western Illinois University
Undergraduate Research Day 2015
Poster Presentation
Levels of Cannibalism in Helicoverpa Zea Larvae Raised on Different Plants
Gina Meier, Simeon Ogundiran, Raysa Brito DeMagalhaes, and Yvette Ortiz
Faculty Mentor: Richard Musser
Biology
The Helicoverpa zea caterpillar is an agricultural pest that feeds on a variety of plants. This caterpillar
also regularly engages in cannibalism, consuming other caterpillars in close proximity. It seems the
presence of plant defense toxins such as nicotine found in tobacco plants can increase the rate of
cannibalism by the caterpillar (Gog et al., 2014). We are investigating whether other host plants can
increase the frequency of cannibalism in H. zea. We performed a preference test that suggests that the
caterpillar would prefer to feed on tomato leaves more than soybean leaves. We thus hypothesize that the
frequency of cannibalism will be higher for caterpillars when soybean leaves are present in comparison to
tomato leaves. Additionally, we plan to examine whether rates of cannibalism increase when plant
defenses have been stimulated by plant defense hormones such as jasmonate. We will measure the gene
expression of caterpillars to see if any compensatory response genes are stimulated. We ask the question
of whether caterpillar cannibalism in relation to plant defenses is a compensatory response by caterpillars
to anti-nutritive defenses or if it is a plant defense mechanism triggered by the plant.